Optimization design of anti-creep reinforcement structure for solid rocket motor propellant grain

To address the creep issue that arises during the long-term vertical storage of solid rocket motor (SRM), a method was proposed that involved embedding a specially shaped functional combustible core model (reinforcement structure)into the propellant grain matrix without altering the basic structure of the grain. Initially, the distribution patterns of creep in the propellant grain under the coupled effect of solidification cooling and vertical self-weight were analyzed by using three-dimensional numerical simulation methods. Subsequently, the reinforcement structure was designed by using the solid isotropic material with penalization (SIMP) method for topology optimization, determining the geometric configuration of the embedded reinforcement structure. Finally, the final optimized design results were determined through comparative analysis of the anti-creep effect of the topology-optimized reinforcement structure. The research results demonstrate that the deformation stress and strain of the solid rocket motor propellant grain with the reinforcement structure are significantly reduced compared to those without the reinforcement structure, effectively suppressing the creep of the grain.