The problem of boundary layer receptivity on concave walls to surface non-uniformities causing excitation of the instable Goertler vortices was experimentally investigated. Experiments were carried out using the method of controlled unsteady perturbations for non-uniformities of waves with 8 and 12 mm width in a frequency range between 2 and 14 Hz. The linear receptivity coefficients independent of the specific shape of the non-uniformities are obtained and can be used for verification of various theories. Magnitudes of the coefficients are relatively low. They increase along the frequency of surface vibrations, and at high frequencies they depend on the lateral dimensions of the non-uniformities. The phases of coefficients also raise with the frequency. It is shown that in real life conditions the presence of unsteady Goertler vortices can be significant due to greater receptivity of the boundary layer to high-frequency surface vibrations.
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