Study On The Effect Of Daily Curtain Adjustment On Building Thermal Performance During Heating Period

Energy-efficiency has received considerable attention in the last decades since the increasingly severe situation of energy supply across the world. The energy consumption in building industry has accounted 30-40% of annual total energy consumption in China. Since enhance the thermo-technical performance of buildings is a promising mean to reduce the total energy consumption and improve occupiers'experiences of thermal comfort, the neglects of thermo-technical performance of building detailed structures in design and operation phases would have significant effects on building operational energy consumption. As people's living quality continues to rise, occupiers require higher thermal comfort experience while the energy-efficiency codes has been satisfied. This paper discusses the effects of window curtain on building thermal performance and thermal comfort based on theoretical, simulative and experimental analysis methods.Firstly, in order to discuss the effects of curtain operation behavior on indoor thermal performance and comfort, the indoor thermal performance and comfort of south and north orientated rooms in radiator heating and radiant floor heating amalgamated dwellings were tested respectively. Based on the test data, the curtain regulation effects on thermal performance under different orientations, heating systems and installation styles were analyzed. For south orientated room, the daily average air temperature was higher when pulled up the curtain during the day and down at night while pulled down the curtain all day for north orientated room. For radiator heating room, the mean radiant temperature could increase 3.0? significantly while only increase 0.85? in radiant floor heating room. The results indicated that it was determined by the insulation performance of curtain and solar irradiance whether the windows was a heat-gain device. Thus, the daily heat balance condition of 12 different combinations of windows and internal curtains were analyzed for severe cold, cold, hot summer and cold winter zones.Moreover, a radiant heat transfer room model was established to analyze the effects of curtain on radiant heat and asymmetry radiant at night based on the field test data. The results demonstrated that the radiant heat between internal surfaces of internal envelope and external windows could reduce 75.5% while 45.4% could be reduce between the body and internal surface of external windows, and the Percentage Dissatisfied (PD) caused by asymmetry radiant could reduce 18.5%.Thus, the internal curtain could reduce the radiant heat-loss through external windows and improve the local thermal comfort.Overall, the BIM models of two actual energy-efficiency buildings were established to study effects of internal curtain on the energy saving rate of whole buildings. For a residential building in severe cold zone, the energy consumption reduced by operations of internal curtain could reach 8.8% in heating seasons and 4.7% yearly while 11.4% reduced in the heating seasons and 9.2% yearly for an office building in cold zoom.Lastly, the heat transfer process of external window installed with internal curtain was analyzed. The results indicated that the insulation of external windows had been significant improved for the air gap formed by pulling down the curtain. The total thermal resistance of single-glazing window could increase 19.8% when pulling down the cotton curtain.It is helpful to optimize the curtain in the future.'The details determine success or failur",to make the buildings fficiency,we should take care of every detail.The study mainly discuss the effect of the curtain adjustment in tradition buildings.It did not cover natural running buildings,on the other hand,the study did not cover the summer case.For vapour barrier,the study main include the use on the project,but the reaction mechanism.So,we should keep trying in studying about these aspects in the future.