Wyniki wyszukiwania - BazTech

1

Experimental and numerical investigation of energy absorption elastomer panel with honeycomb structure

Bogusz P., Popławski A., Morka A., Stankiewicz M., Sławiński G.

Journal of KONES

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2015

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Vol. 22, No. 4

29--36

EN

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.

2

Ochrona pojazdów wojskowych przed wybuchem min i improwizowanych urządzeń wybuchowych

Niezgoda T., Sławiński G., Gieleta R., Świerczewski M.

Journal of KONBiN

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2015

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No. 1 (33)

123--134

PL

Pojazdy wojskowe są narażone na działanie m.in. fali wybuchowej min oraz improwizowanych urządzeń wybuchowych IED (z ang. improvised explosive device). Dotychczasowe rozwiązania konstrukcyjne pancerzy pojazdów wojskowych nie zapewniają ich ochrony na maksymalnym poziomie. W publikacji przedstawiono rozwiązania konstrukcyjne, których celem jest zwiększenie odporności pojazdów wojskowych na eksplozję ładunków wybuchowych. Ponadto scharakteryzowano wymagania dotyczące odporności pojazdów wojskowych na wybuch min i urządzeń IED. Przedstawiono również przykładowe wyniki badań paneli energochłonnych oraz sformułowane na ich podstawie wnioski do dalszego rozwoju konstrukcji ochronnych.

EN

Military vehicles are exposed, among others, to mine and IED (Improvised Explosive Device) threats. Contemporary structural solutions cannot ensure their safety at maximum level. This paper presents a review of currently used structural solutions enhancing protection level against explosion. Furthermore, requirements for military vehicles safety against mine and IED threats are characterized. As well as that, sample results of energy absorbing panels examination results are shown. On this basis remarks to further development of protective structures are formulated.

3

Numerical Modelling, Simulation and Validation of the SPS and PS Systems under 6 kg TNT Blast Shock Wave

Świerczewski M., Klasztorny M., Dziewulski P., Gotowicki P.

Acta Mechanica et Automatica

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2012

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Vol. 6, no. 3

77-87

EN

The paper develops a new methodology of FE modelling and simulation of the SPS and SP systems under 6 kg TNT blast shock wave. SPS code refers to the range stand – protected plate – protective shield ALF system, while PS code refers to the range stand – protected plate system. The multiple – use portable range stand for testing protective shields against blast loadings was developed under Research and Development Project No. O 0062 R00 06. System SPS uses high strength M20 erection bolts to connect the protective shield to the protected plate. In reference to the SPS system, validation explosion test was performed. It has pointed out that the developed methodology of numerical modelling and simulation of SPS and PS systems, using CATIA , HyperMesh, LS-Dyna, and LS-PrePost software, is correct and the ALF protective shield panels have increased blast resistance and high energy – absorption capability

4

Modelling and numerical simulation of the protectiye shield - protected plate - test stand system under blast shock wave

Klasztorny M., Dziewulski P., Niezgoda T., Morka A.

Journal of KONES

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2010

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Vol. 17, No. 3

197-204

EN

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.