Stability of supersonic boundary layer under the influence of heavy gas injection: experimental study

Experiments were performed on the influence of distributed injection of a heavy gas (elegas SF 6 ) into the near-wall region of the supersonic (freestream Mach number М ∞ = 2) boundary layer on its stability in relation to natural disturbances. Heavy gas injection for the case of linear development of disturbance field results in boundary layer stabilization. It was experimentally proved that the elegas injection can suppress disturbances at the frequencies higher than 15 kHz for the tested range of the streamwise coordinate.