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Wyszukujesz frazę "hydraulic losses" wg kryterium: Temat


Tytuł:
Parametry technologiczne procesu filtracji pospiesznej wód podziemnych przez złoża oksydacyjne i chemicznie nieaktywne
Technological parameters of groundwater rapid filtration through oxidative and non-active filtration materials
Autorzy:
Jeż-Walkowiak, J.
Dymaczewski, Z.
Sozański, M. M.
Powiązania:
https://bibliotekanauki.pl/articles/399974.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
filtracja
straty hydrauliczne
wody podziemne
filtering
hydraulic losses
groundwater
Opis:
Badania prowadzono na instalacji doświadczalnej składającej się z trzech kolumn filtracyjnych. Wyniki badań pozwoliły porównać straty hydrauliczne osiągane w czasie filtracji przez złoża chemicznie aktywne i czyste złoża kwarcowe.
In the paper the results of laboratory and pilot research on filtration process are presented. The oxidative and chemically non-active filtration materials were used. The experimental installation was implemented. The results of the research allowed to estimate and compare the values of hydraulic head loss for tested filtration materials.
Źródło:
Inżynieria Ekologiczna; 2011, 26; 112-121
2081-139X
2392-0629
Pojawia się w:
Inżynieria Ekologiczna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydraulic gradient prediction for solid-water mixture flow through horizontal pipelines of different diameters and roughness and solids concentrations
Autorzy:
Osra, Faisal A.
Powiązania:
https://bibliotekanauki.pl/articles/1844347.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
deposit limit velocity
hydraulic gradient
hydraulic losses
slurry flow
solid concentrations
suspended solids
wastewater
Opis:
In wastewater treatment plants, large pumps are often used to accommodate unknown hydraulic properties of solid-water mixture flow. The use of large pumps translates into higher purchasing and operating costs. Wastewater mixture is pumped with solids of different types and concentrations through pipelines. The design of these ducts is mainly based on the hydraulic laws of solid-water mixture which is represented by a corrected friction coefficient corresponding to the concentration of solids in water. This paper experimentally studies hydraulic properties of solid-water mixtures in pipelines by the varying Froude number (Fr), which represents the velocity mixture, solid concentration, pipeline diameter and pipeline material type-roughness coefficient. The experiments have been conducted in the wastewater treatment plant where six solid concentrations can be found ranging from 2 to 12% by weight. The pipe diameter ranges between 100 to 300 mm. It has been found that both the friction coefficient and the hydraulic gradient ameliorate with the increase of the pipeline roughness and the solids concentration in the water mixture, whereas the Fr drop with the diameter of the pipeline. The results are translated into curves and equations to predict the corrected pipeline friction coefficient and the hydraulic gradient of the solid-water mixture flow through horizontal pipelines at various solids concentrations, roughness and diameters.
Źródło:
Journal of Water and Land Development; 2021, 49; 267-272
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation and experimental research of hydraulic losses of an energy converting flow machine with rotating piston
Autorzy:
Nozdrzykowski, K.
Komorowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/135380.pdf
Data publikacji:
2017
Wydawca:
Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:
energy-converting machine
rotating pistons
imulation of hydraulic losses volumetric efficiency
comparative analysis
correlation and integral calculi
Opis:
This article describes the construction and principles of operation of a prototype energy-converting machine – a flow machine with pistons rotating in toroidal spaces. A comparative analysis of the results of simulation and experimental tests of fluid flow resistance in the presented prototype machine has been performed with the use of correlation and integral calculi. The article also presents a comparative analysis of the volumetric efficiency of the examined pump and of a Vogelsang pump with similar design and size. The present state of the research makes it possible draw conclusions about the high exploitation value of the proposed pump construction. For this displacement pump, performance increases along with rotational speed. However, it is different from other pumps by virtue of is simple and compact construction as well as greater capacity in relation to its size.
Źródło:
Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2017, 49 (121); 54-58
1733-8670
2392-0378
Pojawia się w:
Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Studies of Hydraulic Losses and Carbon Dioxide Concentration in The Space Under The Face Mask Protecting Against Covid-19
Autorzy:
Teleszewski, Tomasz Janusz
Gładyszewska-Fiedoruk, Katarzyna
Sulewska, Maria Jolanta
Powiązania:
https://bibliotekanauki.pl/articles/27314856.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
face masks
COVID-19
hydraulic losses
mask material
carbon dioxide concentration
maski na twarz
straty hydrauliczne
materiał maski
stężenie dwutlenku węgla
Opis:
Masks are the primary tool used to prevent the spread of COVID-19 in the current pandemic. Tests were carried out to determine the total pressure drop through the materials from which the masks are made and the correlation of these results with the concentration of carbon dioxide in the inner space of the mask. The results showed that a parameter representing hydraulic losses of the mask material has a significant influence on the concentration of carbon dioxide in the inner space of the mask. Masks with higher hydraulic resistances accumulated a higher concentration of carbon dioxide, and generated greater fluctuations of carbon dioxide as a function of time, which may be caused by compensation of the respiratory system. For example, in a two-layer mask (mask no. 3) the hydraulic resistance values are about three times higher than in a single-layer mask (mask no. 1). The study also noticed that the inscriptions and prints placed on the masks increase the hydraulic resistance of the material from which the masks are made, which may also contribute to the accumulation of carbon dioxide in the space between the mask and the face. To reduce the accumulation of carbon dioxide within the inner space of the mask, the results of this work suggest searching for mask materials with the lowest possible hydraulic resistance.
Źródło:
Civil and Environmental Engineering Reports; 2022, 32, 4; 13--24
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the powers of energy losses in a variable capacity displacement pump determined without or with taking into account the power of hydraulic oil compression
Autorzy:
Paszota, Z.
Powiązania:
https://bibliotekanauki.pl/articles/260427.pdf
Data publikacji:
2015
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
hydrostatic drive
variable capacity displacement pump
volumetric losses of hydraulic oil compression
Opis:
Powers of energy losses in a variable capacity displacement pump are compared with or without taking into account the power of hydraulic oil compression. Evaluation of power of liquid compression in the pump was made possible by the use of method, proposed by the Author, of determining the degree of liquid aeration in the pump . In the method of determining the liquid aeration in the pump and of powers of volumetric losses of liquid compression a simplified formula (qPvc . ΔpPi)/2 was used describing the field of indicated work of volumetric losses qPvc of liquid compression during one shaft revolution at indicated increase ΔpPi of pressure in the chambers. Three methods were used for comparing the sum of powers of volumetric losses ΔPPvl due to leakage and ΔPPvc of compression and also of mechanical losses resulting from increase ΔpPi of indicated pressure in the working chambers.
Źródło:
Polish Maritime Research; 2015, 2; 32-43
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of selected parameters on pressure distribution in the face throttle of a centrifugal pump automatic balancing device
Wpływ wybranych parametrów na rozkład ciśnienia w szczelinie poprzecznej tarczy odciążającej pompy odśrodkowej
Autorzy:
Tarasevych, Yuliia
Sovenko, Nataliia
Powiązania:
https://bibliotekanauki.pl/articles/2055621.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
non-contact seal
pressure distribution
hydraulic local losses
automatic balancing device
random parameters
uszczelnienie bezkontaktowe
rozkład ciśnienia
pompa wirowa
zmiany losowe
Opis:
Face throttles are a necessary functional element of non-contact face seals and automatic balancing devices of centrifugal pumps of different constructions. To calculate the hydrodynamic forces and moments acting on the rotor and fluid flow through the automatic balancing device, it is necessary to know the pressure distribution in the cylindrical and face throttle when considering all important factors which predetermine fluid flow. The face throttle surfaces are moving, which leads to unsteady fluid flow. The movement of the walls of the face throttle causes an additional circumferential and radial flow, which subsequently leads to the additional hydrodynamic pressure components. The paper analyses viscous incompressible fluid flow in the face throttle of an automatic balancing device taking into account the axial and angular displacements of throttle’s surfaces and the inertia component of the fluid. The effect of local hydraulic losses as well as random changes in the coefficients of local hydraulic resistance at the inlet and outlet of the throttle is analysed.
Szczeliny poprzeczne są niezbędnym elementem funkcjonalnym bezstykowych uszczelnień czołowych oraz tarcz odciążających pomp odśrodkowych o różnej konstrukcji. Konieczna jest znajomość rozkładu ciśnienia w szczelinie poprzecznej z uwzględnieniem wszystkich najważniejszych czynników determinujących przepływ cieczy w celu obliczenia sił hydrodynamicznych oraz natężenia przepływu. Powierzchnie szczeliny są ruchome, co powoduje niestacjonarny przepływ płynu. Ruch ścianek szczeliny powoduje dodatkowy przepływ obwodowy oraz promieniowy, a to w konsekwencji prowadzi do powstania dodatkowego ciśnienia hydrodynamicznego. W pracy wykonano analizę przepływu lepkiego nieściśliwego płynu przez szczelinę poprzeczną tarczy odciążającej pompy odśrodkowej z uwzględnieniem przemieszczeń osiowych i kątowych powierzchni szczeliny. Uwzględniono składowe bezwładności płynu. Przeanalizowano wpływ strat lokalnych oraz losowych zmian współczynników hydraulicznych strat miejscowych na wlocie i wylocie szczeliny poprzecznej na rozkład ciśnienia.
Źródło:
Tribologia; 2021, 297, 3; 35--44
0208-7774
Pojawia się w:
Tribologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Verification the mathematical model of energy efficiency of hydraulic system
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/245887.pdf
Data publikacji:
2017
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
hydraulic systems
hydraulic transmission
energy efficiency
constant capacity pump
energy losses
mathematical model
Opis:
The article presents the laboratory verification of the mathematical description of losses and energy efficiency of the hydraulic transmission with proportionally controlled cylinder supplied by the constant capacity pump in the system of constant pressure is presented. The axial piston pump with pivoting rotor supplied to the system consisted of proportional directional control valve and linear motor – hydraulic cylinder at constant pressure, cooperating with an overflow valve. The choice of the analysed system is not accidental. There is always a view in literature about the very limited energy capabilities of a proportional control system. For this purpose, measurement methods were developed and a test stand was adapted. It consists of two systems: tested and loading. Measurements during the tests were recorded up to date on the computer hard disk. In order to allow for comparison of the total efficiency of the system with the efficiency derived from the simulation, the ki coefficients determining the energy losses of the individual components were calculated. Investigations have shown a high convergence mathematical description of energy losses in the elements of the system efficiency and reality. This allows accurate simulation determining the energy efficiency of the field at every point in its operation, i.e. at any speed and any load-controlled hydraulic cylinder. The speed and load range of the hydraulic cylinder can also be accurately simulated.
Źródło:
Journal of KONES; 2017, 24, 3; 275-281
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation method and mathematical model of pressure losses in hydraulic rotary motor
Autorzy:
Maczyszyn, A.
Powiązania:
https://bibliotekanauki.pl/articles/259344.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
hydrostatic drive
power values of energy losses
hydraulic rotary motor
pressure losses
pressure efficiency
Opis:
This paper presents a way of determining the coefficient k8 of the pressure losses ΔpMp (flow drag) in internal ducts of SWSB-63 hydraulic motor. The coefficient is determined at a flow rate equal to the theoretical capacity QPt of the pump feeding the motor , the losses are related to the nominal pressure pn in the hydraulic system. The investigations followed a model of energy performance of hydraulic rotary motor, proposed by Z. Paszota.
Źródło:
Polish Maritime Research; 2018, 1; 93-98
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristics of loss power in compared hydraulic systems
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/241595.pdf
Data publikacji:
2017
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
power
energy losses
hydraulic system
pump
throttling valve
cylinder
Opis:
In this article, two hydrostatic systems with a throttling steering fed by a constant capacity pump were compared. It also includes a subject matter connected with an energy loss power of hydrostatic systems with hydraulic cylinder controlled by proportional directional control valve. Diagrams of loss power of two hydraulic systems worked at the same parameters of a speed and a load of hydraulic cylinder, which were different due to structure and ability of an energy saving, were presented and were compared. There are possibilities to reduce energy losses in proportional control systems (in the pump, in the throttle control unit, especially in the cylinder), and thus to improve the energy efficiency of the throttling manifold. The considerations allow for comparison of the loss power resulting from the applied hydraulic control structure of the hydraulic cylinder and the power consumed by the pump from the electric motor that drives it, the power necessary to provide the required unchanged usable pump-driven hydraulic cylinder. Presents the impact on the output (useful) power of the power consumed in the considered systems, and the impact on the power consumed of the loss power in the individual elements. Instantaneous useful power of the cylinder, which is determined by the product of force and speed of the cylinder rod, is independent of all losses. There are mechanical loss power occurs in the cylinder, the loss power in the conduits, the structural volume and pressure loss power that are associated with the throttling control and loss power in the pump: pressure, volumetric and mechanical which have to be added to the useful power. As a result, the sum of the effective useful power and the loss power of all system is the instantaneous value of the power consumed by the pump from the electric motor that drives it.
Źródło:
Journal of KONES; 2017, 24, 2; 217-223
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Method of sum of power losses as a way for determining the ki coefficients of energy losses in hydraulic motor
Autorzy:
Maczyszyn, A.
Powiązania:
https://bibliotekanauki.pl/articles/259421.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
hydrostatic drive
power of energy losses
hydraulic rotary motor
Opis:
This paper shows application of the method of sum of power losses to determining energy losses which occur in hydraulic rotary motor in situation when not all laboratory data are at one’s disposal or when no use is made of data contained in catalogue charts. The method makes it possible to determine the coefficients, ki, of energy losses occurring in the motor. The method of sum of power losses is based on the approach proposed by Z. Paszota, in the papers [3 ÷ 9]. It consists in adding power flow of energy losses occurring in the motor to power flow output and comparing the sum to the power flow input. Application of the method is exemplified by using a A6VM hydraulic motor.
Źródło:
Polish Maritime Research; 2016, 2; 57-67
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Graphical interpretation of the power of energy losses and power developed in the hydrostatic drive and control system elements
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/259894.pdf
Data publikacji:
2012
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
hydraulic motor
energy balance
energy losses
energy efficiency
capacity pump
hydraulic servomechanism
hydrostatic drive system
Źródło:
Polish Maritime Research; 2012, 4; 44-53
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Friction losses in a linear hydraulic motor as a result of the influence of the control structure and oil viscosity
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/241950.pdf
Data publikacji:
2018
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
friction force
mechanical losses
energy efficiency
oil viscosity
hydrostatic drive
hydraulic cylinder
Opis:
The problem of energy tests of hydraulic systems with hydraulic cylinders, seemingly simple displacement machines, is more complex than that of rotary hydraulic systems. The results of the researches provide an insight into the impact of external loads, required speed, structure of the power supply system, viscosity of hydraulic oil on friction loss, and the efficiency of cylinder drive. The hydraulic cylinder is the strongest structure in the system. Failure of the system is most likely due to failure of the pump supplying the cylinder. The high load of the pump is often caused by the very low energy efficiency of the cylinder, which, despite a relatively low external load, requires high inlet pressure due to large mechanical losses of friction between the piston and the cylinder and between the piston rod and gland. These losses depend on the type of seal used, its shape, the material it is made from, pre-clamp, and the operating parameters of the cylinder. Improperly sealed or assembled seals can cause energy losses of up to 25%. Due to the use of moving seals in the hydraulic cylinder, its energy behaviour is completely different compared to the energy behaviour of a rotary motor, which does not have any seals. The friction force connected with the work of the sealing joints and the mechanical efficiency of the cylinder are determined not only by the external load but also by the method of the applicable supply of the cylinder resulting from the throttling structure, and in particular the pressure level generated in the discharge chamber of the cylinder.
Źródło:
Journal of KONES; 2018, 25, 4; 377-384
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metodyka badań i model matematyczny strat ciśnieniowych w silniku hydraulicznym obrotowym
Autorzy:
Maczyszyn, A.
Powiązania:
https://bibliotekanauki.pl/articles/303007.pdf
Data publikacji:
2017
Wydawca:
Wydawnictwo Druk-Art
Tematy:
napęd hydrostatyczny
moce strat energetycznych
silnik hydrauliczny obrotowy
straty ciśnieniowe
sprawność ciśnieniowa
hydrostatic drive
power losses
rotary hydraulic motor
pressure losses
pressure efficiency
Opis:
W artykule przedstawiono sposób określania współczynnika k8 strat ciśnieniowych ΔpMp (oporów przepływu) w kanałach wewnętrznych silnika hydraulicznego SWSB-63, współczynnika wyznaczonego przy natężeniu przepływu równym teoretycznej wydajności QPt pompy zasilającej silnik, strat odniesionych do ciśnienia nominalnego pn układu hydraulicznego. Nawiązano do modelu zachowania energetycznego silnika hydraulicznego obrotowego zaproponowanego przez Z. Paszotę.
The article presents the method of determining the coefficient k8 of pressure losses ΔpMp (flow resistance) in the hydraulic motor channels type SWSB-63. The coefficient determined at the working liquid intensity in the channels is equal to the pump theoretical capacity QPt and losses related to the nominal pressure pn of the hydraulic system. It was related to the energy conservation model of rotary hydraulic engine proposed by Z. Paszota.
Źródło:
Napędy i Sterowanie; 2017, 19, 12; 90-95
1507-7764
Pojawia się w:
Napędy i Sterowanie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the structural and total energy efficiency of selected hydraulic systems with proportional control linear motor
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/247433.pdf
Data publikacji:
2016
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
energy efficiency
power of losses
hydrostatic system
throttling steering
pump
hydraulic linear motor
proportional directional valve
Opis:
In the paper are presented the diagrams of the structural energy efficiency of system with the throttling control assembly and total energy efficiency of the system with constant or variable capacity pump cooperating an overflow valve with the throttling control of the linear hydraulic motor. Diagrams of total energy efficiency of three hydraulic systems working at the same parameters of speed and load of hydraulic linear motor, which were different due to structure and ability of energy saving were presented and compared. This publication also presents analyses and compares the areas of the power fields of energy losses occurring in the elements of three compared hydraulic systems with different structures of the hydraulic linear motor speed control on example on Load Sensing system. The graphical interpretation of the power of losses in the hydrostatic drive and control system elements lets to compare the same power fields of energy losses with other power fields of another structure. This enables to understand what energy losses are the biggest and in which elements of compared hydraulic systems. The best possibility to use in system, as a supply source of the hydraulic cylinder speed series throttling control assembly, is a set consisting of a variable capacity pump cooperating with a Load Sensing (LS) regulator, which totally eliminates the structural volumetric losses in a system. Power ΔPstv of structural volumetric losses is equal to zero, because the current pump capacity QP is adjusted, by the LS regulator, to the current flow intensity QM set by the throttling assembly.
Źródło:
Journal of KONES; 2016, 23, 2; 317-324
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence the applied control structure on energy efficiency of the hydrostatic system
Autorzy:
Skorek, G.
Powiązania:
https://bibliotekanauki.pl/articles/245430.pdf
Data publikacji:
2018
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
energy efficiency
power of losses
hydrostatic system
throttling steering
pump
hydraulic linear motor
proportional directional valve
deck machinery
Opis:
A control system with a proportional directional throttling control valve or a directional control servo valve, controlling a cylinder (linear hydraulic motor) is used in the ship steering gear drive, in the controllable pitch propeller control, in the variable capacity pump control system for hydraulic deck equipment motors or fixed pitch propellers in small ships (for example ferries). The hydraulic system is designed first of all taking into consideration the nominal parameters of the cylinder load and speed. For such parameters, the energy efficiency of the elements and complete system is described. Meanwhile the exploitation conditions can vary in full range changes of the cylinder load and speed coefficients. The article presents a comparison of the energy behaviour of two widespread structures of hydrostatic systems: a standard individual systems with a throttling steering fed by a constant capacity pump. Both hydraulic solutions are described and equations of the total efficiency η of the system are presented. Diagrams of energy efficiency of two hydraulic systems working at the same parameters of a speed and a load of hydraulic linear motor, which were different due to structure are presented and compared, as well ability of energy saving. This publication also presents analyses and compares the areas of the power fields of energy losses occurring in the elements of two hydraulic systems with different structures of the hydraulic linear motor speed control.
Źródło:
Journal of KONES; 2018, 25, 3; 411-418
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł

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