Numerical simulation of the mechanical initiation of liquid explosive systems

The minimum initiation energy is studied numerically as a function of the thickness of a layer of viscous explosive liquid placed in a narrow gap between the plane-parallel surfaces of a striker and an anvil. The statement of the problem simulates the conditions for actual tests of explosives for impact sensitivity. For a given impact force, a layer of liquid with a “soft” type of mechanical behavior is found to exist, which most rapidly acquires energy from a striker and is heated through viscous dissipation of the mechanical energy. It also forms a layer of critical thickness that is characterized by an absolute minimum in the initiation energy. The existence of a layer with a “hard” type of mechanical behavior in the test samples explains the intrinsically nonmonotonic dependence.