Plasma Actuators – DBD Actuators
Dielectric Barrier Discharge Actuators are electronic devices that can be used for flow control applications. They are generally composed of asymmetric metallic electrodes separated by a dielectric insulation material. When a radio frequency high voltage is applied to the electrodes, weakly ionized plasma is generated in the surrounding air at ambient pressure. The charged particles are accelerated in the created electromagnetic field and transfer momentum to neighboring neutral air molecules by collision. A net body force is generated in the fluid, leading to a zero net mass flux that can be used for flow control applications. The advantage of these actuators over other flow control devices is the lack of moving mechanical parts and real-time control at high frequencies.
Since the development of DBD actuators in 1996, interest in controlling and influencing fluid flows with electric fields has increased continuously. Many experiments have proved the versatile application of DBD actuators. Various experiments have shown the applicability of DBD actuators to boundary layer manipulation in transition and separation control on airfoils or cylinders. DBD actuators can be used in a steady operation mode to constantly add momentum to a boundary layer or operated intermittently in a pulsed mode to actively influence wavelike disturbances responsible for natural transition to turbulence. Theoretically, they can also be used to generate thrust in small aerial vehicles.
Current research projects associated with the use of DBD actuators at TU Darmstadt are the following: