Autor: Gieleta, R - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: The HWKK rheological model for resins
Model reologiczny HWKK dla żywic
Autorzy:: Klasztorny, M.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/281171.pdf
Data publikacji:: 2002
Wydawca:: Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:: polymers
resins
constitutive equations of viscoelasticity
material constans
Opis:: A rheological model for epoxy and polyester resins, denoted with the symbol HWKK, has been developed and positively validated for selected loading programmes. This model describes the first-rank reversible creep of amorphous tyermohardened polymers with good accuracy. The mechanical HWKK model consists of four elements connected in series, formulated by Hooke, Wilczyński and Kelvin. Constitutive equations of viscoelasticity for the HWKK model have been formulated, with fractional and normal exponential functions used as the generating ones. An algorithm for identification of the material constants, based on creep experiments of bar samples uniaxially tensioned, has been developed. The material constants have been identified for epoxy and polyester resins.
Opracowano nowy model reologiczny żywicy epoksydowej i poliestrowej, oznaczony symbolem HWKK. Przeprowadzono walidację tego modelu dla wybranych programów obciążenia, uzyskując pozytywne wyniki. Model HWKK opisuje z dobrą dokładnośćią pełzanie pierwszorzędowe odwracalne polimerów amorficznych termoutwardzalnych. Model ten jest odwzorowany przez cztery elementy mechaniczne połączone szeregowo typu Hooke'a, Wilczyńskiego i Kelvina. Sformułowana równania konstytutywne lepkosprężystości i modelu HWKK stosując jako funkcje tworzące jedną funkcję wykładniczą ułamkową oraz dwie funkcje wykładnicze zwykłe. Opracowano algorytm identyfikacji stałych materiałowych opisujących model HWKK, bazujący na eksperymentach pełzania próbek prętowych rozciąganych osiowo. Stałe te zidentyfikowano dla żywicy epoksydowej i poliestrowej.
Źródło:: Journal of Theoretical and Applied Mechanics; 2002, 40, 4; 939-960
1429-2955
Pojawia się w:: Journal of Theoretical and Applied Mechanics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: Fatigue strength investigation of bonded joints
Autorzy:: Gieleta, R.
Derewońko, A.
Powiązania:: https://bibliotekanauki.pl/articles/243427.pdf
Data publikacji:: 2007
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: adhesive bonded joint
fatigue strength
non-linear analysis
Opis:: Numerous advantages of the bonded joints result in wide application in the aircraft, motor industry or powertrain components. These types of joints enable joining materials with different mechanical properties (e.g. Stiffness) and dimensions without structure change. Proper joint design limits the field of local stress concentrations or even eliminates them. The structural integrity of complete structure depends on the fatigue estimation of the bonded joint. Application of the finite element method to life prediction of the double lap bonded joint metal-composite-metal is presented. Three dimensional numerical models are generated by professional engineering software tools. The contact problem is modelled between the epoxy resin and metal and composite surfaces. A laminated composite consists of the epoxy woven carbon prepreg. Elasto-plastic materials models of the adhesion and metal and orthotropy composite model allowed determining the contact normal stress in the interfaces in each deformation increment which is induced by an external load. MSC.Marc was used to determine the strain and stress distribution in the double lap bonded joint including contact normal stress in the steel/adhesive and laminated composite/adhesive interfaces. Two numerical models of the double lap bonded joint were compared. The use of the presented method is more suitable for structure optimisation than numerical analysis.
Źródło:: Journal of KONES; 2007, 14, 3; 177-186
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: Security improvement for oil and gas pipeline infrastructure
Autorzy:: Małachowski, J.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/244151.pdf
Data publikacji:: 2008
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: security
simulation
modelling
Opis:: This research has been inspired by security concerns due to the recent increase in the terrorist threat to gas and crude oil transportation around the world, especially in regions that are of significant value for the energy supplies. Computational mechanics methods will be used in this research to apply shock wave analysis for possible damage assessment of the affected pipelines. These methods may be also used for pipelines at power plants (especially nuclear), which are usually placed high on the homeland security priority list. The main goal of this research is focused on establishing effective simulation methodology to study the influence of shock waves (caused by explosion) on pipeline systems (buried, on surface, or underwater) to ensure their security. This study is primarily focused on the behaviour of a pipeline subjected to the shock wave produced by the detonation of highly explosive (HE) materials. The results of this study will primarily allow for analysis of the blast wave propagation and the resulting damage inflicted by the pipeline. Outcomes of this research are important in preventing damage progression of pipelines under the blast loading. This data will also be used to develop improved design guidelines for safer and less vulnerable pipelines. The study allows for determining a type of structure of the high energy absorbing protective system.
Źródło:: Journal of KONES; 2008, 15, 2; 295-300
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: Carbon - epoxy composite fatigue strength - experiment and fem numerical estimation
Autorzy:: Derewońko, A.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/246504.pdf
Data publikacji:: 2012
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: fatigue strength
carbon-epoxy composite
FEM
Opis:: The development of composite materials characterized by the constant amelioration of their mechanical properties (stiffness and strength) has widened their application for structural elements, mainly in aeronautical, naval and automobile industries. The possibility of tailoring the composite’s properties appropriately to the applied load (by changing the direction of the fibre alignment and applying a corresponding matrix) results in the growing importance of the design process. The paper presents a numerical technique of determining the fatigue strength of the laminated carbon–epoxy composite. The experimental investigations were carried out to determine the complete set of the stiffness characteristics Eij, Gij, ..ij, the strength characteristics ..i,n, ..i,n. and the S-N fatigue curves. The static and fatigue numerical calculations were carried out for the material anisotropic model of the particular composite layers. Eight-node 3D finite elements with the composite’s properties were used to develop the specimen’s numerical model. The contact problem between the composite layers enabling the reflection of a mutual interaction was taken into account. The numerical investigation also included the state of effort analysis and the fatigue life assessment of the composite. The assessment of the composite’s fatigue life was performed using the MSC.Fatigue code. The verification of models and numerical analysis was carried out for composite specimens made of the CE 8201-245- 45/120 prepreg. The experimental verification confirmed that the places of the lowest fatigue life, found out in numerical analysis, are located in the area of the gauge part.
Źródło:: Journal of KONES; 2012, 19, 3; 103-110
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 5.

Tytuł:: Study of FEM model for tension and compression test for aluminum alloys samples in order to set materiał data
Autorzy:: Zduniak, B.
Morka, A.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/247620.pdf
Data publikacji:: 2010
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: numerical analysis
material data
Johnson-Cook model
P A11
FEM
Opis:: The purpose of this paper is to conform an available material data for aluminum alloy material (P A11). This task was filled with the aid of computer modeling techniques, which are based on Finite Element Method (FEM), and our own experimental tests of quasistatic tension/compression material samples. For this kind of research FEM is most commonly used, but there are also other numerical methods that can be applied. The idea of FEM is the division of the given continuous area into a finite number of subareas (finite elements) connected with one another in nodal points and approximation of solution inside the finite elements using interpolation functions and function values in nodes. Numerical analysis was performed with the LS-Dyna commercial software. Reconstruction of conditions of experiment required application of implicit method of numerical integration in time, so called implicit solver. At this stage of work the aluminum alloy P A11 with respect to Johnson-Cook model was researched. A further work for fmding a good material data for WHA, U12A steel for other constitutive models will be performed. A good agreement of the numerical and experimental results is received. Other material data used in modeling, which were not determined by experiment, assumed according to literature sources.
Źródło:: Journal of KONES; 2010, 17, 3; 527-532
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 6.

Tytuł:: Experimental investigation of deflectors angle influence on energy absorption
Autorzy:: Gieleta, R.
Barnat, W.
Niezgoda, T.
Powiązania:: https://bibliotekanauki.pl/articles/241835.pdf
Data publikacji:: 2012
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: IED
improvised explosive device
hull resistance
deflector
Opis:: Numerical simulations without preliminary validation and model verification are vulnerable to errors. Best results are obtained when full experimental research is provided. Such tests are expensive and may be dangerous. Due to cost control and personnel safety, studies are often done in scale. Scale can affect both construction dimensions and applied load. In this paper four different vehicle's bottoms are examined: flat bottom and 3 types of deflectors. The paper presents four different vehicle's bottom shapes in order to examine deflector angle influence on energy absorption. The test included 4 cases: flat bottom broken-shaped deflector and deflectors with different apex angles 124 centigrade and 144 centigrade. For all cases the distance between explosive and panel was approximately 400 mm. The charge used was 100 g TNT. Flat bottom and deflectors were made of St3 steel with 2 mm thickness. For the purpose of the research a special test stand to examine effects of detonation wave was used. The force measurement system was designed in Department of Mechanics and Applied Computer Science. As a result, force versus time plots were obtained. The use of any deflector decreases maximum force affecting vehicle's hull.
Źródło:: Journal of KONES; 2012, 19, 4; 201-205
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 7.

Tytuł:: Experimental and analytical research on resonance phenomena of vibrating head with MRE regulating element
Autorzy:: Miedzińska, D.
Gieleta, R.
Osiński, J.
Powiązania:: https://bibliotekanauki.pl/articles/265035.pdf
Data publikacji:: 2015
Wydawca:: Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:: vibratory pile hammer
resonance
vibrations
Fourier analysis
analiza Fouriera
wibracje
rezonans
Opis:: A vibratory pile hammer (VPH) is a mechanical device used to drive steel piles as well as tube piles into soil to provide foundation support for buildings or other structures. In order to increase the stability and the efficiency of the VPH work in the over-resonance frequency, a new VPH construction was developed at the Military University of Technology. The new VPH contains a system of counter-rotating eccentric weights, powered by hydraulic motors, and designed in such a way that horizontal vibrations cancel out, while vertical vibrations are transmitted into the pile. This system is suspended in the static parts by the adaptive variable stiffness pillows based on a smart material, magnetorheological elastomer (MRE), whose rheological and mechanical properties can be reversibly and rapidly controlled by an external magnetic field. The work presented in the paper is a part of the modified VPH construction design process. It concerns the experimental research on the vibrations during the piling process and the analytical analyses of the gained signal. The results will be applied in the VPH control system.
Źródło:: International Journal of Applied Mechanics and Engineering; 2015, 20, 1; 201-208
1734-4492
2353-9003
Pojawia się w:: International Journal of Applied Mechanics and Engineering
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 8.

Tytuł:: Numerical and Experimental Research on Stab Resistance of a Body Armour Package
Numeryczne i doświadczalne badania nożo-odporności ochronnego pakietu balistycznego
Autorzy:: Barnat, W
Sokołowski, D
Gieleta, R
Powiązania:: https://bibliotekanauki.pl/articles/233620.pdf
Data publikacji:: 2014
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:: numerical model
dry fabric
aramid fabric
stab resistance
body armour
kamizelka ochronna
model numeryczny
odporność na przekłucie
ochronny pakiet balistyczny
Opis:: In this paper the issue of the stab resistance of a ballistic package is addressed. Emphasis was placed on this issue because most modern vests are designed to meet the threat posed by firearms only. Neglect of protection against melee attacks was also observed. Thus there is a need to develop research methodology for this area, also because it is a valid and necessary problem to be addressed in a modern, developed society. The aim of this study was to create a numerical model which simulated the phenomenon of ballistic package penetration by a test blade. The specification of the test blade was taken from NIJ Standard-0115.00. During the research, stab resistance tests on dry Twaron T750 fabric was carried out on a drop test machine. The test was filmed with a Phantom V12 high-speed camera. A numerical model of the fabric architecture was prepared using commercial LSDYNA software. The numerical model represents the whole research area according to NIJ Standard-0115.00. As backing material, ROMA 1° ballistic clay was used.
Artykuł porusza zagadnienie nożo-odporności pakietów balistycznych stosowanych w kamizelkach ochronnych. Nacisk został położony na to zagadnienie, ponieważ większość nowoczesnych kamizelek zostało zaprojektowane do ochronny przed bronią palną. Zaniedbując ochronę przed atakiem przy użyciu broni białej. Istnieje więc potrzeba wypracowania metodologii w tym zakresie, ponieważ jest to problem ważny w nowoczesnym i rozwiniętym społeczeństwie. Celem badań było wypracowanie modelu numerycznego, który wiernie symuluje zjawisko przebicia pakietu balistycznego przez nóż testowy. Specyfikacja noża testowego została zapożyczona z normy NIJ Standard-0115.00. W trakcie badań zostały przeprowadzone testy nożo-odporności nieprzesyconej tkaniny Twaron T750 przy użyciu kolumny zrzutowej. Testy zostały sfilmowane przy użyciu super szybkiej kamery Phantom V12. Do stworzenia modelu numerycznego tkaniny i późniejszych obliczeń zostały wykorzystane komercyjne oprogramowania LS-DYNA. Model numeryczny odzwierciedlał całą przestrzeń pomiarową zgodnie z normą NIJ Standard-0115.00. Jako podłoża użyto plasteliny balistycznej ROMA 1°.
Źródło:: Fibres & Textiles in Eastern Europe; 2014, 6 (108); 90-96
1230-3666
2300-7354
Pojawia się w:: Fibres & Textiles in Eastern Europe
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 9.

Tytuł:: Experimental investigation of selected explosion parameters for numerical model
Autorzy:: Barnat, W.
Gieleta, R.
Niezgoda, T.
Powiązania:: https://bibliotekanauki.pl/articles/241757.pdf
Data publikacji:: 2012
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: IED
improvised explosive device
numerical model
validation
Opis:: The aim of presented work is examination of blast wave, especially incident and reflected wave pressure. Due to many difficulties and complexity of phenomenon a complete study for different charges should be done. In presented paper two cylindrical TNT charges were used, weighting respectively 100 g and 200 g. Pressure wave was examined using original test stand designed and developed on Department of Mechanics and Applied Computer Science. A test steel test plate with 5 mm thickness was equipped with pressure gauge to measure reflected wave. Additionally, the plate was placed on four special electroresistance strain gauges...To measure force Vishay EA-06-120-060LZ strain gauges were used. For amplification of the dynamometers with strain gauges, MS1001 INFEL bridge was used. The system was used to validate the results from reflected wave pressure gauge. Shock wave pressures was measured using a special sensor model 137A21 amd M350B21 made by PCB Piezotronics At specific distance there was also incident wave pressure gauge. In order to fully examine the dynamic response of the plate an accelerometer was used. As a result, pressure versus time and acceleration versus time plots were obtained. The results will be used to validate numerical model of blast wave impact on a plate.
Źródło:: Journal of KONES; 2012, 19, 4; 9-13
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: Selected aspects of numerical analysis of layered flexible structures subjected to impact of soft core projectile
Szczególne aspekty numerycznej analizy uderzenia pocisków z miękkim rdzeniem w warstwowe struktury wiotkie
Autorzy:: Morka, A.
Kędzierski, P.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/139501.pdf
Data publikacji:: 2015
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: terminal ballistics
penetration
perforation
FEM
finite element method
adaptive method
ballistic composites
balistyka końcowa
penetracja
perforacja
MES
metoda elementów skończonych
metoda adaptacyjna
kompozyty balistyczne
Opis:: The aim of the study is to identify the relevant aspects of numerical analysis of impact of projectiles with soft cores into a package composed of thin flexible plies located on the plastic backing. In order to illustrate the problem, normal impact of 7.62 mm TT projectile into an unclamped package comprising 36 plies of Dyneema SB71 supported on the plastic backing was selected. The problem was solved with the use of the finite element method (FEM) with the explicit integration scheme (central difference method) of motion equations in the matrix form. Based on the conducted numerical computations, it was revealed that obtaining the extreme deformations of a projectile soft core and the backing material in Lagrangian description requires employment of adaptive methods. The proposed R-adaptive method performs its role but must be used carefully due to the mass loss which may appear during calculations.
Przedmiotem pracy jest wskazanie istotnych aspektów numerycznej analizy zagadnienia uderzenia pocisków z miękkim rdzeniem w pakiet cienkich wiotkich warstw ulokowanych na plastycznym położu. W celu ilustracji problemu wybrano normalne uderzenie pocisku 7,6225 mm TT w pakiet 36 warstw Dyneema SB71 swobodnie oparty na podłożu plastycznym. Problem rozwiązano z wykorzystaniem metody elementów skończonych (MES) z jawnym schematem (różnic centralnych) całkowania równania ruchu w formie macierzowej MES. Na podstawie przeprowadzonych analiz wykazano, że uzyskanie ekstremalnych deformacji miękkiego rdzenia pocisku oraz plastycznego podłoża w analizie numerycznej w ujęciu Lagrange’a wymaga zastosowania technik adaptacyjnych. Zaproponowana technika R-adaptive spełnia swoją rolę, ale musi być stosowana z rozwagą ze względu na negatywną cechę powodującą utratę masy modelu.
Źródło:: Archive of Mechanical Engineering; 2015, LXII, 1; 73-83
0004-0738
Pojawia się w:: Archive of Mechanical Engineering
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: Analysis of a protective composite panel with energy adsorbent in the form of foamed aluminium
Autorzy:: Barnat, W.
Panowicz, R.
Niezgoda, T.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/247656.pdf
Data publikacji:: 2010
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: blast wave
analytical model
FE analysis
aluminium panel
Opis:: The article presents the results of the investigations into modelling a blast wave for huge charges of l kg TNT equivalent. Modelling of huge charges is a very interesting problem due to a scale effect. During numerical analyses a detonation phenomenon was ignored (for the reason of the analysis time). The paper considers the effects of the influence of a pressure wave coming from a huge TNT charge (modelled with energy) on a 6 mm thick steel plate as well as on a protective panel made of foamed aluminium with composite layer. A panel of foamed aluminium was used for the protection of the described plate. The particular elements of a panel, subjected to an experimental analysis, were jointed with the use of a glueing method. In the numerical model the particular component layers were jointed with contact. The ALE (Arbitrary-Lagrange-Euler) function was used for coupling between the Euler domain and the Lagrange domain. The method requires absolute location compatibility of the nodes from both jointed areas. In the results of the conducted investigations, the permanent deformation of the steel plate was obtained.. Additionally, the possibility of the steel plate deformation evaluation was considered on the basis of accessible literature. Due to a huge charge, the analysis was performed with the use of the finite element method with the eiperimental verification.
Źródło:: Journal of KONES; 2010, 17, 4; 35-44
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: Investigation of a panel with an elastomer layer plus carbon fibres loaded with a blast wave
Autorzy:: Barnat, W.
Niezgoda, T.
Gieleta, R.
Panowicz, R.
Powiązania:: https://bibliotekanauki.pl/articles/247636.pdf
Data publikacji:: 2010
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: blast wave
experiment
FE analysis
elastomer layer
Opis:: Terrorist attacks are directed against the most important elements of the infrastructure and human life. Crews of the combat vehicles as well as transmission installation of oil, gas and electric energy are, first of all, exposed to such operations. Such a situation caused striving to increase the safety against the activity of short-time loads coming from explosions [l, 2]. The object of the presented investigations was a numerical-experimental analysis of an elastomer layer of the protective panel combined with an experimental verification. Developed elastomer structures constitute perspective materials and will be applied to solve the problems connected with the increase of combat vehicle safety as well as trouble constructions of pipelines and gas pipelines especially in the dangerous places such as passages over rivers. A plate with an elastomer layer (with carbon fibres) loaded with a 100 g TNT charge was subjected to the analysis. The numerical analysis was verified experimentally. The results of the conducted analyses will be applied in further works on the selection of the kinds and parameters of the energy absorbing layers. They will be also used for further validating and optimizing investigations, which will aim at absorbing or dispersion of a maximum great value of energy influencing the energy absorbing panel. Such panels can be used for constructing armoured vehicles and protective elements of stationary strategic constructions. The constructions which can be exposed to damages resulted from a different kind of dynamic forces such as impacts or influences of the pressure wave comingfrom detonation of an explosive material should have the structure enabling absorption of as great as possible part of energy which influences them. Energy absorbing elements are constructed in the form of sandwich structures coats with a specially selected core material. One of the interesting types of materials which can be used for this purpose is elastomer. These materials enable significant increasing of the protective degree due to their capacities of absorbing energy of a blast wave. Applying of these materials results in decreasing of vibrations frequency of a system loaded with a pressure impulse.
Źródło:: Journal of KONES; 2010, 17, 4; 19-26
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 13.

Tytuł:: Influence of the volume fraction of the carbonyl iron particles on the mechanical properties of the magnetorheological elastomers
Autorzy:: Sławiński, G.
Niezgoda, T.
Miedzińska, D.
Gieleta, R.
Powiązania:: https://bibliotekanauki.pl/articles/247437.pdf
Data publikacji:: 2010
Wydawca:: Instytut Techniczny Wojsk Lotniczych
Tematy:: smart materials
magnetorheological elastomer (MRE)
finite element method (FEM)
Opis:: Magnetorheological materials belong to the group of the so called intelligent materials. Their rheological properties can be changed in a large range using an external magnetic field. That is why they fmd ever growing application in modern technical equipment, among others in controlled dampers, clutches, sensors etc. In the paper, a numerical strength analysis of a magnetorheological material was presented. The influence of the volume fraction of carbonyl iron particles (the share of the carbonyl iron particles varied from 1.5 to 33.0 vol. %.) on the mechanical properties of the material were investigated, in particular on the Young's modulus variation. Experimental tests were carried out for specimens made of pure PU 70/30 elastomer with iron particles. They induded uniaxial compression tests. In the farmer case, specimens were in a shape of a cylinder with a diameter of 20 mm and a height of 25-30 mm. The results of experimental tests carried out in order to determine the parameters necessary to build the numerical model were induded in the paper. In the paper, an algorithm developed for determining the parameters for modelling the structure was presented. A fragment of the structure, containing several particles of iron and some quantity of elastomer, corresponding to the assumed volume fractions, was subjected to numerical analysis.
Źródło:: Journal of KONES; 2010, 17, 3; 401-406
1231-4005
2354-0133
Pojawia się w:: Journal of KONES
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 14.

Tytuł:: Numerical and Experimental Studies of Material Properties of Special - Purpose Material Twaron T750
Numeryczne i eksperymentalne badania właściwości materiału specjalnego przeznaczenia Twaron 750
Autorzy:: Barnat, W.
Sokołowski, D.
Gieleta, R.
Bogusz, P.
Powiązania:: https://bibliotekanauki.pl/articles/232404.pdf
Data publikacji:: 2015
Wydawca:: Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:: dry aramid fabric
mechanical properties
finite element analysis
sucha tkanina aramidowa
właściwości mechaniczne
analiza elementów skończonych
Opis:: The subject of this paper is an attempt to define the fundamental constants of materials for special-purpose material - aramid dry faricTwaronT750. During research on this problem, tensile tests of dry fabric TwaronT750 were made on an Istron 8802 strength testing machine. The test was filmed with a Phantom V12 high-speed camera. A numerical model of the fabric architecture was made using commercial HyperMesh and LS-DYNA software. In the numerical model a whole research area was represented.
Tematem tego artykułu jest próba określenia podstawowych stałych materiałowych dla materiału specjalnego przeznaczenia, którym jest tkania aramidowa Twaron 750. W trakcie prowadzonych badań zostały wykonane próby rozciągania nieprzesyconej tkaniny Twaron 750 na maszynie wytrzymałościowej Instron 8802. Próba została sfilmowana przy użyciu szybkiej kamery PHANTOM V12. Model numeryczny oddający architekturę tkaniny został wykonany przy użyciu komercyjnego oprogramowania LS-DYNA. W modelu została odwzorowana cała przestrzeń badawcza rozciąganej próbki.
Źródło:: Fibres & Textiles in Eastern Europe; 2015, 4 (112); 33-38
1230-3666
2300-7354
Pojawia się w:: Fibres & Textiles in Eastern Europe
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 15.

Tytuł:: Crushing behaviour of the PVC foam loaded with beaters of various shapes
Autorzy:: Bogusz, P.
Gieleta, R.
Stankiewicz, M.
Konarzewski, M.
Powiązania:: https://bibliotekanauki.pl/articles/387664.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:: polymer foam
polyvinyl chloride foam
hitting with a blunt object
energy absorption
impact tests
experimental mechanics
Opis:: Statistically, at least 50% of all injuries experienced by police officers in the line of duty are due to assaults with blunt objects. Therefore, vests used by the police should provide not only good ballistic resistance, but also good protection against such threats. Foamed materials are possible to be used for body protectors or inserts of protective clothes. The effects of dynamic impact with beaters of different shapes onto behaviour of polymeric foamed material were determined. There were used four types of beaters: flat, cylindrical, edgy and cornered. Strikes with blunt objects such as a flat board, baseball bat, edgy brick, pavement brick or a sharp stone, to which a protective ware can be subjected, were simulated. The impact load was applied to the rectangular specimens, made of polyvinyl chloride foam, with a usage of a drop hammer. Plots of force versus compression for all the tested samples were obtained and analysed. The effects of impacts with beaters of different shapes onto foamed material samples were presented. A shape of the blunt object significantly influences crushing behaviour of the foamed material. The impact energy of a flat beater is absorbed effectively on a short distance, since it is spread on a relatively large surface. The cylindrical and edgy beaters did not cause fragmentation of the samples, however, on the upper surfaces of the samples, permanent deformations mapping the beaters shapes as well as some cracks occurred. An impact with a sharp object, for example, a cornered beater is very difficult to be neutralized by the foam material, because it is cumulated on a small area.
Źródło:: Acta Mechanica et Automatica; 2018, 12, 1; 23-30
1898-4088
2300-5319
Pojawia się w:: Acta Mechanica et Automatica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Informacja

Wyszukujesz frazę "Gieleta, R" wg kryterium: Autor

Źródło danych

Dostawca treści

Kolekcja

Rok wydania

Wydawca

Temat

Autor

Typ dokumentu

Język