Explosion initiation during the collapse of a gas cavity into a solid explosive layer

The case of an impact on a thin annular layer of incompressible viscoplastic material with a cavity filled with gas is considered. The layer is placed in a rigid assembly such as a press mold and is compressed by a piston at a constant speed. The solution of the corresponding strength problem is performed by a semi-inverse method with the specification of the rod type of medium flow and the governing equations of the viscoplastic substance. The obtained data on the accelerated motion of the cavity walls are considered as an example of focusing (energy accumulation) in a converging flow. Information on the temperature distribution under a load on the layer is used to calculate the parameters of explosion initiation by an impact on a ring charge of a solid explosive. The possibility of thermal ignition of reactive substances without the participation of self-heating and only due to dissipative heating due to the energy of mechanical action is discussed.