Thermal performance analysis of phase change materials composed of double layers considering heating and cooling period

The bulk-type phase change materials (BPCM) with the paraffinic PCM such as n-octadecane, n-eicosane and n-docosane was prepared. The thermal conductivity analysis shows that the thermal conductivity of BPCM is higher than that of pure PCMs, after these PCMs were packed. The thermal properties of the BPCM were characterized by DSC and a TCi thermal conductivity analyzer, and the thermal performances of the mixed PCM and BPCM were evaluated by cycling test and heat transfer analysis. In addition, the thermal performance of the double-layer BPCM was conducted to assess applicability of the PCMs in summer and winter.