Numerical simulation of non-energetic reactive armors

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2017
Kurt, Mert Can
Non-energetic reactive armors (NERAs) are one type of reactive armors which are developed to reinforce main armors of heavily armoured vehicles. Non-energetic reactive armors also called as bulging armors are known to be effective against lethal effects of shaped charges. Their structures are like sandwich structures and consist of one intermediate layer between two outer metal plates. The intermediate layer is made of inert materials such as rubber or polymers. The intermediate layer and the outer metal plates are fundemental components of defensive mechanism of these armors. The principle of the mechanism depends on shock waves which are generated by the interaction of a shaped charge jet and the intermediate layer. When the shaped charge jet hits the intermediate layer, high pressure waves are generated which cause a localized bulging of the metallic layers. These metallic layers are accelerated by the shock waves and they distort the movement of the shaped charge jet. This thesis involves numerical simulations of the bulging armors and focuses on the investigation of high performance bulging armors (NERA-Non-energetic reactive armor). In this study, penetration of shaped charges into NERAs is simulated by using AUTODYN software. The simulations are performed in two consecutive steps which are respectively the formation of the jet and the penetration of the jet into the bulging armor. Two-dimensional multi material Euler solver of AUTODYN is chosen for the jet formation analysis. Then this jet is remapped to two and three-dimensional Lagrange solver for the jet penetration analysis. Critical material parameters of the intermediate layer that influence the performance of the armor are studied. 

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Citation Formats
M. C. Kurt, “Numerical simulation of non-energetic reactive armors,” M.S. - Master of Science, Middle East Technical University, 2017.