Fig. 4From: Broadband design of acoustic metasurfaces for the stabilization of a Mach 4 boundary layer flowEffects of the admittance phase and amplitude of the acoustic metasurface on the growth rates of unstable modes (|A| = 0 corresponds to the smooth wall). (a) phase θ = 0.5π. (b) phase θ = 0.75π. (c) phase θ = πBack to article page