Plate boundary layer transition regulation based on plasma actuation array at Mach 6

An experimental study on controlling hypersonic boundary layer transition using a surface arc plasma actuation array was conducted. First, base boundary transition characteristics were analyzed in virtue of various sensors and high-speed schlieren, and the transition criterion was established based on the critical value of schlieren spatial power spectral density resolution. Then, the influence of three different actuation frequencies (8, 34, and 55 kHz) was studied based on linear stability theory analysis. The impact of different actuation frequencies on the dominant unstable waves in the boundary layer was analyzed, and a transition criterion under the regulation of plasma actuation was proposed. Finally, the proper orthogonal decomposition method was used to analyze the influence of different actuation frequencies on the unstable characteristic structures. Based on the research, the efficacy of plasma actuation array in promoting transition is verified, the corresponding regulation mechanism is summarized, and transition regulation mechanization is refined.