建筑外皮相变隔热研究(Ⅱ)——建筑相变隔热设计原理与方法

摘要

本文首先说明了相变隔热设计中相变温度和相变材料用量的确定原理,而后详细阐述了相变温度和相变材料用量的确定方法,最后以厦门普通屋面为例,分析说明了相变隔热设计的具体应用.实例计算结果表明:1)利用相变材料对现有围护结构进行隔热,一般只需几mm的相变层厚度,其热阻可忽略不计,相变隔热设计可基于无相变层来考虑；2)相变材料及其用量的确定与室内外热作用、围护结构构造及相变层位置有关,需通过计算选定；3)室内侧热扰(如房间通风)对围护结构外表面温度及热流影响很小,当相变材料拟置于建筑外表面时,相变温度及相变材料用量的确定可仅基于室外侧热扰考虑,相变隔热设计相对简单.%In this paper,the theory and method for determining the phase transition temperature and amount of phase change material(PCM) in thermal insulation design were firstly introduced. And then, taking the ordinary roof in Xiamen as an example, the application of the presented design method for thermal insulation with PCM was illustrated. The calculated results indicated that when PCM was used in building envelope for thermal insulation, only several millimeters were required. Moreover, because its thermal resistance could be neglected, the thermal insulation design with PCM could be carried out based on the assumption that PCM layer was not exist. Furthermore, the determination of PCM's type and its amount was associated with thermal effects of indoor and outdoor, material structures of envelope and the position of PCM layer, it should be selected based on the calculation. In addition, the indoor thermal effect,such as room ventilation,had very small impact on exterior surface temperature and heat flux,when the PCM was located on the exterior surface, the phase transition temperature and amount could be calculated only based on the outdoor thermal effect, therefore, the thermal insulation design with PCM became relatively simple.