With their high storage capacity and energy efficiency as well as the compatibilities with renewable energy sources, high-temperature aquifer thermal energy storage (HT-ATES) systems are frequently the target today in the design of temporally and spatially balanced and continuous energy supply systems. The inherent density-driven buoyancy flow is of greater importance with HT-ATES, which may lead to a lower thermal recovery efficiency than conventional low-temperature ATES. In this study, the governing equations for HT-ATES considering buoyancy flow are nondimensionalized, and four key dimensionless parameters regarding thermal recovery efficiency are determined. Then, using numerical simulations, recovery efficiency for a sweep of the key dimensionless parameters for multiple cycles and storage volumes is examined. Ranges of the key dimensionless parameters for the three displacement regimes, that is, a buoyancy-dominated regime, a conduction-dominated regime, and a transition regime, are identified. In the buoyancy-dominated regime, recovery efficiency is mainly correlated to the ratio between the Rayleigh number and the Peclet number. In the conduction-dominated regime, recovery efficiency is mainly correlated to the product of a material-related parameter and the Peclet number. Multivariable regression functions are provided to estimate recovery efficiency using the dimensionless parameters. The recovery efficiency estimated by the regression function shows good agreement with the simulation results. Additionally, well screen designs for optimizing recovery efficiency at various degrees of intensity of buoyancy flow are investigated. The findings of this study can be used for a quick assessment and characterization of the potential HT-ATES systems based on the geological and operational parameters.

中文翻译：

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考虑浮力流的高温含水层储热蓄能采收效率估算


高温含水层热能储存 （HT-ATES） 系统具有高存储容量和能源效率以及与可再生能源的兼容性，是当今设计和空间平衡和连续能源供应系统设计的目标。HT-ATES 固有的密度驱动浮力流更为重要，这可能导致比传统低温 ATES 更低的热回收效率。在本研究中，考虑浮力流的 HT-ATES 控制方程是无量纲的，并确定了有关热回收效率的四个关键无量纲参数。然后，使用数值模拟，检查了多个周期和存储量的关键无量纲参数扫描的恢复效率。确定了三种位移状态的关键无量纲参数的范围，即浮力主导状态、传导主导状态和过渡状态。在浮力主导的范围内，采收效率主要与 Rayleigh 数和 Peclet 数之间的比率相关。在传导主导的范围内，回收效率主要与材料相关参数和 Peclet 数的乘积相关。提供了多变量回归函数，以使用无量纲参数估计恢复效率。由回归函数估计的回收效率与仿真结果具有良好的一致性。此外，还研究了在不同程度的浮力流强度下优化采收效率的井筛设计。 本研究的结果可用于根据地质和操作参数快速评估和表征潜在的 HT-ATES 系统。