等离子体气动激励控制超声速边界层分离的实验研究

等离子体气动激励与超声速气流相互作用已成为高速流动控制领域的研究热点。激波与边界层相互作用现象广泛存在于超声速飞行器之中。本文进行了等离子体气动激励控制压缩角区和激波诱导边界层分离的实验,通过流场纹影显示和壁面静压测量,研究等离子体气动激励如何影响激波、激波如何影响边界层特性的科学问题。实验结果表明:施加毫秒量级表面电弧放电能够前移压缩角区的诱导斜激波,使分离区后移,分离区域增加,但激波强度减弱,流场总压增加;施加微秒量级表面电弧放电能够抑制激波诱导边界层分离,使分离区减小,流场总压减小。基于实验结果,认为毫秒量级表面电弧放电激励控制超声速气流的主要机理为放电过程的焦耳热效应;微秒量级表面电弧放电激励控制超声速气流的主要机理为焦耳热效应和冲击波效应共同作用。

Experimental investigation on supersonic boundary layer separation control by plasma aerodynamic actuation

Plasma aerodynamic actuation and supersonic flow interaction has become the focus of researches. There is a wide range of universal phenomenon of shock wave and boundary layer interaction in supersonic aircraft. Experimental investigation on boundary layer separation induced by ramp and impinging shock wave are performing in supersonic flow by plasma aerodynamic actuation. Through schlieren imaging and wall static pressure results, plasma-shock wave interaction and shock-boundary layer interaction mechanism are studied. Experimental results show that the millisecond plasma actuation can make the shock wave induced by the ramp forward and enlarge the separation area. At the same time, the intensity of shock wave induced by the ramp is weakened. The main control mechanism are Joule heating effect. The microsecond plasma actuation can control the boundary layer separation induced by the impinging shock wave and reduce the separation area but the overall pressure reduced. The main control mechanism is Joule heating effect and impact effect based on experimental results.