Experimental study on the hypersonic double incident shock wave/boundary layer interaction regulated by plasma actuation array

In the inlet passage of a hypersonic vehicle, multi-channel shock waves inevitably interact with the boundary layer, producing complex multi-channel shock wave/boundary layer interactions (SWBLIs). The flow separation caused by these interactions significantly decreases the intake efficiency and may prevent the intake from starting. The typical interaction mode of multi-channel interactions is through double incident SWBLIs. Therefore, it is necessary to study the characteristics of double incident SWBLIs and identify relevant flow control techniques. In this paper, the characteristics of hypersonic double incident SWBLIs are first examined, and then the results of an experimental study on regulation using a plasma actuation array are reported. We find that plasma actuation can positively regulate the hypersonic double incident SWBLI, and the optimal control effect reduces the area of the separation bubble by 38.62%. The main regulation mechanism involves suppressing the low-frequency instability of SWBLIs through a high-frequency shock effect. The regional scale of the separation bubble can be controlled by regulating the shock wave oscillation range. Correlative results provide technical and method support for the application of plasma actuation in hypersonic double incident SWBLI regulation and present a new idea for the selection of flow control methods for advanced intake systems.