Mathematical model and calculation of the unsteady combustion rate of the metallized solid rocket propellants

This paper provides a physical-mathematical model and the calculation results of unsteady combustion rate of a metallized solid fuel. The approach is based on the development of an adjoint mathematical model which takes into account the processes in solid and gas phases. On the fuel surface, the conservation of both energy fluxes and mass of the components is assumed. The equations of heat transfer and condensed phase decomposition are written for a computational domain. The double-rate and two-temperature model of the reacting flow of decomposition and gasification products is used over the solid fuel surface. The results of unsteady combustion rate calculated during the pressure drop are presented as functions of dispersion and mass fraction of the metal powder in a propellant composition. The obtained results are in a good agreement with the data available in scientific literature.