| Today a large amount of energy is used for space conditioning, which accounts for about 30% of annual energy consumption. Ground source heat pump (GSHP) systems are one of the most energy –efficient, environmentally clean, and cost-effective space conditioning systems available today. In our country, it is a kind of main climate from hot-in-summer and cold-in-winter. The day of refrigeration and heat supply is less than two hundred days in one year in this areas. Wuhan areas belongs to this kind of climate typical, because of its abominable weather and building hot environmental state, strongly need one energy-conservation, clean, operating steady heat system to solve heat supply and refrigeration problem. Therefore, the GSHP can be used in hot-in-summer and cold-in-winter zone as to its systematic characteristic. The subject combines study on GSHP. Vertical U-tube heat exchangers are the most widely used heat exchangers for large GSHP systems. U-tube heat exchangers experience thermal interference (or thermal short circuiting) between the two adjacent legs due to asymmetric boundary conditions in a non-homogeneous medium. Large GSHP systems may use dozens of U-tube heat exchangers in a multiple borehole field where thermal interference from adjacent boreholes affects long-term performance. A finite element numerical model was used to analyze various borehole configurations, field geometric configurations and to make parametric analyses with source temperature, nonhomogeneous properties, borehole size, soil thermal conductivity, and separation distance between pipes. Finally, the ANSYS software was used to analyze the thermal effectiveness on soil thermal conductivity, separation distance between pipes, borehole size, and source temperature, etc, those can offer design and reference for Wuhan area actually for using GSHP systems.
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