建筑中的玻璃 发射率的测定

[中文适用范围]： 本文件规定了测定玻璃和涂层玻璃表面在室温下发射率的程序。发射率对于考虑在283 K标准温度下表面辐射传热是必要的，用于根据ISO 9050[5]、ISO 10291[6]、ISO 10292[7]和ISO 10293[8]确定玻璃的U值和总太阳透射比。该程序基于在红外区域不透明材料的近法向入射分光光度镜面反射率测量，不适用于具有以下至少一种特征的玻璃组件：a) 具有粗糙或结构化表面，入射辐射被漫反射；b) 具有曲面，入射辐射以不适合到达检测器的角度规则反射；c) 红外透明。然而，只要其表面平坦且非漫射（见非漫射玻璃组件）且在红外区域不透明（见红外区域不透明玻璃组件），可以谨慎应用于任何玻璃组件。尽管本文件包括透射率测量，但它们仅用于检查试样在红外区域是否不透明（见红外区域不透明玻璃组件）。如果试样在红外区域透明，则本文件不适用。 [外文原描述]： This document specifies a procedure for determining the emissivity at room temperature of the surfaces of glass and coated glass. The emissivity is necessary for taking into account heat transfer by radiation from surfaces at the standard temperature of 283 K in the determination of the U value and of the total solar transmittance of glazing according to ISO 9050[5] , ISO 10291[6] , ISO 10292[7] , and ISO 10293[8] . The procedure, being based on spectrophotometric specular reflectance measurements at near normal incidence on materials that are non-transparent in the infrared region, is not applicable to glazing components with at least one of the following characteristics: a) with rough or structured surfaces where the incident radiation is diffusely reflected; b) with curved surfaces where the incident radiation is regularly reflected at angles unsuitable to reach the detector while using specular reflectance accessories; c) infrared transparent. However, it can be applied with caution to any glazing component provided its surfaces are flat and non-diffusing (see non-diffusing glazing component) and it is non-transparent in the infrared region (see glazing component non-transparent in the infrared region). Although transmittance measurements are included in this document, they are only necessary to check if the specimen is non-transparent in the infrared region in the context of this document (see glazing component non-transparent in the infrared region). If the specimen is transparent in the infrared region, this document is not applicable.