Modeling of Aluminum Particle Combustion in Solid Rocket Combustion Chambers

Abstract

Two phase ow is a challenging subject in the design of solid rocket motors. Not only does it impact the motor performance characteristics, but also inuences the thermal and chemical loads on the motor components. The main particulate found in hybrid and solid rocket combustion is made of aluminum. This study focuses on the continuous development of the TAU Lagrangian particle tracer, including eorts in modeling droplet evaporation, droplet breakup and condensation processes to describe the behavior of the solid particles within the combustion chamber. By combining computationally aordable models, an engineering model able to predict thermal, chemical and mechanical loads is presented. Application to a solid rocket motor engine indicates that this particular modeling approach underpredicts the combustion chamber temperature. Implementation of nucleation and subsequent condensation as a gas phase reaction resulted in chamber temperatures close to the temperature found from equilibrium combustion. While the temperature and species distribution within the chamber largely depend on the modeling of the combustion process, it is shown that the droplet breakup model has a much stronger inuence on the accurate prediction of droplet diameters in the nozzle and subsequent plume.