Heat Transfer Analysis Of Buried Pipes Underground Seasonal Thermal Storage

In view of the northern cold regions, winter heating for a long time,summer air time is short, resulting in ground source heat pump system underground cooling and heating load imbalance is proposed based on the underground pipe solar seasonal storage method, the ground heat heat transfer and its influencing factors are analyzed. The results showed that:In cold areas, the use of ground heat for solar thermal storage is conducive to long-term effective operation of ground source heat pump.Established the ground heat storage underground cross-quarter physics and mathematical model of heat transfer by numerical simulation method to simulate the ground heat exchanger underground temperature field analysis of buried pipe spacing, soil thermal properties and other major factors the impact of ground heat exchanger, heat storage characteristics of the soil.A single group of underground pipe and underground pipe were simulated and analyzed, discussed the distance between the pipe, ground heat circulating fluid velocity and temperature effects on the underground temperature field and the use of solar energy-shallow geothermal complex test-bed for air conditioning systems experimental research and numerical simulation results validate. Obtained the following main results:(1) ground heat transfer model and numerical simulation results and experimental results are compared both in the regenerative process of the ground heat circulating fluid inlet and outlet temperature trends and the value less the same.(2) carried out in winter and summer Numerical simulation of two conditions, the underground temperature distribution that cold regions is much larger than the thermal load cooling load, the use of ground source heat pump system to pipe for solar thermal storage, enabling underground temperature field be effectively restored, is conducive to underground hot load balancing.(3) to pipe spacing influence on the thermal efficiency. When the pipe spacing of5m, the summer heat and winter storage heat much better than taking the case spacing of3m By appropriately increasing the buried pipe spacing, to improve the heat transfer per meter drilled holes to appropriately reduce the number of purposes.(4) ground heat pipe circulating fluid flow rate is not too large. Flow rate is too large, the heat storage capacity of soil to improve slightly, but the resulting energy consumption of a large increase in circulating pump. More appropriate velocity range0.4-0.6m.