Numerical simulation of particle erosion in the internal flow field of solid rocket motor nozzle using Rocstar

Solid composite propellants often contain metal particles, such as aluminum particles, and the internal flow field in a solid rocket motor is a typical gas–solid two-phase flow field. In this study, to address the problem of the erosion of particles on the wall during the working process of an engine, a particle erosion model was established based on the interaction mechanism between the particles and the wall. From the perspective of particle dynamics, the interaction mechanism between the moving particles and the wall was analyzed. The force of the particles on the wall surface was obtained, and a formula for solving the particle erosion rate was deduced by using the strength theory and the energy conservation principle. It was combined with Hertz’s contact theory to analyze the factors influencing the erosion rate. In this paper, the particle erosion experiments revealed not only the relationship between erosion rate and erosion angle but also the correlativity between erosion rate and particle concentration. In addition, the experimental results are consistent with the deduced results, which proves the reliability of the model established in this paper. The multiphysics simulation program Rocstar, developed by the Center for Simulation of Advanced Rockets at the University of Illinois, was used to perform a numerical simulation of the two-phase flow in the Jet Propulsion Laboratory nozzle. The results agreed well with the literature and the experimental data. The feasibility and accuracy of the calculation of the gas-phase and two-phase flow fields of the solid rocket motor nozzle were confirmed, laying the foundation for the numerical simulation of the entire process of the full flow field of the engine.