Effect of Charge Mobility on Electric Conduction Driven Dielectric Liquid Flow

Electrohydrodynamic (EHD) conduction pumping is associated with the heterocharge layers of finite thickness in the vicinity of the electrodes, generated by the process of dissociation of the neutral electrolytic species and recombination of the generated ions. EHD conduction generated flow relies primarily upon the asymmetry of the electrodes where the flow is always directed toward the specific direction regardless of the electrodes polarity. However, the difference in the mobilities of positive and negative charges could play an important role when studying the pumping performance. This paper studies the effects of charge mobility and its difference between the positive and negative charges on the heterocharge layer structure and generated flow. The numerical simulation is conducted for a 2D rectangular channel with the electrodes embedded against the channel wall. The net flow generated for the symmetric electrodes is physically illustrated while the impact of mobility difference on the generated flow for the case of asymmetric electrodes is studied as well.