Research on the combustion mechanism of boron-based fuel-rich propellant under low pressure

Temperature distribution of combustion wave and the quench combustion experiments were carried out for two boron-based fuel-rich propellants under low pressure, and the quenched surfaces of the propellants were analyzed with SEM and EDS. The results showed that coating boron with AP could increase the combustion temperature, pressure exponent and combustion intensity, while made the combustion process become more complicated. A "deposit" layer was found to be formed when the boron-based fuel-rich propellant burned under low pressure, and the combustion process of the propellant could be divided into two reaction zones, one of which was condensed reaction zone on and near the combustion surface, and the other was gaseous reaction zone in the pores of the inert "deposit". Considering the formation of "deposit", a combustion model was established based on BDP combustion model, and the combustion characteristics of boron-based fuel-rich propellant under low pressure could be interpreted well by the model.