Surface charge in dielectric barrier discharge plasma actuators

Direct measurements of the dielectric surface potential and its dynamics in asymmetric dielectric barrier discharge (DBD) plasma actuators show that the charge builds up at the dielectric surface and extends far downstream of the plasma. The surface charge persists for a long time (tens of minutes) after the driving voltage has been turned off. For a sinusoidal voltage waveform, the dielectric surface charges positively. With the voltage waveform consisting of nanosecond pulses superimposed on a dc bias, the sign of the dielectric surface charge is the same as the sign (polarity) of the bias voltage. The surface charging significantly affects DBD plasma actuator performance. (C) 2008 American Institute of Physics.