Research on the effect of microslits-micro blowing/suction on the flow stability of a hypersonic boundary layer

Blowing and suction at the wall could affect the stabilization of a hypersonic boundary layer and change the transition onsets. The present study considers the microslits as the blowing/suction medium, introduced porosity into the the normal velocity, and combined with the acoustic admittance as a coupled model that accounts for the blowing/suction and its medium effect. The coupled model is verified by direct numerical simulation (DNS) by comparing with the results calculated by blowing/suction from the bottom of real microstructure. Based on this model, the coupling stabilization effect of microslits and blowing/suction on the hypersonic boundary layer is investigated by emphasizing the locations of the blowing/suction strip using linear stability theory (LST) and DNS. Results reveal that compared with the sole effect of the microslits, the additional blowing destabilized the disturbances, and otherwise, the additional suction suppressed the growth of perturbations.