Lift Enhancement of a Pitching Airfoil in Dynamic Stall by DBD Plasma Actuators

Control of Dynamically Stalled Flowfield around a Pitching Airfoil by DBD Plasma Actuator

“…11 The conclusion is that the necessary computational domain length is the same as the chord length, and this is very computationally expensive requirement. However, if the spanwise domain length is insufficient, unanticipated large oscillation in aerodynamic force, which is not observed in the experiments, 9,12 is observed, and the effective discussion about the flowfield is difficult.…”

“…9 Comparing C L of the controlled cases (denoted as "OFF") for experiment and LES, the control effects become larger after the dynamic stall compared with before the dynamic stall. C L in the pitching down have large oscillation and whose frequency is the same as the modulation frequency(F + ).…”

“…Here, the induced velocity and other information from which we can estimate the value of D c is not available in the reference. 9 In the current study, the value of D c is set to be 0.25 so that the induced velocity is enough to control the dynamic flowfield, the maximum induced velocity by the steady actuation with D c = 0.25 in a quiescent-field is approximately 0.7 times to the freestream velocity.…”

“…9 Hereafter, all the results are of phase averaged for two pitching cycle except for the instantaneous results.…”

“…[1][2][3][4][5] Since flowfields around stationary airfoils are main target of separation control in most of the previous studies, the discussions on the effectiveness of the plasma actuator on the dynamic flowfields around the moving airfoils had been limited. 6-10 Mitsuo et al 9 concludes that the lift enhancement during the pitching down is achieved by that the vortices generated by the plasma actuator bring entrainment of main flow. Post et al shows similar results that the plasma actuator enhances the lift force during pitching down rather than pitching up.…”