Study On The Coupling Characteristics Between Energy Consumption,Indoor Air Quality And Building Airtightness In Residential Buildings

With the rapid improvement of building envelope performance,especially the occurrence of high-performance buildings like nearly zero energy building,relevant studies show that:on one hand,in order to further reduce building energy consumption,it is necessary to greatly avoid the building energy consumption generated by air infiltration;on the other hand,with the improvement of building airtightness the indoor air quality under certain conditions is decreased.Therefore,domestic scholars have doubts about whether residential buildings should continue to reach ultra-high airtightness.Furthermore,under the limitation of indoor air quality and building energy consumption,how to put forward the requirements of building airtightness becomes a problem to be solved urgently.Through the research on the relationship between building airtightness,building energy consumption and indoor air quality at home and abroad,the main factors affecting the relationship were determined.The coupling relationship between the airtightness,building energy consumption and indoor air quality under different indoor and outdoor temperature differences in typical climate regions is studied,and the method to determine the building airtightness design value in different regions is proposed.The main results are as follows:（1）Through the Energy Plus model and the existing particle penetration model,it is confirmed that building airtightness has a significant impact on indoor air quality and building energy consumption.In terms of different regions,the proportion of energy consumption caused by air infiltration in the total energy consumption is significantly higher in severe cold regions than that in other regions;The difference of energy consumption caused by air infiltration in winter is significantly higher than that in summer.（2）With the help of the“Future Lab”experimental platform,we completed the experimental research on the relationship between the building energy consumption and main indoor pollutants including CO₂,TVOC and PM2.5 under four indoor and outdoor temperature differences and five building airtightness levels.Based on the experimental data,the relationship between building air tightness,building energy consumption,CO₂and TVOC was determined under different indoor and outdoor temperature differences in different regions.（3）By analyzing the coupling effect between N₅₀,indoor air quality and energy consumption caused by air infiltration,this paper puts forward a method to determine the best balance point of building airtightness in residential buildings without fresh air system,which plays a theoretical support role in the coupling research of building air tightness,indoor air quality and other factors in residential buildings.（4）According to the method proposed,the recommended values of building airtightness design in main cities of each climate zone are put forward.The results show that the equilibrium points of Harbin,Beijing,Shanghai and Guangzhou are0.97、1.94、2.51 and 4.37 h^-1respectively.In this study,the coupling relationship between building air tightness,building energy consumption and indoor air quality is studied by experimental research method,which promotes the design of building airtightness changing from single factor to coupling factors.It also provides a scientific method for the airtightness design in residential buildings.