Combustion of solid propellant with micron-sized Aluminium under the acceleration force

Abstract

The paper presents a physical-mathematical model for metallized solid propellant combustion under acceleration directed along the normal to the burning surface. The model takes into account the thermal effect of decomposition of the condensed phase, convection, diffusion, the exothermic chemical reaction in the gas phase, heating and combustion of Al particles in the gas flow, the flow of combustion products, the particle velocity lag relative to the gas and the field effect of acceleration on the motion of Al particles. The effect of the Al particle size and mass fraction, emitted from the burning surface, on the burning rate is also taken into consideration. The impact of the Al particle size, emitted from the burning surface, on the linear burning rate has been investigated under acceleration. The study results showed that with increasing acceleration the burning rate increased. It was also revealed that the larger was the size of aluminum particles emitted from the burning surface, the higher was the response of the burning rate to acceleration. The results showed that increasing the mass fraction of aluminum in the propellant composition led to an increase in the response of the relative burning rate. It was also found that the relative burning rate sensitivity increased with pressure above the burning surface. The results obtained are in a qualitative agreement with those described in the scientific literature.