高速升力体非对称流向涡不稳定性研究  

Study on the linear instability of asymmetric streamwise vortices over a high-speed lifting body

作　　者：张彬 李晓虎 涂国华 陈坚强 ZHANG Bin;LI Xiaohu;TU Guohua;CHEN Jianqiang(State Key Laboratory of Aerodynamics,Mianyang621000,China)

机构地区：[1]空天飞行空气动力科学与技术全国重点实验室,绵阳621000

出　　处：《空气动力学学报》2025年第2期75-85,I0002,共12页Acta Aerodynamica Sinica

基　　金：国家自然科学基金(92052301)。

摘　　要：高速飞行器实际飞行时存在非对称流动,为加深对非对称三维流场结构失稳机制的认识,采用二维全局稳定性分析方法对高速转捩研究飞行器(HyTRV)腰部非对称流向涡结构的稳定性特征进行了研究。模型长度为1600 mm,攻角为0º,来流马赫数为6,单位雷诺数为1.0×10^(7)/m,静温为79 K。采用等温壁面(300 K)条件,通过高阶精度有限差分方法直接求解N-S方程获得层流基本流场。计算结果表明:升力体上表面顶部及下表面长轴处的低速流体向腰部汇聚,形成非对称流向涡,其中靠近下表面一侧的涡卷曲程度更强。稳定性分析结果表明,升力体腰部非对称流向涡的不稳定模态主要有内模态、外模态和Mack模态,内模态主要由展向速度剪切主导,外模态主要由法向速度剪切主导。不同于传统对称流向涡的是,非对称流向涡的扰动形函数主要分布在流向涡卷曲更强的一侧。基于全局稳定性分析的e^(N)方法求解不稳定模态的N值发现:上游Mack模态N值较大,可能在噪声环境下引起转捩;下游外模态N值较大,可能在静声环境下引起转捩。The two-dimensional global stability analysis method(BiGlobal)was employed to investigate the instability characteristics of asymmetric streamwise vortex structures at the waist of a hypersonic transition research vehicle(HyTRV),with parameters set as model length 1600 mm,0°angle of attack,freestream Mach number 6,unit Reynolds number 1.0×10^(7)/m,and static temperature 79 K.The laminar base flow field was obtained through direct numerical simulation by a high-order finite difference method under an isothermal wall condition(300 K).The results indicate that low-velocity fluids near the top of the upper surface and along the long axis of the lower surface converge at the waist,forming streamwise vortices.The pressure gradient disparity between the two sides leads to asymmetric development of these vortices,with the one on the lower side exhibiting more pronounced curling.Stability analysis reveals that the unstable modes of asymmetric streamwise vortices at the lifting body's waist can be categorized into inner modes,outer modes,and Mack modes,aligning with previous research findings.The inner modes are primarily influenced by spanwise velocity shear,whereas the outer modes are predominantly affected by normal velocity shear.The disturbance shape functions are primarily distributed on the side where the streamwise vortex exhibits stronger curling,which is different from the traditional symmetrical streamwise vortex.Utilizing the e^(N)method based on global stability analysis,it is concluded that the N factor of the Mack mode is higher in the upstream region.This suggests that the Mack mode is more likely to initiate transition in a noisy environment.Conversely,the N factor of the outer mode is more pronounced in the downstream region,indicating a higher potential for transition in a quiet environment.

关 键 词：HyTRV 升力体 全局稳定性分析 非对称流向涡 e^(N) 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程] O355[理学—流体力学]