Control of separated ows with plasma actuators

J. D'ADAMO; R SOSA; G ARTANA

Congreso; XII Reunión sobre recientes avances en física de fluidos y sus aplicaciones; 2012

Active control over a backward-facing step separated ow is studied experimentally by means of plasma based devices. The Reynolds num- ber based on the step height H is about 1500. Electrohydrodynamic actuators, dielectric barrier discharge(DBD) type, are ush-mounted to the step wall. The DBD conguration add momentum locally, nor- mal to the separated shear layer thus producing strong modications downstream. The actuation is periodic and its frequency and ampli- tude are scrutinized to characterize the ow behavior under forcing. Measures of velocity elds for these ows are obtained from particle image velocimetry (PIV). As reported by previous works, the reat- tachment length shows an important reduction for an optimum forcing frequency. This value closely matches the shear layer ow natural fre- quency. On the other hand, the ow is less sensitive to the forcing amplitude though the analysis allows us to optimize the actuation in order to save power consumption.