Abstract
In order to investigate the fluid-dynamic effect of a deformable actuator to be used in practical turbulence control, direct numerical simulation of associated laminar flow is carried out. It is shown that the actuator induces much larger wall-normal and spanwise velocities compared to an equivalent local blowing actuator. The streamwise vorticity induced at the wall is proportional to both surface velocity and displacement, whilst the spanwise and wall-normal vorticities are independent of the surface velocity. Induced vorticities are more than 10 times larger than the rms values in turbulent flow, in spite the surface velocity is on the order of 1/100 of the centerline velocity. These results suggest a possibility of effective turbulence control through the manipulation of vortex sheets in the viscous sublayer.
