Skocz do pozycji: 1.

Tytuł:

Gyroplane rotors vibration tests

Autorzy:

Wojtas, M.
Trendak, M.

Powiązania:

https://bibliotekanauki.pl/articles/246317.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotor vibration
rotor blades
teetering rotor
hub connector
rotor imbalance

Opis:

The article presents vibration test of three different types of gyroplane main rotors. The test was carried out on a specially prepared test bench using a Red Led Tacho Sensor measuring system. Tests were conducted for the project „Research and development works on innovative construction of aircrafts of weight over 560 kilograms at the company Trendak Aviation”. The work outlines the basic properties of the gyroplane vibration and gives their sources. The research focused on the gyroplane main rotor vibration related inter alia to the rotor imbalance as well as rotor hub connector construction. Tested rotors consisted of three different types of gyroplane rotor blades and innovative universal hub connector with positive coning angle of 2.8º. The article summarized the basic properties of three types of gyroplane the rotor blade, marks advantages of use hub connector witch constructional dihedral angle. Discusses the principle of operation of measuring device, tests methodology starting from instrument calibration. The results of the measurements are shown in the graphs in polar coordinates. The vibration measurement is carried out in two axes, in x-axis, longitudinal, along the rotor radius and in y-axis, perpendicular to the x-axis, in the direction of the chord of the rotor blades.

Źródło:

Journal of KONES; 2017, 24, 4; 349-354
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 2.

Tytuł:

Determination of best rotor length in solid-rotor induction motor with axial slitting

Autorzy:

Jagiela, M.
Garbiec, T.

Powiązania:

https://bibliotekanauki.pl/articles/140492.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

prądy wirowe
silnik indukcyjny
solid-rotor
induction motor
rotor-end factor
eddy currents

Opis:

The efficiency of the solid-rotor induction machines depends on axial length of rotor (including the end-regions). Determination of the best axial length is problematic because of current density distribution in the end-regions and also because of absence of dedicated methods and models. This work proposes a method that circumvents this difficulty. It is based on the numerical determination of a dimensionless rotor-end factor using a combination of three- and two-dimensional finite element models restricted to the motor rotor. Such the end factor can be used in both analytical and numerical model of the machine in order to determine the typical performance characteristics. In this work, using this method, we determined an optimal length of the slitted solid rotor of a motor operating at 12 000 rpm, that maximizes the motor efficiency. The results of computations and measurements, carried out on the laboratory test-stand, are presented.

Źródło:

Archives of Electrical Engineering; 2012, 61, 2; 267-276
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

Comparison of higher harmonic contents in salient pole synchronous generator with different rotor construction

Autorzy:

Ludwinek, K.
Nadolski, R.
Staszak, J.

Powiązania:

https://bibliotekanauki.pl/articles/140521.pdf

Data publikacji:

2017

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

salient pole synchronous generator
higher harmonics
solid rotor
rotor with radial incisions
laminated rotor

Opis:

The paper presents a comparison of higher harmonics in induced phase voltages of a stator winding in the no-load state of a three-phase 5.5 kVA salient pole synchronous generator. The comparison is carried out for the synchronous generator with different salient pole rotor constructions: a non-skewed solid rotor, a non-skewed solid rotor with radial incisions, and a laminated electrotechnical steel rotor with skewed slots and damping bars. The calculations of higher harmonics are based on the magnetic field distributions in the air gap, which are carried out in a 2D model in a FEMM program and on the induced voltage waveforms in the stator windings registered during experimental investigations of the 5.5 kVA salient pole synchronous generator in the no-load state.

Źródło:

Archives of Electrical Engineering; 2017, 66, 1; 121-139
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

3D inviscid flutter of rotor blades and stator/rotor stage

Autorzy:

Rządkowski, R.
Gnesin, V.

Powiązania:

https://bibliotekanauki.pl/articles/1967639.pdf

Data publikacji:

2001

Wydawca:

Politechnika Gdańska

Tematy:

3D inviscid flutter
flutter
blades
stator/rotor stage
rotor blades
unsteady forces
3D finite element model

Opis:

The approach is based on solution of the coupled aerodynamic-structure problem for 3D flow through the turbine stage in which fluid and dynamic equations are integrated simultaneously in time. An ideal gas flow through the mutually moving stator and rotor blades with periodicity on the whole annulus is described by unsteady Euler conservation equations, which are integrated using the explicit monotonous finite-volume difference scheme of Godunov-Kolgan and moving hybrid H-H grid. The structure analysis uses the modal approach and 3D finite element model of a blade. A calculation was performed for the last stage of the steam turbine with rotor blades of 0.765 m.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 567-577
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 5.

Tytuł:

Anomaly of rotor dynamics in ultra-light helicopter – Robinson R22

Autorzy:

Sobieszek, Agnieszka

Powiązania:

https://bibliotekanauki.pl/articles/242430.pdf

Data publikacji:

2019

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotor hub
Robinson R22
helicopter
pull-up manoeuvre
rotor dynamics

Opis:

The article presents the analysis of anomaly of rotor dynamics in ultra-light helicopter - Robinson R22. Robinson R22 is two-seat, two-blade main rotor and single-engine helicopter, well known as simple and common used aircraft because of low price and high availability. At the same time, large number of accidents and strictly defined rules (recommended piloting technique) and weather condition for safe flight show disadvantages of Robinson R22. The reason for considering this topic is the analysis of different flight properties and helicopter behaviour as well as easy entering into dangerous flight manoeuvre. In the article different flight properties and loss of control during the pull-up, manoeuvre or vertical gusts of wind and mast bumping accidents were analysed. Analysis shows that problem may be caused by construction of three-hinged rotor hub, designed and patented by F. Robinson. Article presents model of rotor hub and review of main rotor and rotor hub construction in light helicopters. Because of number of accidents, caused by the unusual behaviour of Robinson R22, restrictive pilotage rules were introduced: prohibition of flight in certain weather conditions, the necessity of attending additional training conducted by trained instructors. To reduce the probability of an accident a special instruction for specific Robinson R22 properties was created. Moreover, the statistics of accidents resulting from loss of control and review of legal changes caused by Robinson R22 accidents are presented.

Źródło:

Journal of KONES; 2019, 26, 4; 235-239
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

Vibration of a mistuned three-bladed rotor under regular and chaotic excitations

Autorzy:

Warminski, J.
Latalski, J.
Szmit, Z.

Powiązania:

https://bibliotekanauki.pl/articles/280551.pdf

Data publikacji:

2018

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

rotating beam
multi-bladed rotor
rotor mistuning
chaotic oscillations

Opis:

This study considers forced vibrations of a rotating structure consisting of a rigid hub and three flexible beams. The blades are nominally made of a multilayered laminate with a specific stacking sequence resulting in full isotropic macroscopic material behaviour. However, in the performed analysis it is assumed that the rotor has been mistuned because of manufacturing tolerances of the composite material. These inaccuracies are represented by deviations of reinforcing fibres orientations from their nominal values. The considered tolerances break the intended macroscopic material isotropy and make the laminate to exhibit the fully orthotropic behaviour. Based on previous authors research, the system of four mutually coupled dimensionless ordinary differential governing equations is adopted. Forced responses of the system under regular and chaotic excitations are investigated.

Źródło:

Journal of Theoretical and Applied Mechanics; 2018, 56, 2; 549-566
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

Numerical simulation of model helicopter rotor in hover

Autorzy:

Doerffer, P.
Szulc, O.

Powiązania:

https://bibliotekanauki.pl/articles/1943245.pdf

Data publikacji:

2008

Wydawca:

Politechnika Gdańska

Tematy:

transonic
hover
helicopter rotor

Opis:

The article presents details of a URANS simulation of the flow field near a hovering model of the Caradonna and Tung (1981) helicopter rotor [1]. The CFD code SPARC [2] proves to be capable of capturing the aerodynamics of a two-bladed rotor in high-speed transonic hover conditions. A comparison of the simulation results with the experimental data is acceptable, hence the described methodology might be used with confidence in future numerical studies of application of noise-reducing devices on helicopter blades.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2008, 12, 3-4; 227-236
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Dyspersja kropel w mieszalnikach typu rotor-stator
Drop dispersion in rotor-stator mixers

Autorzy:

Jasińska, M.
Bałdyga, J.
Hall, S.
Pacek, A.

Powiązania:

https://bibliotekanauki.pl/articles/2072442.pdf

Data publikacji:

2013

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

mieszalnik rotor-stator
olej silikonowy
model multifraktalny
turbulencja
rotor-stator mixer
silicon oil
turbulence
multifractal model of turbulence

Opis:

Przedstawiona praca ma charakter doświadczalno-teoretyczny. W części doświadczalnej przeprowadzono badania rozpadu rozproszonych w wodzie kropel oleju silikonowego. Badania prowadzono w przepływowym mieszalniku typu rotor-stator (Silverson), pracującym w sposób ciągły. Modelowanie prowadzono wykorzystując oprogramowanie CFD i multifraktalny model burzliwości. Wyniki obliczeń pokazały zgodność trendów z wynikami doświadczalnymi.
The work deals with numerical and experimental investigations of drop breakup during the formation of emulsions. Silicon oil was applied to investigate drop dispersion in the in-line Silverson rotor-stator mixer. Experimental results were interpreted using CFD and the multifractal model oi intermittent turbulence. Predicted trends of influence of process parameters on drop size agree with experimental data.

Źródło:

Inżynieria i Aparatura Chemiczna; 2013, 3; 187--188
0368-0827

Pojawia się w:

Inżynieria i Aparatura Chemiczna

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 9.

Tytuł:

Two vortex interaction patterns in a turbine rotor

Autorzy:

Świrydczuk, J.

Powiązania:

https://bibliotekanauki.pl/articles/258702.pdf

Data publikacji:

2009

Wydawca:

Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa

Tematy:

secondary vortices
turbine rotor
interaction pattern

Opis:

The article analyses the unsteady interaction of vortex structures in a turbine rotor passage. In the form of sample cases, two high-pressure steam turbine stages are examined: a standard stage, used as the reference, which reveals regular performance characteristics and distributions of flow parameters, and a low-efficiency stage, in which a large separation zone is observed in the rear part of the rotor passage. In the latter case the combined interaction of all vortices has been found to take an extremely complex course and be a source of remarkable flow fluctuations. The methodology applied for extracting particular vortex structures from the general flow pattern bases on comparing entropy distributions with corresponding velocity vectors. The reported vortex interaction patterns are believed to be representative for a variety of turbine constructions of both land, and marine applications.

Źródło:

Polish Maritime Research; 2009, 2; 45-53
1233-2585

Pojawia się w:

Polish Maritime Research

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

Robust control and modal analysis of flexible rotor magnetic bearings system

Autorzy:

Mystkowski, A.

Powiązania:

https://bibliotekanauki.pl/articles/229827.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

active magnetic bearings (AMB)
uncertainty design
flexible rotor model
bending modes
synthesis control
rotor vibrations control

Źródło:

Archives of Control Sciences; 2010, 20, 2; 151-163
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

m-Synthesis control of flexible modes of AMB rotor

Autorzy:

Mystkowski, A.

Powiązania:

https://bibliotekanauki.pl/articles/386538.pdf

Data publikacji:

2010

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

wirnik
synthesis
elastyczność
rotor
synteza
flexibility

Opis:

In the paper the optimal robust vibration control of flexible rotor supported by the active magnetic bearings (AMBs) is investigated. The purpose of the control system is stabilization of the high speed rotor and effective control of the rotor vibration due to noncollocation, gyroscopic effects and model uncertainties. The noncollocation effect is considered and frequency modal analysis of the noncollocated AMBs system with gyroscopic effects is presented. The ž-Synthesis control is applied to stabilize the rigid and flexible critical frequency modes of the rotor, with emphasis structural and parametric uncer-tainty. The input and output signals in AMBs system are limited by the weighting functions. The singular value analysis is used to obtain therobust performances of the closed-loop system. The stable operation and good stiffness of the high speed rotor supported magnetically is reached. The dynamical behaviour of the AMBs rotor is evaluated in the range up to 21 000 rpm. The experimental tests show the effectiveness of the robust control system as well as good vibrations reduction and robustness of the designed controllers.

Źródło:

Acta Mechanica et Automatica; 2010, 4, 4; 83-90
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 12.

Tytuł:

2019Gyroplane rotor hubs strength tests

Autorzy:

Wojtas, Małgorzata
Sobieszek, Agnieszka

Powiązania:

https://bibliotekanauki.pl/articles/242059.pdf

Data publikacji:

2019

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

gyroplane
strength tests
rotor hub
aviation regulations

Opis:

In this article a review of rotor,hub constructions were presented. Discussed rotor’s hub ismade of composite or aluminum alloys materials. Two types of rotor hub were presented (four-blades and two-blades teetering rotor hub), each of them are dedicated to gyroplanes. Typical gyroplane main rotors are characterized by simple design, especially in case of rotors forlight gyroplanes. In the following part of the article thetype of strength tests required by certification process were shown. The test programs based on legal aspects of admission to the flight tests taking into account legislation such as CS 27 (Subpart C – Strength Requirements), CAP 643 British Civil Airworthiness requirements Section T Light gyroplanes, ASTM F2972. Furthermore, this articlediscusses strength tests of gyroplane rotor hub such as measured parameters, methodology of measurement, types of sensors, course of test, test stands, and limit loads. The loads during “pull-up from level flight” manoeuvreare limit loads during tests. Required additional processes, like averification the same parameters by two types of method were shown i.e.deformation of structure were tested by strain gauges and reverse engineering.Strength tests had to be made before flight test, based on results of them aircrafts are flight authorized. In conclusion,the results of tests were presented and fulfilment of legal assumptions and requirements were shown.

Źródło:

Journal of KONES; 2019, 26, 3; 265-270
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

Wind tunnel tests of quad-rotor autogyro model

Autorzy:

Krzysiak, A.

Powiązania:

https://bibliotekanauki.pl/articles/244321.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

transport
autogyro
quad-rotor
aerodynamic characteristics
charakterystyki aerodynamiczne

Opis:

The wind tunnel investigation of basic aerodynamic characteristics as well as flow visualization tests of the innovative quad-rotor autogyro model is presented. The wind tunnel measurements of aerodynamic characteristics were carried out using 6-component internal strain-gauge balance. In the area of the main rotor and quad-rotors, the flow visualization tests were performed by PIV (Particle Image Velocimetry) System. The work was carried out in cooperation with the Lublin University of Technology, which provided a model of gyroplane manufactured according to their own concept. In the experimental study an influence of quad-rotors as well as pusher propeller on the autogyro model characteristics were determined by measurements aerodynamic forces and moments for a number of selected model configurations. The wind tunnel experimental tests were performed in the Institute of Aviation low speed wind tunnel T-1, characterized by 1.5 m diameter test section. The investigations were carried out for undisturbed flow velocity V∞ = 12.5 m/s, which corresponds to the Reynold’s number, Re = 0.82 * 106 referred to 1 m, The angles of attack used in the experiment were implemented in two ranges -40 ≤ α \ ≤ 20 and 00≤ α ≤ 130, with a sideslip angle β = 0. The tests showed that the flow induced by quad-rotors interfered with the flow induced by the main rotor changing the autogyro aerodynamic characteristics.

Źródło:

Journal of KONES; 2017, 24, 1; 231-238
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

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Skocz do pozycji: 14.

Tytuł:

Dynamics of cellular rotor of asynchronous motor with deformable stator

Autorzy:

Morzuch, W.

Powiązania:

https://bibliotekanauki.pl/articles/127998.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Instytut Mechaniki Stosowanej

Tematy:

rotor
dynamic stability
wirnik
stateczność dynamiczna

Opis:

The analysis of the dynamic stability of cellular rotor in asynchronous motor with deformable stator has been determined. The values of magnetic tension and angular velocities of the rotor under which the loss of stability is observed has been determined. A model of rotor with continuous mass distribution and changeable rigidity has been applied in the analysis. In order to estimate the stability of the rotor the equations of its transverse vibration has been formulated. This equations connecting the dynamic deflection of rotor with space and time. Then the differential equations has been solved. On the basis of the mentioned equations the values of magnetic tension and angular velocities of the rotor under which the loss stability is observed, have been determined.

Źródło:

Vibrations in Physical Systems; 2014, 26; 177-182
0860-6897

Pojawia się w:

Vibrations in Physical Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

Power characteristics of inline rotor-stators with different head designs

Autorzy:

Hannam, Alex
Sparks, Trevor
Özcan-Taşkın, N. Gül

Powiązania:

https://bibliotekanauki.pl/articles/2034042.pdf

Data publikacji:

2021

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

in-line rotor-stators
power characteristics
rotor-stator design
charakterystyka mocy
wirnik

Opis:

n-line rotor-stators are widely used for power intensive industrial applications, such as deagglomera- tion, emulsification. There is limited information on characteristic power numbers for different designs which can be used to calculate the average power input as a means to evaluate process performance. This study made use of 18 different rotor-stators, 17 of which were toothed designs with different geometry, and also a commercially available design, with the objectives of evaluating the applicability of different expressions for characteristic power numbers and establishing the effects of geometric variations on the power input. The expression P = Po1 ρN3 D5 + Po2 ρN2 D2Q is found to account for the experimental data over a wide range of operating conditions. Rotor diameter was found to have the most prominent effect on the power input: an increase in rotor diameter from 119.6 to 123.34 mm resulted in an increase in the average power draw. The effect of rotor diameter examined with geometrically similar set ups reducing the diameter from 123.34 to 61.44 mm, for which the mixing chamber was also proportionately smaller, showed a decrease in the power input at a given speed and flowrate as well. The effects relating to the percentage of open area of the stator and number of rotor teeth were less obvious. Increasing the open area resulted in an increase in the power input – an effect which could be observed more clearly as the flowrate (1 to 4 l/s) and rotor speed (at 2000 and 3000 rpm) were also increased. Increasing the number of stator teeth increased the power input and this effect was more prominent when operating at the highest rotor speed of 3000 rpm and at low flowrates (1–2 l/s).

Źródło:

Chemical and Process Engineering; 2021, 42, 2; 91-104
0208-6425
2300-1925

Pojawia się w:

Chemical and Process Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Control-oriented modelling and control of rotor vibration

Autorzy:

Gosiewski, Z.

Powiązania:

https://bibliotekanauki.pl/articles/387200.pdf

Data publikacji:

2008

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

drgania wirnika
tłumienie drgań
rotor vibration
vibration damping

Opis:

Deep analysis of the control plant brings many useful information for the designer of the control system. The analysis is also important part in the design of active vibration control system. The coupling of different dynamical phenomena in rotating machinery leads to unstable vibrations. Usually, the coupling effects are caused by changing parameters. Angular speed or rotor unbalance in some applications are such parameters which change in the wide range. The problem is to find for which angular speeds we have unstable torsional/lateral vibrations. Usually, the unstable regions are in the vicinity of angular speeds where maps of natural frequencies for both dynamical systems cross each other. In the paper there was explained which intersection of torsional and lateral natural frequencies are unstable and why. The root locus method was used to explain the phenomenon. It indicated such control procedures which amplify the positive (stabilizing) mechanisms in the rotor dynamics. Such procedures can also lead to the energy saving control laws. In the case of lateral vibrations there were considered four control strategies. And these strategies were compared to indicate optimal one.

Źródło:

Acta Mechanica et Automatica; 2008, 2, 2; 21-38
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

Modelling of helicopter main rotor aerodynamic loads in manoeuvres

Autorzy:

Kowaleczko, Grzegorz
Leśniczak, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/241695.pdf

Data publikacji:

2019

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

helicopter
main rotor
aerodynamic loads

Opis:

The article discusses the method of modelling of the helicopter main rotor aerodynamic loads during steady state flight and manoeuvres. The ability to determine these loads was created by taking into account the motion of each blade relative to the hinges and was a result of the applied method of aerodynamic loads calculating. The first part of the work discusses the basic relationships that were used to build the mathematical model of helicopter flight. The focus was also on the method of calculating of the aerodynamic forces generated by the rotor blades. The results of simulations dedicated to the "jump to hover" manoeuvre were discussed, showing the possibilities of analysing aerodynamic loads occurring in unsteady flights. The main rotor is considered separately in an “autonomous” way and treated as a source of averaged forces and moments transferred to the hub. The motion of individual blades is neglected, and their aerodynamic characteristics are radically simplified. The motion of individual blades is neglected, and their aerodynamic characteristics are radically simplified. This can lead to significant errors when attempting to model dynamic helicopter manoeuvres. The more complex model of helicopter dynamics is discussed.

Źródło:

Journal of KONES; 2019, 26, 4; 273-284
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

Vibration testing of a helicopter main rotor composite blade
Próby wibracyjne kompozytowej łopaty wirnika śmigłowca

Autorzy:

Parafiniak, M.
Skalski, P.

Powiązania:

https://bibliotekanauki.pl/articles/212647.pdf

Data publikacji:

2011

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

próby rezonansowe wirników
kompozytowe elementy wirnika
rotor vibration tests
composite rotor elements

Opis:

The research presented in this paper focuses on a composite structure test. The object of the investigation is a blade from main rotor of the IS-2 helicopter. The basic methodology which is used is the Experimental Modal Analysis (EMA). The EMA technique is an established tool for the identification of dynamic properties of structure. Based on the experimental data collection, dynamic properties of a research object were estimated. The modal parameters have been estimated using PolyMAX – module of LMS Test.Lab software.
Badania przedstawione w pracy odnoszą się do prób struktury kompozytowej. Badany obiekt to kompozytowa łopata wirnika śmigłowca IS-2. Metoda badawcza jaka została użyta w próbach to eksperymentalna analiza modalna (ang. EMA). Technika ta jest uznanym narzędziem do identyfikacji własności dynamicznych konstrukcji. Na podstawie danych eksperymentalnych, własności dynamiczne zostały wyznaczone, za pomocą PolyMAX – modułu programu LMS Test.Lab.

Źródło:

Prace Instytutu Lotnictwa; 2011, 9 (218); 72-76
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 19.

Tytuł:

Rozkład pola prędkości strumienia zawirnikowego wirnika nośnego oraz śmigła ogonowego śmigłowców - badania eksperymentalne
The distribution of the behind-rotor flux velocity field main rotor and a tail rotor of a helicopters - experimental studies

Autorzy:

Łusiak, T.

Powiązania:

https://bibliotekanauki.pl/articles/212986.pdf

Data publikacji:

2011

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

rozkład pola prędkości wirnika
śmigło ogonowe śmigłowców
badania eksperymentalne
tests and research
distribution of the behind-rotor flux
tail rotor of a helicopters
experimental studies

Opis:

W pracy przedstawiono wyniki badań eksperymentalnych wartości prędkości indukowanej w bliskim otoczeniu śmigłowca. Badania przeprowadzono na obiektach rzeczywistych śmigłowców EC-135P2 oraz Mi-2. Dokonano próby stwierdzenia poprawności przeprowadzonej analizy numerycznej opisanych przypadków w pracy Wojciecha Florczuka pt: „Analiza operowania śmigłowca EC135P2 nad obszarem lotniska”. Do badań wykorzystano przenośnej aparatury pomiarowej – zestaw anemometryczny typu AZ8901.
The paper presents the experimental results on the values of the induced velocity in close surrounding to a helicopter. The study was carried out on the real helicopters, i.e. EC-135P2 and Mi-2. The attempts were to verify the correctness of the numerical analysis of the study cases reported in the work by Wojciech Florczuk „The analysis of operating the EC135P2 helicopter over an airport area”. A portable measuring apparatus, i.e. the AZ8901 anemometric set was used for the research.

Źródło:

Prace Instytutu Lotnictwa; 2011, 10 (219); 240-246
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Influence of rotor parameter changes on helicopter performance and the main rotor load level
Wpływ zmian parametrów wirnika na osiągi śmigłowca oraz poziom obciążeń wirnika

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/212387.pdf

Data publikacji:

2015

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

helicopter
rotor
performance
śmigłowiec
wirnik
osiągi

Opis:

Paper presents the results of calculations revealing the influence of changes the main rotor significant parameters like number of blades and rotational speed on helicopter performance and on rotor loads. The level of noise for rotor operated in hover condition is estimated. The rotor loads are defined applying simulation program which includes model of deformable blade. A Runge-Kutta method is used to solve the equations of motion of the elastic blade.
Przedstawiono efekty zmian podstawowych parametrów wirnika nośnego, jak liczba łopat i prędkość obrotowa wirnika na osiągi śmigłowca oraz na obciążenia wirnika nośnego. Zamieszczono przybliżoną ocenę wpływu zmian własności wirnika na poziom generowanego hałasu. Obciążenia wirnika wyznaczano metodą symulacyjną przy wykorzystaniu programu uwzględniającego model odkształcalnej łopaty. Do rozwiązania równań ruchu elastycznej łopaty zastosowano metodę Runge-Kutta.

Źródło:

Prace Instytutu Lotnictwa; 2015, 1 (238); 54-69
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

Innovative composite gyroplane rotor blades : fatigue tests

Autorzy:

Wojtas, M.
Sobieszek, A.
Szczepanik, T.

Powiązania:

https://bibliotekanauki.pl/articles/241581.pdf

Data publikacji:

2018

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotor blades
fatigue tests
NDT
composite

Opis:

The paper presents test bench method for verifying the fatigue life of the rotor blades, working in operating conditions in a position steady flight (autorotation), on the aviation construction called the gyroplane. One of the critical elements of this design is the main rotor, which in its modern versions takes the form of advanced composite structures subjected to loads in flight complex variable, the nature of which differs from the well-known operating conditions of helicopter rotors. The article includes a description of the test object, which are composite rotor blades designed specifically to work in autorotation, the specificity of loads of autorotation rotor, and method of implementation of the gyroplane rotor work cycles in the test bench. The main aim of this research is to evaluate the sustainability of the composite blades under the gyroplane operating loads with the goal to allow the rotor to operate in the air. The tests were carried out for 100 hours of gyroplane flight at loads do not exceed the maximum operating loads, and for several hours under a load higher than operating. During test for the evaluation of composite structure, the infrared camera with dedicated software IRNDT was used. The reached showed structural integrity in critical mounting section of the blade.

Źródło:

Journal of KONES; 2018, 25, 4; 447-453
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 22.

Tytuł:

Prototype test stand for testing insolated rotor systems

Autorzy:

Wojtas, Małgorzata
Czajkowski, Łukasz

Powiązania:

https://bibliotekanauki.pl/articles/242886.pdf

Data publikacji:

2019

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

test stand
main rotor
design
construction resonance

Opis:

The article discusses assumptions for a prototype test stand designed for testing rotors in the conditions of work at their nominal speed, in particular gyrocopter and helicopter rotors. In the work presents an overview of similar solutions of test stand presented in the available literature and solutions proposed by companies, such as Swangate International or Luftfahrttechnik GmbH. Beyond these solutions the article also contains test stand used so far at the Institute of Aviation, these solutions were prepared for testing one type of rotor (for example: only for gyroplane rotors). The article provides the steps of designing a new test stand, which one of the basic assumptions is that it will be a universal test stand, giving the possibility to test different types of rotors. The article discusses two concepts of the stand with electric engine as a drive, gives the advantages and disadvantages of each concept, and indicates the selected solution. In addition to design and applied drive solution of the stand, the measuring part and data acquisition were also discussed. Moreover, the article focus on the advantages of rotor testing using the presented solution, as well as problems encountered during tests, in particular related to construction free vibrations and resonance. Vibration and resonance of the test stand are very important aspect of the entire design process, because it affects the quality and safety of the tests.

Źródło:

Journal of KONES; 2019, 26, 3; 257-264
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 23.

Tytuł:

New gyroplane hub connector with positive coning angle

Autorzy:

Wojtas, M.
Trendak, M.

Powiązania:

https://bibliotekanauki.pl/articles/244662.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

blade dihedral angle
waving
rotor instability
teetering rotor

Opis:

The article presents advantages and disadvantages of two blade teetering rotors with constructional dihedral angle greater than 0o . Several structural design solutions of rotor hub connector are shown in this work. However, the main attention is focused on innovative hub connector design and manufactured by Trendak Aviation Company during the project “Research and development works on innovative construction of aircrafts of weight over 560 kilograms”. Discusses structural advantages of the new rotor hub connector according to other construction. Also were raised issues related to the load of the gyroplane rotor during the flight, in particular the load of rotor blades root, during a gyroplane break manoeuvre, according to conning angle of rotor hub connector. The disadvantages of using the structural dihedral angle in teetering rotors are also presented, focusing on the rotor aeroelastic instability so-called waving, which from the literature analysed is concerned only with two blades teetering rotors. Performed a coarse analysis in SMOG program, prepared at the Institute of Aviation for the analysis of helicopter and gyroplanes rotors. The stability analysis of the rotor for a number of structural dihedral angle and blades setting pitch was performed. Basis of this analysis the stability boundary were determined for the analysed gyroplane rotor with connector hub with positive coning angle of 2.8o. .

Źródło:

Journal of KONES; 2017, 24, 3; 325-330
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 24.

Tytuł:

Głowica wiatrakowca IL-28 umożliwiająca pionowy start
Rotor head of gyroplane with vwrtical take off posibil

Autorzy:

Delega, M.

Powiązania:

https://bibliotekanauki.pl/articles/212937.pdf

Data publikacji:

2009

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

awionika
osprzęt lotniczy
głowica wiatrakowca IL-28
start pionowy
avionics
rotor head
rotor head of gyroplane

Opis:

W artykule przedstawiono projekt głowicy do wiatrakowca projektowanego w Instytucie Lotnictwa, w ramach grantu współfinansowanego przez Unię Europejską.
Following publication shows the design of gyroplane head designing by Institute of Aviation under grant supported by European Community.

Źródło:

Prace Instytutu Lotnictwa; 2009, 7 (202); 18-23
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 25.

Tytuł:

Unsteady flow through the gap of savonius turbine rotor

Autorzy:

Świrydczuk, J.
Doerffer, P.
Szymaniak, M.

Powiązania:

https://bibliotekanauki.pl/articles/1934037.pdf

Data publikacji:

2011

Wydawca:

Politechnika Gdańska

Tematy:

Savonius turbine
rotor gap
vortices

Opis:

The paper presents a numerical analysis of unsteady flow through the gap of a Savonius turbine rotor, performed for varying integral turbine operating parameters calculated for the case under study as well as obtained from experiments described in the literature. Changes in the unsteady flow pattern, including the development and interaction of numerous vortex structures in the vicinity of the gap, and their relevance to the varying integral parameters are discussed. We conclude that the structure responsible for the intensity of the flow through the gap is a vortex which forms in the vicinity of the gap at certain phases of rotor revolution, and that a possible way to improve the efficiency of operation of a Savonius turbine is to control the intensity of this vortex by modifying the shape of the blade edges in the vicinity of the gap.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2011, 15, 1; 59-70
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 26.

Tytuł:

Rotor fault compensation and detection in a sensorless induction motor drive

Autorzy:

Bednarz, S.

Powiązania:

https://bibliotekanauki.pl/articles/1193283.pdf

Data publikacji:

2017

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

rotor faults
DFOC
speed estimator
MRAS
parameter estimator

Opis:

The compensation and detection analysis of rotor faults in a sensorless induction motor drive system with an additional rotor resistance estimator has been conducted and the influence of the rotor faults on the properties of such system has been examined. The rotor flux vector and rotor speed have been reconstructed by the MRASCC estimator. The drive was tested for various conditions. Simulation tests were performed in the direct field oriented control (DFOC) structure realized in the MATLAB/Simulink software.

Źródło:

Power Electronics and Drives; 2017, 2, 37/1; 71-80
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

Rotor turbulence influence on helicopter flights in high urban built-up area

Autorzy:

Łusiak, T.
Grudzień, A.

Powiązania:

https://bibliotekanauki.pl/articles/103088.pdf

Data publikacji:

2013

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

helicopter
rotor
turbulence
urban area

Opis:

The paper provides a discussion of the influence of turbulence in the areaa of high urban buildings or in vicinity of fire on safety of helicopter flights. The analysis was conducted using Ansys Fluent software. All the threats considering helicopter flight, landing and hovering in such an environment were shown. As objects of this research helicopter types: W3-A Sokół, W3-A Głuszec and Robinson R-44 were used.

Źródło:

Advances in Science and Technology. Research Journal; 2013, 7, 17; 47-50
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 28.

Tytuł:

Design and optimisation of main rotor for ultralight helicopter

Autorzy:

Stalewski, W.

Powiązania:

https://bibliotekanauki.pl/articles/243641.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotorcraft
ultralight helicopter
main rotor
airfoil
computer-aided design
optimisation

Opis:

A modern main rotor, dedicated to the ultralight helicopter, has been designed and optimised. Due to assumed simplicity of the rotor design and taking into account some technological constraints, the principal purpose of the presented research was to design a dedicated airfoil which, when applied on the main-rotor blades, would influence satisfactory improvement in a performance of the ultralight helicopter, especially in fast flight. The design and optimisation process has been supported by a computational methodology. The in-house software has been used for direct and inverse design of shapes of the rotor-blade airfoils. Aerodynamic properties of the airfoils as well as the helicopter main rotor were evaluated based on both the two-dimensional and three-dimensional flow simulations conducted using the ANSYS FLUENT software that was used to solve U/RANS equations. Based on the results of conducted computational simulations of fast flight of the ultralight helicopter, it can be concluded that the newly designed main rotor, compared to the baseline, may give certain improvement in helicopter performance in fast flight. In addition, the application of this newly designed rotor may lead to increase of a maximum speed of the helicopter flight, due to the greater lift force achievable by this rotor on the retreating blade, which is favourable from point of view of keeping of a lateral balance of the helicopter in fast flight.

Źródło:

Journal of KONES; 2017, 24, 4; 287-295
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Diagnosing of rotor systems of marine gas turbine engines in nonstationary states

Autorzy:

Grządziela, A.

Powiązania:

https://bibliotekanauki.pl/articles/246906.pdf

Data publikacji:

2010

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

dynamics
gas turbines
rotor vibration
run-up process

Opis:

Vibration tests of marine gas turbine engines are performed as researches on-line and off-line types. Systems on-line type generally monitored one or two vibration symptoms, which asses the limited and/or the critical values of parameters and they potentially can warn and/or shutdown engines. Systems off-line types are usually used for vibration analyzing during non-steady state of work. The paper presents comparison of different methods of analyzing vibration symptoms measured under run-up and shut-down processes of marine gas turbine engines. Results of tests were received on gas turbine engine DR76 type of the COGAG type propulsion system. The engine was not fitted with vibration monitoring system. Main goal of researches was qualified of help fulness and unequivocally results received by methods of synchronous measurement, order tracking and auto tracking. All vibration symptoms were chosen from the methodology of the diagnosing gas turbine engines operated in the Polish Navy, called BDS (Base Diagnosing System). Second purpose was estimation of the possibility of implementation presented methods of vibration analyses of gas turbine engines for on-line monitoring system. Application of periodical or on-line diagnostic procedures makes it possible to operate ship propulsion systems in accordance with their current technical state. The realization of the investigations made reliable verification of the investigation results possible.

Źródło:

Journal of KONES; 2010, 17, 2; 121-127
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

Performance requirements and simulation of rotor operation for high-mountain rescue helicopter

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/243448.pdf

Data publikacji:

2018

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rescue helicopter
high-mountain operations
rotor blade deformation

Opis:

Simulation results concerning performance of helicopter suitable for high-mountain rescue operations are presented. Including operations in regions of the highest Himalaya Mountains, the possibility of hover ceiling out of ground effect (OGE) at 10,000 m above sea level is assumed. Demand of high ratio of developed lift to power required for hover leads to choice the coaxial rotor configuration as the best for rescue helicopter, which can operate in extremely high mountain environment, and gives good stability features in wind gust conditions in comparison with single main rotor helicopter. For performance calculations the simple model of helicopter is applied, which consists of fuselage point mass and rotor disk. The cases of partial and total power loss are considered to define range of H-V zones and possibilities of flight continuation due to height of landing surface over level of sea. The rotor blades and rotor loads are calculated applying detail model of elastic blade, which includes effects of its deflections due to out-of-plane bending, in plane bending, and torsion. The Runge-Kutta method is applied to solve equations of motion of rotor blades with taken into account effects of blade pitch control and variable deflections of blades. According to Galerkin method, the blade parameters of motion are treated as a combination of torsion and bending eigen modes of the rotor blades. Elastic blade model allows defining behaviour rotor blades in selected states of flight: hover, level flight, wind gust conditions, and pull-up manoeuvre. The results of simulation for upper and lower rotor for blade deflections and loads are shown in form of time-run plots and rotor disk distributions. The simulation investigation may be applied to define features of helicopter configuration suitable for operation in extremely high mountain conditions..

Źródło:

Journal of KONES; 2018, 25, 2; 341-348
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 31.

Tytuł:

Analysis of technological process of installation turbochargers

Autorzy:

Cygnar, M.
Mazurków, A.
Jaskólski, J.

Powiązania:

https://bibliotekanauki.pl/articles/244108.pdf

Data publikacji:

2008

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

turbocharger
installation of turbocharger's group
turbine's rotor
compressor's rotor

Opis:

The technological process of installation of turbocharger as well as detailed analysis of chosen stages of installation having fundamental influence on the correct work of the turbocharger are presented in the article. The purpose of this article is performance of whole process of installation turbocharger as well as analysis of particularly significant stages of this process. The creature of turbocharging and it is myself this of working of turbocharger is enough simple. Difficulties appear if we put to the analysis conditions work of turbocharger: high temperature offumes, variable loads, aggressive environment of combustion gases, high rotatory speeds of rotors. Some of exploitation problems are possible to the elimination on the design stage or by means of application of appropriate materials. However technological process of installation is responsible for output quality and failure-free lasting work of turbocharger. In the process of installation it can distinguish some essential stages: processing and installation of shaft with the turbine's rotor, the weighing of turbine's rotor and the compressor, the installation of rotor's group, weighing of rotor's group in the trunk, positional tests under load. High rotary speeds cause during work of rotator so that created during of installation of turbocharger inappropriate balancing can bring to important damages of turbocharger. The correct course of process of installation and the final verification on braked position allows to avoid most of breakdowns of turbocharger group as well as to ensure long term of correct exploitation.From this reason very important is detailed analysis of respective stages of installation of group.

Źródło:

Journal of KONES; 2008, 15, 2; 35-39
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Empirical Tests of Stress in Gyroplane Rotor During Flight

Autorzy:

Czarnigowski, Jacek

Powiązania:

https://bibliotekanauki.pl/articles/102254.pdf

Data publikacji:

2020

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

gyroplane
rotor blade
hub bar
stress
łopata wirnika
pręt piasty
naprężenie

Opis:

The paper presents the results of experimental investigations of total tensile stresses in a gyroplane’s rotor during flight. The research aimed to determine which flight maneuvers induce the greatest stress in the rotor blade and the hub bar. The object of research was an ultralight gyroplane Tercel by Aviation Artur Trendak equipped with a rotor by the same manufacturer. Measurements were taken a) at the root of the rotor blade in the longitudinal direction, at the rotor blade’s lower surface in the point where the blade is attached to the hub bar, and b) in the hub bar, on its lower surface also in the longitudinal direction. To measure the stress, the author constructed an original measuring system based on the strain gauge bridge circuit mounted on the rotor head. The tests were carried out in a wide range of maneuvers within the gyroplane’s flight envelope. The highest value of tensile stress was found to occur while rapidly reducing the horizontal velocity in steep descent.

Źródło:

Advances in Science and Technology. Research Journal; 2020, 14, 3; 107-117
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Rotor dynamics - four open questions

Autorzy:

Kiciński, Jan

Powiązania:

https://bibliotekanauki.pl/articles/2090686.pdf

Data publikacji:

2021

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

rotor dynamics
non-linear models
prehistory
heuristic modelling
dynamika wirnika
dynamika nieliniowa
prehistoria
modelowanie heurystyczne

Opis:

Despite many years of development in the field of rotor dynamics, many issues still need to be resolved. This is due to the fact that turbomachines, even those with low output power, have a very complex design. The author of this article would like to signal these issues in the form of several questions, to which there are no precise answers. The questions are as follows: How can we build a coherent dynamic model of a turbomachine whose some subsystems have non-linear characteristics? How can we consider the so-called prehistory in our analysis, namely, the relation between future dynamic states and previous ones? Is heuristic modelling the future of rotor dynamics? What phenomena may occur when the stability limit of the system is exceeded? The attempt to find answers to these questions constitutes the subject of this article. There are obviously more similar questions, which encourage researchers from all over the world to further their research.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 6; e139791, 1--10
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Design and Strength Analysis of Curved-Root Concept for Compressor Rotor Blade in Gas Turbine

Autorzy:

Wdowiński, W.
Szymczyk, E.
Jachimowicz, J.
Moneta, G.

Powiązania:

https://bibliotekanauki.pl/articles/97975.pdf

Data publikacji:

2017

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

finite element method
turbine engine
rotor disk
rotor blades
blade-disc connection
shape optimization

Opis:

The motivation of the article is fatigue and fretting issue of the compressor rotor blades and disks. These phenomena can be caused by high contact pressures leading to fretting occurring on contact faces in the lock (blade-disk connection, attachment of the blade to the disk). Additionally, geometrical notches and high cyclic loading can initiate cracks and lead to engine failures. The paper presents finite element static and modal analyses of the axial compressor 3^rd for the original trapezoidal/dovetail lock geometry and its two modifications (new lock concepts) to optimize the stress state of the disk-blade assembly. The cyclic symmetry formulation was used to reduce modelling and computational effort.

Źródło:

Fatigue of Aircraft Structures; 2017, 9; 137-155
2081-7738
2300-7591

Pojawia się w:

Fatigue of Aircraft Structures

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

Control of anisotropic rotor vibration using fractional order controller

Autorzy:

Czajkowski, M.
Gertner, M.
Ciulkin, M.

Powiązania:

https://bibliotekanauki.pl/articles/280540.pdf

Data publikacji:

2016

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

rotor dynamic
active bearings
fractional order controller

Opis:

This article presents an analysis of a flexible Jeffcott rotor with an active bearing support. The rotor is coupled with lateral and torsional vibrations and a force from the unbalance vector derived from the Lagrangian method. The active support bearing is controlled by FOPID controller. Changing the rotor vibration is followed by shifting rotor angular speed and achieving the natural frequency. Simulation results demonstrate torsional and lateral vibration of thr rotor at the rotating speed near the natural frequency. Consequently, controlling the lateral vibrations mitigates potential damage and improves safety. FOPID controller introduces a new approach to vibration control of a rotating machine.

Źródło:

Journal of Theoretical and Applied Mechanics; 2016, 54, 3; 1013-1024
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

Tytuł:

Bifurcation and chaos analysis of a gear-rotor-bearing system

Autorzy:

Gou, X.
Zhu, L.
Qi, C.

Powiązania:

https://bibliotekanauki.pl/articles/281909.pdf

Data publikacji:

2018

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

gear-rotor-bearing
dynamics
bifurcation
chaos

Opis:

To study chaos and bifurcation of a gear system, a five-degree-of-freedom nonlinear dynamic model of a gear-rotor-bearing system is established. It consists of a gear pair, supporting shafts, bearings and other auxiliary components. The effects of frequency, backlash, bearing clearance, comprehensive transmission error and stiffness on nonlinear dynamics of the system are investigated according to bifurcation diagrams, phase portraits and Poincar´e maps by a numerical method. Some nonlinear phenomena such as grazing bifurcation, Hopf bifurcation, inverse-Hopf bifurcation, chaos and coexistence of attractors are investigated. Different grazing bifurcations and their causes are discussed. The critical parameters are identified, too.

Źródło:

Journal of Theoretical and Applied Mechanics; 2018, 56, 3; 585-599
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 37.

Tytuł:

Rotor Crack Detection Approach Using Controlled Shaft Deflection

Autorzy:

Kulesza, Z. S.

Powiązania:

https://bibliotekanauki.pl/articles/386800.pdf

Data publikacji:

2012

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

dynamika
diagnostyka
wirnik
pęknięcie
rotor dynamics
shaft crack
strucutre health monitoring

Opis:

Rotating shafts are important and responsible components of many machines, such as power generation plants, aircraft engines, machine tool spindles, etc. A transverse shaft crack can occur due to cyclic loading, creep, stress corrosion, and other mechanisms to which rotating machines are subjected. If not detected early, the developing shaft crack can lead to a serious machine damage resulting in a catastrophic accident. The article presents a new method for shaft crack detection. The method utilizes the coupling mechanism between the bending and torsional vibrations of the cracked, non/rotating shaft. By applying an external lateral force of a constant amplitude, a small shaft deflection is induced. Simultaneously, a harmonic torque is applied to the shaft inducing its torsional vibrations. By changing the angular position of the lateral force application, the position of the deflection also changes opening or closing of the crack. This chang/ es the way the bending and torsional vibrations are being coupled. By studying the coupled lateral vibration response for each angular position of the lateral force one can assess the possible presence of the crack. The approach is demonstrated with a numerical finite element model of a rotor. The results of the numerical analysis demonstrate the potential of the suggested approach for effective shaft crack detection.

Źródło:

Acta Mechanica et Automatica; 2012, 6, 4; 32-40
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

A simulation analysis of behaviour of ship-borne helicopter main rotor due to ship motion

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/243038.pdf

Data publikacji:

2016

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

helicopter
rotor blade
ship deck operation

Opis:

The paper presents a simulation method of analysis of the couplings between rotor blades motion and helicopter fuselage standing on ship deck at the phase of take-off or landing when whirling rotor generates thrust less than weight of the helicopter. The oscillating motion of the ship deck due to waves is considered. The physical model includes the helicopter fuselage treated as the stiff body supported by units of springs and dampers corresponding to landing gear characteristics. The rotor blades are modelled by elastic axes with distributed lumped masses of blade segments. The equations of fuselage and rotor blades motion are solved applying Runge-Kutta method. According to the Galerkin method, parameters of rotor blades motion are assumed as a resultant combination of considered blade torsion and bending eigen modes. Data of the light helicopter with three-bladed rotor are applied for the simulation of the rotorcraft behaviour aboard the ship. The calculations concerning helicopter standing on the fixed plane and on oscillating ship deck show influence of ship movement on fuselage motion and rotor blades deflections, flapping, and lead-lag motion. Moreover, simulations show influence of the side wind and control of the rotor swash-plate deflections. The additional unit of blade eigen modes and frequencies is applied to model the blade hitting to the flapping limiter, which can occur at the low rotation speed of the rotor. Temporary contact of the articulated blade with limiter changes its boundary conditions, which can rapidly increase the blade bending moments. The simulation method enables to determine conditions of safe operations of ship-borne helicopters without exceeding the limits and generating the excessive blade loads.

Źródło:

Journal of KONES; 2016, 23, 1; 313-320
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

Wykrywanie uszkodzenia wirnika silnika indukcyjnego z wykorzystaniem adaptacyjnego estymatora rezystancji
Detection of the induction motor rotor fault using adaptive parameter estimator

Autorzy:

Bednarz, S.

Powiązania:

https://bibliotekanauki.pl/articles/2056383.pdf

Data publikacji:

2018

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel

Tematy:

silnik indukcyjny
uszkodzenie wirnika
estymator rezystancji wirnika
MRAS
DFOC
induction motor
rotor fault
rotor resistance estimator

Opis:

W artykule omówiono możliwość wykrywania uszkodzenia prętów klatki wirnika silnika indukcyjnego z wykorzystaniem metody opartej na identyfikacji parametrów. Technika ta bazuje na założeniu, że wybrane uszkodzenia mogą objawiać się zmianami parametrów silnika, a ich estymacja i obserwowanie tych zmian pozwala na wczesną identyfikację uszkodzenia. Przy czym, w przypadku pęknięcia prętów klatki wirnika, objawem może być wzrost rezystancji schematu zastępczego wirnika. W zaproponowanym podejściu do estymacji rezystancji wirnika wykorzystano układu adaptacyjny z modelem odniesienia (MRAS). Badania silnika indukcyjnego przeprowadzono w bezpośredniej polowo-zorientowanej strukturze sterowania wektorowego. W artykule przedstawiono wyniki badań symulacyjnych, ktore wykonano w środowisku MATLAB/Simulink.
This paper deals with the broken rotor bars detection in squirrel-cage induction motor using parameter identification approach. This technique is based on the assumption, that the chosen failures may result in motor parameters variations. Estimation and observation of parameters changes allows to incipient fault detection. In the case of broken rotor bars, increase of the rotor resistance value may be a good fault symptom. In the proposed system, the rotor resistance estimator is based on the model reference adaptive system (MRAS). The induction motor is operating in the direct field-oriented control structure, under different conditions. Simulation results are performed in MATLAB/Simulink software.

Źródło:

Maszyny Elektryczne: zeszyty problemowe; 2018, 2, 118; 107--111
0239-3646
2084-5618

Pojawia się w:

Maszyny Elektryczne: zeszyty problemowe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

Niepewność danych wejściowych dotyczących obciążeń w modelowaniu układów wirnikowych
The input data uncertainty concerning loads in the rotor system modelling

Autorzy:

Pietkiewicz, P.

Powiązania:

https://bibliotekanauki.pl/articles/329132.pdf

Data publikacji:

2007

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

wirnik
niepewność danych
trajektoria
drgania
układ wirnik-łożyska
rotor
data uncertainty
trajectory
vibrations
rotor-bearings system

Opis:

W artykule przedstawiono ideę uwzględniania niepewności danych wejściowych w modelowaniu układów wirnik-łożyska w maszynach wirnikowych. Przedstawione zostały wybrane rezultaty obliczeń przy zastosowaniu dwóch różnych algorytmów generowania losowego przebiegu zmienności siły poprzecznej obciążającej wał wirnika. Wyniki wstępnych badań numerycznych pozwalają na potwierdzenie przydatności wykorzystywanych narzędzi, jednak sygnalizują także występujące trudności w interpretacji otrzymywanych tą drogą odpowiedzi analizowanych układów.
The idea of the allowance method for the input data uncertainties in the turbo-machines rotor-bearings systems modelling are contained in the paper. The author presents selected calculation results, when two different generation algorithms of the random variability course of the shear force, that imposes the rotor shaft loading, have been applied. The initial numerical research results displayed i this paper allow for acknowledge of such tools' kind usability, however they also signal the difficulties occuring in the interpretation of the analysed systems answers, received this way.

Źródło:

Diagnostyka; 2007, 3(43); 75-82
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

Aerodynamic analysis of wind turbine rotor blades

Autorzy:

Martinez, J.
Doerffer, P.
Szulc, O.
Tejero, F.

Powiązania:

https://bibliotekanauki.pl/articles/1938637.pdf

Data publikacji:

2015

Wydawca:

Politechnika Gdańska

Tematy:

aerodynamics
CFD
NREL Phase VI rotor
wind turbine

Opis:

One of the main achievements of the PLGrid Plus project is the implementation of new tools and services designed for the numerical prediction of the aerodynamic performance of wind energy turbines. An innovative and unique integration tool (Aero-T) is aiming at automating all stages (pre-, solution and post-processing) of the numerical simulation of the flow around wind turbine rotor blades using commercial CFD software based on the RANS approach and block-structured computational grids. The FINE/Turbo package (Numeca Int.) is applied in the structured grid generation process and solution phases, while the analysis of results is left to the Tecplot 360 (Tecplot Inc.) software. A demonstrator based on the NREL Phase VI rotor experiment (conducted at NASA Ames) is introduced to prove the excellent prediction capabilities of Aero-T.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2015, 19, 2; 129-140
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 42.

Tytuł:

Numerical simulation of vortex ring state phenomenon for the Mi2 type helicopter tail rotor

Autorzy:

Zalewski, W.

Powiązania:

https://bibliotekanauki.pl/articles/245648.pdf

Data publikacji:

2016

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

air transport
helicopters
tail rotor VRS

Opis:

The paper presents computational simulations of loss of helicopter tail rotor effectiveness (LTE) effect caused by rotor vortex ring state (VRS) phenomenon. The phenomenon is critical for safety of helicopter operations and it was an important factor in some military and civil helicopters serious accidents. Analysis was conducted on the example of the tail rotor of Mi2 and PZL Kania single main rotor medium helicopters, which are still in wide use in some parts of the world. That kind of dual blades tail rotor was designed with symmetrical NACA0012 airfoil. Full three-dimensional analysis of the flow around real geometry of the rotor blades was conducted by application of commercial solver Ansys Fluent. The simulation was made by resolving Unsteady Reynolds Averaged Navier Stokes equations by finite volume method with use of Moving Mesh and Moving Reference Frame techniques. A hover turn over a spot was chosen as flight condition of helicopter, which could induce the LTE phenomenon. Thrust and power consumption were estimated during computations. Visualization of the flow field and pathlines of the flow were presented for chosen stages of vortex ring formulation around the rotor. The sensitivity of dual blades tail rotors, which are popular in light and medium type of helicopters to LTE phenomenon, was estimated.

Źródło:

Journal of KONES; 2016, 23, 2; 437-442
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 43.

Tytuł:

Analysis of coupling mechanism in lateral/torsional rotor vibrations
Analiza mechanizmu sprzęgającego drgania giętno-skrętne wirnika

Autorzy:

Gosiewski, Z.

Powiązania:

https://bibliotekanauki.pl/articles/280746.pdf

Data publikacji:

2008

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

rotor
coupled vibrations
stability
root locus

Opis:

Coupling phenomena of lateral-torsional vibrations in rotating machinery can lead to rotor unstable behaviour. In some types of rotating machinery, the angular speed is subjected to wide ranges of change. The problem is to find the range of angular speeds for which a machine exhibits stable behaviour in the presence of the coupling of dynamical modes. Usually, unstable regions are in the vicinity of angular speeds where maps of natural frequencies for both dynamical systems intersect with each other. Using the root locus method, it is described which intersections lead to unstable vibrations and why.
Zjawisko sprzęgania się drgań giętnych i skrętnych w maszynach wirnikowych może prowadzić do niestabilnego ruchu wirnika. W niektórych maszynach wirnikowych prędkość obrotowa wirnika zmienia się w szerokim zakresie. Zadaniem jest znalezienie takich zakresów prędkości obrotowej, dla których ruch wirnika pozostaje stabilny mimo sprzęgania się jego postaci drgań. Zwykle niestabilne zakresy występują w oto- czeniu prędkości kątowych, w których przecinają się mapy częstości własnych wyznaczonych oddzielnie dla drgań giętnych i drgań skrętnych. W artykule wykorzystano metodę linii pierwiastkowych, aby wykazać, które przecięcia są niestabilne i dlaczego.

Źródło:

Journal of Theoretical and Applied Mechanics; 2008, 46, 4; 829-844
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 44.

Tytuł:

Effect of Navel and Rotor Type on Physical and Mechanical Properties of Viscose Rotor Spun Yarns
Wpływ otworu wlotowego i typu wirnika na fizyczne własciwości wiskozowych przędz rotorowych

Autorzy:

Esfahani, R T
Shanbeh, M

Powiązania:

https://bibliotekanauki.pl/articles/232149.pdf

Data publikacji:

2014

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych

Tematy:

viscose yarns
rotor spinning
physical properties
navel type
rotor type
statistical evaluation
wiskoza
przędza rotorowa
właściwości fizyczne
typ wirnika
statystyczna ocena

Opis:

This work investigates the influence of the navel and rotor type on the tenacity (cN/tex), elongation at break (%), mass irregularity (CVm), total number of imperfections (IPI), hairiness (H-value), and twist difference values (ΔT%) of viscose rotor spun yarns. Twelve samples using six different navels and two kinds of rotor with a different structure of rotor grooves were produced. The nominal count was 20tex and the nominal twist value 800 twists per meter. Statistical assessment based on one-way analysis of variance (ANOVA) and the TukeyHSD test was performed at a 95% confidence level to study the effect of independent parameters and their interaction.
Badano wpływ otworu wlotowego i typu wirnika na wytrzymałość właściwą (cN/tex), wydłużenie przy zerwaniu (%), nieregularność masy (CVm), całkowitą liczbę błędów, włochatość i różnicę skrętów wiskozowych przędz rotorowych. Badano dwanaście próbek przy sześciu różnych otworach wlotowych i dwóch rodzajach wirnika posiadających różną konfigurację rowków. Stosowano przędzę o znamionowej masie liniowej 20 tex i znamionowym skręcie 800 skrętów na metr. Dokonano oceny statystycznej na podstawie jednoczynnikowej analizy wariancji (ANOVA) i testu Tukey’a przy 95% poziomie ufności.

Źródło:

Fibres & Textiles in Eastern Europe; 2014, 3 (105); 61-65
1230-3666
2300-7354

Pojawia się w:

Fibres & Textiles in Eastern Europe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 45.

Tytuł:

Wytwarzanie roztworów kazeinianu sodu mieszadłem typu stator-rotor w laboratoryjnym mieszalniku bez przegród
Production of sodium caseinate solution with the use of a stator-rotor stirrer in a laboratory mixer without partitions

Autorzy:

Wesołowski, P.
Gawałek, J.

Powiązania:

https://bibliotekanauki.pl/articles/288448.pdf

Data publikacji:

2013

Wydawca:

Polskie Towarzystwo Inżynierii Rolniczej

Tematy:

mieszadło stator-rotor
kazeinian sodu
pyliste ciało stałe
zawiesina lekkich cząstek
stator-rotor stirrer
sodium caseinate
powdery solid body
light particles suspension

Opis:

Na obecnym etapie prowadzonych od szeregu lat badań doświadczalnych, dotyczących wytwarzania wodnych roztworów pylistych ciał stałych, podjęto próbę sprawdzenia przydatności mieszalnika bez przegród z wysokoobrotowym mieszadłem typu stator-rotor do uzyskiwania wodnych roztworów kazeinianu sodu. Przeprowadzone badania modelowe wykazały wprawdzie możliwość znacznego skrócenia czasu mieszania w mieszalniku bez przegród z mieszadłem typu stator-rotor w stosunku do klasycznych mieszadeł mechanicznych, jednakże ze względu na bardzo silne napowietrzenie wytwarzanych koncentratów kazeinianu sodu nie zdecydowano się rekomendować takiego układu do zastosowania w praktyce przemysłowej.
At the present stage of research which have been carried out for many years concerning production of water solutions of powdery solid bodies, a test of checking suitability of a mixer without partitions with a high-rotation stator-rotor stirrer for obtaining water solutions of sodium caseinate was carried out. The model tests which were carried out proved a possibility of a considerable shortening of the mixing time in a mixer without partitions with the use of a stator-rotor mixer in comparison to classic mechanical stirrers. However, due to very high aeration of the produced concentrates of sodium caseinate, such a system is not recommended for use in industry.

Źródło:

Inżynieria Rolnicza; 2013, R. 17, nr 1, t. 1, 1, t. 1; 267-273
1429-7264

Pojawia się w:

Inżynieria Rolnicza

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 46.

Tytuł:

Model of the double-rotor induction motor in terms of electromagnetic differential

Autorzy:

Adamczyk, D.
Wilk, A.
Michna, M.

Powiązania:

https://bibliotekanauki.pl/articles/140805.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

double rotor
electromagnetic differential
induction machine

Opis:

The paper presents a concept, a construction, a circuit model and experimental results of the double-rotor induction motor. This type of a motor is to be implemented in the concept of the electromagnetic differential. At the same time it should fulfill the function of differential mechanism and the vehicle drive. One of the motor shafts is coupled to the direction changing mechanical transmission. The windings of the external rotor are powered by slip rings and brushes. The inner rotor has the squirrel-cage windings. The circuit model parameters were calculated based on the 7.5 kW real single-rotor induction motor (2p = 4). Experimental verification of the model was based on comparison between the mentioned single-rotor motor and double-rotor model with the outer rotor blocked. The presented results showed relatively good compliance between the model and real motor.

Źródło:

Archives of Electrical Engineering; 2016, 65, 4; 761-772
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 47.

Tytuł:

Interferencja wirnik nośny - wirnik ogonowy
Interference between the main and tail rotors

Autorzy:

Łusiak, T.

Powiązania:

https://bibliotekanauki.pl/articles/212441.pdf

Data publikacji:

2006

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

interferencja
wirnik nośny
wirnik ogonowy
interference
main rotor
tail rotor

Opis:

W artykule przedstawiono modele zaburzeń opływu śmigłowca w płaszczyźnie wirnika ogonowego wywołanych bliskością wirnika nośnego. Przedstawiono model śladu zawirnikowego w oparciu o zasadę Biota i Savarta w celu określenia zaburzeń pola prędkości indukowanej przez wirnik nośny w płaszczyźnie wirnika ogonowego [4].
The influence of disturbances to the flow around a helicopter resulting from a resultant reaction of the wake from the main rotor on the tail rotor, on the loading as well as control and noise of the helicopter was presented. The analysis was based on a rotational model of the system. The basis of the model of the interference is the replacement of wake generated by rotors and fixed lifting surfaces by a uniform rotational model in the form of discrete rotational grids. This allows for the integration of fields induced through all rotational elements of the system, in accordance with the Biot-Savart law. This law was accepted in view of the fact that, as the only law included in the flow model, it enables a constant processing of load calculations in an undefined flight, with the retention of a reasonable calculation time. The undertaking of this subject should help explain phenomena not completely recognized and which exert a significant influence on safety when operating helicopters certain states of flight. The results of modeling, carried out for the SW4 helicopter, contain an evaluation of disturbances of the field of flow around the tail rotor in given states of flight, in which the case of take-off in a sidewind and with the carrying out of a directional maneuver is of primary significance. In other cases, when the tail rotor does not enter into intensive disturbances of the velocity field by the main rotor, the interference phenomena are of lesser importance. The numerical program used allows for information about flow around and loads on the taił rotor in flow disturbed by the (main) rotor to be obtained. Resultant loads on the tail rotor can be evaluated, along with its chosen elements.

Źródło:

Prace Instytutu Lotnictwa; 2006, 1-2 (184-185); 198-202
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 48.

Tytuł:

Rationale for mu-synthesis control of flexible rotor-magnetic bearing systems

Autorzy:

Sawicki, J. T.

Powiązania:

https://bibliotekanauki.pl/articles/387247.pdf

Data publikacji:

2008

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

sterowanie odporne
niepewność pomiaru
robust control
flexible rotor
mu-synthesis
uncertainties

Opis:

The emergence of sophisticated formal control synthesis tools provokes important questions for any prospective user: why learn to use these new tools, what will they offer me? In synthesis of magnetic bearing controllers, it turns out that the range of stabilizing controllers is often quite narrow so that the difference between a poor controller and an “optimal” one may be small. Hence, the product of formal control synthesis tools often looks and performs much like what a reasonably clever control engineer would produce by hand. This paper demonstrates that the real value of these tools lies in a) generation of a performance benchmark which can be used to firmly establish the best performance relative to a specification and b) change of design parameter space to one which is relatively easy to maintain and represents a durable investment from an engineering process view.

Źródło:

Acta Mechanica et Automatica; 2008, 2, 2; 67-74
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 49.

Tytuł:

Problems of an aerodynamic interference between helicopter rotor slipstream and an elevated heliport

Autorzy:

Ruchała, Paweł
Grabowska, Kamila

Powiązania:

https://bibliotekanauki.pl/articles/244357.pdf

Data publikacji:

2019

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

transport
helicopter flight safety
rotor wake
elevated heliport

Opis:

An elevated heliport, as it has been defined by FAA (Federal Aviation Administration), is a heliport located on a rooftop or other elevated structure where the TLOF (touchdown and lift-off area) is at least 30 inches (76 cm) above the surrounding surface [1]. One of greatest advantages of such heliports is that they require less free space, which eases its build nearby existing buildings – especially in densely built-up areas. However, design of such heliports is more complicated, than ground level ones, while one must include an aerodynamic impact of the building below the elevated heliport and surrounding buildings. The aerodynamic interference between the helicopter and the buildings may result with decline of flight safety, due to sudden decrease of thrust (when flying above the edge of building) or because of increased turbulence in windy weather, wake behind surrounding buildings causing sudden gusts etc. Moreover, oscillations of pressure caused by helicopter rotor influence on the building structure also must be taken into account due to increased wear of upper part of the building or devices mounted on its roof (for example, elevator drives). These oscillation may also cause vibrations of building’s structure, which is especially important in case of medical heliports – which are a vast majority of elevated heliports (and heliports in general) – because of strict requirements for acceptable vibration level. The article is aimed on summarize aerodynamic issues, which should be taken into account during design of elevated heliport.

Źródło:

Journal of KONES; 2019, 26, 3; 189-196
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 50.

Tytuł:

Three-dimensional numerical analysis of internal flow phenomena in a diagonal rotor

Autorzy:

Bin, Y.
Keqi, W.

Powiązania:

https://bibliotekanauki.pl/articles/1955712.pdf

Data publikacji:

2004

Wydawca:

Politechnika Gdańska

Tematy:

diagonal rotor
numerical analysis
internal flow
tree-dimensional analysis

Opis:

A numerical analysis has been designed to study internal flow phenomena in a diagonal rotor. A calculated diagonal rotor was designed by a quasi-three-dimensional method. Its hub and casing walls were inclined 45o and 25o, respectively. The numerical simulation was based on the Navier-Stokes equations coupled with a k-ε turbulence model. We found that the rotor's wake was stronger near the hub and in the casing end wall region. The wake at a lower flow rate was stronger than that at a higher flow rate. Static pressure gradually increased from the hub to the casing along the height of a blade, on the rotor pressure surface and in the front 60% of the chord region of the suction surface. In the back 40% of the chord region of the suction surface, static pressure gradually decreased. A passage vortex formed in the stator flow passage and an 80% axial chord plane. It was located near the hub end-wall. The passage vortex developed into a large vortex centered near the midspan at a 99% axial chord plane of the stator. The casing wall boundary layer downstream of the rotor occupied approximately 10% of the flow passage. Along the height of a blade, the meridian velocity gradually increased upstream of rotor and decreased downstream. The calculated aerodynamic characteristic curve, the meridian velocity distribution upstream and downstream of the rotor, and the streamline distribution on the meridian surface were consistent with experimental results and design data. Our findings proved that the present numerical method is reliable and practicable. It can be used to design and analyze swept diagonal rotors in order to improve their surging and rotation stall state. The present results also provide comparative data for the design of highly-loaded swept diagonal rotors in future studies.

Źródło:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2004, 8, 1; 27-40
1428-6394

Pojawia się w:

TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 51.

Tytuł:

A novel rotor design for a hybrid excited synchronous machine

Autorzy:

Paplicki, P.

Powiązania:

https://bibliotekanauki.pl/articles/141651.pdf

Data publikacji:

2017

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

experimental result
field-weakening
finite element analysis
hybrid excitation
PM machine
rotor design

Opis:

The paper presents three novel rotor design concepts for a three-phase electric controlled permanent magnet synchronous machine (ECPMS-machine) with hybrid excitation. The influence of magnets and flux-barriers arrangement on the magnetic field distribution and field-weakening characteristics of the machine is examined, based on a three-dimensional finite element analysis (3D-FEA). Moreover, a prototype rotor design based on a new rotor concept with a good field-weakening capability is presented in detail. Finally, the experimental results of no-load back electromotive force (back-EMF) waveforms and field-weakening characteristics versus a control coil current of the machine are reported.

Źródło:

Archives of Electrical Engineering; 2017, 66, 1; 29-40
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 52.

Tytuł:

A comparison of helicopter main rotor features due to stiffness of rotor blade-hub connection
Porównanie własności wirnika nośnego śmigłowca przy różnej sztywności połączenia łopaty z głowicą wirnika

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/213599.pdf

Data publikacji:

2018

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

helicopter
main rotor
blade deformations
śmigłowiec
wirnik nośny
odkształcenia łopat

Opis:

The paper presents results of simulation calculations concerning an influence of stiffness of blade-hub connection on rotor loads and blades deflections in hover, level flight and pull up maneuver. The three versions of rotor are considered with articulated, elastic and stiff connections of blades and hub. The blades with the same distributions of stiffness, mass and the same aerodynamic characteristics are applied for all rotor cases. The rotor loads are calculated applying Runge-Kutta method to solve the equations of motion of deformable blades. According to the Galerkin method, the parameters of blades motion are treated as combination of considered blade bending and torsion eigen modes. The results of calculations indicate for possibility to generate the greater rotor control moments and to improve helicopter maneuverability in the case of applying the non-changed blade of articulated rotor combined with elastic rotor hub.
W pracy przedstawiono wyniki obliczeń symulacyjnych dotyczących wpływu sztywności połączenia łopat z głowicą na poziom obciążeń wirnika i odkształceń łopat w warunkach zawisu, lotu poziomego i wyrwania. Przyjęto trzy wersje wirnika nośnego z przegubowym, sprężystym i sztywnym połączeniem łopat i głowicy. Dla wszystkich przypadków wirnika przyjęto łopaty identycznym rozkładzie sztywności, mas i charakterystyk aerodynamicznych. Obciążenia wirnika nośnego wyznaczano rozwiązując metodą Runge-Kutta równania ruchu odkształcalnych łopat z uwzględnieniem metody Galerkina, gdzie parametry ruchu łopat traktowano jako złożenie giętnych i skrętnych postaci własnych łopat. Wyniki symulacyjne wskazują na możliwość generacji większych momentów sterujących wirnika i poprawę manewrowości śmigłowca w przypadku zabudowy niezmienianej łopaty wirnika przegubowego w zespole z głowicą sprężystą.

Źródło:

Prace Instytutu Lotnictwa; 2018, 1 (250); 114-131
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 53.

Tytuł:

Simulation investigation of operational conditions of rotor for high-speed compound helicopter

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/245640.pdf

Data publikacji:

2018

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

compound helicopter
rotor loads
blade deformation
helikopter
obciążenia wirnika
deformacja ostrza

Opis:

The article presents results of simulations concerning possibilities of rotorcraft performance enhancements for compound helicopters with introduced additional wings and propellers. The simple model of helicopter including a point mass of fuselage and a rotor treated as a disk was used for calculations of helicopter flight equilibrium conditions. For the defined flight states, the more detailed model of elastic blade was applied to compute magnitude of rotor loads and level of blade deformations. The model of elastic blade includes out-of-plane bending, in plane bending, and torsion effects due to variable aerodynamic and inertial loads of rotor blades. Equations of motion of rotor blades are solved applying Runge-Kutta method. Taking into account Galerkin method, parameters of blade motion are computed as a combination of assumed torsion and bending Eigen modes of the rotor blade. The six-bladed rotor with stiff connections of blades and hub was applied for comparison of flight envelope for conventional helicopter and versions of compound rotorcraft with additional propellers and with wings and propellers. Simulations indicate that, in the case of compound helicopter configuration, achieving the operational flight conditions at high speed of 400 km/h is possible without generating excessive loads and blade deformations. The results of calculations of rotor loads and generated blade deflections are presented in form of time-run plots and as rotor disk distributions, which depend on radial and azimuthal positions of blade elements. The simulation Keywords: compound helicopter, rotor loads, blade deformation 1.Introduction For classical configuration of helicopter, with main rotor and anti-torque tail rotor, the speed of flight is limited in comparison to fixed wing aircraft. The maximum speed of conventional helicopter is restricted due to high drag associated with compressibility effects for advancing rotor blade and stall phenomenon, which occurs at retreating blade zone. A compound helicopter configuration with added lifting wings and separate source of thrust for propulsion may help to unload main rotor and enhance speed range of rotorcraft. Initial development programs of compound helicopters [6], such as the Bell 533, the Lockheed XH-51A fitted with wings and additional turbojet engines, or the Lockheed AH-56A Cheyenne with wings and pushing propeller and after flight tests were not passed to serial production. Emerging demands for improved performance and progress in composite materials and aerodynamics of rotor blades gave impulse to return to compound helicopter concept. In the last decade, the new experimental compound helicopters with additional propulsion were tested [3]: the American Piasecki X-49 Speedhawk, the Sikorsky X2 and the French Eurocopter X3. It should be mentioned that the Eurocopter X3 achieved speed of 472 km/h setting an unofficial speed record for propeller helicopters. Analytical and experimental researchworks were performed to examine features of compound helicopters, which included effects of varying main rotor tip speed [1], wing-rotor lift share [7, 8] and investigation of dynamic stability characteristics [2]. Basing on collected experiences, the next generation of operational compound helicopter designs are being developed. The American Sikorsky S-97 Raider made the maiden flight in 2015 [4] and the European Airbus Helicopter Racer’s configuration was revealed in 2017 [5]. investigation may help to define demands for rotor of high-speed helicopter.

Źródło:

Journal of KONES; 2018, 25, 1; 363-370
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 54.

Tytuł:

Simulation investigation of rotor loads and blade deformations in steady states and at boundaries of helicopter flight envelope

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/246484.pdf

Data publikacji:

2017

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

helicopter
rotor loads
blade deformation

Opis:

Results of calculation of the helicopter main rotor loads and deformations of rotor blades are presented. The simulations concern level flight states and cases of boundary flight envelope such as wind gust, dive recovery and pull-up manoeuvre. The calculations were performed for data of the three-bladed articulated rotor of light helicopter. The method of analysis assumes modelling the rotor blades as elastic axes with sets of lumped masses of blade segments distributed along radius of blade. The model of deformable blade allows flap, lead-lag and pitch motion of blade including effects of out-of-plane bending, in-plane bending and torsion due to aerodynamic and inertial forces and moments acting on the blade. Equations of motion of rotor blades are solved applying Runge-Kutta method. Parameters of blade motion, according to Galerkin method, are considered as a combination of assumed torsion and bending eigen modes of the rotor blade. The rotor loads, in all considered cases of flight states, are calculated for quasi-steady conditions assuming the constant value of the following parameters: rotor rotational speed, position of the main rotor axis in air and position of swashplate due to rotor axis which defines the collective and cyclic control pitch angle of blades. The results of calculations of rotor loads and blade deflections are presented in form of timeruns and as distributions on rotor disk due to blade elements radial and azimuthal positions. The simulation investigation may help to collect data for prediction the fatigue strength of blade applying results for steady flight states and for definition the extreme loads for boundaries of helicopter flight envelope.

Źródło:

Journal of KONES; 2017, 24, 2; 239-246
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 55.

Tytuł:

Aeroelastic analysis of helicopter rotor using virtual blade model and equivalent beam model of a blade

Autorzy:

Sieradzki, A.

Powiązania:

https://bibliotekanauki.pl/articles/242703.pdf

Data publikacji:

2016

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotorcraft
helicopter
blade
aeroelasticity
rotor
aerodynamics
CFD
VBM

Opis:

Modern helicopter rotor blades design requires taking into account complex aeroelastic phenomena. Sophisticated computational fluid dynamics and structural dynamics models, available on the market, coupled together enable such analysis with very high fidelity. However, the computational cost of this type of simulation is usually very high and for this reason, it cannot be used in interactive design process or optimization run. Complex Fluid Structure Interaction models are excellent tools for validation purposes, but the design process requires simpler models with lower computational cost and still relatively high accuracy and capabilities. The paper presents a new efficient methodology for calculating helicopter rotor loads, deformations and performance. It uses the well-known Navier-Stokes equations aerodynamic solver – ANSYS Fluent, and modified Virtual Blade Model (based on Blade Element Theory) for rotor flow calculation. This connection guarantees exceptional capabilities and fidelity in comparison with simulation time. The dedicated structural dynamics solver, based on equivalent beam model of a blade and Finite Difference Method, was developed and coupled with CFD part using User Defined Functions in Fluent software. The accuracy of created module was validated with wind tunnel tests data of IS-2 helicopter rotor model, performed in Institute of Aviation. The results of calculations were compared with experimental data for a hover state and a forward flight with three different flight velocities. The comparisons showed very good agreement of the data in most of the analysed cases and pointed out new research possibilities. The presented aeroelastic helicopter rotor model combines all advantages of using three-dimensional Navier-Stokes solver with relatively low computational costs and high accuracy, confirmed by wind tunnel tests. It could be used successfully in helicopter rotor blades design process.

Źródło:

Journal of KONES; 2016, 23, 1; 297-304
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 56.

Tytuł:

Dynamic finite element analysis of rotor-shaft fastening into a heavy precise lathe

Autorzy:

Dounar, Stanislau
Jakubowski, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/1818744.pdf

Data publikacji:

2021

Wydawca:

Akademia Morska w Szczecinie. Wydawnictwo AMSz

Tematy:

finite element analysis (FEA)
lathe
rotor
renovation
rigidity
reinforcement

Opis:

The results of finite element analysis of large machined rotor fastened into heavy precise lathe are reported. Many design changes are simulated to improve the dynamic rigidity of the machining. Three radial eigenmodes detrimental to the accuracy were revealed: rotor-stock bending at 17.7 Hz (“half-wave”), rotor-lathe bending at 36.1 Hz (“full-wave”), and “support rocking” at 68.1 Hz. The frequency response functions and dynamic rigidities were evaluated. Three compliance issues were revealed: angular flexibility of the spindle console, low stiffness of the lathe bed (with boots), and an excessively slender tailstock. It is proposed to transform the spindle chuck into a table with additional hydrostatic backing, fill the bed cavities with concrete, and redesign the tailstock as a counter-spindle unit. This will decrease the amplitude of the main rotor resonance by 6.3 times and upshift the frequency near two-fold from 17.7 to 35 Hz. The renovated lathe should be able to machine a rotor without a lunette system or overriding the main resonant frequency.

Źródło:

Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2021, 66 (138); 37-45
1733-8670
2392-0378

Pojawia się w:

Zeszyty Naukowe Akademii Morskiej w Szczecinie

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 57.

Tytuł:

Computational investigation of vibration characteristics analysis for industrial rotor

Autorzy:

Aimeur, Noureddine
Menasri, Noureddine

Powiązania:

https://bibliotekanauki.pl/articles/2204679.pdf

Data publikacji:

2022

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

rotor dynamic
finite element method
reverse design
CMM
unbalanced
blade wear
simulation
ANSYS

Opis:

During the operation of a rotor, various types of vibrations appear in this mechanical system and often limit the performance and endanger the safety of the operation. Therefore, dynamic analysis is essential because precise knowledge of the vibration behaviour is essential to ensure proper operation. This article presents a set of scientific techniques for the modelling and simulation of rotor vibrations. To work out the equations of the vibratory movement of the rotor, we used the energy approach of Lagrange. To achieve this, a model with one blading wheel carried by a shaft supported by two hydrodynamic bearings is chosen basedon the characteristics of the rotor studied (Fan 280 cement draft fan). It is an arduous task to manually ascertain the analytical resolution of the differential equations that characterise the vibratory behaviour of the rotor. The numerical approach employing the finite element method, programmed on the ANSYS software, made it possible to perform the vibration analysis of the rotor. First, the FAN 280 cement draft fan rotor is modelled using SolidWorks 3D software and reverse design using the coordinate measuring machine (CMM) for the design of the fins. Then, the modal characteristics of the fan rotor model were analysed using the finite element analysis (FEA) software ANSYS Workbench. Also, to study the effect of blade wear on critical speeds, the Campbell diagram was obtained. Finally, harmonic analysis was performed to determine the amplitude of the rotor vortex at critical speeds obtained with and without blade wear.

Źródło:

Acta Mechanica et Automatica; 2022, 16, 4; 373--381
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 58.

Tytuł:

Modelowanie utraty stabilności układu wirnik-łożyska przy stochastycznej zmienności danych wejściowych
Modelling of stability loss of rotor-bearings system with stochastic variation of the input data

Autorzy:

Pietkiewicz, P.

Powiązania:

https://bibliotekanauki.pl/articles/209108.pdf

Data publikacji:

2008

Wydawca:

Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego

Tematy:

wirnik
niepewność danych
trajektoria
drgania
układ wirnik-łożyska
rotor
data uncertainty
vibrations
rotor-bearings system

Opis:

Artykuł zawiera wybrane wyniki obliczeń potwierdzających możliwość symulacji utraty stabilności przez układ wirnik-łożyska obciążonego siłą poprzeczną zmienną w czasie. Opracowane dotąd modele nie były wykorzystywane do tego typu prób. Przedstawione wyniki obliczeń dotyczą dwóch wariantów obciążenia wirnika.
The chosen calculation results, confirming the possibility of simulation of the stability loss by the rotor-bearings system, subjected to a time-warying shearing force are presented. Models formulated so far were not applied for such kind of tests. The presented results concern two variants of the rotor loading.

Źródło:

Biuletyn Wojskowej Akademii Technicznej; 2008, 57, 2; 15-22
1234-5865

Pojawia się w:

Biuletyn Wojskowej Akademii Technicznej

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 59.

Tytuł:

Synchronization and stability of an elastically coupled tri-rotor vibration system

Autorzy:

Hou, Y.
Du, M.
Fang, P.
Zhang, L.

Powiązania:

https://bibliotekanauki.pl/articles/279489.pdf

Data publikacji:

2017

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

tri-rotor
synchronization characteristics
stability
computer simulations

Opis:

A new mechanism, an elastically coupled tri-rotor system, is proposed to implement synchronization. It is composed of a rigid body, three induction motors, coupling unit and springs. According to the Lagrange equation, the model of the system is established. The average method of small parameters is applied to study the synchronization characteristics of the system, therefore, the balance equation and stability criterion of the system can be obtained. Obviously, many parameters affect the synchronous state of the rotors, especially the spring stiffness, the stiffness of the coupling unit and the installation location of the system. Finally, computer simulations are used to verify the correctness of theoretical analysis.

Źródło:

Journal of Theoretical and Applied Mechanics; 2017, 55, 1; 227-240
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 60.

Tytuł:

Computational investigations of active flow control on helicopter - rotor blades

Autorzy:

Stalewski, W.
Sznajder, K.

Powiązania:

https://bibliotekanauki.pl/articles/242558.pdf

Data publikacji:

2014

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

rotorcraft
rotor aerodynamics
active flow control
Active Gurney Flap
URANS
ANSYS Fluent

Opis:

The paper presents results of the first stage of the research conducted within the frames of Active Rotor Technologies, which is the dynamically developed sub-domain of Rotorcraft Engineering. The research concerned a computational modelling and investigations of new solutions aiming at improvement of performance of modern helicopters and their environmental impact, by active control of operation of their rotors. The paper focuses on one of such solutions applied for the active control of airflow around helicopter-rotor blades. This solution is the Active Gurney Flap – a small, flat tab located at a pressure side of rotor blade near its trailing edge, which is cyclically deployed and stowed during rotation cycles of the blade. The Active Gurney Flap seems to be very promising solution which will enable helicopters to operate with reduced power consumption or reduced main rotor tip speed whilst preserving current flight performance capabilities, especially in terms of retreating blade stall. The newly developed methodology of computational modelling of active-flow-control devices, like Active Gurney Flap, applied for enhance a helicopter performance and improve its environmental impact, has been presented. Development of the methodology was the challenging task, taking into account strongly unsteady character of modelled phenomena and large differences of scales in both the space and time domain, where very small, dynamically deflected tab strongly influences the flow around rotating, large main rotor. Exemplary CFD simulations, presented in the paper, have been conducted to validate developed methodology.

Źródło:

Journal of KONES; 2014, 21, 2; 281-288
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 61.

Tytuł:

Various Rotor Topologies of Line-Start Synchronous Motor for Efficiency Improvement

Autorzy:

Sarac, Vasilija Jovan
Stefanov, Goce

Powiązania:

https://bibliotekanauki.pl/articles/1193858.pdf

Data publikacji:

2020

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

line-start synchronous permanent magnet motor
rotor topology
transient characteristics
FEM

Opis:

Line-start synchronous permanent magnet motor (LSSPMM) is being considered as a replacement or alternative to asynchronous squirrel-cage motor (AM) in constant speed applications. This is due to the better efficiency and power factor than the asynchronous motor. There are various rotor topologies of LSSPMM concerning the magnets placement and their dimensions. The paper analyses six different rotor topologies in terms of achieving the best efficiency and power factor for the same output power of the motor with minimal consumption of permanent magnet material. All other motor design parameters remain unchanged, i.e. all motor topologies are analysed for the same stator laminations and the same motor windings. The numerical finite element method (FEM) models and dynamic models for obtaining transient characteristics of speed, torque and current verify the proposed design of various motor models. The results from all motor models are compared and adequate conclusions are derived regarding the optimal rotor topology in terms of obtaining the best efficiency and power factor with minimal consumption of permanent magnet material, for the same output power of the motor.

Źródło:

Power Electronics and Drives; 2020, 5, 40; 83-95
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 62.

Tytuł:

Nowoczesne wielopłatowe śmigło ogonowe do śmigłowca
Modern multiblade tail rotor

Autorzy:

Piłat, M. B.

Powiązania:

https://bibliotekanauki.pl/articles/213933.pdf

Data publikacji:

2008

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

lotnictwo
śmigłowce
wielopłatowe śmigło ogonowe
śmigłowiec IS-2
aviation
helicopters
modern multiblade tail rotor

Opis:

W artykule została przedstawiona koncepcja nowoczesnego śmigła ogonowego wielołopatowego do śmigłowca lekkiego IS-2. Proponowane rozwiązanie konstrukcyjne skupia w sobie najważniejsze cechy nowoczesnego smigła ogonowego zgodnego z powszechnie obowiązującymi tendencjami. Przedstawiono opis zaproponowanej konstrukcji wraz z ramowym zarysem technologicznym oraz wyniki wstępnych analiz obliczeniowych.
In this paper the concept of the modern multi blade tail rotor of IS-2 light helicopter is presented. The proposed design solution brings together the most important features of the modern tail rotor, which are conforming to common trends. A description of the proposed design, together with the manufacturing framework outline and results of a preliminary analysis is presented.

Źródło:

Prace Instytutu Lotnictwa; 2008, 3-4 (194-195); 280-296
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 63.

Tytuł:

Analiza powstawania leja w mieszalniku z układem typu rotor-stator użytym jako mieszadło
Analysis of a central vortex formation in a mixer with the rotor-stator system used as a stirrer

Autorzy:

Nykiel, S.
Wesołowski, P.
Alejski, K.

Powiązania:

https://bibliotekanauki.pl/articles/2072224.pdf

Data publikacji:

2013

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

mieszalnik
rotor-stator
powstawanie leja
mixer
vortex formation

Opis:

W pracy badano proces powstawania leja wokół wału wysokoobrotowego układu typu stator-rotor, pracującego jako mechaniczne mieszadło w osi zbiornika pozbawionego przegród. Analizowano wpływ częstości obrotów rotora oraz wysokości zawieszenia mieszadła nad dnem zbiornika na głębokość powstającego leja w trzech mieszalnikach o różnych stosunkach średnicy zbiornika do średnicy mieszadła D/d. Mieszanym medium była woda destylowana (t = 20°C), wypełniająca każdy z testowanych zbiorników do wysokości H - 2D. Stwierdzono, że względna głębokość leja wyraźnie wzrasta zarówno ze wzrostem częstości obrotów rotora jak i ze wzrostem względnej wysokości zawieszenia mieszadła nad dnem zbiornika.
Creation of a central vortex around the high speed shaft in rotor-stator type system, working as mechanical stirrer in the axis of tank without baffles was studied. Influence of rotor speed and the distance between agitator and tank bottom on the depth of a central vortex in three mixers with various geometric ratios Did (tank diameter to impeller diameter) was analyzed. Tested medium was distilled water (t - 20°C) filling each of the examined tanks to the level H = 2D. The relative depth of central vortex increased significantly with the increase of both the rotor speed and the relative distance between agitator and tank bottom.

Źródło:

Inżynieria i Aparatura Chemiczna; 2013, 5; 449--450
0368-0827

Pojawia się w:

Inżynieria i Aparatura Chemiczna

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 64.

Tytuł:

Zastosowanie algorytmu identyfikacji rezystancji wirnika do diagnostyki silnika indukcyjnego w czasie rzeczywistym
Application of rotor resistance identification algorithm for real-time diagnostics of induction motor

Autorzy:

Bednarz, Szymon
Dybkowski, Mateusz

Powiązania:

https://bibliotekanauki.pl/articles/304621.pdf

Data publikacji:

2019

Wydawca:

Wydawnictwo Druk-Art

Tematy:

silnik indukcyjny
uszkodzenie wirnika
identyfikacja rezystancji wirnika
MRAS
DFOC
induction motor
rotor fault
rotor resistance identification

Opis:

W artykule omówiono możliwość wykrywania uszkodzenia prętów klatki wirnika silnika indukcyjnego z zastosowaniem techniki opartej na identyfikacji parametrów schematu zastępczego maszyny. Metodyka ta bazuje na założeniu, że wybrane uszkodzenia mogą objawiać się zmianami parametrów silnika, a ich identyfikacja w czasie rzeczywistym i obserwowanie tych zmian pozwala na wczesną identyfikację uszkodzenia. W pracy wykorzystano fakt, że w przypadku pęknięcia prętów klatki wirnika symptomem uszkodzenia jest wzrost rezystancji schematu zastępczego wirnika. Do odtwarzania tego parametru zastosowano estymator adaptacyjny z modelem odniesienia (MRAS). Badania silnika indukcyjnego przeprowadzono w układzie bezpośredniego sterowania polowo zorientowanego (DFOC). W artykule przedstawiono wyniki badań symulacyjnych oraz eksperymentalnych.
This paper deals with the broken rotor bars detection in squirrel-cage induction motor using parameter identification approach. This method is based on the assumption, that the chosen failures may result in motor parameters variations. Real-time identification and observation of parameters variation allows to incipient fault detection. Increase of the rotor resistance value may be a good fault symptom, in the case of rotor bar damage. In the paper, the rotor resistance estimator based on the model reference adaptive system (MRAS) is utilized. The induction motor is operating in the direct field-oriented control structure, under different conditions. In the paper simulation and experimental results are shown.

Źródło:

Napędy i Sterowanie; 2019, 21, 5; 53-57
1507-7764

Pojawia się w:

Napędy i Sterowanie

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 65.

Tytuł:

Parametrical models of working rotor machine blade diagnostics with its unmeasurable environment elimination

Autorzy:

Lindstedt, P.
Grądzki, R.

Powiązania:

https://bibliotekanauki.pl/articles/386554.pdf

Data publikacji:

2010

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

łopatka wirnikowa
diagnostyka
model parametryczny
rotor blade
diagnostic
parametrical model

Opis:

The paper presents the basic of the new method of rotor machine blades during their operation. The method utilizes such diagnostic models as a quotient of diagnostic signal y(t) amplification being a result of blade operation and x(t) signal of its environment as the blade tip approaches the sensor as well as amplification of these signals as the blade tip recedes from the sensor and phase shift difference of these signals as the blade tip approaches and recedes from the sensor. The adopted diagnostic models indirectly take the current blade environment x(t) into account with no necessity of measuring (Kotowski and Lindstedt, 2007; Lindstedt and Kotowski, 2004). Therefore the model is sensitive to blade technical condition changes remaining only slightly sensitive to environment changes. Suggested method may prove very important in diagnostics of rotor blades during operation of rotor machines (turbines, compressors etc.).

Źródło:

Acta Mechanica et Automatica; 2010, 4, 4; 56-63
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 66.

Tytuł:

Initial Rotor Position Detection of Induction Machines Using Feedforward Sensorless Saliency Separation

Autorzy:

Montero, Eduardo Rodriguez
Vogelsberger, Markus
Wolbank, Thomas

Powiązania:

https://bibliotekanauki.pl/articles/1956005.pdf

Data publikacji:

2021

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

induction machine
harmonic compensation
rotor slotting saliency
sensorless control

Opis:

The use of induction machine spatial saliencies for sensorless vector control in the proximity of zero electrical frequency has been extensively researched over the last few decades. A robust technique to extract machine saliencies is called voltage step excitation, and it computes a saliency phasor out of phase current derivatives resulting from specific voltage steps generated by the inverter switching. Within the saliency phasor, all machine saliencies appear superposed. For some machine constructions, multiple saliencies are present, containing information about the spatial, magnetic and geometric state of the machine. Due to its direct relation with the rotor angle and its high accuracy, rotor slotting saliency is often chosen as the sensorless control signal. In order to exclusively access rotor slotting, saliency separation needs to be carried out, with the goal of eliminating all non-control saliencies from the saliency phasor. In this research, feedforward harmonic compensation based on look-up tables (LUTs) is chosen. The idea is to estimate each saliency in relation to amplitude and phase shift once, store such information in a torque-dependent LUT and use it for feedforward compensation. Yet, several saliencies are linked to the rotor position and, thus, the stored phase shift in the LUT is fixed to a defined rotor position at which the saliency estimation was performed. For the feedforward compensation to work during each sensorless start-up, an initial rotor slot detection must be carried out. This paper presents a technique to estimate initial rotor angle based only on the inherent characteristics of the induction machine multi-saliencies and an iterative feedforward compensation process that requires no extra resources and only a few PWM (Pulse Width Modulation) periods to achieve initial slot rotor angle. Experimental results measured at two different test benches prove the high accuracy of the method.

Źródło:

Power Electronics and Drives; 2021, 6, 41; 301-313
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 67.

Tytuł:

Optimization of a two-phase transverse flux switched reluctance motor with an outer rotor

Autorzy:

Łukaniszyn, M.
Kowol, M.
Kołodziej, J.

Powiązania:

https://bibliotekanauki.pl/articles/140820.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

transverse flux switched reluctance motor
outer rotor
optimization

Opis:

This paper presents optimization results for a two-phase, modular transverse flux switched reluctance motor (TFSRM) with an outer rotor. In particular, the main disadvantage of the considered motor structure, that is the zero starting torque in some rotor positions, is eliminated by construction optimization. A numerical model of the motor developed in the Flux3D program is coupled with a Matlab-based evolutionary algorithm for optimization of construction parameters of the magnetic circuit. The elaboratem algorithm is also connected with a database to limit the computation costs. Three objective functions are taken into account for the motor integral parameter improvement. The fundamental role of a type of an optimization criterion function is comparatively analyzed and a new effective criterion function is introduced.

Źródło:

Archives of Electrical Engineering; 2012, 61, 4; 567-578
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 68.

Tytuł:

Numerical simulation of feedback controlled fluid-induced instabilities in rotor system supported by hydrodynamic bearings

Autorzy:

Ferfecki, P.
Sikora, R.
Poruba, Z.

Powiązania:

https://bibliotekanauki.pl/articles/229847.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

rotor system
hydrodynamic bearing instability
kinematic excitation

Opis:

In certain operating conditions, the oil-film forces, by which the hydrodynamic bearings act on the rotor, destabilize and induce a self-excited vibration. There are many solution based on modifications of the bearing geometry to enlarge the operational range of the hydrodynamic bearing as a tilting pad bearing, lemon bore, etc. or usage of the dampers whose operation is based only on the dissipation of mechanical energy. In this paper several concepts based on controlled kinematic excitation of the bearing shells is investigated by computer simulation and by experimental test. The mathematical model of the uncontrolled and controlled rotor system contains the nonlinear hydrodynamic forces determined by the solution of the Reynolds equation assuming short case of bearing. To solve the equation of motion the Runge-Kutta method of the 4th order with Dormand-Prince modification and variable length of the integration step is used. The computer simulations were performed for rotor system without feedback control and with feedback controller. The main objectives of the numerical analysis were determination of the stability regions of the vibration excited by the imbalance forces. Results of the computer simulations proved that the analyzed approaches reduce amplitude of the rotor vibration caused by the imbalance forces. Experimental test and computer simulations demonstrate that the active vibration control increases considerably the rotation speed when the self-excited vibration of the oil-film occurred.

Źródło:

Archives of Control Sciences; 2010, 20, 3; 287-301
1230-2384

Pojawia się w:

Archives of Control Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 69.

Tytuł:

Effect of the sleeve profile on the stability of rotor operating in multilobe journal bearings

Autorzy:

Strzelecki, S.

Powiązania:

https://bibliotekanauki.pl/articles/127766.pdf

Data publikacji:

2016

Wydawca:

Politechnika Poznańska. Instytut Mechaniki Stosowanej

Tematy:

multilobe
offset journal bearings
stability of rotor
łożysko poprzeczne
stateczność wirnika

Opis:

Multilobe journal bearings with the sleeve of the 2-, 3 or 4- sliding lobes of cylindrical profile are applied in different types of rotating machinery. The design of such journal bearings, the number of lobes and oil grooves improves thermal state of bearing at higher speeds and the stability of operation. The paper describes the results of the calculations of dynamic characteristics and determination of stability ranges of simple symmetric rotor operating in the offset types of multilobe journal bearings. The dynamic characteristics of supporting bearings are defined by four stiffness and damping coefficients of oil film. The iterative solution of Reynolds, energy and viscosity equations allows the obtaining of the load capacity of bearings and the required dynamic coefficients of oil film. Adiabatic, laminar oil film and the static equilibrium position of journal were assumed. The oil film pressure, temperature, viscosity fields and the oil film forces were the basis of the bearing dynamic characteristics and stability determination.

Źródło:

Vibrations in Physical Systems; 2016, 27; 339-346
0860-6897

Pojawia się w:

Vibrations in Physical Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 70.

Tytuł:

Wind Tunnel Research on the Unmanned Aerial Vehicle Rotor Blade Setting Angle

Autorzy:

Siadkowska, Ksenia

Powiązania:

https://bibliotekanauki.pl/articles/101916.pdf

Data publikacji:

2020

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

wind tunnel
thermoanemometer
rotor blade
aerodynamic coefficient
UAV
tunel aerodynamiczny
łopata wirnika
współczynnik aerodynamiczny

Opis:

The recommended optimal twist angles were determined for particular sections of the prototype rotor blade dedicated to an unmanned helicopter. The main rotor blade was tested in the GUNT HM 170 tunnel for four different air flow velocities and variable angles of attack. The blade model was divided into sections, each of them was made in the 3D printing technology. For all the sections, the maximum lift and drag forces were determined and then converted to dimensionless values. The aerodynamic characteristics were calculated for each section and different air flow velocities in the wind tunnel. Due to the division of the blade into sections, it was possible to define the most favorable angles of attack along the rotor radius. Aerodynamic excellence was identified for each blade section and air flow velocities.

Źródło:

Advances in Science and Technology. Research Journal; 2020, 14, 4; 104-114
2299-8624

Pojawia się w:

Advances in Science and Technology. Research Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 71.

Tytuł:

Niestabilność huśtawkowego wirnika nośnego wiatrakowca działającego w opływie osiowym
Instability of the gyroplane teetering rotor in axial flow

Autorzy:

Cieślak, S.

Powiązania:

https://bibliotekanauki.pl/articles/212422.pdf

Data publikacji:

2014

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

wiatrakowiec
wirnik huśtawkowy
niestabilność
gyroplane
teetering rotor
instability

Opis:

W pracy przedstawiono wyniki obliczeń, mających na celu wstępną identyfikację zjawiska niestabilności łopat wirnika huśtawkowego pracującego w przepływie osiowym, np. w czasie prerotacji. Określono granicę wystąpienia niepożądanych zjawisk na łopatach w zależności od wielkości kąta skoku ogólnego i konstrukcyjnego kąta stożka. Analizom poddano model łopaty wirnika montowanego na budowanym w Instytucie Lotnictwa wiatrakowcu I-28 w wariancie B.
The paper presents the results of calculations aimed at a preliminary identification of the instability phenomenon of the teetering rotor blades operating in axial flow, for example, during the pre-rotation. The limit of adverse effects on the blades, depending on the size of the pitch angle and the design coning angle, was determined. Analyses were performed on a model of a rotor blade mounted in the gyroplane I-28 version B being built in the Institute of Aviation.

Źródło:

Prace Instytutu Lotnictwa; 2014, 2 (235) June 2014; 28-37
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 72.

Tytuł:

Active rotor vibration control
Aktywne sterowanie drganiami wirnika

Autorzy:

Viteckova, M.
Vitecek, A.
Tuma, J.

Powiązania:

https://bibliotekanauki.pl/articles/369032.pdf

Data publikacji:

2013

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

łożyska ślizgowe
aktywne sterowanie drganiami
drgania wirnika
active vibration control
rotor vibration
journal bearings

Opis:

The article deals with the analysis of active vibration control of a rotor which is supported by journal bearings. The oil fi lm between the journal and bushing induces the rotor instability, which causes rotor vibrations if rotational speed is greater than a threshold of system stability. This phenomenon is very important for high-speed rotational machines for which restricts the operational range of the rotational speed. Therefore increasing the rotor stability threshold is very important for preventing rotor vibrations. The rotor instability results in lateral vibrations which do not conform to the forces of the unbalanced masses or other external forces. The frequency of the lateral vibration is slightly less than half of the rotational frequency. The main result of the article is the analytical determination of the infl uence of the setting of the PD type controller on the threshold of stability.
Artykuł omawia analizę aktywnego sterowania drganiami wirnika podpartego łożyskami ślizgowymi. Film olejowy w szczelinie pomiędzy czopem i panwią łożyska wywołuje niestabilność wirnika, co dla prędkości obrotowej większej od progu stabilności systemu powoduje jego drgania. Zjawisko to jest bardzo ważne dla maszyn o wysokich prędkościach obrotowych, ponieważ ogranicza zakres prędkości roboczych. Dlatego podwyższenie progu stabilności wirnika jest bardzo znaczące dla zapobiegania drgań wirnika. Niestabilność wirnika przejawia się drganiami poprzecznymi, które nie są w zgodzie z siłami niewyważenia oraz pozostałymi siłami zewnętrznymi. Częstotliwość tych drgań poprzecznych jest nieco mniejsza niż połowa częstotliwości obrotowej wirnika. Podstawowym wkładem artykułu jest analityczne pokazanie wpływu regulatora PD na próg stabilności wirnika.

Źródło:

Mechanics and Control; 2013, 32, 2; 77-81
2083-6759
2300-7079

Pojawia się w:

Mechanics and Control

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 73.

Tytuł:

Determination of influence of internal surface roughness of a fan rotor onto its performance parameters

Autorzy:

Fortuna, S.

Powiązania:

https://bibliotekanauki.pl/articles/175530.pdf

Data publikacji:

2014

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

centrifugal fans
CFD simulation
fan performance prediction
surface roughness of rotor

Opis:

Computional fluid dynamics study and experimental test using the standard methods on flow characteristics of the centrifugal fan, have been presented in this paper. This investigation was performed to determine the influence of internal surface roughness of fan rotor onto its performance parameters. The testing results are presented in form of graphs showing the efficiency, pressure and power in function of flow.

Źródło:

Transactions of the Institute of Fluid-Flow Machinery; 2014, 126; 111-121
0079-3205

Pojawia się w:

Transactions of the Institute of Fluid-Flow Machinery

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 74.

Tytuł:

Analiza sterowania wirnikiem śmigłowca bezpilotowego
Analysis the control of the rotor of the unmanned helicopter

Autorzy:

Parafiniak, M.

Powiązania:

https://bibliotekanauki.pl/articles/213225.pdf

Data publikacji:

2010

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

awionika
sterowanie wirnikiem śmigłowca
śmigłowiec bezpilotowy
avionics
rotor of the unmanned helicopter

Opis:

Praca poświęcona jest zagadnieniom związanym ze sterowaniem wirnika śmigłowca bezzałogowego, którego układ konstrukcyjny – w tym układ sterowania - jest zbliżony do konstrukcji śmigłowców załogowych. Analizie poddano pojedynczy tor sterowania wykorzystujący jako element wykonawczy siłownik hydrauliczny pracujący w pętli sprzężenia zwrotnego. Zasadnicza cześć pracy opisuje zastosowanie programów wspomagających projektowanie do modelowania i symulacji przebiegu procesu sterowania, wykorzystanych podczas opracowania stanowiska do prób toru sterowania wirnikiem i badania siłownika elektrohydraulicznego. Wykorzystując środowisko Matlab/Simulink zbudowano model cyfrowy stanowiska oraz przeprowadzono symulacje pozwalające ocenić prawidłowość założeń konstrukcyjnych oraz ocenę jakości sterowania jak też właściwości dynamicznych i statycznych siłownika jako elementu układu wykonawczego. Zrealizowane prace potwierdziły, że zastosowanie serwomechanizmów elektro-hydraulicznych może zapewnić prawidłowość sterowania wirnikiem śmigłowca. Po zastąpieniu pilota przez układ pilotażowo-nawigacyjny, który realizowałby kompletne sterowanie obiektem, z tym zestawem siłowników: do obsługi wirnika, śmigła ogonowego i silnika, możliwe staje się sterowanie bezzałogowymi aparatami latającymi.
The goal of this report is related with the control of the rotor of the unmanned helicopter, whose construction design – including the control system – is similar to the construction design of manned helicopters. The object of analysis is a single control circuit, consisting of a hydraulic cylinder actuator operating in a feedback loop. The main part of the report describes the use of CAD programs for modelling purposes and the simulation of the control process. The same CAD programs were used during the design of the rotor control test station and the electro-hydraulic actuator control analysis. Matlba/Simulink was used to construct a digital model of the test station, as well as used to perform simulations allowing allowing to asses the accuracy of the quality of the construction, as well as the quality of the steering, as well as the dynamic and static properties of the actuator as a part of the executive system. The finalized work has confirmed that the use of electro-hydraulic servo-mechanisms can assure a correct control of the rotor. After replacing the pilot with a pilot-navigation system, which would have a complete control of the object, and with the addition of of the electro-hydraulic actuators used to control the rotor, tail propeller and engine, the control of the unmanned helicopter through these apparatuses becomes possible.

Źródło:

Prace Instytutu Lotnictwa; 2010, 4 (206); 112-118
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 75.

Tytuł:

Analiza niezawodności wirnika wentylatora lutniowego
Reliability Analysis of Ventube Fan Rotor

Autorzy:

Wrzesień, S.
Jasztal, M.

Powiązania:

https://bibliotekanauki.pl/articles/403646.pdf

Data publikacji:

2015

Wydawca:

Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego

Tematy:

mechanika
niezawodność
wytrzymałość
współczynnik bezpieczeństwa
wirnik wentylatora
mechanics
reliability
strength
safety factor
fan rotor

Opis:

Obiektem badań w niniejszej pracy były tarcze wirnika wentylatora lutniowego. W pierwszym etapie pracy wykonano obliczenia analityczne, w wyniku których wyznaczone zostały rozkłady naprężeń promieniowych, obwodowych oraz wartości współczynnika bezpieczeństwa wzdłuż promienia tarczy. W drugim etapie pracy opisano związek istniejący pomiędzy funkcją niezawodności elementu konstrukcji a współczynnikiem bezpieczeństwa wyrażonym w sposób probabilistyczny. Przedstawiona postać funkcji niezawodności pozwoliła wyznaczyć wpływ wartości rozproszenia zmiennych losowych obciążenia i wytrzymałości wokół ich wartości oczekiwanych na wartość niezawodności wybranego elementu konstrukcji. W pracy porównano deterministyczną wartość współczynnika bezpieczeństwa z jego wielkością wyznaczoną w ujęciu probabilistycznym dla różnych parametrów rozkładów prawdopodobieństwa wytrzymałości i naprężeń występujących w elemencie.
Discs of ventube fan rotor were chosen as an object of the study. As a result of an analytical calculation, distribution of radial and circumferential stress and safety factor along rotor’s disc radius was calculated. Present paper displays relation between reliability function of structure element and safety factor through introducing probabilistic description of its value. Presented form of the reliability function gave the possibility of influence’s estimation of stress and strength’s variate dispersion round the expected value on reliability of structure element. Authors weighed deterministic value of safety factor against its value calculated in probabilistic way for various stress and strength distribution parameters.

Źródło:

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa; 2015, 6, 2 (20); 41-53
2081-5891

Pojawia się w:

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 76.

Tytuł:

Effects of imperfect grooves in full-floating ring bearings on dynamics of a turbocharger rotor

Autorzy:

Smolík, Luboš
Polach, Pavel
Hajžman, Michal

Powiązania:

https://bibliotekanauki.pl/articles/2146577.pdf

Data publikacji:

2020

Wydawca:

Politechnika Poznańska. Instytut Mechaniki Stosowanej

Tematy:

rotor
dynamics
uncertainty
bearings
wirnik
dynamika
niepewność
łożyska

Opis:

Full-floating ring bearings cause nonlinear vibrations of turbocharger rotors, and they have higher hydrodynamic power losses in comparison with rolling element bearings. Both issues can be improved if several shallow axial grooves are machined in the inner surface of the floating ring. The grooves are usually not manufactured precisely in order to keep production costs as low as possible. This work investigates the role of the machining errors on the dynamics of the turbocharger rotor. More specifically, the effects of the precisely-machined grooves on the dynamics of the system are explained. Then the influence of the uncertainties on both vibrations and hydrodynamic power losses in the bearings is investigated.

Źródło:

Vibrations in Physical Systems; 2020, 31, 2; art. no. 2020226
0860-6897

Pojawia się w:

Vibrations in Physical Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 77.

Tytuł:

Badanie mikromieszania płynów w mieszalniku typu rotor-stator z wykorzystaniem złożonych reakcji testowych
Application of complex test reactions to micromixing investigation in a rotor-stator mixer

Autorzy:

Jasińska, M.
Bałdyga, J.
Cooke, M.
Kowalski, A.

Powiązania:

https://bibliotekanauki.pl/articles/2070941.pdf

Data publikacji:

2010

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

mieszanie
reakcje złożone
rotor-stator
selektywność
diazowanie
mixing
complex reactions
selectivity
diazocoupling

Opis:

Celem pracy jest identyfikacja stanu wymieszania na skalę molekularną w mieszalniku typu rotor-stator z zastosowaniem złożonych reakcji testowych. Parametrem informującym bezpośrednio o stanie wymieszania była w tym przypadku selektywność reakcji diazowania. W pracy podjęto próbę interpretacji wyników doświadczalnych z zastosowaniem modeli mieszania połączonych z obliczeniową mechaniką płynów (CFD). Wyniki pokazują, że zastosowany układ reakcji może być z powodzeniem wykorzystany do opisu mieszania na skalę molekularną w mieszalnikach typu rotor-stator.
The aim of this work was the identification of micromixing in a rotor-stator mixer using complex chemical reactions. The parameter informing about a state of micromixing was the selectivity of diazo-coupling. In this work an interpretation of experimental results is been presented. For this purpose the mixing model in combination with the computational fluid dynamics was applied. Results show that the proposed set of reactions can be efficiently used to describe mixing on molecular scale in the rotor-stator mixer.

Źródło:

Inżynieria i Aparatura Chemiczna; 2010, 2; 59-60
0368-0827

Pojawia się w:

Inżynieria i Aparatura Chemiczna

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 78.

Tytuł:

Unscented Kalman filters and wavelet analysis of asynchronous machine with rotor eccentricity and broken rotor bars
Bezśladowe Filtry Kalmana oraz analiza falkowa maszyny asynchronicznej z ekscentrycznością wirnika i pękniętymi prętami wirnika

Autorzy:

Mazur, D.

Powiązania:

https://bibliotekanauki.pl/articles/155996.pdf

Data publikacji:

2011

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

filtry Kalmana
ekscentryczność wirnika
silnik indukcyjny
prądy skrośne
Kalman filters
rotor eccentricity
induction motors
cross currents

Opis:

A multislice, 2.5 dimensional model was used to calculate the state variables waveforms of an asynchronous machine. In this model a magnetic field is calculated in orthogonal to the machine axis, two-dimensional intersections with use of the finite element method. The wavelet transform was used to visualize the waveform harmonic components. The performed analysis showed that the wavelet transform can be successfully used in the analysis of the asynchronous machine waveforms, as an alternative to the short time Fourier transform. The calculations were performed in the Academy Computational Center in Cracow, Poland.
Do obliczenia przebiegów zmiennych stanu maszyny asynchronicznej zastosowano model "multislice 2.5D". Model ten oblicza pole magnetyczne w przekrojach prostopadłych do osi maszyny wykorzystując metodę elementów skończonych. Dla celów analizy quasistacjonarnych przebiegów w maszynie przedstawiono alternatywną do metody krótkoczasowego przekształcenia Fouriera (STFT) metodę falek (wavelet). Obliczenia wykonane zostały w Akademickim Centrum Obliczeniowym w Krakowie. W celu określenia ilości pękniętych prętów oraz odcinków pierścieni klatki wirnika silnika asynchronicznego zastosowano filtr UKF. Dawał on dokładne informacje, podając numery uszkodzonych prętów oraz odcinków pierścieni. Dla uzyskania tak dokładnych informacji filtr ten wymagał pomiarów prądów stojana oraz prądów dodatkowych, jednozwojowych cewek umieszczonych na zębach stojana, a obciążonych dużymi rezystancjami (~1 k?). Potrzebny też był pomiar prędkości obrotowej wirnika i związany z tym kąt obrotu wału maszyny. Opracowana metoda nadaje się do ochrony dużych, kosztownych napędów asynchronicznych.

Źródło:

Pomiary Automatyka Kontrola; 2011, R. 57, nr 12, 12; 1579-1582
0032-4140

Pojawia się w:

Pomiary Automatyka Kontrola

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 79.

Tytuł:

Simulation investigation of aerodynamic effectiveness reduction of helicopter tail rotor
Symulacyjne badanie zmniejszenia aerodynamicznej efektywności śmigła ogonowego śmigłowca

Autorzy:

Stanisławski, J.

Powiązania:

https://bibliotekanauki.pl/articles/213785.pdf

Data publikacji:

2016

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

helicopter
tail rotor
aerodynamic effectiveness
śmigłowiec
śmigło ogonowe
efektywność aerodynamiczna

Opis:

Paper presents the results of the simulation tests concerning the performance of the tail rotor in the directional maneuver of the helicopter due to the flow changes of the tail rotor blades. The calculation model includes the yawing of the helicopter fuselage and motion of the tail rotor blades treated as the set of the deformable elastic axes with distributed lumped mass. The equations of motion of the tail rotor blades are solved by applying Runge-Kutta method taking into account the bending and torsion eigen modes of the blades. The results of the calculations indicate occurrence of the significant changes of the tail rotor thrust during directional maneuver of the helicopter in case of side wind or influence of the main rotor vortices.
Przedstawiono wyniki obliczeń symulacyjnych dotyczących pracy śmigła ogonowego w manewrze kierunkowym śmigłowca z uwzględnieniem zmiennych warunków opływu łopat śmigła. W modelu obliczeniowym uwzględniono ruch obrotowy sztywnego kadłuba oraz parametry pracy odkształcalnych łopat śmigła ogonowego traktowanych jako osie sprężyste z przypisanym rozkładem mas skupionych. Równania ruchu łopat rozwiązywano metodą Runge-Kutta z uwzględnieniem giętnych i skrętnych postaci własnych łopat. Wykonane obliczenia wskazują na możliwość wystąpienia znacznych zmian ciągu rozwijanego przez śmigło ogonowe w szczególnych przypadkach realizacji manewru kierunkowego przy podmuchach bocznych lub przy oddziaływaniu zaburzeń opływu pochodzących od wirnika nośnego.

Źródło:

Prace Instytutu Lotnictwa; 2016, 1 (242); 36-56
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 80.

Tytuł:

The influence of the blades leading edge anti-erosion protection on main rotor performances

Autorzy:

Wojtas, M.
Czajkowski, Ł.
Sobieszek, A.

Powiązania:

https://bibliotekanauki.pl/articles/243585.pdf

Data publikacji:

2018

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

airfoil
rotor blades
flight tests
light rotorcrafts
ultra-light rotorcrafts

Opis:

This article presents the influence of rotor blade airfoil shape on main rotor performances. In this case, we analysed the influence of anti-erosion tape, which is applied to the leading edge of the blade to protect the blades from environmental conditions. In Gyro-Tech Innovation an Aviation Company and Institute of Aviation the independent tests of helicopter and gyroplane main rotors were performed. Research includes: bench tests, on the test stand for dynamic testing of insulated rotors and tests on two flying constructions, gyroplane Cavalon produced by AutoGyro GmbH Company and ultralight helicopter Dynali H3. On the test bench, a two-blade rotor, used in ultralight and unmanned helicopters, was tested. In article, the authors present importance of the proper selection and application of anti-erosion coatings on rotor blades. Discuss the behaviour of the above-mentioned constructions with main rotor blades leading edge covered anti-erosion tape, during flight tests. The results of bench tests, including the comparison of polar curves of the main rotor with anti-erosion coating and without were also presented and discussed. In the summary of this article among others the solution of technological pocked introduced in the rotor blade, corresponding to the thickness of the anti-erosion tapes, in such way that after tape is applied it does not change the contour of the blade airfoil were presented.

Źródło:

Journal of KONES; 2018, 25, 2; 409-414
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 81.

Tytuł:

Damage evolution of vehicle motor rotor under single working condition based on GTN model

Autorzy:

He, Liange
Yuan, Zhou
Shi, Wenjun
Qu, Xiang

Powiązania:

https://bibliotekanauki.pl/articles/2200831.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

motor rotor
GTN model
parameters fitting
void evolution

Opis:

To study evolution of the void in the material of a motor rotor under different working conditions from a mesoscopic perspective, damage analysis of the rotor has been carried out based on thermal-mechanical coupling theory. According to the test methods of GB/T 228.1-2010 Part 1 and GB/T 228.2-2015 Part 2, tensile tests were conducted on rotor ma- terials at different temperatures to obtain basic mechanical property parameters, and pa- rameters of the fine-scale damage model at different temperatures were fitted by combining orthogonal tests and a finite element inverse calibration method. Then, the accurate tem- perature distribution law of the motor rotor was obtained through CFD calculation. Based on the material parameters and temperature data, the void evolution of the rotor material under thermal-mechanical load was studied by using the finite element method. The results show that: under the rated conditions, the stress concentration of the rotor is mainly ap- peared in the joint with the shaft, the maximum stress was 304.1MPa, which did not reach the yield limit of the material. No plastic deformation occurred, so the volume fraction of voids inside the rotor material did not change still for the initial pore volume fraction of 2.5 · 10−3. In the peak condition, the stress concentration appeared in the rotor plate across the joint of the magnetic bridge and pole shoe with a maximum stress of 354.4MPa and a small plastic strain of 1.133 ·10−3. The pore volume fraction increased to 2.503 ·10−3, where the initial pore growth of 2.150 · 10−6 and the secondary pore nucleation of 2.079 · 10−12.

Źródło:

Journal of Theoretical and Applied Mechanics; 2022, 60, 4; 561--577
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 82.

Tytuł:

Rotor fault detector of the converter-fed induction motor based on RBF neural network

Autorzy:

Kowalski, C. T.
Kaminski, M.

Powiązania:

https://bibliotekanauki.pl/articles/200439.pdf

Data publikacji:

2014

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

induction motor
rotor fault
diagnostic symptom
RBF neural network
fault detector

Opis:

This paper deals with the application of the Radial Basis Function (RBF) networks for the induction motor fault detection. The rotor faults are analysed and fault symptoms are described. Next the main stages of the design methodology of the RBF-based neural detectors are described. These networks are trained and tested using measurement data of the stator current (MCSA). The efficiency of developed RBF-NN detectors is evaluated. Furthermore, influence of neural networks complexity and parameters of the RBF activation function on the quality of data classification is shown. The presented neural detectors are tested with measurement data obtained in the laboratory setup containing the converter-fed induction motor (IM) and changeable rotors with a different degree of damages.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 1; 69-76
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 83.

Tytuł:

Strength analysis of a prototype composite helicopter rotor blade spar

Autorzy:

Kliza, Rafał
Ścisłowski, Karol
Siadkowska, Ksenia
Padyjasek, Jacek
Wendeker, Mirosław

Powiązania:

https://bibliotekanauki.pl/articles/2097429.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Promocji Wiedzy

Tematy:

FEM
composite spar
main rotor blade
carbon fiber
strength analysis

Opis:

This paper investigates the strenght of a conceptual main rotor blade dedicated to an unmanned helicopter. The blade is made of smart materials in order to optimize the efficiency of the aircraft by increasing its aerodynamic performance. This purpose was achieved by performing a series of strength calculations for the blade of a prototype main rotor used in an unmanned helicopter. The calculations were done with the Finite Element Method (FEM) and software like CAE (Computer-Aided Engineering) which uses advanced techniques of computer modeling of load in composite structures. Our analysis included CAD (Computer-Aided Design) modeling the rotor blade, importing the solid model into the CAE software, defining the simulation boundary conditions and performing strength calculations of the blade spar for selected materials used in aviation, i.e. fiberglass and carbon fiber laminate. This paper presents the results and analysis of the numerical calculations.

Źródło:

Applied Computer Science; 2022, 18, 1; 5--19
1895-3735

Pojawia się w:

Applied Computer Science

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 84.

Tytuł:

Symptomy diagnostyczne defektów konstrukcji podpierającej wirnik
The diagnostic symptoms of defects in the rotor supporting structure

Autorzy:

Żywica, G.

Powiązania:

https://bibliotekanauki.pl/articles/328308.pdf

Data publikacji:

2008

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

maszyna wirnikowa
wirnik
dynamika
analiza defektów
rotating machine
rotor dynamics
defects analysis

Opis:

Prezentowany artykuł dotyczy analizy defektów konstrukcji podpierającej wirnik. Obiektem badań było wielkogabarytowe Stanowisko Badawcze Dynamiki Wirników i Łożysk. Podczas badań wykorzystany został zweryfikowany, numeryczny model badanej maszyny wirnikowej. Analizie poddano kilka wybranych klas defektów, które mogłyby się pojawić podczas normalnej eksploatacji maszyny. W ramach badań przeprowadzono obszerne obliczenia symulacyjne, które pozwoliły na sformułowanie wniosków na temat wpływu poszczególnych defektów na warunki pracy maszyny wirnikowej. Udowodniono również, że niektóre z analizowanych defektów mogą mieć istotny wpływ na drgania wirnika.
In the presented article the author's attention was focused most of all on analysis of supporting structure defects. The object of investigation was the large-dimension Rotor Dynamics and Bearing Research Rig. During the examination the verified numerical model of the rotating machine was used. A few classes of defects, which could appear in operation process, were considered. In scope of investigation the extensive numerical calculation were performed. It allowed to assess the influence of some defects on dynamic characteristics of the rotor machine. It has been proven in the article that some defects of supporting structure might have significant influence on the rotor vibrations.

Źródło:

Diagnostyka; 2008, 1(45); 115-120
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 85.

Tytuł:

Rotor Resistance Estimator based on Virtual Current Sensor Algorithm for Induction Motor Drives

Autorzy:

Adamczyk, Michał

Powiązania:

https://bibliotekanauki.pl/articles/1193854.pdf

Data publikacji:

2020

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

induction motor drive
rotor resistance estimator
model reference adaptive system
virtual current sensor
fault tolerant control

Opis:

In this article, model reference adaptive system (MRAS)-based estimator of a rotor resistance of an induction motor (IM) is presented. In contrast to the solutions known from the literature, the reference model of this estimator uses the measured values of the phase current and the adaptive part is a virtual current sensor. The article presents an accurate description of the algorithm taking into account the discrete equations for possible practical implementation in the microprocessor system. In the first step, the impact of motor parameters to stator current estimation quality in the adaptive model was checked. Subsequently, simulation tests of the proposed rotor resistance estimator were carried out for the field-oriented control of the induction motor drive system with a model of an induction motor with fixed parameters and an induction motor with a changing main inductance according to a magnetisation curve. The analysis of the estimator’s work showed its high efficiency and insensitivity to changes in the IM main inductance.

Źródło:

Power Electronics and Drives; 2020, 5, 40; 143-156
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 86.

Tytuł:

Main inductances of induction motor for diagnostically specialized mathematical models

Autorzy:

Węgiel, T.
Weinreb, K.
Sułowicz, M.

Powiązania:

https://bibliotekanauki.pl/articles/141392.pdf

Data publikacji:

2010

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

silnik indukcyjny
uszkodzenie wirnika
diagnostyka
ekscentryczność wirnika
wirnik
induction motors
rotor fault diagnosis
rotor eccentricity

Opis:

In the paper modeling of main inductances for mathematical models of induction motors is applied to study the effects caused by a rotor eccentricity and saturation effects. All three possible types of eccentricity: static, dynamic and mixed are modeled. The most important parameters describing rotor eccentricity include self and mutual inductances of the windings. The structural changes of the permeance function as a result of eccentricity appearance and the Fourier spectra of inductances in occurrence of saturation for each case are determined in the paper. The presented algorithm can be used for the diagnostically specialized models of induction motors.

Źródło:

Archives of Electrical Engineering; 2010, 59, 1-2; 51-66
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 87.

Tytuł:

Study of a new type of Flettner rotor in merchant ships

Autorzy:

Li, Boyang
Zhang, Rui
Li, Yajing
Zhang, Baoshou
Guo, Chao

Powiązania:

https://bibliotekanauki.pl/articles/1573694.pdf

Data publikacji:

2021

Wydawca:

Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa

Tematy:

ship propulsion
flettner rotor
wind energy
rotating cylinder
numerical simulation

Opis:

Wind energy is a clean and renewable source of energy. This study seeks to explore the potential for utilising wind power for merchant ships. A new type of Flettner rotor (rotating cylinder) mounted on the superstructure of a ship is proposed and numerically simulated. The construction and installation of the rotating cylinder is designed and a numerical simulation of the ship-mounted cylinder is carried out, using the commercially available CFD code Ansys Fluent to obtain parameters such as lift and drag coefficient of the cylinder in different conditions. Specifically, it is found that the cylinder type superstructure can play a certain role in reducing the effect of friction by comparing traditional and cylindrical superstructures; the rotating cylinder can generate auxiliary thrust for the ship. After analysis, the wind speed around the cylinder and spin ratio will have a direct influence on its thrust effect; there is an inflection point in the lift coefficient with the increase of α; the thrust coefficient (8.63) reaches the maximum environmental wind speed at 10 m/s and spin ratio is 2.5. For the rotating cylinder, the greater the environmental wind, the greater the thrust contribution generated under the same spin ratio conditions. The maximum thrust can reach 750,000 N; the cylinder’s auxiliary propulsion contribution shows a better advantage in α = 2.0. The effective power generated by the cylinder reaches a maximum of 2,240 kW for environmental wind speed = 20 m/s and α = 1.0.

Źródło:

Polish Maritime Research; 2021, 1; 28-41
1233-2585

Pojawia się w:

Polish Maritime Research

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 88.

Tytuł:

Wpływ geometrii profilu lotniczego łopaty wirnika głównego na osiągi wiatrakowca
The influence of the main rotor blade aerofoil geometry on the gyroplane performance

Autorzy:

Pietrosiński, M.

Powiązania:

https://bibliotekanauki.pl/articles/213623.pdf

Data publikacji:

2015

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

wiatrakowiec
rejestrator
wirnik
gyroplane
registrar
rotor

Opis:

Celem pracy jest ocena wpływu geometrii profilu na osiągi wiatrakowca. Pomiaru dokonano podczas prób wlocie wirników z łopatami o profilu N9H12i ILU. W pracy przedstawiono odczyty z aparatury pomiarowo-rej es trującej zamontowanej na wiatrakowcu Zen-1, miejsca i metodą montażu czujników. Wyniki zestawiono tak, aby porównać osiągi wiatrakowca podczas lotu z łopatami o danych profilach. Wykazano poprawę osiągów na wiatrakowcu z łopatami o profilu ILU.
The aim of the study was to evaluate the effect of profile geometry on the performance of the gyroplane. The measurements were performed during flight testing rotors with blades profile N9H12 and JL11. The paper presents the results from registrar which was mounted on the gyroplane Zen-1. Article shows place and method to installed sensors of registrar. The results are summarized so, compare the performance of the gyroplane during the flight with blades of data profiles. It has been shown to improve performance on the gyroplane with blades profile JL11.

Źródło:

Prace Instytutu Lotnictwa; 2015, 4 (241); 62-72
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 89.

Tytuł:

Research of work of a rotor crush machine on elastic foundation with the use of graphs

Autorzy:

Zinko, R.

Powiązania:

https://bibliotekanauki.pl/articles/127726.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Instytut Mechaniki Stosowanej

Tematy:

mathematical model
rotor crush machine
elastic foundation
model matematyczny
rozdrabniacz wirnikowy
podłoże sprężyste

Opis:

The use of graphs for the research of a rotor crush machine work on elastic foundation is offered. For machines the structure graph of its design is being written. The graph of levels structure of the generalized coordinates of mathematical model is being formed on the basis of structure graph of machine design. It allows building of the mathematical model, which describe the physical processes of the machine work quickly and qualitatively.

Źródło:

Vibrations in Physical Systems; 2014, 26; 343-350
0860-6897

Pojawia się w:

Vibrations in Physical Systems

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 90.

Tytuł:

Uproszczona piasta dla śmigłowca o masie startowej 7000 kg
Simplified tail rotor hub for helicopter with 7000kg take-off mass

Autorzy:

Raczyński, R.

Powiązania:

https://bibliotekanauki.pl/articles/213931.pdf

Data publikacji:

2008

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Lotnictwa

Tematy:

lotnictwo
śmigłowce
uproszczona piasta
aviation
helicopters
simplified tail rotor

Opis:

W artykule przedstawiono koncepcje rozwiazania bezłożyskowego śmigła ogonowego śmigłowca wielozadanioliego klasy PZL Sokół. Podano analizy obliczeniowe torsjonu kompoztytowego metodą MES.
This article presents the design concept of bearingless tail rotor propeller hub for multitask class helicopter PZL Sokół. An computational analysis for composite torsion bar performed with FEM method is given.

Źródło:

Prace Instytutu Lotnictwa; 2008, 3-4 (194-195); 287-294
0509-6669
2300-5408

Pojawia się w:

Prace Instytutu Lotnictwa

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 91.

Tytuł:

Rotor optimization of axial-radial flux type synchronous machine based on magnetic flux leakage

Autorzy:

Qiu, Hongbo
Zhang, Shubo

Powiązania:

https://bibliotekanauki.pl/articles/1841116.pdf

Data publikacji:

2021

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

ARFTPMSM
rotor structure
three-dimensional model
magnetic leakage
konstrukcja wirnika
model trójwymiarowy
wyciek magnetyczny

Opis:

The axial-radial flux type permanent magnet synchronous machine (ARFTPMSM) can adjust the main magnetic field by controlling the axial flux, so it can overcome the problem that the flux of the permanent magnet synchronous motor (PMSM) is difficult to adjust. Due to the existence of the axial device in the ARFTPMSM, the finite element method (FEM) is used to establish a three-dimensional model for analysis. By analyzing the magnetic density distribution of the rotor, it is found that there is a serious magnetic leakage phenomenon at both ends of the tangential permanent magnet. The rotor material at the end of the tangent permanent magnet is replaced by non-ferromagnetic material to reduce the magnetic leakage. On this basis, the influence of the width of the non-ferromagnetic material on the performance of the motor is compared. By Fourier decomposition of the back-EMF waveform, the total harmonic distortion (THD) rate of the back-EMF under different axial magnetomotive force (MMF) was calculated. Finally, the eddy current distribution and the eddy current loss of the rotor are analyzed, and the variation law of the eddy current loss is summarized. The conclusion can provide reference for the optimal design of the ARFTPMSM.

Źródło:

Archives of Electrical Engineering; 2021, 70, 3; 551-566
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 92.

Tytuł:

Determination of parameters for a design of the stable electro-dynamic passive magnetic support of a high-speed flexible rotor

Autorzy:

Szolc, T.
Falkowski, F.
Henzel, M.
Kurnyta-Mazurek, P.

Powiązania:

https://bibliotekanauki.pl/articles/201250.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

rotor dynamics
electrodynamic passive magnetic bearings
active magnetic damper
stability analysis
rotor- shaft system
dynamika rotora
wirnik
amortyzator magnetyczny
analiza stabilności
pasywne łożysko magnetyczne

Opis:

Electro-dynamic passive magnetic bearings are now viewed as a feasible option when looking for support for high-speed rotors. Nevertheless, because of the skew-symmetrical visco-elastic properties of such bearings, they are prone to operational instability. In order to avoid this, the paper proposes the addition of external damping into the newly designed vibrating laboratory rotor-shaft system. This may be achieved by means of using simple passive dampers that would be found among the components of the electro-dynamic bearing housings along with magnetic dampers, which satisfy the operational principles of active magnetic bearings. Theoretical investigations are going to be conducted by means of a structural computer model of the rotor-shaft under construction, which will take into consideration its actual dimensions and material properties. The additional damping magnitudes required to stabilize the most sensitive lateral eigenmodes of the object under consideration have been determined by means of the Routh-Hurwitz stability criterion.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 1; 91-105
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 93.

Tytuł:

Application of Neural Networks and Axial Flux for the Detection of Stator and Rotor Faults of an Induction Motor

Autorzy:

Ewert, Paweł

Powiązania:

https://bibliotekanauki.pl/articles/1193708.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

induction motor
stator faults
rotor faults
diagnostics
axial flux
neural network

Opis:

The paper presents the possibility of using neural networks in the detection of stator and rotor electrical faults of induction motors. Fault detection and identification are based on the analysis of symptoms obtained from the fast Fourier transform of the voltage induced by an axial flux in a measurement coil. Neural network teaching and testing were performed in a MATLAB–Simulink environment. The effectiveness of various neural network structures to detect damage, its type (rotor or stator damage) and damage levels (number of rotor bars cracked or stator winding shorted circuits) is presented.

Źródło:

Power Electronics and Drives; 2019, 4, 39; 201-213
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 94.

Tytuł:

Stability analysis and dynamic behaviour of a flexible asymmetric rotor supported by active magnetic bearings

Autorzy:

Attia Hili, M.
Bouaziz, S.
Haddar, M.

Powiązania:

https://bibliotekanauki.pl/articles/280401.pdf

Data publikacji:

2017

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

asymmetric rotor
finite element
Floquet’s theory
dynamic coefficients
stability

Opis:

The objective of this work is to show the influence of dynamic characteristics of Active Magnetic Bearings (AMBs) on the stability and dynamic response of an asymmetric and unbalanced rotor. Indeed, AMBs have been successfully applied in several industrial machinery facilities. Their main advantages are the contactless working principle, frictionless suspension and operation in very high speeds. Firstly, the AMBs dynamic support parameters have been obtained through electromagnetic theory. Then, a generalized system equations of motion have been derived using the finite element method. The motion of a rotor the shaft cross-section of which is asymmetric is generally governed by ordinary differential equations with periodic coefficients. Floquet’s theory is used to investigate the stability of this system of equations. Finally, numerical simulation results are presented and discussed.

Źródło:

Journal of Theoretical and Applied Mechanics; 2017, 55, 3; 751-763
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 95.

Tytuł:

An application of order tracking procedure for diagnosis technical state of rotor system in shut - down process

Autorzy:

Grządziela, A.
Kluczyk, M.

Powiązania:

https://bibliotekanauki.pl/articles/242634.pdf

Data publikacji:

2013

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

dynamics
vibration
gas turbines
rotor vibration
shut-down process
order analysis

Opis:

Vibration diagnostic tests of marine gas turbine engines are performed as a research of on-line and off-line types. On-line systems generally monitored one or two vibration symptoms, which asses the limited and/or the critical values of parameters and they, potentially, can warn and/or shutdown engines. Off-line Systems are usually used for vibration analysis during non-steady state of work. The paper presents a new method of vibration diagnostics of rotor bearing system of gas turbine systems. The study assumes implementation of characteristics of vibration signals during the shut-down process of the rotor. The shut-down process is non-stationary so the studies used the order tracking procedure. Identified orders constitute individual characteristics as a function of changes of the rotational speed and shut-down process time. These allow the observation of changes in the support rigidity of the rotor in the frequency domain and change the bearing resistance torque as a function of changing time of the shut-down process. The resulting characteristics are as reference fingerprints for each of the rotors. Changes in the characteristics of the primary evidence of the processes of wear. Changes in the stiffness of rotor supports make change the amplitude of orders and frequency of the resonance signals observed in the frequency domain - decreasing rotational speed. The bearing wear results in changes in the shut-down time between successive intervals of characteristic rotational speed and the total shut-down time.

Źródło:

Journal of KONES; 2013, 20, 1; 111-118
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 96.

Tytuł:

Influence of cooling air mass flux variation on the convective heat transfer coefficient of HPT rotor disk

Autorzy:

Domański, R.
Jedliński, K.

Powiązania:

https://bibliotekanauki.pl/articles/243193.pdf

Data publikacji:

2007

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

CFD
Fluent
High Pressure Turbine
Rotor Disk
convective heat transfer coefficient

Opis:

The paper is focused on the convective heat transfer phenomena on the High Pressure Turbine (HPT) rotor disk wall. The disk is a part of PW6000 turbojet engine (designed by Pratt & Whitney Company) and is a base of the 1st stage of HPT blades having very high temperature (combustion gases leaving combustion chamber have temperature around 1800 K). The analyzed disk is cooled by the air taken from one of the compressor's stages. The air gets to the gap between HPT disk and mini disk through discrete pump holes and then divides into two streams. One of them is used to decrease temperature of turbine blades and the second one is directed to the sequent turbine stages. Numerical analysis (made in Fluent) is based on the two dimensional aerodynamic model (in steady state) which is the cross section of the real geometry. There are three different sets of boundary conditions analyzed. Each of them has the same flow splits (40% of air is used to cool turbine blades and 60% gets to the next turbine stage) and all settings except cooling air mass flow on the inlet. Convective heat transfer coefficients are calculated using different method then proposed by Fluent (WFHTC and SHTC options give wrong results in this case). Coefficients are presented along disk wall and are compared with Fluent calculation methods.

Źródło:

Journal of KONES; 2007, 14, 2; 107-114
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 97.

Tytuł:

Rotor blade vibration simulator of steam turbine with aliasing frequencies up to 25 Hz

Autorzy:

Piechowski, L.
Rządkowski, R.
Troka, P.
Piechowski, P.
Szczepanik, R.

Powiązania:

https://bibliotekanauki.pl/articles/175409.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

tip-timing
rotor blade vibration
blade vibration simulator

Opis:

The tip-timing measurement of rotor blade vibration of a real turbine is very expensive. An electronic simulator of unshrouded steam turbine rotor blade vibrations for aliasing frequencies up to 25 Hz is presented in this paper. The results of the simulated blade vibrations were compared with ones carried out on a real steam turbine. The simulator can be also used to: calibrate the measurement channels, help in the designing and manufacturing new tip-timing systems, and check the reliability of other tip-timing systems.

Źródło:

Transactions of the Institute of Fluid-Flow Machinery; 2016, 134; 121-129
0079-3205

Pojawia się w:

Transactions of the Institute of Fluid-Flow Machinery

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 98.

Tytuł:

Identyfikacja modelu konstrukcji podpierającej maszyny wirnikowej
Identification of model support structure of rotor machine

Autorzy:

Żywica, G.
Rybczyński, J.

Powiązania:

https://bibliotekanauki.pl/articles/327866.pdf

Data publikacji:

2006

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

dynamika maszyn
maszyna wirnikowa
identyfikacja
symulacja komputerowa
machine dynamics
rotor machine
identification
computer simulation

Opis:

W pracy omówiono proces identyfikacji modelu konstrukcji podpierającej wirnik na przykładzie wybranej maszyny wirnikowej. Obiektem badań była konstrukcja podpierająca wirnik wielkogabarytowego Stanowiska Badawczego Dynamiki Wirników i Łożysk, znajdującego się w Laboratorium Wibrodiagnostyki Instytutu Maszyn Przepływowych PAN w Gdańsku. W kolejnych punktach omówiono wszystkie etapy procesu identyfikacji, tzn.: eksperyment, modelowanie, estymację parametrów oraz weryfikację modelu. W wyniku identyfikacji otrzymano model dobrze odzwierciedlający zachowanie rzeczywistego obiektu oraz umożliwiający jego dalszą, wszechstronną analizę.
The paper discusses an identification process of the rotor support structure model in relation to selected example of rotor machine. The object of investigation was the rotor support structure of the large-size Dynamics of Rotors and Bearings Test Rig, located in Vibro-diagnostics Laboratory of Institute of Fluid Flow Machinery PAS, Gdansk. All stages of identification process have been talked over: experiment, modeling, estimation of parameters and model verification. As the result of identification, the structure model has been built, which well reflects the actual object and enables its subsequent diverse analysis.

Źródło:

Diagnostyka; 2006, 4(40); 71-76
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 99.

Tytuł:

Rezystancja przejscia pakiet-pręt w wirnikach z klatką miedzianą odlewaną

Autorzy:

Dąbała, K.

Powiązania:

https://bibliotekanauki.pl/articles/320354.pdf

Data publikacji:

2006

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

silniki indukcyjne klatkowe
straty w wirniku
rezystancja przejścia pakiet-pręt
squirrel-cage induction motors
rotor losses
transverse rotor-bar-iron resistance

Opis:

W artykule przedstawiono krótki przegląd metod wyznaczania rezystancji przejścia pakiet-pręt w wirnikach silników klatkowych, sposób przeprowadzenia badań wirników z klatką miedzianą odlewaną i dla porównany wirników z klatką aluminiową odlewaną, wyniki tych badań i wnioski.
Short review of resistance rotor-bar-iron determination methods, the way of copper rotor measurements execution and for comparison of aluminum rotors, the results of these tests and conclusion are presented in this paper.

Źródło:

Elektrotechnika i Elektronika; 2006, 25, 2; 133-137
1640-7202

Pojawia się w:

Elektrotechnika i Elektronika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 100.

Tytuł:

Studies on the influence of rotor unit unbalance on the operational parameters of a turbocharger of the NAPIER C-045 type

Autorzy:

Adamkiewicz, A.
Kuropatnicki, M.

Powiązania:

https://bibliotekanauki.pl/articles/360167.pdf

Data publikacji:

2013

Wydawca:

Akademia Morska w Szczecinie. Wydawnictwo AMSz

Tematy:

turbocharger
rotor unit
unbalance
operational parameters
technical conditions

Opis:

This paper presents the results of studies on the influence of unbalance of the rotor unit of a turbocharger on its operational parameters. Identification of the study object, a turbocharger of the NAPIER C-045 type, has been performed. The experiment was carried out at a test stand identifying turbocharger operational parameters belonging to the rotor unit unbalance group. Basing on the measured values and using a mathematical model, hypothetical values of operational parameters for different loads of Diesel engines were calculated. The obtained experimental results were compared to the calculated ones. On this basis, the studied turbochargers were classified into one out of three categories describing operational utility class of a given turbocharger. The order of sensitivity of turbocharger operational parameters to the unbalance of the rotor unit was established.

Źródło:

Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2013, 34 (106); 12-18
1733-8670
2392-0378

Pojawia się w:

Zeszyty Naukowe Akademii Morskiej w Szczecinie

Dostawca treści:

Biblioteka Nauki

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