Energy Saving Research Of Windows In School Buildings Considering Daylighting And Thermal Performance

Energy conservation in building area is an essential issue for achieving sustainable environment.However,building experienced significant amount of heat gain or loss through window and this will affect the thermal comfort of buildings' occupants.The paper investigates the extent to which the implementation of certain interventions to the building envelope of existing schools,can improve their energy performance and at the same time ensure thermal and visual comfort.Nevertheless,apparent sizing contradictions occur when minimizing energy consumption(smaller window sizes)but maximizing visual aspects(larger window sizes).It is also believed that natural lighting has affected the design of school buildings more than any other building type while the main problem is located on quality rather than on quantity issues.The present study focuses on investigating the energy saving of classroom when daylighting and artificial light are integrated while maintaining visual comfort.This paper comprehensively summarized the research status of daylighting.Through the analysis of the research,the process and the calculation model of indoor environment have been proposed.Based on the analysis of the study,four influencing factors of the area,shape,orientation and shading of the window were put forward,and the single factor analysis was carried out.Thus,the influence of solar radiation on the load,heat and total load were simulated under typical winter,summer and transitional season climatic conditions,combining Energy plus software simulation and theoretical calculation.According to the obvious contradiction between the indoor lighting and the heat gain in the summer,the orthogonal experiment was designed to simulate the 16 kinds of simulation schemes in the model,and the influence of the different factors on the indoor load is evaluated quantitatively to determine the optimal configuration scheme.Then,the study presented the use of an evaluation index to assess the optimal trade-off between minimizing load of heating and lighting,reducing summer discomfort time and maximizing the Useful Daylight Illuminance(UDIavg,between 100 and 2000 lx).The evaluation index was discussed combining with different control strategies.Through the establishment of the evaluation index U,the comprehensive evaluation of different control methods can be used to guide the indoor environment operation.What's more,the results of energy saving analysis show that the indoor load is reduced by 77.65%,the average indoor temperature is reduced by 4.50? and the indoor light environment UDI is increased by 2.95% after the control strategy was adopted in summer.The effectiveness of the control strategies was proved to be effective.Finally,the paper carried on the forecast to the follow-up studies.