装 药 及 喷 管 型 面 对 固 体 发 动 机 涡 声 振 荡 影 响

To study the cause of internal pressure oscillation of a Solid Rocket Motor(SRM)with the finocyl grain,we calculate the flow field with large eddy simulation and other methods,capture the pressure oscillation frequency and the vortex shedding frequency,and analyze the effects of burning surfaces at different times,different nozzle convergence sections and different dump structures on the vortex-acoustic coupling. The results show that the finocyl grain is more prone to vortex-acoustic oscillation in the early stage of the grain burnback,while the flow field is relatively stable at the end of combustion. By adjusting the convergence section surface of the nozzle,the pressure oscillation can be weakened to a certain extent. However,the vortex-acoustic frequency cannot be broken. By changing the dump structure,the vortex-acoustic coupling phenomenon can be effectively eliminated,so as to inhibit the unstable combustion of combustion chambers of solid rocket motors.