Full bifurcation scenarios and pattern formation of laminar electroconvection in a cavity

Abstract

This study numerically investigates the flow structures and bifurcation scenarios of three-dimensional (3D) laminar electroconvection (EC). An efficient parallel lattice Boltzmann model is undertaken to numerically solve the model problem. The results present three steady flow patterns and three pitchfork bifurcations. These three patterns each have one, two, or four charge void cells. The three critical values of electric Rayleigh number Tc are 242, 545, and 665, respectively. There are also two hysteresis loops whose nonlinear criteria Tf are 157 and 435, respectively. An unexpected flow pattern, which has two prism-shaped primary vortex structures, demonstrates the significance of 3D analysis. In addition, we find that the 3D flow in the cavity is more stable by studying the correlation between the 3D and two-dimensional laminar EC. Using dynamic mode decomposition for the flow structures, we reveal that the novel feature is the result of competition between the EC flow structure and the limitation of geometry.