Study On The Indoor Thermal Environment Differentiation Design Of Solar Heating Rural Buildings

Improving the quality of rural residents' living environment is an important content of the construction of a new socialist countryside. Solar energy resources are abundant in Tibet and northwest area in our china. To develop solar heating rural buildings according to the local conditions has a positive effect on improving the indoor thermal environment quality of rural building in winter and resolving the contradiction between rural building heating energy and ecological protection, which is an important measure to realize the sustainable development of rural buildings. The research results have certain guiding significance on the construction and sustainable development of the new socialist countryside.Solar energy is a kind of clean renewable energy, but the energy density of which is not high. Therefore, when solar energy is used as a heating energy for rural buildings in winter, it is difficult to solve the contradiction between supply and demand of building heating energy in winter through passive technology,which has become one of the important problems that restrict the development of solar building.Based on the structural characteristics of rural buildings, the living habits of residents and the indoor thermal conditions in winter in the solar-rich areas, this paper put forward the design method of indoor thermal environment non-uniformity based on indoor space division. The mathematical model and physical model in this paper are established by means of theoretical analysis, experimental measurement and numerical simulation to analyzes the differentiation characteristics of indoor thermal environment in each partition of the building, the characteristics of differentiated indoor thermal environment of solar buildings in different regions are analyzed and compared, and then the solar energy saving structure under indoor space division was optimized analysis. The main results of this paper are as follows:(1) Due to solar radiation has a difference toward orientation, the "outdoor integrated temperature" is taken as the outdoor temperature boundary conditions in this paper while analyzing the indoor thermal environment difference of solar heating rural buildings. This paper calculates the solar radiation and the outdoor temperature of three integrated areas of Lhasa,Yinchuan and Xi'an in winter in different direction. In this paper, we calculated the solar radiation and outdoor integrated temperature in different directions in different areas of Lhasa,Yinchuan and Xi'an in different winter months.(2) The analysis results of the influencing factors of the indoor thermal environment of solar heating rural buildings show that: when the outdoor meteorological parameters and roof thermal parameter are certain, the indoor thermal environment of solar heating rural buildings is mainly affected by the indoor space division, the area ratio of south window to wall, the heat transfer coefficient of exterior wall, the type of external window and the heat transfer coefficient and other factors.(3) Based on the design concept of the matching of room function and indoor space partition, we proposed the building model of non-uniform indoor thermal environment of solar heating rural buildings. According to the winter climate conditions in Lhasa, Yinchuan and Xi'an, We comparative analyzed the effects of three different kinds of indoor space division methods on the main rooms indoor temperature of solar heating rural buildings in Lhasa,Yinchuan and Xi'an.Theoretical analysis and numerical simulation results show that:Reasonable indoor space division methods can significantly improve the indoor temperature of the main rooms of passive solar heating rural buildings, and realize the non-uniform control of indoor temperature field. But by the influence of the difference of the solar radiation intensity and the outdoor air temperature, the temperature increase is different in different regions.(4) We have optimized the energy-saving structure of solar thermal building with differentiation indoor thermal environment, The results show that when the structure is sandwich insulation porous brick wall(the thickness of the porous brick is 290mm, the thickness of the EPS insulation layer is 80mm), the building heating load can be effectively reduced. The heating load of Lhasa reduced the most significant, can be reduced by 40.87%; followed by Xi'an, reduced by 38.74%; the last is Yinchuan, a decrease of 37.45%.(5) The application of phase change material in the solar heating rural building wall can improve the indoor temperature stability at the same time can also significantly at the same time can also significantly. The phase latent heat and phase transformation temperature of phase change material and the number of wall used in the building have an influence on the indoor thermal environment differentiation regulate and control in the building, and there are differences in different regions.Through the study of this paper, we hope to provide a useful theoretical reference for the design theory of the the indoor thermal environment differentiation of the solar heating rural buildings the optimization method of energy saving structure system of building envelope.