抄録
The coaxial cone to rod electrode system was devised to generate a powerful electrohydrodynamic (EHD) liquid jet and the performance as a liquid pump was investigated using an isothermal weakly conducting liquid, HFC43-10. When a positive dc voltage was applied to the rod electrode, the liquid spouted forcibly from the glass tube outlet installed in the top of grounded conical electrode. The properties of liquid jet: pumping pressure, flow velocity and flow pattern were examined for the electrode systems with various cone angles (θ =40°∼90°) of the conical electrode. The potential distribution in the electrode gap and the conduction current also were measured as a function of applied voltage. In this paper, it is shown that the pumping pressure is almost independent of the cone angle of electrode systems as well as the flow velocity, but is raised effectively by a partial insulating coating of rod electrode surface and the current is reduced by a coating. The potential distribution in the gap revealed the existence of heterocharge layer in the vicinity of the electrode surfaces. It is considered that the EHD pumping in this study is attributed to a space charge layer with single ionic polarity near the rod electrode, which is formed by a non-uniform electric field.
