Probe On Intermittent Solar Hot Air Self-heating Of Village Buildings In Severe Cold Area

In severe cold area, there are many problems in rural buildings with heated kang,such as bad smoke extraction, low indoor temperature in winter, serious indoor air pollution,and so on. In this paper, a system based on solar energy and shadow earth energy has been put forward in rural buildings of cold regions. We use solar energy to promote indoor air temperature in winter and use earth air tunnel heat exchanger to preheat or precool the outdoor air in order to improve the quality of indoor air.An intermittent natural vention system of solar hot air is going to be proposed for rural buildings with heated kang in cold regions. This syetem takes full advantages of hot pressing of solar radiation to realize natural vention for improving indoor thermal comfort, and this system also uses a combination of the technology of earth air tunnel heat exchanging, waste heat recovery of heated kang, natural circulation of refrigerant, and so on.We use the technology of CFD and its corresponding softwares to carry through simulation calculation, by establishing a three-dimensional model and meshing. Many factors affecting the intermittent natural vention system of solar hot air, including solar radiation intensity, the area of solar heating wall, the thickness of the thermal channel, the size of inlet and outlet, absorbing coating characteristics, the outer cover and so on, will be studied by means of steady numerical simulation techniques. Based on the above studied parameters, a transient simulation model is built to study the intermittent natural vention system of solar hot air and the best opening and closing time of this syestm in cold regions is proposed in winter.The technology of earth air tunnel heat exchanging is studied in cold regions by numerical simulation techniques.The factors affecting the earth air tunnel heat exchanging includes the length of the buried pipe, the depth of the buried pipe, the diameter of the buried pipe, the inlet velocity of the buried pipe, the types of the buried pipe, and so on.In this paper, the intermittent natural vention system of solar hot air is analysed in detail. The operation of the intermittent natural vention system of solar hot air and the earth air tunnel heat exchanging techniques is studied respectively, providing a good reference for using them in cold regions.This paper’s topic is a part of the project`The Key Technologies of Intermittent Self-heating and Foam Concrete Materials Suitable for Green Village Buildings in Severe Cold Area`,which is the national`12th Five-Year Plan`to support science and technology project(No.2013BAJ12B03).