Combustion of a double-base homogeneous propellant in a rocket motor

A comprehensive numerical analysis has been conducted to study the combustion of a double-base homogeneous propellant in a rocket motor. Emphasis is placed on motor internal flow development and its influence on propellant combustion. The formulation is based on the complete conservation equations of mass, momentum, energy, and species concentration, with consideration of finite-rate chemical reactions and variable properties. Turbulence closure is achieved using a two-layer model that takes into account the wall-injection effect arising from propellant burning. The governing equations and associated boundary conditions are numerically solved by means of a fully coupled implicit scheme capable of treating chemical reacting flows over a wide range of Mach number. Various aspects of the internal flowfield and combustion wave structure in a rocket motor environment are investigated systematically. The effects of pressure and cross flow on propellant burning rate are also studied. Results indicate that, for double-base propellants, no specific interactions between turbulence and combustion are observed. The propellant combustion can be locally modeled as a well-stirred reactor, and the influence of turbulence appears mainly in the calculation of eddy diffusivities.