Direct Numerical Simulation on Melting Phase Change Behavior in Open-cell Metal Foam

Abstract This study presented a pore-scaled numerical simulation on the melting phase change heat transfer of a phase change material (PCM) impregnated in open-cell metal foam. Idealized tetrakaidecahedron was selected as the representing unit cell (UC) to mimic the real foam microstructure and an assembly of tetrakaidecahedron UCs with six lines and three rows was built for computation. Phase change heat transfer in PCM and coupled heat transfer between PCM and metallic ligaments were directly simulated. To address the contribution of natural convection in the melting phase to the overall melting time and pore-scaled melting interface, natural convection in the interstitial fluid was modeled and compared with the conduction-dominated case. Results demonstrated that micro-foam can significantly accelerate the melting phase change rate and further enhancement was observed at pore scale when natural convection in the melting phase was triggered on.