基于详细化学反应机理对微小型化学推进器进行了零维的瞬态数值模拟.推进器的燃烧室采用良搅拌反应器模型,燃烧室后的喷管采用稳态准一维等熵流理论.着重研究了微小型化学推进器的微尺度特性和启动特性,讨论了引入多孔介质后对系统工作性能的影响.微小型化学推进器的最佳燃气流率范围随系统特征尺寸的减小而变窄;稳态推力、启动性能都优于相同条件下的冷态推进器;引入多孔介质可以提高燃烧稳定性,改善脉冲推进的再点火能力,拓宽高比冲设计工况的燃气流率范围.
A zero-dimensional modeling of the operation cycle of a micro/mini-chemical propulsion system was performed based on the comprehensive detailed chemical reaction mechanism. A perfectly stirred reactor model was adopted for its combustion chamber, and the steady quasi-lD isentropic flow was used for the nozzle flow. The micro-scale effects, the startup characteristics and the influence of porous media on the propulsion performance were discussed. The optimum range of mass flow rates decreases with the thruster size; the characteristic propulsion parameters like thrust and startup-interval are superior to frozen-flow thrusters; combustion stability and the ability of pulse re-ignition can be enhanced by introducing porous media into the combustion chamber, and the optimum range of mass flow rates can also be extended.