The Energy Consumption Simulation Of The Existing Office Buildings With Glass Film

With the continuous development of economy in China,building energy consumption is increasing.People’s requirements for the indoor environment of buildings have also been continuously improved.Without reconstruction,A large number of existing office buildings were built early and cannot satisfy the requirements of energy saving and comfort.In the glass film market,there are many types,but specific conditions and effects are not clear.Based on this background,this paper uses the literature research method and simulation method to study the glass film technology for existing office buildings.Determining the energy-saving properties of general film and solar control film in single-layer glass and double-layer insulating glazing system will come true.It would clarify the adaptability and economics in different orientations for four climatic zones with glass film.Finally,it puts up the concept of the coefficient of correction using glass film.First of all,based on statistical data and yearbooks,the energy consumption and energysaving reconstruction projects of office buildings in Shanghai,Shenzhen,and Chongqing in recent years were studied.It’s found that glass systems were the key in energy-saving reconstruction.The energy saving data of specific cases show that glass film is a great measure with high energy saving rate and low investment payback period in Shanghai and Shenzhen.At present,the model of glazing with film is not acknowledged uniformly.The Lawrence Berkeley National Laboratory(LBNL)uses the optical internal radiation model to calculate the single-layer film glass and reassembles the hollow glazing with film system.The optics and heat transfer are determined by the U-factor and solar heat gain coefficient(SHGC coefficient).The Mexican team takes the hollow glazing with film as a whole model and directly calculates the temperature and heat transfer of the glazing system.The two methods are quite different.Since the LBNL series of algorithms has developed a series of building simulation software and the calculation is relatively stable,this article chooses the LBNL series of algorithms.Then,through Optics6 and WINDOW7.5 software,the blank group and the film group were simulated and calculated respectively.The optical parameters of the glazing with film are calculated by Optics6.In single-layer and hollow glazing systems with film,the transmittance of visible light decreases,while the front and back reflectance increase.Input the optical parameters into WINDOW7.5,and calculate the windows value with the glass film.Compared with the blank group,the thermal parameters of the window,except for the single-layer glazing with general film indoor,have a little effect on the U-factor after the film is applied,but have a great impact on the SHGC and VT coefficients.Finally,Energy Plus was used to simulate the building energy consumption.Representative cities were selected in 4 different climatic regions,and the basic geometric model of the office building was established.The parameters of glazing with films in WINDOW7.5 were used as variables,and the simulation parameters were set for calculation.The calculation results show that the energy saving effect of the single-layer glazing system using film is obvious,and the annual energy consumption is significantly reduced.In the double-layer insulating glazing system,the economic effect of the film is not obvious in Harbin,Tianjin and Shanghai.The energy consumption in Shenzhen is significantly reduced,and the effect of the solar control film is better.It is not suitable to use the film in south orientation in severe cold area.And in the other three climate zones,all oriented window should use the applied film because of the high energy-saving rates.Through the design of cold load in summer,the concept of correction factor of glass film is put forward for existing building energy-saving reconstruction projects.