Theoretical And Experimental Research On Energy Performance Of Window Glass With Solar-Control Film

Building energy consumption accounts for more than a quarter of total energy consumption in China. Window is a weak part in building envelope. Air conditioning energy consumption caused by window accounts for a sizeable proportion in the whole building energy consumption. So reducing energy consumption through windows is a very effective way to cut down building energy consumption. Solar-control coated glass and low-E coated glass can greatly reduce the heat through the windows, thus reduce air conditioning load. Therefore, it is very important to research and utilize these special glazing to decrease building energy consumption.The heat conductive model of single coated glass is set up. Bouguer formula is used to calculate direct solar radiation and Berlage formula is used to calculate diffuse solar radiation. The simple monolithic model is deduced to calculate the solar optical properties of coated glass. The energy performance of solar-control film on single window glass is theoretically analyzed. The methods are given to calculate the whole heat transfer from outside environment to inside through the windows with or without film.In order to verify the energy-saving effect of solar-control film glass, an experiment was carried out in one hotel of Xiangtan. The goal of the experiment is to compare the energy consumption and daylight illumination of two air-conditioned hotel guest rooms with and without solar-control film on single window glass. The experiment results show that the room with film can save energy expenditure 0.51kW.h compared with the room without film in sunny summer, but consume 0.89kW.h more energy expenditure in sunny winter. The room with film doesn't consume more electric lighting energy in sunny or rainy weather. The theoretical analysis result and the experiment result are compared, and it shows that the theoretical analysis result and experimental result have a good agreement in the energy saved by solar-control film. The theoretical analysis and experimental results also show that the solar-control film can get good energy-saving effect in the area where the solar radiation is intensive in summer, and the air conditioning time is longer the heating time.Software Optics5.0 and Window5.0 are used to simulate the energy performance of single glazing, double glazing, single low-E glazing and double low-E glazing. The overall energy flow due to indoor-outdoor temperature and the solar radiation through the glazing are calculated in the building toward different directions.The conclusion has important reference value for glass users, design engineers and research workers in the construction industry.