Metal shield influence on underwater ignition of a dibasic solid propellant with a spiral heated by a capacitor

The earlier developed model of underwater ignition of the dibasic solid propellant (DSP) by a spiral filament is generalized for an open gas generator in which there is no surface armor protection and burning zone localization is provided by means of a heat-resistant glass that is considered under a model boundary condition by means of an additional “negative source”. The calculations were based on the adiabatic method. The presence of a heat-resistant glass on the end face essentially affects the ignition delay time. The spiral filament is heated during the discharge of the capacitor.
To enable the required ignition process, the energy sources should produce an energy density of more than $30$ MJ/m$^2$ at the DSP heating area.