新型辐射制冷材料——相变蓄冷耦合降温屋面的热性能研究

Thermal performance of a PCM slab roof combined with new radiative cooling materials

为提高相变屋面的蓄冷效率和降温效果,提出了一种新型光谱选择性辐射制冷材料-相变蓄冷耦合降温屋面。建立了耦合降温屋面的数值计算传热模型。以福州地区为研究对象,分析了7种已商业化相变材料耦合降温屋面的热性能,并与无新型光谱选择性辐射制冷材料的传统相变屋面和普通屋面进行对比。结果发现,新型辐射制冷材料可有效降低屋面外表面的温度波动和峰值温度,提高相变材料的潜热利用率。6月1日至9月30日期间,相变材料同为RT25HC的耦合降温屋面比传统相变屋面可减少159%的空调供冷量。室外空气温度与天空有效温度的温差越大,耦合降温屋面相比于传统相变屋面的节能优势越显著。

A PCM slab roof combined with new spectrally selective radiative cooling materials was proposed to improve the cold charging efficiency and cooling effect of PCM slab roof.A computational heat transfer model of the coupled cooling roof was established.Taking Fuzhou area as the research object,the thermal performance of the coupled cooling roofs made of seven commercially available PCMs was investigated and compared with the traditional PCM slab roofs without new radiative cooling materials and ordinary roofs.It is found that the new radiative cooling materials can effectively reduce the temperature fluctuation and peak temperature of the outer surface of the roof,and improve the latent heat utilization rate of the PCM.From June 1 to September 30,the coupled cooling roof with RT25HC PCM can reduce the air conditioning cooling capacity by 159%compared with the traditional phase change roof.The greater the difference between outside air temperature and effective sky temperature,the more significant the energy saving advantage of the coupled cooling roof compared with the traditional phase change roof.