Secondary instability control of compressible flow by suction for a swept wing

The crossflow instability of a three-dimensional boundary layer is a main factor affecting the transition around the swept-wing. The three-dimensional boundary layer flow affected by the saturated crossflow vortex is very sensitive to the high frequency disturbances, which foreshadows that the swept wing flow transition will happen. The primary instability of the compressible flow over a swept wing is investigated with nonlinear parabolized stability equations (NPSE). The Floquet theory is then applied to the analysis of the influence of localized steady suction on the secondary instability of crossflow vortex. The results show that suction can significantly suppress the growth of the crossflow mode as well as the secondary instability modes.