Thermal performance study of PCM embedded radiant cooling ceiling assisted by infrared-transparent silicon wafers

Phase change materials embedded radiant chilled ceiling (PCM-RCC) systems are great for cutting peak power demand and boosting energy efficiency, but they might not work as well in really humid areas due to condensation issues. Infrared-transparent silicon wafer-assisted PCM-RCC (ISW-assisted PCM-RCC) is proposed to improve the cooling capacity in this study. A heat transfer model of ISW-assisted PCM-RCC is established and its reliability is verified. Effects of thermal conductivity, phase change temperature, and control strategy on the thermal performance of ISW-assisted PCM-RCC are discussed by using the model. The simulation results show that the thermal conductivity of PCM is recommended to be above 0.6 W/(m & sdot;K), and the temperature difference between the lower limit of the selected PCM phase transition temperature range and the chilled water temperature should not be less than 1degree celsius. The maximum cooling power of the system is more than 80 W/m2, 46 % higher than the non-condensing cooling capacity of traditional RCC at 70 % relative humidity conditions. Interestingly, the prolonged cold energy storage strategy at night should be avoided which is not friendly to the energy efficiency of the system. In short, the combination with ISW is an effective means to increase the cooling capacity of the PCM-RCC.