Numerical simulation of annular electroconvection in a dielectric liquid induced by unipolar injection

We performed a numerical study of two-dimensional electroconvection in a dielectric liquid contained between two concentric circular cylinders with the radius ratio of 0.5. The convection is induced by unipolar injection from the inner or outer cylinder. Both the weak and strong injection regimes were considered. We determined the linear stability criterion from direct numerical results and compared them with the values predicted by the stability analysis. Perfect agreements were found for all the cases we considered. At the threshold of motion, we observed a steady and a chaotic flow pattern for strong and weak injection, respectively. These results share strong analogy with the previous findings with the planar configuration.