EHD Plasma Actuators Utilising a Dielectric Barrier Discharge,

In the present work the electro-hydro-dynamic (EHD) process through which the electri-cal energy of a surface dielectric barrier discharge (DBD) is converted into kinetic energy of the aerodynamic flow in the boundary layer above the DBD panel surface, is considered. The results of the experimental activity carried out in the Lab of Magnitofluid-Dynamic Engi-neering and Plasmas of the University of Bologna, are analyzed. The aim of the analysis is to derive design rules to utilize during the development of surface dielectric barrier discharge devices for aerodynamic applications. The experiments show that electrostatic force is re-sponsible of the EHD interaction. It accelerates the ions of the plasma sheath in front of the plasma filaments traveling on the DBD panel surface. The momentum acquired by the ions is transferred to the neutral particles of the gas by collision. The EHD process is observed to depend on the applied voltage and on the supply frequency. Increases of the voltage and of the supply frequency are followed by increases of the EHD interaction with acceleration of the flow in the region above the DBD panel. An increase of the length travelled by the plasma filament would cause an increase of the average value of the electrostatic force. How-ever this can be done by changing the electrical configuration. In order to do this in a proper way further studies are necessary.