夏热冬冷地区外保温墙体凝露特性及防结露措施分析  

Analysis of condensation characteristics and anti-condensation measures of external thermal insulation wall in hot summer and cold winter areas

作　　者：邹凯凯 李舒宏[1] Zou Kaikai;Li Shuhong(School of Energy and Environment,Southeast University,Nanjing 210096,China)

机构地区：[1]东南大学能源与环境学院,南京210096

出　　处：《东南大学学报（自然科学版）》2018年第4期654-661,共8页Journal of Southeast University：Natural Science Edition

基　　金："十三五"国家科技支撑计划资助项目(2017YFC0702501);"十二五"国家科技支撑计划资助项目(2014BAJ01B05-2)

摘　　要：为降低墙体内部结露的危害,建立以温度和相对湿度为计算驱动势的一维热湿耦合传递模型,对夏热冬冷地区常见的EPS外保温墙体进行凝露特性及相关防结露措施效果的分析.通过模拟,对比分析了南京、南昌、长沙及重庆地区EPS外保温墙体冬夏季工况条件下的热湿分布情况.在夏季工况下,4个地区墙体的保温层与基层材料界面处相对湿度分别高达86.43%,82.45%,86.07%,82.61%,具有较高的结露风险.以南京地区为例,对采用空气层、隔汽层2种防结露措施的EPS外保温墙体进行防结露效果分析.结果表明,在保温层与基层材料界面处设置15 mm空气层,可降低保温层最大相对湿度2.31%;而在室外保温层外侧设置隔汽层,虽然降低了夏季工况下的相对湿度,但将保温层冬季相对湿度提高至91.26%,具有不利影响.因此夏热冬冷地区冬夏季工况下,外保温墙体采取空气层防结露措施比隔汽层更有利.In order to reduce the damage caused by the condensation in the wall,a one-dimensional heat and moisture coupling transfer model based on temperature and relative humidity was established.The condensation characteristics and the anti-condensation measures of EPS(expanded polystyrene)external thermal insulation wall in the hot summer and cold winter areas were analyzed.Through the simulation,the distributions of heat and moisture inside EPS thermal insulation wall in Nanjing,Nanchang,Changsha and Chongqing under the summer and winter conditions were compared and analyzed.Under the summer conditions,the relative humidity at the interface between the insulation layer and the base material of wall in the four areas is as high as 86.43%,82.45%,86.07%and 82.61%,respectively,which has a high dew condensation risk.Taking Nanjing as an example,the anti-condensation effect of the EPS external insulation wall with the anti-dewing measures of air layer and vapor barrier was simulated.The simulation results show that the maximum relative humidity of the thermal insulation layer can be reduced by 2.31%after 15 mm air layer is set at the interface between the thermal insulation layer and the base material of wall.Setting the vapor barrier layer at the surface on the outside of the insulation layer can reduce the relative humidity under the summer conditions,but increase the relative humidity to 91.26%under the winter condition,which has an adverse effect.Therefore,in the hot summer and cold winter areas,the anti-condensation measure of air layer is more favorable than the measure of vapor barrier layer in the external thermal insulation wall under the summer or winter condition.

关 键 词：结露 热湿传递 相对湿度 空气层 隔汽层 

分 类 号：TU111.19[建筑科学—建筑理论]