On the Receptivity Process of Supersonic Laminar Boundary Layer

摘要

The receptivity of supersonic boundary layer is examined numerically at a freestream Mach number M_1 = 2.2. The external disturbance is introduced by forcing weak sinusoidal u-fluctuation on a narrow strip of the wall. The result shows that the intensity of excited T-S wave is proportional to that of T-S wave number spectrum contained in the external disturbance. The receptivity to time periodic Mach waves incident onto leading-edge is also examined. When the Mach wave is coming from below the plate, the excited flow is found to be governed by the T-S wave in the upper side boundary layer, and by the forced wave in the lower side boundary layer.