数值研究平板方舵激波-湍流边界层干扰

数值研究了平板方舵激波-湍流边界层干扰流场。模拟出了分离激波与弓型激波砬撞后形成的“λ”激波结构;消晰地显示了分离区中的旋涡结构,发现流场中会出现二次分离涡,并从理论上分析了流场对称面涡心形态与非定常的关系,得到了涡心为不稳定螺旋点或出现极限环是非定常流动特征的新结论。

NUMERICAL STUDY OF SHOCK WAVE AND TURBULENT BOUNDARY LAYER INTERACTION INDUCED BY FLAT-FACED BLUNT FIN

The shock wave and turbulent boundary layer interaction induced by flat-faced blunt fin mounted on a flat plate is numerically studied. The calculation results display "A" shock wave structure generated by the impingement of separated shock with the bow shock. Some new phenomena are discovered in this flow through the simulation, such as the bifurcation and mergence of vortices in the separation region ahead of blunt fin, the existence of secondary separation and secondary vortex, multiple vortices structure and so on. By theoretical analysing, we obtain a new conclusion that if the center of vortex is an unstable spiral point or limiting circle exists near the vortex center, the flow field is unsteady.