基于地外天体起飞的真空羽流导流技术仿真与试验研究

针对着航天器发动机羽流导流问题,基于工程经验提出了四种典型导流装置型面(包含内凹槽形式和导流锥形式等),利用计算流体动力学/直接模拟蒙特卡罗(CFD/DSMC)耦合方法,对起飞过程中羽流导流带来的气动力和气动热效应进行了数值模拟,并对不同导流装置情况下羽流场激波、航天器表面压强和热流密度分布规律进行了分析,给出了四种导流装置的导流效果评价。最后以导流锥形式开展试验,对仿真算法进行了验证。结果表明：羽流导流并没有导致发动机燃烧不稳定;综合考虑航天器羽流和发动机安全性,大导流锥导流的方案最优;在导流锥附近的激波位置及形态和仿真一致,仿真与试验的变化趋势一致,仿真算法可信,数据规律可以作为工程参考。

Research on simulation and test of vacuum plume diversion technique based on vehicles taking off outside the earth

In view of the problem of limitations on engine plume diversion, based on engineering experiences, four typical molding surfaces of diversion devices (including form of inner groove and form of diversion cone) were proposed to carry out numerical simulation of the aerodynamic and aerothermal effects caused by plume diversion during take-off using the coupling simulation method of computational fluid dynamics (CFD) and direct simulation of Monte Carlo (DSMC), and analyze the plume field shock wave and spacecraft surface pressure and heat flow density distribution law, thereupon the evaluation on diversion effects of the four diversion devices was presented, and finally tests in the form of diversion core were conducted to verify the simulation algorithm. The result show that the engine is stable with the plume diversion, the scheme of the large diversion core is optimal considering the spacecraft plume and engine safety, the shock near the diversion core is the same as the simulation, the variation trend of simulation and test is consistent, the algorithm is credible and the law can be applied in engineering.