Numerical Investigation of Conjugate Heat Transfer and Natural Convection Using the Lattice-Boltzmann Method for Realistic Thermophysical Properties

To enable the lattice-Boltzmann method (LBM) to account for temporally constant but spatially varying thermophysical properties, modifications must be made. Recently, many methods have emerged that can conjugate heat transfer (CHT). However, there still is a lack of information on possible physical property range regarding realistic properties. Therefore, two test cases were investigated gain further insight. First, differentially heated cavity filled with blocks was used investigate influence CHT error and stability LBM simulations. Reference finite volume (FVM) simulations carried out estimate error. It found between 0.5 1.5 recommended fluid relaxation time balance computational effort, stability, accuracy. In addition, properties fluids solids selected whether suitable simulating relevant industry-related applications. For stable simulation, mesh 64 times more lattices needed most extreme case. The second case an insulated heating pad as local source, which in terms accuracy transient simulation compared FVM simulation. fluid-phase mainly determines large thermal solid improve Observed deviations from reference ranged approximately 20% below 1%, depending collision operator combination times. processes temperature spread, are primary constraint.