Characteristics of Shock Wave Propagating over Particulate Foam

For many applications where solid and heavy protections against blast are inoperative, the mitigation of the blast wave loading in a cost-effective manner could be achieved using aqueous foam. The protective behavior of aqueous foam is mainly ascribed to high compressibility of the gas bubbles, which is generally accomplished with energy losses due to side wall friction, viscous losses, evaporation, foam shattering and acceleration of the resulted droplets [1, 2, 3]. As transient processes, these factors introduce uncertainty into the predicted behavior of the foam based protection [4]. Recently it has been established that solid additives slow down the foam decay due to the increase in the liquid viscosity [5, 6] as well as enhance the mitigation performance of the foam barriers [7]. A diversity of physical mechanisms responsible for the final effect complicates the issue, and to obtain reliable data, one has to use specially designed tests.