Electrohydrodynamic flow of dielectric liquid around a wire electrode-effect of truncation of onsager function

Electrohydrodynamic flow of a dielectric liquid around a wire electrode sandwiched between two parallel flat-plate electrodes is studied both numerically and experimentally. The Poisson-Nernst-Planck equations for the ion transport and the Navier-Stokes equations for the fluid flow are solved numerically by using a commercial code. Charge generation in a dielectric liquid (dodecane + 0.5% wt Span 80) due to Onsager effect is considered in the ion transport equations. Numerical results well predict the experimental ones both qualitatively and quantitatively. At high electric field the numerical approach slightly over-predicts the flow velocity measured from the experiment, but the level of discrepancy can be further lowered by using a truncated series for the Onsager function.