Pressure relaxation in a hole surrounded by a porous and permeable rock

The problem of explosion in a hole surrounded by a porous medium is considered. Integral equations describing pressure relaxation in the hole due to gas filtration into the surrounding porous space are obtained within the framework of plane one-dimensional, radial, and spherical formulations. An analysis of numerical solutions of these equations shows that the characteristic time of pressure relaxation in the hole depends weakly on its initial value.