Mean lift generation on cylinders induced with plasma actuators

Abstract

Bluff body flow control based on plasma actuators requires suitable strategies to attain the desired objectives. The strategy selection becomes more critical in situations where the free airstream velocity is much higher than the maximum velocity that can be produced by the flow control device. In this work, we report recent efforts to produce on a circular cylinder forces in direction transverse to the free flow. Free stream velocities considered in this work are as high as 45 m/s ((Re(O) 1 × 105), which result much higher values than the maximum velocities (about 5 m/s) usually induced by the kind of plasma actuator here considered (dielectric barrier type). Our strategy consisted on promoting asymmetries on boundary layer separation with a four electrode arrangement. In our experiments, we measured drag and lift forces and explored the effect of exciting the flow with steady and non-steady actuations. The device demonstrated authority to induce significant transverse forces and optimal frequencies resulted in all cases close to the vortex shedding frequency.