Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Morka, A." wg kryterium: Autor

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 23
Tytuł:
Comparison of numerical and experimental study of armour system based on alumina and silicon carbide ceramics
Autorzy:
Chabera, P.
Boczkowska, A.
Morka, A.
Kędzierski, P.
Niezgoda, T.
Oziębło, A.
Witek, A.
Powiązania:
https://bibliotekanauki.pl/articles/202054.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ballistic performance
numerical simulation
armour
alumina ceramic
silicon carbide ceramic
ceramic-elastomer composites
wydajność balistyczna
symulacja numeryczna
zbroja
kompozyt ceramika-elastomer
Opis:
The main goal of this numerical and experimental study of composite armour systems was to investigate their ballistic behaviour. Numerical simulations were employed to determine the initial dimensions of panel layers before the actual ballistic test. In order to achieve this aim, multivariate computations with different thicknesses of panel layers were conducted. Numerical calculations were performed with the finite element method in the LS-DYNA software, which is a commonly used tool for solving problems associated with shock wave propagation, blasts and impacts. An axisymmetric model was built in order to ensure sufficient discretization. Results of a simulation study allowed thicknesses of layers ensuring assumed level of protection to be determined. According to the simulation results two armour configurations with different ceramics have been fabricated. The composite armour systems consisted of the front layer made of Al2O3 or SiC ceramic and high strength steel as the backing material. The ballistic performance of the proposed protective structures were tested with the use of 7.62 mm Armour Piercing (AP) projectile. A comparison of impact resistance of two defence systems with different ceramic has been carried out. Application of silicon carbide ceramic improved ballistic performance, as evidenced by smaller deformations of the second layer. In addition, one of armour systems was complemented with an intermediate ceramic-elastomer layer. A ceramic-elastomer component was obtained using pressure infiltration of gradient porous ceramic by elastomer. Upon ballistic impact, the ceramic body dissipated kinetic energy of the projectile. The residual energy was absorbed by the intermediate composite layer. It was found, that application of composite plates as a support of a ceramic body provided a decrease of the bullet penetration depth.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2015, 63, 2; 363-367
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of true stress in engineering materials using optical deformation measurement methods
Autorzy:
Bogusz, P.
Popławski, A.
Morka, A.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/241743.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
true stress
optical deformation measurement
experimental studies
FEM
steel
Opis:
The aim of the paper is to evaluate a method of determining true stress in the steel sample subjected to static axial tensile on a universal testing machine. The tensile specimens were made of steel ST3, which was chosen because of its relatively high plastic deformations. Strain measurement was performed using traditional extensometers and additionally a non-contact optical deformation measuring system. Material properties were obtain by the extensometer measurements. The optical equipment registered the investigated sample through the optical system composed of two cameras and calculated a three-dimensional model of the material deformation in time. Displacement fields in axial and radial directions were determined with Digital Image Correlation method (DIC). Then the logarithmic axial strain map and radius shrinkage map in the area of the neck were obtained. Characteristic dimensions of the neck: curvature and width were also measured. It allowed determination of cross-section area changes in the real time, and in the result, calculation of actual true stress in the material during failure process. In this case Bridgman's and other scientists' formulas of stress distribution in the neck were applied. A numerical model, where material properties of finite elements were described by the Johnson-Cooke material model, was developed in LS-PrePost software. The FEM model was computed in LS-DYNA solver. The output tensile curve and neck curvature radius were compared with relevant data obtained from the optical measuring system.
Źródło:
Journal of KONES; 2012, 19, 4; 53-64
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and numerical investigation of energy absorption elastomer panel with honeycomb structure
Autorzy:
Bogusz, P.
Popławski, A.
Morka, A.
Stankiewicz, M.
Sławiński, G.
Powiązania:
https://bibliotekanauki.pl/articles/246847.pdf
Data publikacji:
2015
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
energy absorption structure
blast shock wave
numerical modelling
elastomer
validation
Opis:
The paper presents a prototype design of elastomer energy absorbing panel made in a shape of honeycomb structure. The proposed panel was installed in a protected plate and tested on a specially designed test stand, where a shock wave from a small explosive charge was applied. The elastomer honeycomb structure was compared with a version of the panel made of solid elastomer materials, the same as used in the honeycomb structure and also with a protected plate without any panels. During the research, acceleration in the middle part of each investigated protected plate was recorded. The protected plates were scanned after the tests in order to measure their maximum deformation. Acceleration graphs and maximum deflections of all three considered structures were compared. The obtained results were used to validate numerical models of the designed structures and the test stand. A discreet model of the test stand and models of elastomer panels were developed with HyperMesh FEM software using shell and solid elements. The materials were described using a tabulated Johnson-Cook model and constitutive model for the rubber parts; all available in the material library of Ls-Dyna software. The blast loading was simulated using the CONWEP method. This model generates a boundary condition, based on the experimental data and TNT equivalent mass, which substitutes the wave propagation with a pressure. Finally, the experimental results of acceleration and deformation of the plates were compared with the corresponding results of the numerical analyses carried out using finite element method. The numerical models can be utilised in the future research as a virtual range stand. The developed elastomer honeycomb structure can be modified to meet various requirements of ballistic protection levels, by applying elastomer of different stiffness or optimizing shape and dimensions of the honeycomb structure.
Źródło:
Journal of KONES; 2015, 22, 4; 29-36
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling and numerical simulation of the protectiye shield - protected plate - test stand system under blast shock wave
Autorzy:
Klasztorny, M.
Dziewulski, P.
Niezgoda, T.
Morka, A.
Powiązania:
https://bibliotekanauki.pl/articles/242616.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
light armoured vehicle
protective shield
aluminium-hybrid laminate-foam shield
blast shock wave
modelling and simulation
Opis:
The study presents FE modelling and simulation of a system for range testing of protective shields for light armoured vehicles. The protective shield designed by Authors is used against HE mines and IEDs up to 10 kg TNT. The system consists of the multiple-use portable rangę stand, a protected Armox 500T steel plate and a protective shield. The shield has a multi-layer structure and has the following main layers: PA11 aluminum, SCACS hybrid laminate, ALPORAS aluminum foam, SCACS hybrid laminate, connected together using SOUDASEAL chemo-set glue. The HE spherical charge is suspended centrally at 400 mm distance from the top surface of the stand. Overall dimensions of the test stand are approximately 800x800x180 mm, the protected piąte has dimensions 650x650x5 mm, and the protective shield is of 450x450x76 mm dimensions. The system is supported by an additional steel plate stiffening the subsoil. FE modelling, numerical simulations and processing the results were performed for the system under blast shock wave using the following CAE systems: CATIA, HyperMesh, LS-Dyna, and LS-PrePost. The 8-nodes brick finite elements were used, taking into account friction and contact phenomena. Isotropic and orthotropic material models and advanced nonlinear equations-of-state for some parts of the system were chosen, with relevant failure and erosion criteria, including the Johnson — Cook model for Armox 500T steel and PA11 aluminum and the MAT 161 model for plies of hybrid laminates. The shock wave was modelled approximately using the LOAD BLAST ENHANCED option available in LS-Dyna Version 971 R4 Beta code. Numerical simulations were performed for 2 kg TNT.
Źródło:
Journal of KONES; 2010, 17, 3; 197-204
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analyses of ceramic/metal ballistic panels subjected to projectile impact
Autorzy:
Morka, A.
Nowak, J.
Powiązania:
https://bibliotekanauki.pl/articles/242960.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
impact problem
armour perforation
ballistic resistance
ceramic armour
Opis:
The paper concerns research and development on modern, ceramic-based, protective layers used in the armour of tanks, combat vehicles and aeroplanes. A task of ceramic panels is reduction and dispersion of localized kinetic energy before a projectile or its fragment approaches the interior of protected object. The numerical investigations have been performed to determine the ballistic resistance of ceramic/metal panels subjected to projectile impact. The impact of the 7.62mm armour-piercing projectile on the ceramic elements backed by a metal plate was analyzed. The tested panels were composed of a ceramic layer (Al2O3, SiC or B4C) and a metal layer (7017 aluminium alloy, Armox 500T steel or Ti6Al-4 titanium alloy). Different shapes of ceramic elements were analyzed, including hemispheres and pyramids, with respect to standard flat tiles. The influence of the impact point location was also taken into considerations. The computer simulations were performed with the Finite Element Method implemented in LS-DYNA code. Full 3D models of the projectile and targets were developed with strain rate and temperature dependent material constitutive relations. The conclusions presented in the paper can be applied to develop modern impact protection panels in which the appropriate balance between the mass and protection level must be accomplished.
Źródło:
Journal of KONES; 2012, 19, 4; 465-472
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of a multi - component ballistic panel
Autorzy:
Stanisławek, S.
Morka, A.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/243005.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
ballistic protection
composite armour
ceramics
Opis:
The paper presents a numerical study of a two layer composite panel impacted by an AP (Armour Piercing) 14.5x118mm B32 projectile. The panel consists of a number of pyramid ceramic components supported by an aluminium plate. The studied model is compared with a reference structure in which ceramic layer is in a form of a plate. The problem has been solved with the usage of modelling and simulation methods as well as a finite elements method implemented in LS-DYNA software. Space discretization for each option was built with three dimension elements guaranteeing satisfying accuracy of the calculations. For material behaviour simulation, specific models including the influence of the strain rate and temperature changes were considered. A steel projectile and aluminium plate material were described by Johnson-Cook model and a ceramic target by Johnson-Holmquist model. In the studied panels, the area surrounding back edges was supported by a rigid wall. The obtained results show interesting properties of the examined structures considering their ballistic resistance. All tests have given clear results about ballistic protection panel response under AP projectile impact. Panels consisting of sets of pyramids are slightly easier to penetrate. Despite this fact, a ceramic layer is much less susceptible to overall destruction what makes it more applicable for the armour usage. Furthermore, a little influence of the projectile impact point and consequently a part of the pyramid, which is first destroyed, is proved.
Źródło:
Journal of KONES; 2012, 19, 4; 585-588
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of an influence of ceramic plate surrounding by metal components in a ballistic panel
Autorzy:
Stanisławek, S.
Morka, A.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/247100.pdf
Data publikacji:
2011
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
ballistic protection
composite armour
ceramics
Opis:
The paper presents a numerical study of the three layer composite panels impacted by an AP (Armor Piercing) 7.62x51mm projectile. The standard panel is built with aluminum and Al2O3 ceramic plate. The studied model, however, consists of the same aluminum plate but the ceramic one is surrounded by a steel packet. The problem has been solved with the usage of the modelling and simulation methods as well as finite elements method implemented in LS-DYNA software. Space discretization for each option was built with three dimension elements guaranteeing satisfying accuracy of the calculations. For material behaviour simulation, specific models including the influence of the strain rate and temperature changes were considered. Steel projectile and aluminum plate material were described by Johnson-Cook model and ceramic target by Johnson-Holmquist model. In the studied panels, the area surrounding back edges was supported by a rigid wall. The obtained results show interesting properties of the new structures considering their ballistic resistance. The ballistic protection of a three layer panel under the WC projectile impact is indentified. Panels containing the ceramic plate surrounded at each side by a steel packet plate are stronger. However, this difference reaches only the level of 2.4% regardless erosion parameters. Definitely technological complication and an area density mass increase cannot balance a small improvement of ballistic protection. However, this kind of panel is not suggested as a useful solution. Further investigations are suggested in order to analyze an influence of initial ceramic compression. The results of those numerical simulations can be used for designing of modern armour protection systems against hard kinetic projectiles.
Źródło:
Journal of KONES; 2011, 18, 4; 471-474
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical and experimental study of armour system consisted of ceramic and ceramic- elastomer composites
Autorzy:
Chabera, P.
Boczkowska, A.
Morka, A.
Niezgoda, T.
Oziębło, A.
Witek, A.
Powiązania:
https://bibliotekanauki.pl/articles/200348.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ballistic performance
numerical simulation
ceramic
wydajność balistyczna
symulacja numeryczna
ceramiczny
Opis:
The paper presents numerical and experimental results in the study of composite armour systems for ballistic protection. The modelling of protective structures and simulation methods of experiment as well as the finite elements method were implemented in LS DYNA software. Three armour systems with different thickness of layers were analyzed. Discretization for each option was built with three dimensional elements guaranteeing satisfactory accuracy of the calculations. Two selected armour configurations have been ballistically tested using the armour piercing (AP) 7.62 mm calibre. The composite armour systems were made of Al2O3 ceramics placed on the strike face and high strength steel as a backing material. In case of one ballistic structure system an intermediate ceramic- elastomer layer was applied. Ceramic- elastomer composites were obtained from porous ceramics with porosity gradient using pressure infiltration of porous ceramics by elastomer. The urea-urethane elastomer, as a reactive liquid was introduced into pores. As a result composites, in which two phases were interconnecting three-dimensionally and topologically throughout the microstructure, were obtained. Upon ballistic impact, kinetic energy was dissipated by ceramic body The residual energy was absorbed by intermediate composite layer. Effect of the composite shell application on crack propagation of ceramic body was observed.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 4; 853-859
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical Aspects of Penetration Simulation
Autorzy:
Morka, A.
Zduniak, B.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/403496.pdf
Data publikacji:
2011
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
computer simulations
EFG
SPH
FEM
penetration problem
model validation
Opis:
Several numerical methods were studied as means of solution to a penetration problem. The Element Free Galerkin (EFG), Smooth Particle Hydrodynamics (SPH), Finite Element Analysis (FEA) methods were considered. The above mentioned algorithms implemented in the LS-DYNA code were applied. Additionally, the mesh density was taken into consideration. The reference case assumed an average node to node distance of 1 mm. The finer and coarser mesh densities were analysed. The full 3D models of the projectile and target were developed with a strain rate and temperature dependent material constitutive relations. An impact of 12.7x108 mm B32 armour piercing projectile on a 80 mm thick block of 7017 aluminium alloy was modelled. The results obtained by a computer simulation were validated and then verified by experimental data. The study of the erosion criteria involves defining the most efficient and reliable way of removing the failed and extremely deformed parts of the projectile and targets. Generally, EFG method applied to solve the perforation/penetration problems can be characterized as a very stable, reliable and effective method.
Źródło:
Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa; 2011, 2, 3 (5); 21-30
2081-5891
Pojawia się w:
Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modeling of auxetics in structure strength
Autorzy:
Stanisławek, S.
Morka, A.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/241667.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
auxetics
negative Poisson's ratio
material engineering
Opis:
The paper deals with computer simulations of mechanical behaviour of a no-void ideal auxetic isotropic material. Current literature offers wide range of models which resemble the manufactured or natural structures. However, it does not answer the question how a change into auxetic no-void state would affect the continuum effective mechanical properties. Auxetic with the Poisson ratio -0.3 has been compared through typical tests to a classic steel elastic material. Most of the engineering software cannot precede Poisson ratio helow zero. Therefore a unique technique was applied using equation of state to overcome this obstacle. All simulations have been done in elastic regime. For the tensile compression tests a 10 mm edge cube was modelled, the bending test used a 5x5x250 mm bar. The loading for initial tests was realized as a kinematic displacement of particular nodes. For bar bending a force was applied in the middle of the beam. The finite element method has been used with explicit time integration algorithm implemented in commercial software with one integration point brick elements. Specific properties have been observed for each test, for tensile test auxetic showed higher strength while for compression material was weaker. Logically the bending test showed no clear influence of negative Poisson to material strength. Further simulations as a shear or impact tests are planned.
Źródło:
Journal of KONES; 2010, 17, 4; 459-462
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical modelling and design of ALFC shield loaded by 20 MM FSP fragment
Autorzy:
Klasztorny, M.
Świerczewski, M.
Dziewulski, P.
Morka, A.
Powiązania:
https://bibliotekanauki.pl/articles/241865.pdf
Data publikacji:
2012
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
light armoured vehicles
passive protection
IED
FSP
modelling
simulation
design
Opis:
The study develops numerical modelling and design of the ALFC shield loaded by the 20 mm 54 g FSP fragment moving at impact velocity of 1800 m/s (fragmentation simulation of IED devices), used to protect 5 mm-thick Armox 500T steel plate. The ALFC shield is composed of the ALF energy-absorbing subsystem and a 99.7% Al2O3 alumina ceramic layer. The ALF subsystem is designed to absorb blast wave impact energy induced by explosive materials up to 10 kg TNT. The ceramic layer is aimed at stopping FSP fragments. The 5 mm-thick Armox 500T steel plate reflects the body bottom segment of a light armoured vehicle. The main purpose of the study is to determine the minimum thickness of the ceramic layer at which the 5 mm-thick Armox 500T steel plate is fully protected from perforation. The ALF subsystem has the following layered structure: Al2024 aluminium alloy plate, SCACS hybrid laminate plate, ALPORAS aluminium foam, SCACS hybrid laminate plate. The layers are joined with Soudaseal 2K chemoset glue. SCACS hybrid laminate contains the following components: VE 11-M modified vinylester resin (matrix), SWR800 glass S plain weave fabric, Tenax HTA40 6K carbon plain weave fabric, Kevlar 49 T 968 aramid plain weave fabric. The total thickness of the ALF shield amounts to 76 mm. In the numerical modelling, the aluminium alloy plate and Armox 500T steel plate are working in the elasto-plastic range according to Johnson–Cook model. The 99.7% Al2O3 alumina ceramic is working in elasto--hort range according to JH-2 Johnson-Holmquist model. The simulations correspond to large displacements, large deformations and contact among all the components of the system. In FE mesh, the 8-node 24 DOF hexahedral finite elements with single integration point have been used. Additional failure criteria governing ad-hoc erosion of finite elements have been applied. The FEM modelling, simulation and postprocessing have been carried out using Catia, HyperMesh, LS-DYNA and LS-PrePost systems. The simulation results are presented in the form of displacement - perforation contours and the FSP final deformation for both the FSP–shield-plate and the FSP-plate systems. It has been pointed out that 18 mm-thick ceramic layer protects the LAV body bottom plate from perforation.
Źródło:
Journal of KONES; 2012, 19, 4; 301-313
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical study of the projectile trajectory disturbing during the oblique impacts
Autorzy:
Morka, A.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/244096.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
impact problem
armour perforation
ballistic resistance
oblique impact
Opis:
The numerical investigations have been performed to determine the effect of the projectile trajectory disturbing during oblique impacts. An impact of the 14.5x118 mm B32 armour piercing projectile on the A12O3 different shape elements backed by 7017 aluminum alloy plate was analyzed. The oblique impact was realized by different shapes of the frontal ceramic elements, including hemispheres and pyramids, with respect to standard flat tiles. The influence of the impact point location was also under considerations. The Computer simulations were performed with the Element Free Galerkin Method (EFG) implemented in LS-DYNA code. full 3D models of the projectile and targets were developed with strain rate and temperature dependent material constitutive relations. The Johson-Cook model was applied to describe the metallic parts, while the ceramic was modelled by Johnson-Holmquist constitutive relations. The models of the projectile, ceramic and aluminium alloy targets were validated with utilization of the experimental datafound in literature. The obtained results confirmed that the projectile trajectory undergoes essential deviation because of the projectile angular velocity. The conditions for maximizing the value of this angular velocity were studied and it is possible to reach several radians per millisecond. The conclusions presented in this paper can be applied to develop modern impact protection panels where the appropriate balance between the mass and protection level must be accomplished.
Źródło:
Journal of KONES; 2010, 17, 3; 307-312
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical study of the shape effect in the ceramic based ballistic panels
Autorzy:
Morka, A.
Jackowska, B.
Niezgoda, T.
Powiązania:
https://bibliotekanauki.pl/articles/245901.pdf
Data publikacji:
2009
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
impact problem
armour perforation
ballistic resistance
ceramic armour
Opis:
The numerical investigations have been performed to determine the front surface shape effect in the cer based armour systems. Different shapes of ceramic elements were analyzed, including hemispheres and pyramids with respect to standard flat tiles. The influence of the impact point location was also under considerations. The Computer simulations were performed with the Element Free Galerkin Method (EFG) implemented in LS-D code. An impact of the 14.5xll8mm B32 armour piercing projectile on the A12O3 different shape elements backe 7017 aluminium alloy plate was analyzed. Full 3D models of the projectile and targets were developed with strain, rate and temperature dependent material constitutive relations. The models of the projectile, ceramic and aluminium alloy targets were validated with utilization of the experimental data found in literature. The obtained results confirm, the preliminary presumptions, that the shape of the front surface can significant role in the overall ballistic resistance of the panel. Particularly projectile-target initial contact area st to be important factor as showed by impact point location analysis. The conclusions presented in this paper can be applied to develop modern impact protection panels where the appropriate balance between the mass and protection level must be accomplished.
Źródło:
Journal of KONES; 2009, 16, 4; 539-548
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numeryczna analiza optymalizacji na przykładzie uderzenia cylindra w nieodkształcalną przeszkodę
A cylinder impact on rigid wall as an example of numerical optimization analysis
Autorzy:
Morka, A.
Jackowska, B.
Powiązania:
https://bibliotekanauki.pl/articles/209998.pdf
Data publikacji:
2010
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
mechanika
inżynieria mechaniczna
optymalizacja
CAE
modelowanie komputerowe
metoda elementów skończonych
mechanics
mechanical engineering
optimization
computer modelling
finite element method
Opis:
W pracy przedstawiono podstawowe zasady formułowania problemu optymalizacji w inżynierii mechanicznej. Omówiono metody i techniki poszukiwania optymalnych rozwiązań dostępne w pakiecie LS-OPT. Możliwości tego pakietu w praktyce zostały sprawdzone dla przykładowego zagadnienia maksymalizacji absorpcji energii uderzenia aluminiowego cylindra w nieodkształcalną przeszkodę. Rozważano dwie zmienne optymalizacyjne: promień cylindra oraz grubość jego ścianki. Ponadto nałożono warunek ograniczający siłę działającą na uderzaną ściankę do określonej wartości. Obliczenia wykonano, wykorzystując sprzężenie LS-OPT z TrueGrid (modyfikacja geometrii) oraz LS-DYNA (zasadnicza analiza MES). W wyniku przeprowadzonej analizy uzyskano zbieżne rozwiązania spełniające zadane warunki, potwierdzając tym samym przydatność omawianego narzędzia.
The fundamental rules for optimization problem formulating in mechanical engineering were presented in this work. The optimizing methods and techniques implemented in LS-OPT soft ware package were discussed. The case study of maximizing absorbed energy during an aluminum cylinder impact on the rigid wall was analyzed to testify the capabilities of this soft ware. Two design variables were considered, radius and cylinder thickness. Furthermore, the constraint was applied to limit the maximum normal force on the rigid wall. The analysis was performed by LS-OPT coupled with TrueGrid (shape optimization) and LS-DYNA (basic FEA). As the results, the convergent solutions were obtained realizing assumed conditions. It was proved that the LS-OPT package can be considered as a very useful tool for CAE problems.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2010, 59, 3; 219-235
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the modelling of penetration/perforation problems
Autorzy:
Morka, A.
Powiązania:
https://bibliotekanauki.pl/articles/246015.pdf
Data publikacji:
2010
Wydawca:
Instytut Techniczny Wojsk Lotniczych
Tematy:
computational mechanics
impact problem
armour perforation
penetration
ballistic resistance
Opis:
The aim of this paper was to present the main aspects of the numerical modelling within the scope of penetration/perforation problems. The most important stages of the computer model development were discussed in detail. They include the study of the hypervelocity impact physics, selection of the numerical solution method, problem discretization in time (time step) and space (mesh/grid), constitutive models consideration, Initial Boundary Conditions (IBC) and finally choice of the results form for analysis and discussion. The Computer simulations were performed with the Element Free Galerkin Method (EFG) implemented in LS-DYNA code. An impact of the 12. 7x108 mm B32 armour piercing projectile on the selected targets was analyzed. Full SD models of the projectile and targets were developed with strain rate and temperature dependent material constitutive relations. The models of the projectile, ceramic and aluminium alloy targets were validated with utilization of the experimental infield tests and data found in literature. The obtained results confirm that EFG method can be considered for numerical solving of the penetration/perforation problems. The errors in Depth of Penetration have not exceeded 20% as compared numerical and experimental results. The conclusions presented in this paper can be applied to develop modern impact protection panels where the appropriate balance between the mass and protection level must be accomplished.
Źródło:
Journal of KONES; 2010, 17, 1; 291-297
1231-4005
2354-0133
Pojawia się w:
Journal of KONES
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 23

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies