Experimental Investigation of EHD Flow in Wire to Cylinder Electrode Configuration

Abstract

The electro-hydrodynamic (EHD) flow known as “ionic wind”, which takes place in the area between a wire to cylinder electrode configuration under high voltage dc application, was studied. Two set of measurements were carried out in order to determine the relationship between corona discharge current, generated thrust, wind velocity and the applied voltage. The dependence of the EHD flow parameters on the cylinder radius R and the electrode distance d were examined, while the wire radius r and the electrode length L were kept constant at 25�m and 300mm respectively. The experimental investigation confirmed the corona discharge current to voltage relationship according to Townsend’s formula [1], with a very good agreement of the experimental results with theoretical expectations. The force to voltage relationship fits very well to a quadratic polynomial equation. The wind velocity-voltage relationship can be approximated by a linear equation. Parametric analysis showed that increased cylinder radius results in increased current, force and wind velocity with respect to the applied voltage. In contrary, increased electrode distance reduces current, force and wind velocity with respect to the applied high voltage.