Abstract A new cylindrical model is proposed, suitable to determine both the short-term and the long-term fluid-to-ground thermal response factor of a single U-tube borehole heat exchanger (BHE). In the model, a BHE is represented by an equivalent cylinder, with the same radius and heat capacity as the BHE. The cylinder is made of a homogeneous material and contains a heat-generating cylindrical surface with an equivalent radius, req, optimized by repeated 2D finite-element simulations. The thermal resistance of the layer between req and the BHE radius equals the BHE thermal resistance. A correlation yielding the optimized values of req is provided.

中文翻译：

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一种单一材料圆柱模型，用于确定单 U 型管埋管换热器的短期和长期流体对地响应因子

摘要 提出了一种新的圆柱模型，适用于确定单个U型管埋管换热器（BHE）的短期和长期流体对地热响应因子。在模型中，BHE 由等效圆柱体表示，具有与 BHE 相同的半径和热容。圆柱体由均质材料制成，并包含具有等效半径 req 的发热圆柱表面，通过重复的 2D 有限元模拟进行优化。req 和 BHE 半径之间的层的热阻等于 BHE 热阻。提供了产生 req 优化值的相关性。