Attenuation of shock waves by using porous media

Shock waves generated by explosions cause widespread damage. There is a need to attenuate the peak over pressure produced by these waves. There many methods to do this, and one of the methods is to used porous media. In this paper attenuation of shock waves using porous media is studied both numerically and experimentally. The commercial finite element code COMSOL Multiphysics is used for numerical studies and a hand operated shock tube for experimental studies. Metal wire meshes and perforated sheets with different porosities are used. The numerical studies show that for porosity varying from 47% to 87%, the reduction in peak pressure is 25.7% to 9.9% respectively. Experimentally it found that the reduction in peak shock wave pressure decrease with increase porosity. The reduction in peak pressure not only depends on porosity, but also on shape and size of holes in case of perforated plates. For perforated plates with 3- and 4- mm diameter holes the pressure drop is 13% and 15.2%.