Numerical instantiation of complex open-cell metal foam microstructure and evaluation of its thermal performance on the melting of composite phase change material

The melting of paraffin‑aluminum composite PCM with stochastic open-cell metal foam digitally synthesized with a novel numerical approach is investigated via an enthalpy-based double population lattice Boltzmann method. The influences of the geometry of the metal foams, including the volume fraction, the average pore size, the pore size distribution as well as the pore shape, on the melting performance are well discussed and analyzed. The results demonstrate that the presence of highly conductive metal foam promotes the melting rate only when its volume fraction exceeds a certain threshold. Furthermore, increasing the average pore size or widening the pose size distribution when the volume fraction is fixed is not beneficial to the acceleration of melting. Besides, the pore shapes are proved to have little effect on the overall melting performance. Therefore, it is concluded that the optimized design strategy of such composite PCM with highly conducive metal foams is to utilize small and uniform pore sizes.