发动机喷流对火箭气动特性影响

开展了考虑底部发动机喷流影响的火箭气动特性CFD仿真设计，比较了有/无喷流时火箭附近流场结构、表面压力分布、整体气动力/力矩特性在亚/超声速段的差异，结果显示，发动机喷流对火箭亚声速段的轴向力、法向力和俯仰力矩特性均有较为显著的影响，且有减小尾部空气舵气动控制力矩的影响，而超声速段的影响仅限于轴向力。该仿真结果与飞行试验气动辨识结果较为一致。基于仿真分析结果，可建立一种折中考虑喷流影响的气动特性设计方法，供火箭精细化气动特性设计参考使用。 

Effect of Engine Jets on Rocket Aerodynamic Characteristics

In this paper, the CFD simulation of rocket aerodynamic characteristics considering the influence of bottom engine jet was carried out. The differences in flow field structure, surface pressure distribution and overall aerodynamic force and moment characteristics of the rocket at subsonic and supersonic speeds with or without jet flow were compared. The simulation results show that the jet flow has a significant influence on the axial force, normal force and pitching moment of the rocket at subsonic speed, and it can also reduce aerodynamic control moment of the tail rudder. The jet flow only affects the axial force when the rocket is at supersonic speed. The simulation results are consistent with the aerodynamic identification results of flight test. Based on the simulation results, a compromise aerodynamic characteristics design method considering the influence of engine jet can be established, which can be used as a reference for the fine aerodynamic design of rockets.