Instability and Acoustics of the Supersonic Boundary Layer

Abstract

The questions on the interaction of a supersonic boundary layer with acoustic waves, which are considered in the present paper, were raised mainly in connection with the problem on the turbulence formation. At present the most complex problem on the prediction of the transition position in the boundary layer flows is related to the receptivity of these flows to the external effects. It appears that this problem was discussed in detail for the first time in [1], and during more than two subsequent decades many works were carried out on it. However, this problem has been studied more thoroughly both experimentally and theoretically for the subsonic flows. A review of the early works of the influence acoustic field effect on the transition from a laminar supersonic boundary layer to the turbulent has been given in [2]. The problems on the supersonic flow aeroacoustics were studied mainly within the framework of the investigations on the conditions for the onset of auto-oscillations and sound generation by the supersonic shear flows in the jets and mixing layers [3, 4]. The advanced approach based on the idea of the possibility of the mutual influence of the acoustic and hydrodynamic waves has been demonstrated in [5]. A relation between the acoustics problems and stability was shown thereby, to which an attention was drawn also in [10].