Understanding of electrohydrodynamic conduction pumping phenomenon

Electrohydrodynamic (EHD) phenomena can be applied to enhance and control mass and heat transfer in both terrestrial and microgravity environments. The emerging EHD conduction pumping technique shows its potential as an active control method of the flow distribution. The EHD conduction pumping is associated with the heterocharge layers of finite thickness in the vicinity of the electrodes, which are based on the process of dissociation of the neutral electrolytic species and recombination of the generated ions. This paper theoretically and experimentally studies the EHD conduction phenomenon in a dielectric liquid. The analytical solutions provide the non-dimensional distributions of electric field and charge density in the vicinity of the electrodes. The characteristic heterocharge layer thickness is also theoretically predicted. Measured pressure heads and current levels are compared with the theoretical results. The EHD conduction pump presented here is capable of electrically driving and controlling the dielectric liquid flow motion in a single-phase loop. (C) 2004 American Institute of Physics.