A numerical study on the effect of the electrode voltage on the near-electrode layers in leaky dielectric liquids

The effect of the electrode voltage on the near-electrode layers in leaky dielectric liquids is investigated numerically employing a code developed in OpenFOAM. The Frumkin-Butler-Volmer kinetics responsible for the ion transfer at the electrode surface is accounted for using the experimental data for the faradaic reactions. A novel approach is proposed to calculate the compact layer thickness ramifying from the seminal Stern model. Moreover, a numerical algorithm is suggested to calculate the compact layer thickness for high values of potential applied at the electrodes. The impact of the electric potential on the thickness of the compact and polarized layers and the ionic transport are also investigated in the context of a two-dimensional microchannel flow. The polarized layer is defined as the distance from the surface of the compact layer where the absolute net charge falls to 1% of the maximum absolute value occurring near the compact layer. The electro-hydrodynamic flow in the channel is subjected to two opposite electrodes with opposite polarities resembling situations occurring in the electrostatic atomizers.