Study On Energy Saving Optimization Of Prefabricated Building Envelope Structure In West Sichuan Plain

With the rapid development of economy,the situation of energy shortage in China is becoming more and more obvious.Energy security and energy conservation and emission reduction,especially the research on energy conservation in the construction industry,have become the hot focus of common concern.At present,scholars mainly focus on building energy saving design scheme,structural process and new energy utilization,etc.,building envelope energy saving research is less and the related technical economy,indoor personnel safety and other factors of the study is less concerned.The research of combining it with the prefabricated building to meet the sustainable development is of great significance.The purpose of this study is to supplement the relationship between the attributes of the envelope and the energy consumption of prefabricated buildings,and to make up for the disjunction between energy saving design and project design in the selection of energy saving schemes.In this paper,the prefabricated building in the western Sichuan plain area is taken as the research object,and the energy saving technology measures of the prefabricated building envelope are emphatically studied.In order to further understand the thermal performance of prefabricated building envelope,the production base of prefabricated building and 84 existing assembled buildings in the western Sichuan Plain were investigated,and the survey data were analyzed according to the threshold value of national standards and relevant codes.At present,China’s buildings tend to have large and transparent rooms,and the ratio of Windows and walls in buildings is too large to meet the energy saving standards.In addition,the actual ventilation area available for Windows is too small to meet the indoor human safety.The thermal performance of the building envelope can not meet the regional energy saving standards and green building evaluation standards,and there are few types of energy saving technologies and low application rate.To solve these problems,first of all,the enclosure component samples were selected according to the investigation situation.Secondly,the basic model was established by using Open Studio.The heating and air conditioning load of prefabricated buildings was numerically simulated by taking the thickness of insulation layer,material,structure and window-wall ratio of building exterior wall,roof and window as variables.The analysis shows that under different circumstances,the thickness of the three kinds of insulation materials for the outer wall is XPS-50mm and 80mm respectively.EPS to 60 mm,85 mm;Phenolic/PU-55mm,75mm,respectively:XPS-40mm roof;Phenolic/PU-35mm,40mm.The external Windows are preferred to be coated in accordance with insulating glass,and the safety and comfort of human body are considered.The window-wall ratio of east,south,west and north Windows is limited under the requirements of the code,and the quantitative relationship between variable factors and building energy consumption is fitted.On this basis,univariate multivariate analysis of variance was used to evaluate the correlation between variables.Finally,the mixed level orthogonal test was used to obtain18 optimal energy saving schemes.The first five schemes with significant energy saving effects were compared with the original building energy saving schemes,and the best energy saving scheme A6B2_Best was determined through the benefit evaluation index.In conclusion,the research results and energy saving research ideas of this paper can provide reference for the energy saving technology of prefabricated building envelope in the West Sichuan Plain,and promote the further development of building industrialization in the West Sichuan Plain.