Numerical Simulation of Three-dimensional Combustion Flows of Pasty Propellant Rocket Motor

Pasty propellant rocket motor (PPRM) is considered to be one of the promising advanced chemical propulsion technologies due to the advantages of flexible thrust adjustment and multi-pulse operation. To reveal the underlying characteristics of internal combustion flows of pasty propellant rocket motor, a three-dimensional CFD simulation is established, considering the grain pyrolysis process, gas-solid coupled heat transfer as well as complex chemical kinetics and verified by comparing with experiment data. The results show that the flow in the combustion chamber of PPRMs presents strong three-dimensional characteristics, and the combustion process takes place in the extremely thin layer adjacent to the surface of propellant grain. Furthermore, with the increase of flow rate by 3 times, the thrust of the combustion chamber increases by 3.32 times, indicating the effectiveness of variable thrust adjustment of pasty rocket engine. The simulation accurately captures the combustion and flow characteristics, which provides guidance for the subsequent design optimization of the pasty propellant rocket motor.