固液混合火箭发动机仿真与优化设计

Simulation and optimization design of hybrid rocket motor

建立了固液混合火箭发动机的仿真模型和相应的单目标和多目标优化模型,编制了系统仿真程序;采用差分进化算法针对不同的优化目标对发动机的参数进行优化;针对挤压式系统建立了质量模型,在优化过程中考虑了主要部件结构质量对发动机性能的影响;针对固液发动机常用的侧面燃烧药柱编制了内弹道计算程序。以药柱几何参数、氧化剂流量、燃烧室平均工作压强和喷管扩张比等参数为设计变量,对发动机平均比冲、总质量、关机时飞行速度和密度比冲等性能参数进行优化,在Pareto分析的基础上选择了氧化剂流量、燃烧室平均工作压强和喷管扩张比对发动机性能的影响作了深入研究;最后对某型固液发动机进行了优化分析。

The simulation model and the relevant multi-objective optimization model were established for hybrid rocket motor.A system simulation procedure was programmed.Design parameters of the system were optimized owing to different optimization objectives based on differential evolution algorithm.Weight model of gasbag pressurized system was established.Main components weights were concerned in optimization because of their influence on system performance.An interior ballistics procedure was programmed for side burning grain applied in hybrid rocket motor.The optimization design variables were geometrical parameters of grain,oxidizer flux,combustor averaged pressure and expansion ratio of nozzle.The optimization objectives were averaged specific impulse,weight,density specific impulse and flight speed at shutting down.The effects of oxidizer flux,combustion chamber averaged pressure and expansion ratio on motor performance were analyzed based on DOE and pareto analysis.At last,a hybrid rocket motor was optimized and analyzed.