空穴效应下泡沫金属复合相变材料热性能数值模拟OACSTPCD

A randomly distributed cavity model was constructed for 3D metal foam composite phase change ma-terials(PCMs),and the multi-relaxation time lattice Boltzmann method was used to explore the cavity effects with different volume fractions,distribution locations,and thermal conductivity ratios of metal foam to PCM at the cavity scale.The results show that,with the increase of the cavity volume fraction,the heat transfer rate and latent heat storage capacity of composite PCMs would decrease.At a Fourier number of 0.7,compared to the case without cavity,the heat storage decreases respectively by 3.2%,9.0%,and 13.0%for a cavity volume fraction of 2.4%,7.6%,and 11.7%,respectively.The significant hindering effect on the melting process of com-posite PCMs occurs in the case of cavities with a volume fraction of 3%and concentrated near the high-tempera-ture wall.The cavities act as an adiabatic layer,extending the complete melting time of composite PCMs by 6.1%.To weaken the cavity effect,the metal foam skeleton with a thermal conductivity ratio of more than 100 can be selected to improve its leading role in heat transfer.