Many researchers numerically investigated U-tube underground heat exchanger using a two-dimensional simplified pipe. However, a simplified model results in large errors compared to the data from construction sites. This research is carried out using a three-dimensional full-size model. A model validation is conducted by comparing with experimental data in summer. This article investigates the effects of fluid velocity and buried depth on the heat exchange rate in a vertical U-tube underground heat exchanger based on fluid–structure coupled simulations. Compared with the results at a flow rate of 0.4 m/s, the results of this research show that the heat transfer per buried depth at 1.0 m/s increases by 123.34%. With the increase of the buried depth from 80 to 140 m, the heat transfer per unit depth decreases by 9.72%.

中文翻译：

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埋深对立式U型管埋地换热器热性能的影响

许多研究人员使用二维简化管道对 U 型管地下换热器进行了数值研究。然而，与建筑工地的数据相比，简化的模型会导致较大的误差。这项研究是使用三维全尺寸模型进行的。通过与夏季的实验数据进行比较，进行模型验证。本文基于流固耦合模拟研究了流体速度和埋藏深度对立式 U 型管地下换热器热交换率的影响。与0.4 m/s流速下的结果相比，本研究结果表明，1.0 m/s时单位埋深的传热增加了123.34%。随着埋深从80m增加到140m，单位深度的传热量下降了9.72%。