Numerical study of a hybrid thermal lattice Boltzmann method for pool boiling heat transfer on a modeled hydrophilic metal foam surface

Abstract

In this paper, a numerical study is conducted to investigate pool boiling heat transfer on a modeled hydrophilic metal foam surface. A pseudopotential multiple-relaxation-time (MRT) lattice Boltzmann (LB) method is employed to solve the flow field, and a finite-difference (FD) scheme is applied to solve phase change. Thermodynamic nonuniformity is largely avoided by adjusting the forcing term’s corresponding parameters. The metal foam structure is simplified as a staggered square array. Both the bottom wall and solid squares are set as constant temperature boundary. Three kinds of boiling stages on smooth and metal foam surfaces are observed at different wall superheats. The effect of the metal foam porosity and pore size on pool boiling heat transfer is studied. Then boiling curves are obtained to analyze heat transfer performance and bubble behavior under several wall superheats. Finally, numerical simulations of pool boiling under microgravity conditions were performed. The bubble behavior shows great agreement with that of related experimental results, with qualitative proof of the correctness of the model.