The combustion of solid monopropellants and composite propellants

TLDR: In this article, a model describing the combustion of composite propellants has been applied to three different types of composite powders, and to two oxidizers which burn as monopropellants.

Abstract: A model describing the combustion of composite propellants has been applied to three different types of composite propellants, and to two oxidizers which burn as monopropellants. The oxidizers studied are AP, HMX, and KP (ammonium perchlorate, cyclotetramethylenetetranitramine, and potassium perchlorate), each of which has unique combustion characteristics. The monopropellant combustion of AP and HMX has been considered in detail, particularly that of AP. Calculations have been compared with experimental data for the burning rate, the sensitivity of the burning rate to both pressure and initial temperature, and the surface temperature. The agreement between the calculations and experimental data is very adequate. The results indicate that AP and HMX apparently burn with a considerable exothermic reaction at the burning surface as well as in the gas phase above the surface. Both reactions must be accounted for to give consistent results. The combustion of the three oxidizers burning with a fuel in composite propellants has also been simulated. Experimental data are presented for propellants in which the oxidizer has been systematically varied. A direct comparison has been made between the data and the calculations of the model. The calculations agree quite well with the combustion characteristics of the three different types of composite propellants.