高超声速高焓边界层转捩的超声速模态  

Evolution of Supersonic Modes in Hypersonic High-Enthalpy Boundary Layer Transition

作　　者：赵洲源 陈贤亮 王亮[1] 符松[1] ZHAO Zhou-yuan;CHEN Xian-liang;WANG Liang;FU Song(Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学,北京100084

出　　处：《气体物理》2023年第3期35-45,共11页Physics of Gases

基　　金：国家重点研发计划(2019YFA0405200);国家自然科学基金(12072173);国家重大项目(GJXM92579);国家科技重大专项(2017-Ⅱ-0004-0016)。

摘　　要：随着飞行速域与空域的不断拓展,高超声速高焓边界层中的热化学非平衡(thermochemical non-equilibrium,TCNE)效应深刻影响了流动转捩过程。近年来,在第2模态下游区域出现的不稳定超声速模态引起了学者们的关注。超声速模态是指在边界层外缘处的相对Mach数大于1的模态,其传播速度快于远场的声波。采用线性抛物线稳定性方程(parabolized stability equations,PSE)理论研究了Mach数为20、半顶角为6°的尖楔绕流条件下超声速模态的临界壁温。研究发现,壁温越低,越容易出现不稳定的超声速模态。进而,探讨了平板边界层流动中不同Mach数条件下的超声速模态和扰动发展形式,发现Mach数增大,第2模态出现越早且最大增长率降低,N的峰值减小。在30 km的高空来流Mach数超过某个临界值时,扰动增长率和超声速模态的发展形式明显不同。With continuous expansion of flight speed and altitude domains,the high-temperature gas effects,especially the thermochemical non-equilibrium(TCNE)effects in hypersonic high-enthalpy boundary layers invalidated the calorically perfect gas(CPG)assumption.They can also largely influence the flow transition process.In recent years,the emergence of unstable supersonic modes in the downstream region of the second mode has been conerned.The so-called supersonic mode refers to the mode with a relative Mach number greater than one at the boundary layer edge,that is,a sound wave that propagates faster than that in the far field.Linear parabolized stability equations(PSE)theory was used to study the critical wall temperature of the supersonic mode under the condition of sharp wedge winding with Mach number 20 and half top angle of 6°.It is found that the lower the wall temperature,the more prone to unstable supersonic mode appeared.Furthermore,the supersonic mode situation and disturbance development form under different Mach number conditions in the flow of the plate boundary layer were explored.It is found that the Mach number continues to increase,the earlier the se-cond mode appears,the maximum growth rate of the second mode decreases,and the peak value of N decreases.At a speci-fic altitude of 30 km,when the Mach number exceeds a certain critical value,the disturbance growth rate and the development form of the supersonic mode are significantly different.

关 键 词：高超声速流动 高温气体效应 超声速模态 流动稳定性 边界层转捩 

分 类 号：O357.4[理学—流体力学]