Stability of Supersonic Swept-Wing Boundary Layers with or without Crossflow

Abstract

We examine the stability of three-dimensional supersonic boundary layers over an infinite swept wing made from the semispan model of the NAL supersonic experimental airplane. The original wing was designed so as to suppress both streamwise and crossflow instabilities under cruise conditions. It is confirmed through linear stability analyses of the full boundary layer and the boundary layer without crossflow that the spatial growth of first-mode waves in the full boundary layer is mainly due to streamwise instability and restrained near the design angle of attack.