LAUSR

Abstract In this paper, the electro-thermo convection (ETC) of a perfectly insulted liquid induced by two energized and heated circular cylinders in a cold square cavity is numerically discussed. The abundant flow motion phenomenen are comprehensive results of the buoyancy force and Coulomb force. A newly developed unified lattice Boltzmann (LB) model for flow field, electric potential, charge density and temperature field is applied to direct numerical simulations. Influences of Rayleigh number R a , electric Rayleigh number R a E on heat transfer enhancement are studied under strong charge rejection regime. Based on the numerical results, it is found that the efficiency of heat transfer decreases with the rise of R a , and the contributions made by external electric field for heat transfer enhancement can be ignored when R a is sufficiently large. While the heat transfer capacity always enhances as the increase of R a E , especially when parameter R a E exceeds a critical threshold. Additionally, the effects of geometric parameter δ on heat transfer coefficient are also analyzed.