地热热泵系统地下换热器的设计长度强烈依赖于钻孔热阻。钻孔热阻由建筑材料的热特性和地下换热器流道的布置来定义，并强烈影响地热热泵系统的性能。通过对地下换热器热阻的数学描述，进行了模拟研究，以检查和比较一些更常见类型的地下换热器的热性能，如单U形管、双U形管、同心管和立柱式井（无地下水排放）。 系统模拟基于短时间步长地下换热器模型，并在考虑小型办公楼的一组等效条件下进行。结果表明，在模拟的条件下，单U形管需要的孔径长度最大。理论上，双U形管、同心管和无泄放的立管井的总钻孔长度分别减少了约22%、33%和36%。考虑到20年的系统运行，还进行了比较生命周期成本分析。单位:双引文:研讨会论文，大西洋城，2002年

The design length of ground heat exchangers for geother-mal heat pump systems is strongly dependent on the borehole thermal resistance. The borehole thermal resistance is defined by the thermal properties of the materials of construction and the arrangement of flow channels of the ground heat exchanger and strongly influences the performance of a geothermal heat pump system. Simulation studies are presented that examine and compare the thermal performance of some of the more common types of ground heat exchangers, such as single U-tube, double U-tube, concentric tube, and standing column well (with no groundwater bleed), using a mathematical description for the thermal resistance of ground heat exchangers. The system simulations are based on a short time step ground heat exchanger model and are conducted under an equivalent set of conditions considering a small office building. Results show that the single U-tube requires the greatest length of bore for the conditions simulated. Theoretical reductions in total bore length of approximately 22%, 33%, and 36% are seen for the double U-tube, the concentric tube, and the standing column well with no bleed, respectively. A comparative life-cycle cost analysis is also conducted considering a 20-year system operation.Units: Dual