Energy-saving Design Of Rural Low-energy Residential Buildings In Qinghai-Tibet Plateau

Through its unique geographical location,low-energy residential buildings in rural areas of Qinghai-Tibet Plateau can obtain abundant solar energy resources to achieve the purpose of building energy conservation.At the same time,it can improve the utilization rate of rural resources and energy resources in the region,optimize and improve the links of various links in the building construction process,form a complete energy-saving construction system,and reduce unnecessary waste.Therefore,it has certain theoretical significance and practical application value to study the energy saving of its envelope structure.This paper takes the rural houses in the Qinghai-Tibet Plateau as the research object,and focuses on the energy-saving design of the external protective structure in rural low-energy residential buildings in the region.Through on-the-spot investigation of 100 farm houses,it was found that the brick-concrete structure accounted for 95%,the 370mm red brick exterior wall accounted for 95%,the aluminum alloy outer window accounted for 75%,and the laminated floor occupied 100%.In addition,the outer wall was self-insulated.The thickness is thicker;the heat transfer coefficient of the outer window is too high,and the airtightness is poor;the thermal performance of the roof is poor;the ground is not insulated;Can not meet the requirements of《Environmental Design Standards for Rural Residential Buildings》GB/T 50825-2013.Therefore,it is necessary to improve energy-saving improvements in the rural residential exterior structure.According to the investigation and analysis,it is concluded that the outer wall adds insulation layer to form the thermal insulation outer wall;the roof surface selects the thermal insulation roof of high-efficiency thermal insulation material;the outer window selects the window frame material and the glass type improvement measures with excellent thermal insulation and thermal insulation performance.In order to further analyze the influence factors of energy consumption on the envelope structure of low-energy residential buildings in rural areas,energy-saving schemes with different insulation materials and different thickness of insulation layer are proposed in this paper.When XPS,EPS and phenolic aldehyde are used as insulation materials for external walls,the thickness of insulation layer should be 70-80mm;when XPS,EPS and PUR are used as insulation materials for roofs,the thickness of insulation layer should be 160-180mm is suitable;plastic steel + Low-E coated hollow glass is preferred for outer windows.Under the premise of ensuring ventilation and lighting,the ratio of window to wall should be increased appropriately in the south,East and West directions.In order to verify the energy-saving scheme and energy-saving efficiency proposed in this paper,taking the Tu er gan Area of Qinghai-Tibet Plateau as an example,four overall energy-saving optimization schemes of A~D proposed are compared with the original scheme by simulation calculation.It is concluded that with the decrease of heat transfer coefficients of exterior walls,roofs and windows,their annual cumulative heat loads are also reduced.The annual cumulative energy-saving rate of the optimized scheme is about 40%,31%,35%and 45%.Among them,the D scheme has the best energy-saving efficiency and can meet the requirements of heating and refrigeration energy consumption for low-energy residential buildings.In summary,the research in this paper can provide guidance and suggestions for the energy-saving design of low-energy residential buildings in the Qinghai-Tibet Plateau,and promote the development of low-energy rural houses in China.