Boundary layer bypass transition

Starting from a Blasius flat-plate boundary layer, there are several approaches of promoting the downstream flow to bypass transition to turbulence: blowing and suction at the wall, passing wakes, trip wire, roughness element, oblique waves, body forces, to name a few.We define bypass transition in the narrow sense as a superposition of the Blasius layer with freestream continuous isotropic turbulence at an initial intensity level (FST) between approximately 1% and 4%.Previous studies 1 have stipulated that bypass transition develops its own primary instability in the form of long-streaks whose algebraic/transient growth leads to secondary instability (streak meandering or a) E-mail: Xiaohua.