SPATIAL SIMULATIONS OF OBLIQUE TRANSITION IN A BOUNDARY-LAYER

Simulations of oblique transition in the spatial domain are presented, covering the complete transition process into the turbulent regime. I t is conjectured that the three stages identified here and elsewhere a re universal for oblique transition in all shear flows: first a nonlin ear generation of a streamwise vortex by the oblique waves, second a t ransient growth of streaks from the vortex by the lift-up effect, and third a breakdown of the streaks due to secondary instability.