Two-zone model for combustion of a composite solid propellant with a coolant

A mathematical model for combustion of a propellant with a coolant taking into account the two-zone structure of the combustion front due to condensed- and gas-phase reactions was developed and examined. Formulas for the burning rate, reaction-zone temperature, and burning-rate sensitivity to internal and external parameters of the system were derived in analytical form. The burning rate was examined numerically as a function of pressure, the characteristic size of the system, component content, and thermodynamic and kinetic parameters. Recommendations are given on methods of obtaining particular ballistic properties by varying the initial parameters of the system.