Microencapsulated phase change material (MEPCM) saturated in metal foam as an efficient hybrid PCM for passive thermal management: A numerical and experimental study

This article reported an efficient hybrid phase change material (PCM) for passive thermal management that integrated micro-encapsulated phase change material (MEPCM) and metal foam. This PCM composite was aimed to enhance the heat transfer of MEPCM, while avoid the leakage of molten phase change material (PCM). We proposed a two-energy equation model and experiment demonstration to investigate phase change heat transfer inside MEPCM/foam composite. The surface/internal temperatures, interface evolution and non-equilibrium heat transfer in the composite were discussed. Results showed that the pure MEPCM was not suitable for thermal management due to the low thermal conductivity. The wall temperature of the MEPCM/foam composite was only half of the pure MEPCM attributed to the latent heat absorption of MEPCM and thermal enhancement of metal foam. The higher porosity composite obtained higher surface temperature, and also consumed less time to start phase change due to the lower effective thermal conductivity. Besides, better thermal control was achieved by the MEPCM/foam composite with higher pore density attributed to its larger volumetric area. The employment of metal matrix made the internal temperature distribution more homogeneous and reduced the inside temperature gradient.