三角翼前缘周期性质量引射对前缘脱体涡的影响

Influence of the Periodic Mass Injection at the Leading Edge of Delta Wing on the Leading-edge Vortex Breakdown

本文论述了采用周期性质量引射作为激振的手段，在三角翼的前缘施以较弱的次谐波扰动，从而延缓旋涡破碎．研究结果表明：在很小的引射动量系数（Ｃμ＝０．００２）及低频引射（ｆｊ＜２Ｈｚ）条件下，沿前缘的周期性质量引射会显著地推迟脱体涡的破裂．在本文条件下最佳激励频率为未受激励的前缘离散脱落涡频率的四分之一．在最佳激励频率下，破裂点后移的幅度可达２０％弦长．

This paper deals with the mathod of excitaion using periodic mass injection. A weak subharmonic perturbation is applied at the edge of the wings to delay the vortex breakdown. It is observed that when the injection momentum coefficience is small(Cμ≈0. 002) and the Perturbation frequency is low(fj<2Hz), the Perturbations at the leading-edge has a significant influence on the leading-edge vorex breakdown. There is an optimum Perturbation frequency, which is 1/4 of the natural shedding frequency of the haling-edse discrete vortices. And on optimum perturbation frequency, the breakdown point delays by 20% of wins root chord lenth.