A 3D Simulation Methodology for Predicting the Effects of Blasts on a Vehicle Body 2019-01-1033

Triggered explosions are increasingly becoming common in the world today leading to the termination of precious lives under the most unexpected circumstances. As most often ordinary citizens are the targets, there is a great need to design countermeasures in open areas as well as in mobility systems to minimize the destructive effects of such explosive-induced blasts. It would be rather difficult and to an extent risky to carry out physical experiments on the effects of blasts in real world scenarios. The problem is essentially one of fluid-structure interaction in which pressure waves in the surrounding air are triggered by detonating an explosive charge which then have the potential to cause severe damage to any obstacle on the path of the high-energy waves. An alternative and more instructive approach would be to use an advanced simulation technique such as an ALE (Arbitrary Lagrangian Eulerian)-based nonlinear finite element formulation. It has been observed by the present authors that the current reported explorations in this area are primarily laboratory testing of structural components such as a circular plate subjected to a blast causing an axisymmetric pressure pulse, supplemented with an axisymmetric or a 2D finite element analysis. In the present study, keeping in mind the need for evaluating the effect of an arbitrarily located blast on a complex system such as a passenger car, a 3D finite element modelling approach has been initially developed for capturing the effect of a blast on a clamped circular plate made of mild steel. The effectiveness of the 3D simulation methodology is established through good predictions of plate deformation for a number of published physical test results. The study is then extended to simulations of effects of blasts of different intensities and dispositions on a passenger car represented by a previously-validated finite element model.