Numerical study of flow characteristics around a NACA 4412 asymmetric airfoil under the influence of electric field

Electrohydrodynamic actuator is one of the newest devices in flow control techniques which can delay separation point and reduce the drag coefficient by inducing external momentum to the boundary layer of the flow. In this paper، a 2-D numerical approach was implemented to analyze the presence of electrohydrodynamic actuator on the incompressible، turbulent، steady flow over a NACA 4412 asymmetric airfoil. In this regards، the flow field and aerodynamic characteristics such as the drag and pressure coefficient were evaluated through the variety of attack angles، applied voltages، the location of emitting electrode، and the distance from the upper surface of the airfoil. The numerical results indicate that the drag coefficient with the presence of an electric field decreases with the enhancement of the supplied voltage but increases when the attack angle is augmented. In addition، the location of separation point significantly depends on the position of emitting electrode and the distance between the emitting electrode and the collecting electrode. On the other hand، according to the results، the Electrohydrodynamic effects cause the diminution of the wake region over the airfoil.