| The optimization of energy structure with natural gas as a substitute for coal is an important measure for China to reduce air pollution caused by coal burning in winter.In this context,many new residential buildings in northern China have adopted a natural gas-fueled household intermittent heating model.In southern China,where the differentiated intermittent heating mode is widely used,the “Design Standard for Energy Efficiency of Residential Buildings in South Area of China”(JGJ134-2010)stipulates that in order to reduce heat transfer between rooms,the heat transfer coefficient limits of household walls and floors are not allowed to exceed 2.0 W/m2?K.In contrast,buildings in northern area still use the insulation system that was previously used for centralized heating,and there is no adjustment considering the change of heating mode.In addition,the vacancy rate in the real estate market in China is too high.In order to improve the energy efficiency in winter,it is necessary to focus on how to reduce the heat transfer between neighboring households which use the intermittent heating mode.This paper mainly uses field research,simulation verification and simulation calculation methods to explore the energy-saving effect of insulation of inner enclosure structure.The main work done is as follows:1)Analyze the heat transfer characteristics and energy consumption characteristics of residential buildings which use household heating mode,and study the calculation method of heat transfer between households under the household heating mode,and then propose that to reduce the heat transfer between households,inner insulation structure insulation layer can be set.2)Establish a simplified residential calculation model in the Xi’an area,and study the energy-saving effect of the insulation layer of inner enclosure structure under the condition that the surrounding room has multiple heating conditions.The results show that the insulation layer of the inner envelope structure can significantly reduce the heat transfer between the households and reduce the heat load during the heating period of the room.3)Conduct field research on a residential multi-storey residential building which uses natural-gas boiler as the main heating equipment in Xi’an area,investigate the characteristics of the heating behavior of each household in the building,and use the surveyed information to establish the corresponding building model in the software.Then study the energy-saving effect of insulation of the slab and the partition wall,After that,the number of households using different heating mode,relative positions and proportions of different heating behavior patterns in the surveyed building are changed and transformed to study the energy-saving effect of installing the inner enclosure structure insulation under various conditions.Through the calculation and analysis of the simplified calculation model and a multi-storey building,this paper studies the energy-saving effect of the insulation of the inner envelope structure in the multi-storey residential buildings using intermittent heating mode in Xi’an area.The study indicates that considering the current high housing vacancy rate,laying insulation of inner enclosure structure in the multi-storey residential building with intermittent heating in Xi’an area can provide better energy-saving benefits in terms of building energy consumption.Setting the floor insulation layer can reduce the heating energy consumption of each household,and promote the fairness of the heating energy distribution of each household.At the same time,the calculation method for determining the most economical thickness of the floor insulation layer is also o btained.The research methods and corresponding conclusions used in this paper can provide references for subsequent related researches. |
