Numerical Investigations on Tollmien–Schlichting Wave Attenuation Using Plasma-Actuator Vortex Generators

摘要

Recently, plasma actuators have been employed to control laminar-to-turbulent transition in Blasius flow by exciting counter-rotating longitudinal vortices. Due to the resulting momentum redistribution, the vortices generate a spanwise modulation of the flow with regions of high and low streamwise velocity, which are commonly denoted as streaks. In the case of moderate amplitudes, the streaks yield a stabilization of the flow by reducing the amplification of Tollmien-Schlichting waves, and hence delayed transition. In the present work, two fundamentally different actuator setups are investigated: a symmetrical one, exciting counter-rotating vortices; and a nonsymmetrical one, exciting corotating vortices. The differences between these setups are discussed in detail, and the respective stabilization of the flow is scrutinized.