Comparative analysis of numerical simulation and PIV experimental results for a flow caused by field-enhanced dissociation

Abstract

The paper studies a particular electrode system, two flat parallel electrodes with a dielectric plate having a small circular hole between them. Its main feature is that the region of the strong electric field is located far from metal electrode surfaces, which permits one to preclude the injection charge formation and to observe field-enhanced dissociation (the Wien effect) leading to the emergence of electrohydrodynamic (EHD) flow. The described electrode system was studied by way of both computer simulation and experiment. The latter was conducted with the help of the particle image velocimetry (or PIV) technique. The numerical research used trusted software package COMSOL Multiphysics, which allows solving the complete set of EHD equations and obtaining the EHD flow structure. Basing on the computer simulation and the comparison with experimental investigation results, it was concluded that the Wien effect is capable of causing intense (several centimeters per second) EHD flows in low-conducting liquids and has to be taken into account when dealing with EHD devices.