Multiple shock wave reflections during an explosion in a closed volume with shielded walls

The impact of a shield made of granulated material on attenuation of a shock wave multiply reflected from walls is investigated during an explosion inside a closed volume. We performed experiments in a shock tube with a short high-pressure chamber. A low-pressure chamber was filled with air at atmospheric pressure. The flat blast wave with the reducing pressure profile was created. We discovered the dependence of the pressure reduction at a reflected wave front on a distance between the protecting shield and a closed end of the shock tube.