城市建筑表面热辐射场影响因素分析*
摘要：
建筑表面热辐射场是城市热辐射场的重要组成部分,会对城市热环境产生重要影响。本文分析了建筑表面辐射场的形成机制,提出了辐射场热作用评价指标。从材料类型、粗糙度、短波反射比和长波发射率4个方面进行了辐射场的单因素影响分析,发现反射比和发射率影响显著。基于此,采用全面试验法对反射比和发射率的耦合作用进行了多因素分析。研究表明:提出的评价指标能较准确反映表面辐射场的强弱走向;反射比对建筑表面热辐射场的影响最大,其次是发射率,材料类型影响最弱。探讨了表面辐射热作用最强的多因素组合方式,并分析了内因。
Abstract：
The thermal radiation field on building surfaces is an important part of the urban thermal radiation field and has a great impact on the urban thermal environment. This paper analyses the formation mechanism of the radiation field on building surfaces, and puts forward the evaluation indexes of the thermal effect of the radiation field. The single factor influence analysis of the radiation field is carried out from four aspects: material type, roughness, short-wave reflectivity and long-wave emissivity, and it is found that the reflectivity and emissivity have significant effects. Based on this, a comprehensive test method is used to conduct a multi-factor analysis of the coupling effect of reflectivity and emissivity. The research shows that the proposed evaluation indexes can more accurately reflect the strength and weakness trend of the surface radiation field.The reflectivity has the greatest influence on the thermal radiation field of the building surface, followed by the emissivity, and the material type has the weakest influence. The multi-factor combination method with the strongest surface radiant thermal effect is discussed, and the internal causes are analysed.
Keywords:building surface; thermal radiation field; evaluation index; wall radiant thermal index; influencing factor; reflectivity; emissivity; urban thermal environment