Lattice Boltzmann analysis of conjugate heat transfer in the presence of electrohydrodynamic flow

Abstract

The externally imposed direct current (DC) electric field mightily impacts on the conjugate heat transfer existing somewhere between the solid and liquid phases, which is numerically investigated via Lattice Boltzmann method (LBM) in this paper. The model is a square cavity filled with dielectric liquid, in which has a centred heat-generating solid body, and the spatially inhomogeneous physical properties such as thermal conductivity, heat capacity, permittivity and mobility are considered distinctively. The lattice Boltzmann method is used to solve the entirely coupled equations and the developed code is first verified by three cases for the hydrostatic solution, conjugate heat transfer with and without heat source. The LBM results show the highly agree well with both the derived analytical solution and the results obtained by other papers. Then, enhancement effect of the flow and heat transfer when electrohydrodynamic (EHD) forces in existence are studied under the different governing parameters and the internal heat source intensity. It is found that the solid-liquid two phases conjugate heat transfer can be significantly enhanced when applying a DC electric field across the domain.