Experimental flow measurements of electrohydrodynamic convection fields by particle image velocimetry

A method of particle image velocimetry has been proposed for measuring flow velocity of electrohydrodynamic (EHD) convection fields in dielectric liquids. The flow velocity is calculated from the average moving distance and direction of the tracer particles traveling along with the fluid flow. The method has the great advantage that it enables the continuous measurement of the velocity distribution of unsteady flow fields. Some interesting velocity distributions are obtained for silicone oil which is electrically and thermally stressed under non-uniform electric fields. The experimental results show an analogy between natural convection and the EHD convection. We conjecture that the EHD convection is formed as a driving action causing energy release at the tip of the electrode.