The numerical procedure for a diffusion flame based on Ammonium Perchlorate/Hydroxyl-Terminated Polybutadiene (AP/HTPB) composite propellant in a solid rocket motor (SRM) is presented. This article accounts for the turbulence effects in a combustion chamber with sidewall mass injection and the propellant diffusion flames at various axial locations are studied. The mutual coupling between the vortical and entropy modes is discussed comprehensively, with the inclusion of the influence of the chamber pressure. The effects of the AP particle size and the combustion environment are also analyzed. The flow evolution in the SRM is clearly observed in the results: laminar, transitional, and turbulent. Compared with the laminar area, the flames fluctuate drastically in the turbulent flow, and the chemical kinetics processes are altered greatly. The diffusion and mixing processes of the reactants are enhanced due to the contribution of the turbulence, and the heat release of the flames is elevated. The high chamber pressure and smaller AP size could lead to more intensive fluctuations of the flame heat release. This may drive thermoacoustic instability in the SRM.

提出了在固体火箭发动机（SRM）中基于高氯酸铵/羟基末端聚丁二烯（AP / HTPB）复合推进剂的扩散火焰的数值程序。本文解释了在燃烧室中进行侧壁质量喷射时的湍流效应，并研究了在不同轴向位置的推进剂扩散火焰。讨论了涡旋和熵模之间的相互耦合，包括了腔室压力的影响。还分析了AP粒径和燃烧环境的影响。结果中清楚地观察到了SRM中的流动演化：层流，过渡和湍流。与层流区域相比，火焰在湍流中剧烈波动，化学动力学过程发生了很大变化。由于湍流的作用，反应物的扩散和混合过程得以增强，并且火焰的热释放得以提高。较高的燃烧室压力和较小的AP尺寸可能导致火焰热量释放的剧烈波动。这可能会导致SRM中的热声不稳定。