摘要
建筑围护结构内的热湿耦合传递是一个非常复杂的过程,其研究是降低建筑能耗、评估和预防湿害、提高室内热舒适性、室内卫生及优化围护结构性能的基础。新建节能建筑墙体具有初始含湿量大的特点,若墙体湿积累过大,则容易出现墙体表面剥蚀、渗漏、发霉甚至结构出现损坏的现象。墙体干燥时,传热传质过程同时发生且相互耦合。目前相关热物性仿真软件、理论研究和设计规范主要建立在热传递的基础上,忽略了湿传递的影响,对新建建筑墙体干燥不适用。WUFI~? Pro热湿仿真软件充分考虑了材料本身含湿量、风驱雨、太阳辐射、长波辐射、毛细传输和夏季结露等典型气候的影响,实现了对自然气候条件下建筑构件非稳态热湿性能的真实计算。节能墙体多在外墙添加内外保温层来增加围护结构的传热热阻,且在保温层内外两侧分别添加隔汽层和空气层的措施来防止保温层受潮,最终提高围护结构的保温性能。为墙体美观,多在围护结构的内外两侧分别黏贴墙纸和釉面砖。采用WUFI~? Pro对北京地区2种典型的建筑墙体进行热湿耦合传递模拟,分析新建建筑墙体在不同保温层材料和位置时的干燥过程,以及保温层两侧的隔汽层和空气层、墙体两侧的墙纸和釉面砖对墙体干燥过程的影响。模拟用室外条件为北京典型气象年小时室外气象参数,室内条件设定室内冬季供暖温度T_1=20℃,夏季室内温度设计值T_2=25℃,全年平均相对湿度为50%。模拟外围护结构属于西向,墙体温湿度初始条件为:相对湿度为100%,温度为15℃。模拟结果表明:内保温层的设置非常不利于围护结构的干燥,容易在内保温层和砌块之形成湿积累,降低围护结构的耐久性;EPS、PU和XPS都能降低围护结构含湿量,但EPS更有利于墙体干燥;隔汽层和空气层的添加可一定程度上阻止保温层受潮,避免造成湿�
Heat and moisture coupled transfer in building envelope is a very complicated process. The study is a basis to reduce building energy consumption, evaluate and prevent moisture damage, improve the indoor sanitation, occupant＇s thermal comfort and indoor health environment,and optimize performance of building envelope. New energy saving building wall has the characteristics of the large initial moisture content. If wall moisture accumulation is too large, it＇s easy to have the phenomenon of wall surface erosion, leakage, mould or even the damage of the structure. When the wall is drying, heat and mass transfer processes occur simultaneously and mutual coupling. The current related simulation software in thermal and physical properties, theoretical research and design specification mainly based on heat transfer and ignored the influence of moisture transmission. It does not apply to new buildings. WUFI？ Pro, developed by IBP, is a heat and moisture simulation software. It fully considers the material moisture content,flooding wind rain,solar radiation,long - wave radiation,capillary transmission,the typical weather of condensation in summer and so on. WUFI Pro can accomplish the real calculation of the construction under unsteady thermal performance with natural climate conditions. Energy - saving wall gain more heat transfer resistance by increasing insulation layer of the envelope both inside and outside. Adding the water retarder and the air layer in insulations both sides respectively prevent the thermal insulation layer from being affected with damp. These eventually improve the insulation performance of the envelope. Both inside and outside of the envelope with the glazed tiles and wallpaper paste respectively,for the sake of the wall is beauty. In this article,two typical wall constructions in Beijing were simulated by the heat and moisture simulation software IBP WUFI Pro, the new building wall＇ s drying process indifferent materials and
出处
《建筑节能》
CAS
2017年第9期33-37,44,共6页
BUILDING ENERGY EFFICIENCY
基金
国家自然科学基金资助项目(51206190)
中南大学自由探索计划(2016zzts320)
中南大学教师基金资助项目(2015)
关键词
节能建筑
围护结构
热湿耦合
WUFI
干燥过程
energy - saving building
building envelope
heat and moisture coupled
WUFI
drying process
