Conventional passive phase change material(PCM)envelope structure generally uses a single-effect PCM,which is difficult to achieve good heating in winter and heat insulation in summer.A double-effect shaped PCM was proposed and introduced,which was made with a low-temperature single-effect shaped PCM and a high-temperature single-effect shaped PCM by mixing and stirring with 1∶1 mass ratio.The target phase-change temperatures of the low-temperature single-effect shaped PCM and the high-temperature single-effect shaped PCM were 22℃and 27℃respectively.Both the single-effect PCMs used paraffin wax as the matrix PCM and used graphene as the reinforcement material for adsorption and shaping.The main thermophysical parameters of each single-effect PCM and double-effect PCM were tested by using a differential scanning calorimeter.The results presented that the actual phase-change temperature of the low-temperature single-effect PCM was 22.4℃and its phase-change enthalpy was 155.5 kJ/kg.The actual phase-change temperature of the high-temperature single-effect PCM was 27.2℃and its phase-change enthalpy was 169.9 kJ/kg.The double-effect PCM had two phase-change temperatures of 23.0℃and 27.1℃,and the total phase-change enthalpy was 162.2 kJ/kg.The results show that the double-effect PCM maintains the phase-change temperature of each single-effect PCM,and its phase-change enthalpy is the mass-weighted average of the two single-effect PCMs,which validates the feasibility of double-effect phase-change.Further,the calculation methods of the equivalent specific heat capacity and equivalent thermal conductivity of the double-effect PCM were given according to the test result.
关键词
冬夏兼顾/双效相变材料/热物特性/试验测试
Key words
taking both winter and summer into account/double-effect PCM/thermophysical property/experimental study
维普
万方数据