Numerical Study of Fluid Dynamics and Heat Transfer Induced by Plasma Discharges

A numerical investigation is conducted to explore the evolution of a plasma discharge and its interaction with the fluid flow based on a self-consistent fluid model which couples the discharge dynamics with the fluid dynamics. The effects of the applied voltage on the distribution of velocity and temperature in initially static air are parametrically studied. Furthermore, the spatial structure of plasma discharge and the resulting force contours in streamwise and normal directions are discussed in detail. The result shows that the plasma actuator produces a net force that should always be directed away from the exposed electrode, which results in an ionic wind pushing particles into a jet downstream of the actuator. When the energy added by the plasma is taken into account, the ambient air temperature is increased slightly around the electrode, but the velocity is almost not affected. Therefore it is unlikely that the induced flow is buoyancy driven. For the operating voltages considered in this paper, the maximum induced velocity is found to follow a power law, i.e., it is proportional to the applied voltage to the 3.5 power. This promises an efficient application in the flow control with plasma actuators.