Research Of Solar Hot Air Soil Heat Storage Heating System In Sheep Pen In Cold Area

Animal husbandry is mainly distributed in the north of China.The climate of cold area is bad in winter,which is very harmful to the growth of livestock.It is necessary to use the active heating technology to improve the indoor temperature of the pen in winter.This paper introduces the system structure and working principle of solar hot air heat storage heating system in detail.On this basis,the mathematical models of twostage transpired collector and earth-to-air heat exchanger are established.In order to explore the application effect of the system in animal husbandry in cold area,this paper applies it to a sheep pen in Damaoqi,Inner Mongolia.According to the theoretical model,using MATLAB software to calculate the annual hourly value of the hot air at the outlet of the collector.This paper analyzes the thermo physical properties of soil and the influencing factors of the performance of soil air heat exchanger.The three-dimensional transient models of earth-to-air heat exchanger.Use FLUENT to establish the three-dimensional transient model of the earth-to-air heat exchanger and the sheep pen,and simulate the performance of the system in the heat storage period and heating period respectively.The results show that the temperature of the hot air at the outlet of the collector is above 30? most of the time,and the temperature rise of the air of the collector is above 25?.Even in the coldest month,the hot air temperature can meet the indoor heating demand.The heat storage period of the system is 4 months(June 1?September 21).At the end of the heat storage period,the soil temperature is 41.9?,and the total temperature is increased to 26.9?;the heating period is 7 months in total,except that the indoor temperature cannot reach 10? from late January to late March,the indoor temperature and the heat exchange efficiency of the system can meet the expected requirements in other time,and the system operates well.Finally,the improvement measures of system performance are improved.The solar hot air heat storage heating system combines the solar collector with the earth-to-air heat exchanger,uses the seasonal soil heat storage.The system stores heat in summer and heats the room in winter,at the same time,it can be bring fresh air into the room to improve the indoor air environment.The system has the advantages of low initial investment,long service life,simple maintenance and great application prospect.