Heat recovery from an enhanced geothermal system (EGS) is a complex process involving heat transport in both fracture networks and rock formations. A comprehensive understanding of and the ability to model the underlying heat transport mechanisms is important for the success of EGS commercialization but remains challenging in practice due to the generally insufficient characterization of EGS reservoirs. In the present study, we analyze an extensively monitored intermediate-scale EGS field experiment performed in a well-characterized testbed. The high-resolution, high-quality measurements from the field experiment enable the development of a high-fidelity model incorporating a well-constrained fracture network. Based on the field experiment, we investigate the complex heat transport processes in an EGS-relevant environment and validate the capability of a numerical approach in simulating these inherently coupled heat transport processes. A series of numerical simulations were performed to study the effects of different heat transport mechanisms, including thermal convection with fracture flow, thermal conduction in rock formations, and the Joule-Thomson effect. The agreement of thermal responses between field measurements and simulation results indicates that our numerical approach can appropriately model the heat transport processes pertaining to heat recovery from EGS reservoirs.

增强型地热系统 (EGS) 的热回收是一个复杂的过程，涉及裂缝网络和岩层中的热传输。全面了解和模拟潜在热传输机制的能力对于 EGS 商业化的成功很重要，但由于 EGS 储层的表征普遍不足，因此在实践中仍然具有挑战性。在本研究中，我们分析了在充分表征的试验台中进行的广泛监测的中等规模 EGS 现场实验。来自现场实验的高分辨率、高质量的测量结果能够开发一个包含良好约束的裂缝网络的高保真模型。根据田间试验，我们研究了 EGS 相关环境中复杂的热传递过程，并验证了数值方法在模拟这些固有耦合的热传递过程中的能力。进行了一系列数值模拟以研究不同热传输机制的影响，包括裂缝流的热对流、岩层中的热传导和焦耳-汤姆逊效应。现场测量和模拟结果之间热响应的一致性表明我们的数值方法可以适当地模拟与 EGS 储层热回收有关的热传输过程。包括裂缝流的热对流、岩层中的热传导和焦耳-汤姆逊效应。现场测量和模拟结果之间热响应的一致性表明我们的数值方法可以适当地模拟与 EGS 储层热回收有关的热传输过程。包括裂缝流的热对流、岩层中的热传导和焦耳-汤姆逊效应。现场测量和模拟结果之间热响应的一致性表明我们的数值方法可以适当地模拟与 EGS 储层热回收有关的热传输过程。