Direct Numerical Simulation of a Swept-Wing Boundary Layer with an Array of Discrete Roughness Elements

Direct numerical simulations of crossflow-induced boundary layer transition are performed for a 45-degree swept wing with an array of discrete roughness elements placed near the leading edge, at a chord Reynolds number of 2 4 million A large part of the wing upper surface in the chordwise direction (hut with only less than two-percent chord in the spanwise direction) is resolved to simulate the growth and breakdown of crossflow vortices on the wing The procedures. initial results and some difficulties encountered during the study are described