建筑水平屋面对流换热特性实验研究

本文分析了现阶段建筑外表面对流换热研究存在的问题，设计了一种用于现场实测建筑外表面对流换热特性的萘升华方法，并利用该方法对高大单体建筑水平屋面的对流换热特性做了测量。实测结果表明建筑屋面的对流换热系数和屋面上方的代表风速成正比，代表风速在5.6m/s以内时，对流换热系数在5-50W/m2K。通过分析表明萘试件表面的温度波动和屋面和空气之间的温差对实测结果影响不大。本文考虑了建筑尺度对对流换热的影响，以风登陆屋面沿风向到测点的距离为代表长度，对实测结果做了无量纲化处理，得到了考虑到建筑尺度的建筑屋面对流换热无量纲准则。

Experimental Study on Heat Transfer Characteristics for Horizontal Roof of Building

A new naphthalene sublimation technology was designed for field measuring the outside convective heat transfer coefficient (CHTC) of building roof in this paper, after analysising recent problem in study of CHTC on building surface. A field measurement using this method was performed on a real big building. The experimental results show that the CHTC on building roof have positive linear relation with representive wind velocity at 1.6m high. The CHTC on building roof was ranged in 5-50 W/m2K scope, When the representive wind velocity located within 5.6m/s. The variation of temperature of naphthalene test specimens surface and the temperature different between air and building roof was not affect measuring reslut.A dimensionless corelation about the convective heat transfer characteristic was obtained through considering the dimension effect of the building roof by choosing the distance from piont at the edge of the roof where the air reach the roof to the measuring point as the representive length.