湿热地区充气薄膜屋面喷雾降温实验——以ETFE气枕屋面为例
Experiment on cooling effect of inflatable membrane roof mist spray in hot-humid areas—A case study of ETFE cushion roof
摘要：
为明确湿热地区屋面喷雾技术对充气薄膜屋面的降温效果，以广州无限极广场的乙烯-四氟乙烯共聚物（ETFE）气枕屋面为研究对象，通过在夏季典型气候条件下开展实验测试，量化了该技术对屋面表面与下方室内产生的降温效果，分析了屋面内外表面的热流量变化，并建立了以气象参数为自变量的屋面外表面降温效果预测模型。结果表明：喷雾系统在全天产生的外表面与内表面降温范围分别为3.8~12.3 ℃与1.5~2.9 ℃；屋面喷雾可提高室内人员的热舒适水平，室内空气温度与平均辐射温度降温范围分别为0.2~0.3 ℃与0.2~1.0 ℃；在上午与下午时段可使进入室内的传热热流量分别减少21.3%与33.9%，对降低建筑负荷具有积极作用；太阳辐射对屋面外表面降温效果影响最大，其次是风速，而湿球温度的影响最小。该技术不仅可在湿热地区应用，在其他高辐射地区应用仍可实现良好的降温效果。
Abstract：
In order to explicit the cooling effect of mist spray on the inflatable membrane roof in hot-humid areas adequately, an ethylene tetra-fluoro-ethylene (ETFE) cushion roof in Guangzhou Infinity Plaza is selected as the research object. The cooling effects of this technology on the roof surface and the indoor air are quantified by a field experiment under typical climate conditions in summer, the heat flux variations through the interior and exterior roof surfaces are analysed, and a prediction model for assessing the cooling effect of roof exterior surface is established with meteorological parameters as independent variables. The results indicate that the temperature drops of the exterior and interior surfaces generated by spray system are 3.8-12.3 ℃ and 1.5-2.9 ℃, respectively. The roof mist spray can significantly improve indoor thermal comfort, the average drops of the indoor air temperature and mean radiant temperature are 0.2-0.3 ℃ and 0.2-1.0 ℃, respectively. This technique can also reduce the heat flux entering the room by 21.3% and 33.9% in the morning and afternoon, respectively, which has a positive effect on reducing the building cooling load. Besides, the roof cooling effect is most affected by solar radiation, followed by wind speed, and lastly the wet-bulb temperature. This technique can not only be applied to hot-humid areas, but also can generate good cooling effect in other areas with strong radiation.
Keywords:hot-humid area; inflatable membrane roof; mist spray; cooling effect; indoor thermal environment; heat flux