Numerical observation of stationary and oscillatory electro-thermo-convection in a plane layer of dielectric liquid

In this paper, we numerically investigated the electro-thermo-convection in a plane layer of non-isothermal dielectric liquid induced by unipolar charge injection. The case that the injection was from below and heating from above was considered. The ionic mobility is assumed to vary linearly with temperature. Results with two heating modes (weakly and strongly stabilizing thermal gradients) are presented. Three distinct flow structures, namely as the space charge modified Bénard convection, the thermally modified space charge convection and the oscillatory convection, were observed. By comparing numerical results with the ones provided by the stability analysis approach, fairly good agreement was showed, which highlighted the effectiveness of our numerical algorithm.