Geothermics最新文献_第5页

Construction of a medium-deep geothermal storage system: Case study of the SKEWS MD-BTES demosite 中深层地热储热系统的建设：以SKEWS MD-BTES花岗岩为例

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-18 DOI: 10.1016/j.geothermics.2025.103579

Matthias Krusemark , Lukas Seib , Hung Pham , Ingo Sass

The global energy transition toward renewable resources poses particular challenges in the heating sector, where a seasonal mismatch between heat demand and supply remains a critical obstacle. Medium-deep borehole thermal energy storage systems (MD-BTES), installed at depths of 400–1000 m, offer large subsurface storage capacities while avoiding the high costs associated with deep geothermal drilling. To date, the benefits of MD-BTES have been demonstrated primarily through modelling studies, with limited empirical validation. Here, we report the construction and commissioning of the first MD-BTES demonstration site at the Lichtwiese Campus in Darmstadt, Germany. In 2022–2023, three 750 m deep borehole heat exchangers (BHE) were installed in a triangular layout with 8.6 m spacing. When expanded to 37 BHE, with inlet temperatures of 90 °C (summer) and 30 °C (winter), output up to 15 GWh·a^-1 and 3.5 MW is achievable with a recovery efficiency up to 75 % after 5 years of operation. During drilling, unforeseen (hydro-)geological conditions, including fault zones and extensively altered crystalline rocks, required a transition from pneumatic and hydraulic down-the-hole hammer drilling to rotary drilling with clay-polymer fluids. Comparative analysis showed that the pneumatic and hydraulic hammer techniques achieved 2 to 5 times higher rates of penetration relative to rotary drilling. Continuous groundwater monitoring revealed a temporary ecological impact from drilling fluids and intermediate cementations, which dissipated after completion. The drilling operations consumed ∼90,950 L of diesel fuel, corresponding to ∼244 t CO₂ emissions.

These results provide, for the first time, a comprehensive empirical assessment of MD-BTES construction under practical field conditions, enable extended test operations on storage efficiency, and highlighting the need for economically viable vertical and fast drilling technologies for large-scale MD-BTES development.

全球能源向可再生资源的转型给供热行业带来了特别的挑战，供热需求和供应之间的季节性不匹配仍然是一个关键障碍。中深钻孔热能存储系统（MD-BTES）安装在400-1000米的深度，提供了大的地下存储容量，同时避免了与深层地热钻井相关的高成本。迄今为止，MD-BTES的好处主要是通过建模研究证明的，经验验证有限。在这里，我们报告了在德国达姆施塔特的lictwese校区的第一个MD-BTES示范点的建设和调试。在2022-2023年，三个750 m深的井眼热交换器（BHE）以三角形布局安装，间距为8.6 m。当扩展到37 BHE，进口温度为90°C（夏季）和30°C（冬季）时，运行5年后，输出可达15 GWh·a-1和3.5 MW，回收效率高达75%。在钻井过程中，不可预见的（水力）地质条件，包括断层带和广泛改变的结晶岩，需要从气动和液压井下锤式钻井过渡到粘土聚合物流体的旋转钻井。对比分析表明，气动和液压锤技术的钻速是旋转钻井的2 ~ 5倍。连续的地下水监测显示，钻井液和中间胶结物对生态造成了暂时的影响，这些影响在完井后消散。钻井作业消耗了约90950升柴油，相当于排放了约244吨二氧化碳。这些结果首次在实际油田条件下对MD-BTES施工进行了全面的经验评估，实现了对存储效率的扩展测试操作，并强调了大规模MD-BTES开发对经济上可行的垂直和快速钻井技术的需求。

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引用次数: 0

Characterizing hydraulic properties of the Upper Jurassic aquifer in Southeast Germany using simulated pumping tests of a complex multiwell geothermal site 利用复杂多井地热场模拟抽水试验表征德国东南部上侏罗统含水层水力特性

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-18 DOI: 10.1016/j.geothermics.2025.103566

Mohamed Morsi , Florian Konrad , Kai Zosseder

Precise characterization of a reservoir's hydraulic properties is crucial for the efficient utilization of deep geothermal resources. However, this task becomes particularly challenging in reservoirs with high heterogeneity, as such conditions complicate the parameterization of numerical models, which are key exploration components. Nevertheless, introducing such spatial intricacy to a model often leads to increased accuracy and enhanced predictive capabilities. To effectively represent these complex systems, numerical models must reliably emulate natural reservoir behavior. Among effective modeling techniques, pumping tests are particularly important for their capability to explain groundwater flow dynamics near geothermal wells. At multiwell sites, integrating data from interference tests enables the investigation of the reservoir far-field, leading to a better understanding of the reservoir characteristics, interwell communication, and overall flow conditions. In this study, a multiwell site operates in a highly heterogeneous reservoir comprising two major fault zones that divide the reservoir into three blocks, as well as multiple influx zones, including a karst zone, debris facies, and porous matrix. This research aims to identify the hydraulic role of each reservoir component through developing a highly detailed numerical model that can reproduce the wells’ interactions during pumping tests. This also includes ranking the importance of each reservoir component on groundwater flow using a robust sensitivity analysis. Influx zones in the middle and bottom blocks were found to exhibit the strongest impact on the reservoir’s fluid dynamics. Karst zones, in particular, were also crucial to accurately capture the interactions between the neighboring wells, whereas fault zones diminish cross-fault interferences.

储层水力特性的准确表征对于深部地热资源的有效利用至关重要。然而，在非均质性高的油藏中，这一任务变得尤其具有挑战性，因为这种条件使数值模型的参数化复杂化，而数值模型是勘探的关键组成部分。然而，将这种空间复杂性引入模型通常会提高准确性和增强预测能力。为了有效地描述这些复杂的系统，数值模型必须可靠地模拟储层的自然行为。在有效的建模技术中，抽水试验尤其重要，因为它能够解释地热井附近的地下水流动动力学。在多井现场，整合干扰测试数据可以对储层进行远场调查，从而更好地了解储层特征、井间通信和整体流动状况。在本研究中，一个多井场在一个高度非均质油藏中作业，该油藏包括两个主要断裂带，将油藏划分为三个区块，以及多个流入带，包括喀斯特带、碎屑相和多孔基质。本研究旨在通过开发一个非常详细的数值模型来确定每个储层组成部分的水力作用，该模型可以重现泵送测试期间油井的相互作用。这还包括使用稳健的敏感性分析对每个水库组成部分对地下水流动的重要性进行排序。发现中部和底部区块的流入区对储层流体动力学的影响最大。岩溶带对于准确捕捉相邻井之间的相互作用也至关重要，而断层带则减少了断层间的干扰。

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引用次数: 0

Demand, operational conditions, and impacts on geothermal energy networks 需求、运行条件和对地热能网络的影响

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-17 DOI: 10.1016/j.geothermics.2025.103574

Nicholas Fry, Roman Shor, Aggrey Mwesigye

This study extends a previously established System Dynamics (SD) geothermal energy network (GEN) modeling framework to evaluate how regional thermal demand, auxiliary equipment strategies, and operational conditions influence GEN performance across varied climatic settings, therefore influencing market viability. Using thermal load profiles from ResStock and ComStock for multifamily and medium office buildings in Washington, Illinois, and New York, the study simulates GEN behavior with configurations including single-source borehole heat exchangers, passive cooling, dry cooler hybridization, and waste heat injection to the ground heat exchangers. The SD model captures nonlinear feedback between seasonal demand patterns, auxiliary system activation, and formation thermal conductivities, enabling scenario-based sensitivity analyses with grid searches using control regimes. Results indicate that both climatic conditions and operational controls have measurable impacts on system performance, system longevity, auxiliary equipment cycling, and electricity consumption. The findings suggest that tailored GEN configurations, responsive to regional thermal conditions, can mitigate oversizing, reduce parasitic loads, and enhance techno-economic outcomes. These tailored solutions are, however, not complicated to envision and the study findings suggest there is little need for perfecting borehole heat exchanger sizing. Wide scale adoption can occur now using simple operational strategies to stabilize year-over-year costs. Limitations in site-specific data are apparent, but the regional insights provided offer valuable guidance for engineers, geoscientists, and policymakers engaged in GEN deployment. This work underscores the importance of feedback-oriented modeling to anticipate the thermal behaviors of GENs and to inform infrastructure investment decisions in the context of decarbonization mandates.

本研究扩展了先前建立的系统动力学（SD）地热能源网络（GEN）建模框架，以评估区域热需求、辅助设备策略和运行条件如何影响不同气候环境下的地热能源网络性能，从而影响市场可行性。利用ResStock和ComStock提供的华盛顿、伊利诺斯州和纽约多户和中型办公大楼的热负荷数据，该研究模拟了包括单源井内热交换器、被动冷却、干式冷却器混合和向地面热交换器注入废热等配置的GEN行为。SD模型捕获了季节性需求模式、辅助系统激活和地层热导率之间的非线性反馈，实现了基于场景的敏感性分析，并使用控制机制进行网格搜索。结果表明，气候条件和操作控制对系统性能、系统寿命、辅助设备循环和电力消耗都有可测量的影响。研究结果表明，根据区域热条件量身定制的GEN配置可以缓解超大规模，减少寄生负荷，并提高技术经济效益。然而，这些量身定制的解决方案并不复杂，研究结果表明，几乎没有必要完善井眼热交换器的尺寸。现在可以使用简单的操作策略来稳定年度成本，从而实现大规模采用。特定地点数据的局限性是显而易见的，但区域洞察为参与GEN部署的工程师、地球科学家和政策制定者提供了有价值的指导。这项工作强调了以反馈为导向的建模的重要性，以预测GENs的热行为，并在脱碳授权的背景下为基础设施投资决策提供信息。

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引用次数: 0

Fluid flow and heat transfer during staged multi-cluster fracturing treatments along horizontal wells — Application for hydraulic fracture characterization using distributed temperature sensing 水平井分段多簇压裂过程中的流体流动和热传递。分布式温度传感在水力裂缝表征中的应用

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-16 DOI: 10.1016/j.geothermics.2025.103570

Cao Wei , Dan Qu , Haitao Li , Shiqing Cheng , Chang Liu , Hassan Hassanzadeh

We present a technique for quantitatively characterizing fracture parameters during fracturing operation using temperature information recorded by distributed temperature sensing (DTS). A coupled thermo-hydraulic forward model is first developed to describe the fluid flow and heat transfer in the wellbore, fracture, and reservoir. The developed model is solved using the finite-difference approach for both injection and shut-in periods of staged multi-cluster fracturing treatments along horizontal wells. Then, the DTS temperature behavior is studied by conducting a sensitivity analysis of essential parameters. The results show that temperature signals capture changes in the fracture, reservoir, wellbore, and operation parameters, demonstrating DTS temperature data's feasibility in diagnosing fracture properties. The results also indicate that the temperature response at fracture locations shows a V-shape characteristic for both injection and shut-in periods, aiding in identifying the locations of the created fractures. The proposed model integrated with the Genetic Algorithm is applied to interpret DTS data from a shale gas reservoir, providing parameters like injection volume, fracture locations, fracture half-length, and leak-off coefficient at one particular time. These results enhance new insights on utilizing temperature data for fracturing optimization and further improve energy extraction performance from the stimulated reservoirs.

我们提出了一种利用分布式温度传感（DTS）记录的温度信息定量表征压裂作业中裂缝参数的技术。首先建立了一个热-液耦合正演模型来描述井筒、裂缝和储层中的流体流动和传热。利用有限差分方法求解了水平井分段多簇压裂注入和关井阶段的模型。然后，通过对关键参数的灵敏度分析，研究了DTS的温度行为。结果表明，温度信号捕获了裂缝、储层、井筒和作业参数的变化，证明了DTS温度数据在诊断裂缝性质方面的可行性。结果还表明，在注入和关井期间，裂缝位置的温度响应都呈现v型特征，有助于识别新裂缝的位置。该模型与遗传算法相结合，用于解释页岩气储层的DTS数据，提供特定时间的注入量、裂缝位置、裂缝半长和泄漏系数等参数。这些结果为利用温度数据进行压裂优化提供了新的见解，并进一步提高了增产储层的能量提取性能。

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引用次数: 0

Evaluation of the use of a thermal dynamic probing light (T-DPL) for the field determination of soil thermal conductivity 热动态探测光（T-DPL）在土壤热导率野外测定中的应用评价

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-16 DOI: 10.1016/j.geothermics.2025.103572

João Luiz Botega Nogari, Cristina de Hollanda Cavalcanti Tsuha

The soil thermal conductivity governs the heat transfer process within the soil and is a key parameter in various engineering applications, including shallow geothermal energy exploitation, thermal energy storage, underground power cable systems, nuclear waste isolation, among others. This parameter can be determined through various methods, including predictive models based on soil characteristics, laboratory tests on small soil samples, in-situ needle probe, field thermal response tests (TRT) on larger soil volumes, and the field thermal cone dissipation test (T-CPT), which utilize the well-known cone penetration test (CPT) device. In-situ tests offer the advantage of providing rapid results for soil thermal conductivity under actual field conditions. This study focuses on field measurements of the thermal conductivity of soils based on the thermal cone dissipation test, using a low-cost and portable equipment compared to the conventional CPT apparatus. For this purpose, the cone tip of a Dynamic Probing Light (DPL) was modified to estimate soil thermal conductivity and named T-DPL (Thermal Dynamic Probing Light). The T-DPL equipment is easy to operate, lightweight, and manually controlled. The validation of the test procedure was demonstrated through model tank tests in both dry and saturated sand. Following laboratory validation, T-DPL tests were conducted at an unsaturated soil site in Brazil. The moisture content and groundwater table at the test site vary seasonally, influencing the previously measured ground thermal conductivity results from TRT experiments. The use of the T-DPL provided consistent results and effectively detected the impact of seasonal moisture content variations on soil thermal conductivity.

土壤导热系数控制着土壤内部的传热过程，是各种工程应用的关键参数，包括浅层地热能开采、热能储存、地下电力电缆系统、核废料隔离等。该参数可以通过多种方法确定，包括基于土壤特征的预测模型、小土壤样品的实验室测试、原位针探针、大土壤体积的现场热响应测试（TRT）以及利用著名的锥贯入测试（CPT）装置的现场热锥耗散测试（T-CPT）。原位测试的优点是可以在实际现场条件下快速得出土壤导热系数的结果。本研究的重点是基于热锥耗散试验的土壤热导率的现场测量，与传统的CPT设备相比，使用了低成本和便携式的设备。为此，对动态探测光（Dynamic Probing Light， DPL）的锥尖进行了改进，以估计土壤的热导率，并命名为T-DPL （thermal Dynamic Probing Light，热动态探测光）。T-DPL设备易于操作，重量轻，可手动控制。通过在干砂和饱和砂中进行模型罐试验，验证了试验方法的有效性。在实验室验证之后，T-DPL测试在巴西的一个非饱和土场地进行。试验场的含水率和地下水位随季节变化，影响了TRT试验之前测量的地面导热系数结果。T-DPL的使用提供了一致的结果，并有效地检测了季节含水量变化对土壤导热系数的影响。

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引用次数: 0

Hydrochemical characteristics and genetic mechanisms of multi-type thermal springs of Nyingchi City, Southeastern Qinghai-Tibet Plateau

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-16 DOI: 10.1016/j.geothermics.2025.103575

Dawa Nan , Sihang Han , Pingcuo Gesang , Qifeng Zeng , Yadong Zheng , Zhao Liu , Sang Gong , Duoji Gesang , Linjie Zhang

Thermal springs are widely used as direct, sustainable and pollution-free shallow geothermal resources. Understanding their genesis and evolution will ensure their sustainable development and use. Nyingchi City, located in the southeast of the Qinghai-Tibet Plateau, is rich in geothermal resources. This study investigated the formation and evolution of thermal springs in Nyingchi City by studying the hydrogeochemical characteristics of 44 thermal and cold spring groups. Hydrochemical analyses of the springs show that the water types of geothermal water in the area include the HCO₃, HCO₃Cl, HCO₃-SO₄ and SO₄ types. These water types are due to the weathering of silicate minerals, the dissolution of carbonate and sulfate minerals, and the cation exchange between water and rock, with the HCO₃-Cl type geothermal water containing a mixture of deep-seated materials. Using the silica-enthalpy mixing model, the cold-water mixing proportion in the geothermal fluid was determined to be 60–94%, while the silica geothermometer yielded an initial reservoir temperature range of 105.7–257.4 °C for the deep thermal aquifer. The hydrogeochemical characteristics of the thermal springs in Nyingchi City show discernible spatial differences. Thermal spring water-rock interaction occurs at a significant depth in the west, followed by interaction at a shallower depth in the east, and shallow interaction along the Eastern Himalayan Syntaxis(EHS), where high-temperature steam flash heats the shallow cold water. These new findings advance the understanding of the formation process of multi-type thermal springs in Nyingchi City and provide scientific guidance for the sustainable development and use of regional thermal spring geothermal resources.

温泉作为一种直接、可持续、无污染的浅层地热资源，得到了广泛的应用。了解它们的起源和演变将确保它们的可持续发展和利用。本文通过对林芝市44个冷热泉群水文地球化学特征的研究，探讨了林芝市温泉的形成与演化。泉水水化学分析表明，该地区地热水的水类型包括HCO3、HCO3Cl、HCO3-SO4和SO4类型。这些水类型是由于硅酸盐矿物的风化作用，碳酸盐和硫酸盐矿物的溶解作用，以及水和岩石之间的阳离子交换作用，与HCO₃-Cl型地热水含有深层物质的混合物。利用二氧化硅-焓混合模型，确定了地热流体中冷水混合比例为60 ~ 94%，而二氧化硅地温计测得深层热含水层的初始储层温度范围为105.7 ~ 257.4℃。林芝温泉水文地球化学特征具有明显的空间差异性。温泉-岩石相互作用发生在西部的显著深度，其次是东部较浅深度的相互作用，以及沿东喜马拉雅结带（EHS）的浅层相互作用，高温蒸汽闪热浅层冷水。这些新发现促进了对林芝多类型温泉形成过程的认识，为区域温泉地热资源的可持续开发利用提供了科学指导。

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引用次数: 0

Cenozoic tectonic-thermal evolution of the Xihu Sag, East China Sea Basin: Implications for hydrocarbon generation in continental margin basins 东海盆地西湖凹陷新生代构造-热演化：对大陆边缘盆地生烃的启示

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-15 DOI: 10.1016/j.geothermics.2025.103530

Qiwen Yao , Hui Diao , Jian Chang , Wu Zhang , Ruiheng Zhan , Hangyuan Gao , Kefu Li

This study investigates the Cenozoic tectono-thermal evolution of the Xihu Sag in the East China Sea Basin, a rift–inversion sub-basin at the convergent boundary of the Eurasian, Pacific, and Philippine Sea plates. The findings have broad implications for hydrocarbon generation and thermal history reconstruction in similar continental margin basins globally. By integrating present-day geothermal data, low-temperature thermochronology, vitrinite reflectance, and fluid inclusion analysis, this study reconstructs the thermal history and source rock maturation processes in the Xihu Sag. The geothermal gradient ranges from 16 to 46 °C/km at depths of 0–4 km, with an average of 31.8 °C/km, and surface heat flow varies between 34 and 88 mW/m², averaging 52.3 mW/m². These thermal regimes show a southeast-high to northwest-low trend, primarily influenced by lithospheric thinning, thermal refraction, and basement morphology. Thermal history modeling reveals a significant cooling event during the Late Miocene (14–7 Ma), corresponding to the Longjing tectonic phase, with progressive southeast-to-northwest deformation. Erosion magnitudes exceeded 800 m in marginal anticline zones, while the central Pinghu Slope Belt experienced denudation rates up to 246 m/Ma. Basin modeling indicates that basement heat flow decreased during the Early to Middle Miocene but increased again during tectonic inversion, significantly influencing source rock maturation. The Pinghu Formation source rocks reached peak hydrocarbon generation by the end of the Miocene. Fluid inclusion data indicate two primary hydrocarbon charging phases (∼15–9 Ma and ∼5–0 Ma), consistent with modeled expulsion stages. This study introduces a robust, multi-parameter integrated framework to rigorously assess the geothermal state, tectonic characteristics, and petroleum generation potential of continental margin basins. This methodological paradigm shift fundamentally advances the approaches to thermal history reconstruction and hydrocarbon exploration, providing a reliable and universally applicable solution for analogous geological settings.

本文研究了位于欧亚、太平洋和菲律宾海板块汇聚边界上的裂谷反转子盆地——东海盆地西湖凹陷的新生代构造-热演化。这些发现对全球类似大陆边缘盆地的生烃和热史重建具有广泛的指导意义。综合现今地热资料、低温年代学、镜质组反射率和流体包裹体分析，重建了西湖凹陷热史和烃源岩成熟过程。地温梯度在0 ~ 4 km范围内为16 ~ 46℃/km，平均为31.8℃/km，地表热流在34 ~ 88 mW/m²之间，平均为52.3 mW/m²。这些热区主要受岩石圈减薄、热折射和基底形态的影响，呈现东南高向西北低的趋势。热史模拟显示，晚中新世（14-7 Ma）发生了一次显著的降温事件，与龙井构造相对应，并伴有东南向西北的渐进式变形。边缘背斜带侵蚀强度超过800 m，平湖斜坡带中部剥蚀速率高达246 m/Ma。盆地模拟表明，早中新世至中中新世基底热流减少，构造反转期间基底热流再次增加，对烃源岩成熟有显著影响。平湖组烃源岩在中新世末达到生烃高峰。流体包裹体数据显示了两个主要的烃类充注阶段（~ 15-9 Ma和~ 5-0 Ma），与模拟的排烃阶段一致。该研究引入了一个稳健的多参数综合框架，以严格评估大陆边缘盆地的地热状态、构造特征和生油潜力。这种方法范式的转变从根本上推进了热史重建和油气勘探的方法，为类似的地质环境提供了可靠且普遍适用的解决方案。

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引用次数: 0

Professor Manfred Hochstein (1932–2025)

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-15 DOI: 10.1016/j.geothermics.2025.103562

Eva Hochstein , Sadiq J. Zarrouk , Alan Nunns

引用次数: 0

Fracture identification in hot dry rock using TSD-Unet: From feature extraction to quantitative analysis of geometric parameters 基于TSD-Unet的干热岩石裂缝识别：从特征提取到几何参数定量分析

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-15 DOI: 10.1016/j.geothermics.2025.103569

Mangu Hu , Tianyu Fu , Xiaobin Yang , Lei Peng , Chun Wang , Xiangfeng Lv

Accurate identification and quantitative characterization of fractures in hot dry rock (HDR) reservoirs are of great significance for the efficient development of geothermal resources. To address the challenges associated with precise fracture recognition and quantification, an improved fracture identification model named TSD-Unet is proposed in this study. This model is constructed by integrating the Spatial Group-wise Enhance (SGE) module and Dynamic Snake Convolution (DSC) module into the U-Net architecture. This integration enables the TSD-Unet model to extract both spatial and multi-morphological features of fractures from granite failure images. The SGE and DSC modules, inserted after the convolutional layers, allow the model to effectively combine spatial and morphological features of fractures. Ablation experiments and multi-model comparison experiments were conducted using a granite fracture image dataset. The comparison results demonstrate the competitiveness of the TSD-Unet model in segmentation performance, achieving an accuracy (Acc) of 62.88 % and an intersection over union (IoU) of 46.06 %. Compared to the traditional U-Net model, TSD-Unet shows improvements of 8.02 % in Acc and 9.51 % in IoU. Based on the segmentation results and the proposed feature computation method, quantitative analyses were performed on fracture characteristics such as length, area, average width, and maximum width, revealing that the results based on TSD-Unet closely match actual conditions. This research provides a precise and efficient method for intelligent fracture identification and feature extraction in HDR reservoirs, offering significant theoretical guidance for improving the efficiency of geothermal resource exploitation.

热干岩储层裂缝的准确识别和定量表征对地热资源的高效开发具有重要意义。为了解决与精确裂缝识别和量化相关的挑战，本研究提出了一种改进的裂缝识别模型，称为TSD-Unet。该模型通过将空间群智增强（SGE）模块和动态蛇卷积（DSC）模块集成到U-Net体系结构中来构建。这种集成使TSD-Unet模型能够从花岗岩破坏图像中提取裂缝的空间和多形态特征。在卷积层之后插入SGE和DSC模块，使模型能够有效地结合裂缝的空间和形态特征。利用花岗岩断裂图像数据集进行消融实验和多模型对比实验。对比结果表明，TSD-Unet模型在分割性能上具有一定的竞争力，准确率（Acc）达到62.88%，交集/联合（IoU）达到46.06%。与传统的U-Net模型相比，TSD-Unet在Acc和IoU方面分别提高了8.02%和9.51%。基于分割结果和提出的特征计算方法，对裂缝长度、面积、平均宽度、最大宽度等特征进行了定量分析，结果表明基于TSD-Unet的分割结果与实际情况吻合较好。本研究为HDR储层裂缝智能识别和特征提取提供了一种精确、高效的方法，对提高地热资源开发效率具有重要的理论指导意义。

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引用次数: 0

Comparison of thermo-mechanical response between the grouted method and ordinary micro steel pipe energy pile under multiple heating and cooling cycles 灌浆法与普通微钢管能源桩在多次加热和冷却循环下的热-力学响应比较

IF 3.9 2区工程技术 Q3 ENERGY & FUELS

Geothermics

Pub Date : 2025-12-13 DOI: 10.1016/j.geothermics.2025.103571

Hong Chang , Xing Wu , Zhengheng Gan , Yuan Du , Huicheng Jiang , Zhaoxuan Wang , Ming Ma

As an energy underground structure combining load-bearing and heat exchange capabilities, micro energy pile (MEP) offers unique advantages for geothermal heating compared with conventional energy pile (EP). Despite their potential, micro energy piles (MEP) have received far less attention compared to conventional energy piles (EP). This study presents a comparative analysis of the thermo-mechanical response characteristics of micro grouted steel pipe energy pile (MGSPEP) and micro steel pipe energy pile (MSPEP). The results indicate the influence range of the soil temperature field for both types of piles extends to approximately four times the pile diameter. The heat exchange rate of the MGSPEP ranges from 44.5 to 49.4 W/m, showing no significant difference compared with that of EP. The maximum additional tensile stress and compressive stress of the two piles account for less than 5 % of the tensile and compressive design values of the steel pipe. MGSPEP has a smaller pile and soil relative displacement. The settlement of MGSPEP and MSPEP accounts for 0.4 % D and 1.1 % D of the pile diameter, respectively. The accumulative soil pressure at the pile tip of MSPEP is 1.08 kPa, and MGSPEP accounts for only 28.7 % of MSPEP. The findings of this study provide new insights and references for the structural and energy retrofitting applications of MGSPEP in both existing and newly constructed buildings. This is expected to enhance the sustainability of geothermal energy systems.

微能源桩作为一种集承载和换热于一体的地下能源结构，与传统能源桩相比，具有独特的地热采暖优势。尽管具有潜力，但与传统能源桩相比，微能源桩受到的关注远远不够。对微灌浆钢管能源桩（MGSPEP）和微钢管能源桩（MSPEP）的热-力学响应特性进行了对比分析。结果表明，土温场对两种桩的影响范围均扩大到桩径的4倍左右。MGSPEP的热交换率在44.5 ~ 49.4 W/m之间，与EP的热交换率无显著差异。两桩最大附加拉压应力占钢管拉压设计值的比例小于5%。MGSPEP具有较小的桩土相对位移。MGSPEP和MSPEP的沉降分别占桩径的0.4% D和1.1% D。MSPEP桩端累积土压力为1.08 kPa，仅占MSPEP的28.7%。本研究结果为MGSPEP在既有建筑和新建建筑中的结构和能源改造应用提供了新的见解和参考。预计这将提高地热能源系统的可持续性。

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