严寒地区建筑外窗冷辐射特性研究

发布时间：2018-05-21 20:22

本文选题：严寒地区 + 外窗　；参考：《河北建筑工程学院》2017年硕士论文

【摘要】：在严寒地区的寒冷冬季,由于室外温度很低,建筑外窗与外界环境存在着强烈的热交换,使得室内靠近窗户的人员会受到明显的冷辐射,从而感到更加寒冷,产生不舒适感。鉴于此现象本文在没有考虑太阳辐射的影响下,着重分析了严寒地区冬季夜间外窗玻璃的冷辐射效应,力求从机理上探究改善外窗玻璃冷辐射的方法,并为本文提出的使用外置窗帘来减轻外窗冷辐射效应的应用提供一定的理论依据。本文首先在严寒地区冬季夜间自然条件下,对搭建的实验小室热环境参数进行了测量,针对实验结果,分析了外窗冷辐射效应下室内的热环境特征。并计算了中空玻璃各部分的传热损失,计算结果显示辐射传热是普通中空玻璃主要的传热热损失形式,且所占总热损失的比例随着室内外温差的增加而增大,实验最后测试了增设外置保温窗帘对改善外窗冷辐射现象的效果情况。本文同时也运用了CFD数值模拟的方法,首先对单独的三维中空玻璃模型进行了传热特性模拟,并考虑了空气夹层的辐射-对流耦合传热问题。同时,本文结合真实的环境条件,采用了一种新的热边界条件设定方法,即基于室外气象信息来给定外窗玻璃的热边界条件,结果表明此方法的模拟值更加接近实际。进而又对整体建筑进行了室内热环境数值模拟,通过温度以及速度分布云图可以更加形象地得出外窗对室内热环境的影响规律。结果显示:严寒地区冬季夜间,室内空气温度分布在外窗玻璃冷辐射的作用下出现明显的分层,导致室内温度场不均匀现象严重。而当增设外置窗帘后显示,外置窗帘可以大幅减弱外窗辐射换热热损失,大大降低了室内的不对称辐射,对室内热舒适环境的改善效果显著,应该在严寒地区大量推广应用。
[Abstract]:In cold winter, there is a strong heat exchange between the outside window and the outside environment because of the low temperature in the cold winter area. The people near the window will be exposed to obvious cold radiation, which makes it feel cold and uncomfortably feeling. The cold radiation effect of window glass in winter at night in the area is to explore the method to improve the cold radiation of the outer window glass from the mechanism, and provide some theoretical basis for the application of the external curtain to reduce the cold radiation effect of the outer window. The environmental parameters are measured. In view of the experimental results, the characteristics of the indoor thermal environment under the cold radiation effect of the outer window are analyzed. The heat transfer loss of each part of the insulating glass is calculated. The calculation results show that the radiation heat transfer is the main heat loss form of the ordinary insulating glass, and the proportion of the total heat loss is increased with the temperature difference between the room and the outside. In addition, the experiment finally tested the effect of adding external thermal insulation curtain to improve the cold radiation phenomenon of outer window. At the same time, this paper also used the CFD numerical simulation method. First, the heat transfer characteristics of the separate three-dimensional hollow glass model were simulated, and the radiative convection coupled heat transfer problem of the air interlayer was considered. In real environment conditions, a new thermal boundary condition setting method is adopted, which is based on the outdoor weather information to give the thermal boundary conditions of the window glass. The results show that the simulation value of the method is closer to the reality. Then the indoor thermal environment is simulated for the whole building, and the temperature and velocity distribution cloud can be more shape. The effect of external windows on the indoor thermal environment was obtained. The results showed that the temperature distribution of indoor air appeared obviously in the cold area of the outside window during the winter night in the cold area, which resulted in the serious inhomogeneous temperature field in the indoor temperature field, and the external curtain could greatly weaken the radiation heat transfer of the outer window after the external curtain was added. The heat loss greatly reduces the indoor asymmetric radiation, and improves the indoor thermal comfort environment. It should be widely applied in cold regions.
【学位授予单位】：河北建筑工程学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU111.4

【参考文献】