西藏自治区城市围护结构传热系数的修正系数

Correction factor for heat transfer coefficient of city building envelope in Tibet autonomous region

围护结构传热系数的修正系数(iε)是建筑能耗计算过程中的重要参数。然而,目前的iε值对地区气候差异、围护结构类型的考虑都很粗略,特别是对太阳能富集地区。该文在分析的基础上得到了西藏自治区4个典型城市准确的iε值。计算过程中考虑了气候状况、外窗框材、玻璃层数及墙体面层材料等因素的影响。结果表明,西藏自治区的iε值与采暖期室外平均温度相近的地区有很大的差别。因此,该文的结果不仅可使该地区围护结构传热计算更加准确,同时也为窗户类型、墙体表面材料及遮阳措施的合理选用提供了依据。

The correction factor for the heat transfer coefficient of a building envelope （εi） is an important factor in building energy consumption calculations; however, present ei models do not consider climate variations or the specific building envelope designs, especially the effects of the surface characteristics in high solar radiation areas. This paper presents actual εi of values for four typical cities in Tibet autonomous region. The calculations considered the climate variation, the frame materials of the windows, the number of the glass layers, and the building surface conditions. The results show that the εi values in Tibet are quite different from those in other cities with similar average outdoor temperatures during the heating season. Therefore, these not only enable more accurate calculation of heat transfer but also provide better information for choosing window types, building surface materials, and shielding devices.