新建建筑外保温围护结构热质耦合传递

Simulations on heat and mass coupling transfer in exterior insulated envelope of new building

为分析新建建筑围护结构的干燥过程,对哈尔滨地区新建建筑围护结构干燥过程的热湿耦合传递进行模拟.考虑液态水的渗透和冬季围护结构内湿分结冰的情况,以液态体积含湿量梯度为质驱动势,以温度梯度为热驱动势,建立不同干燥时段的热质耦合传递质能平衡方程,并对模拟结果进行分析.结果表明:新建建筑围护结构的干燥速率第一年最快,尤其是前几个月;由于围护结构较大的初始含湿量和冬季外侧结冰量,第一年围护结构的保温性能是最差的;在相同的室外气候条件下,与第十年冬季的传热系数相比,第一年要增加约10%,严重影响第一年的建筑能耗.

In order to analyze the drying of enclosure on new building in its initial use period, the heat and moisture coupling transfer in new building enclosure in Harbin was simulated. The permeability and freezing of the liquid water in porous building material were considered. The moisture content gradient was used as mass transfer driving forces, and the temperature gradient was used as heat transfer driving forces. Heat and mass transfer equations of different drying performances were built. The analysis of simulation results indicates that the drying rate of the new building is significantly high in the first year, especially in the first few months. Insulation performance of the wall in the first winter is the worst due to the high initial moisture content and freezing ice in porous insulation material. For the simulated enclosure, the maximum heat transfer coefficient in the first year is about 10% higher than that in the tenth year under the same outdoor climatic conditions. Changes in the heat transfer coefficient （thermal resistance） during initial drying have notable effects on the energy consumption of building.