Investigations of the watershield effect on blast waves: One and two-dimensional study

Abstract

The object of this analysis is to investigate the mitigation effects of watershield on blast waves numerically. One application of current work is to resolve the design concerns for the ammunition storage facilities. To verify the numerical procedure using a multimaterial Eulerian finite element method, the results are compared with the available experimental data for detonation in a pressured tank, and the analytical predictions for air shocks. Features of the free-field detonation process are then studied from a series of one-dimensional simulations. The magnitude of peak pressure decreases and shock arrival time increases with increasing thickness of watershield. For design analysis, the case of two-dimensional axisymmetric geometry (a vertical) right-circular cylinder) with a central charge is also considered. The full process including initial detonation, shock wave propagation and reflection from the outer rigid boundary is examined. For the explosives immersed in water, the magnitude of peak pressure becomes smaller than those in air tank without watershield. At later time period, the average gas pressure left in the air tank is about 20 bar.