Propagation of stationary and traveling waves in a leading-edge boundary layer of a swept wing

The transition characteristics around the leading edge of a swept-back wing shape were numerically investigated. We conducted direct numerical simulations (DNSs) swept-wing with high Reynolds number Re=Rec/cos ?=5.85×106 based on chord length sweep angle ?=70°. In study, randomly distributed impulsive local body force was applied at wall to encourage transition. Through forcing, two coherent waves formed in both an attachment line and three-dimensional boundary layer: A stationary elongated streak structure external flow direction traveling wave direction. These slightly different from those layer. computed nonmodal transient energy growth for present leading-edge layer compared observed DNSs. modes DNSs are found be group; these temporally grow maximum short target time ( ?<0.02). One our conclusions is that occurring strongly related short-term phenomena nonorthogonality field. When roughness forcing gradually increased, not generated, whereas was. This considered because attachment-line receptive small disturbance more likely generate than wave.