Numerical Study of Air Frame Behaviour on Fragmentation Pattern in Multi Layered Pre-Formed Fragment Type Warhead of Modern Rockets

Abstract

The artillery rocket system is the sophisticated type of defence system. One of it is Preformed fragment type warhead. The tungsten fragments-ball, needles, cubes etc. are arranged around the charge mass in such a way that on initiation the fragments are propelled with very high velocity by rupturing the ballistic casing. These ballistic casing can be made of different materials according to the aerodynamic loading, structural loads etc. Generally used casing materials are FRP, steel, aluminium. Due to difference in the material properties the fragment velocity, energies and the pressure generated are affected. To study these effect static and dynamic trails prove costly and time consuming. So an alternative method of simulation of warhead with different ballistic casing is presented. During simulation the multilayer fragments are replaced by single layer having equivalent mass as it is difficult to model 20000 no of fragments. Hence the results obtained are in good agreement with the available data.