类X-43A飞行器高超声速分离仿真

Hypersonic separation simulation of aerocraft similar to X-43A

高超声速飞行器级间分离过程广泛存在于军事和航空航天应用中。为了对该过程中气动干扰和各分离参数的影响有更加深入认识,以类X-43A飞行器为研究对象,采用网格变形/局部网格重构的方法对其进行仿真研究。详细分析了高超分离过程中典型的流场结构,尤其是飞行器和助推器之间的级间干扰;另外,重点讨论了初始攻角、弹射力对分离过程中飞行器和助推器的轴向/法向相对距离、气动力以及飞行器攻角的影响规律。结果表明:级间分离过程受到涡流和激波的双重干扰;攻角对飞行器和助推器法向相对距离影响较大,小攻角或负攻角更有助于二者分离;弹射力对轴向相对距离影响显著,较大的弹射力能够使飞行器较快脱离级间干扰区,达到安全的分离距离。

Stage separation process widely exists in the military and aerospace applications of hypersonic aerocraft.To further understand the aerodynamic interference and parameter effects in the process,an aerocraft similar to X-43 A is chosen as the research object,and the simulation method of mesh deformation/local grid reconstruction adopted.The typical flow field structure,particularly the interstage interference between the aerocraft and the assistor,during the separation process is analysed.Additionally,the influences of the initial angle of attack and ejection force on the axial and normal relative distance,aerodynamic force and the angle of attack during the separation process are emphatically discussed.The results show that the interstage separation process is disturbed by the vortex and shock waves.The angle of attack has a large effect on the relative distance between the aerocraft and the assistor,and a small or negative angle of attack is more helpful for the safe separation.The ejection force has a significant influence on the axial relative distance,and a larger ejection force enables faster separation of the aerocraft from the interstage interference zone to reach a safe separation distance.