Phase change material(PCM)can reduce the indoor temperature fluctuation and humidity control material can adjust relative humidity used in buildings.In this study,a kind of composite phase change material particles(CP...Phase change material(PCM)can reduce the indoor temperature fluctuation and humidity control material can adjust relative humidity used in buildings.In this study,a kind of composite phase change material particles(CPCMPs)were prepared by vacuum impregnation method with expanded perlite(EP)as supporting material and paraffin as phase change material.Thus,a PCM plate was fabricated by mould pressing method with CPCMPs and then composite phase change humidity control wallboard(CPCHCW)was prepared by spraying the diatom mud on the surface of PCM plate.The composition,thermophysical properties and microstructure were characterized using X-ray diffraction instrument(XRD),differential scanning calorimeter(DSC)and scanning electron microscope(SEM).Additionally,the hygrothermal performance of CPCHCW was characterized by temperature and humidity collaborative test.The results can be summarized as follows:(1)CPCMPs have suitable phase change parameters with melting/freezing point of 18.23°C/29.42°C and higher latent heat of 54.66 J/g/55.63 J/g;(2)the diatom mud can control the humidity of confined space with a certain volume;(3)the combination of diatom mud and PCM plate in CPCHCW can effectively adjust the indoor temperature and humidity.The above conclusions indicate the potential of CPCHCW in the application of building energy efficiency.展开更多
With the large latent heat and low cost, the paraffin has been widely used in battery thermal management(BTM) system to improve the efficiency and cycling life of power battery. The numerical model of paraffin melting...With the large latent heat and low cost, the paraffin has been widely used in battery thermal management(BTM) system to improve the efficiency and cycling life of power battery. The numerical model of paraffin melting in a cavity has been established, and the effects on the solid–liquid phase change process have been investigated for the purpose of enhancing the heat transfer performance of paraffin-based BTM system. The results showed that the location of the heating wall had great effects on the melting process. The paraffin in the cavity melted most quickly when the heating wall located at the bottom. Furthermore, the effects of thermal conductivity and the velocity of the slip wall have been considered. The gradient of liquid fraction increased with the increase in thermal conductivity, and the melting process could be accelerated or delayed by the slip wall with different velocity.展开更多
基金Project(51408184)supported by the National Natural Science Foundation of ChinaProject(E2017202136)supported by the Natural Science Foundation of Hebei Province,China+1 种基金Project(BSBE2017-05)supported by the Opening Funds of State Key Laboratory of Building Safety and Built Environment and National Engineering Research Center of Building Technology,ChinaProject(QG2018-3)supported by Hebei Provincial Department of Transportation,China
文摘Phase change material(PCM)can reduce the indoor temperature fluctuation and humidity control material can adjust relative humidity used in buildings.In this study,a kind of composite phase change material particles(CPCMPs)were prepared by vacuum impregnation method with expanded perlite(EP)as supporting material and paraffin as phase change material.Thus,a PCM plate was fabricated by mould pressing method with CPCMPs and then composite phase change humidity control wallboard(CPCHCW)was prepared by spraying the diatom mud on the surface of PCM plate.The composition,thermophysical properties and microstructure were characterized using X-ray diffraction instrument(XRD),differential scanning calorimeter(DSC)and scanning electron microscope(SEM).Additionally,the hygrothermal performance of CPCHCW was characterized by temperature and humidity collaborative test.The results can be summarized as follows:(1)CPCMPs have suitable phase change parameters with melting/freezing point of 18.23°C/29.42°C and higher latent heat of 54.66 J/g/55.63 J/g;(2)the diatom mud can control the humidity of confined space with a certain volume;(3)the combination of diatom mud and PCM plate in CPCHCW can effectively adjust the indoor temperature and humidity.The above conclusions indicate the potential of CPCHCW in the application of building energy efficiency.
基金supported by the National Natural Science Foundation of China(51406223)
文摘With the large latent heat and low cost, the paraffin has been widely used in battery thermal management(BTM) system to improve the efficiency and cycling life of power battery. The numerical model of paraffin melting in a cavity has been established, and the effects on the solid–liquid phase change process have been investigated for the purpose of enhancing the heat transfer performance of paraffin-based BTM system. The results showed that the location of the heating wall had great effects on the melting process. The paraffin in the cavity melted most quickly when the heating wall located at the bottom. Furthermore, the effects of thermal conductivity and the velocity of the slip wall have been considered. The gradient of liquid fraction increased with the increase in thermal conductivity, and the melting process could be accelerated or delayed by the slip wall with different velocity.
