Experimental Study On The Difference Of Shading Performance Of Building Glass Lighting Roof

With the continuous improvement of architectural design level and technology,glass lighting roof is widely used in large public buildings,but the glass lighting roof brings a broad vision to the indoor environment,not only significantly increases the building energy consumption,but also the indoor thermal environment.A big impact has been made.Building shading is one of the simple and effective passive energy-saving technologies.How to measure and select the appropriate shading form is of great significance to reduce building energy consumption and improve indoor environment comfort.For this purpose,the main research work of this paper is as follows:Firstly,according to the definition of solar heat gain coefficient(SHGC),the outdoor shading performance experiment of FSS ceiling curtain was designed and carried out.The experimental results show that the SHGC value of the FSS ceiling curtain is 0.28;in the indoor heat gain,the short-wave solar radiation accounted for the highest proportion,about 58.93%,followed by the long-wave radiation dose ratio,which was about 35.16%,and the convective heat transfer ratio.The smallest is about 5.91%.Secondly,the wind tunnel recurrence experiment of the outdoor shading performance experiment using the wind tunnel.The experimental results show that the SHGC value measured by the wind tunnel experiment is 0.30,and the deviation of the SHGC value obtained by the outdoor experiment and the wind tunnel experiment is about 6.7%,and the proportion of each part of the indoor heat gain is close,which determines that the wind tunnel measurement is different.The feasibility and accuracy of the SHGC value in the form of shading.Finally,four kinds of sunshade forms of FSS ceiling curtain,built-in louver,photochromic glass film and sky curtain type outdoor awning curtain were selected,and the wind tunnel was used to study the difference of shading performance.The experimental results show that the SHGC values of the four sunshade forms are 0.51,0.44,0.47 and 0.28,respectively.The sunshade performance of the skylight outdoor curtain is obviously better than the other three sunshade forms,and the performance difference of the other three sunshade forms is small.In the proportion of indoor heat gain,the proportion of indoor total radiant heat in the four shade forms is much larger than the proportion of convective heat transfer,which is a key factor affecting the shading performance.According to the experimental results,the skylight-style outdoor ceiling curtain with obvious sunshade performance is preferred.Secondly,considering the indoor human comfort and economic cost,the FSS ceiling curtain is recommended as the inner sunshade solution for the glass lighting roof.In this paper,the wind tunnel is used to study the difference of shading performance when the glass roof is configured with different shading forms.It provides a new idea for the test method of building glass lighting and shading performance.The experimental data obtained are the architectural design workers and related researchers on the roof of building glass.The choice of shading form and the judgment of shading effect provide reference and have certain theoretical and practical significance.