Geomechanics for Energy and the Environment最新文献_第2页

Thermoporoelastic model for fluid-driven debonding of cement during CO2 injection in a vertical well 直井注二氧化碳过程中固井流体驱动脱粘热孔弹性模型

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2026-01-02 DOI: 10.1016/j.gete.2025.100785

A.V. Valov , E.V. Dontsov , F. Zhang

Well integrity is a critical challenge in carbon capture and storage (CCS) projects, where debonding of cement sheath can form preferential pathways for CO

_{2}

leakage. This study introduces a numerical framework for simulating fluid-driven debonding along the cement interfaces during CO

_{2}

injection. A pseudo-3D fracture propagation model, adapted to cylindrical well geometry, is coupled with a thermoporoelastic finite element mechanical model of the composite casing-cement-formation system. The framework accounts for poroelastic material behavior, thermal stresses, variations in fluid pressure and temperature, in-situ stress anisotropy, formation layering, and initial stress states induced by well construction and cement hydration. Fracture propagation is simulated in both vertical and circumferential directions, incorporating the effects of buoyancy, fluid viscosity, interfacial adhesion strength, and pressure-dependent leak-off. Numerical results reveal three distinct debonding regimes: crescent-shaped partial debonding, large incomplete debonding with non-monotonic aperture, and complete debonding that is characterized by a fully open channel around the circumference of the well. Sensitivity analysis reveals that debonding evolution is strongly influenced by cement shrinkage, injection conditions, cold fluid effects, and changes in reservoir stress over time. The model provides a predictive tool for assessing leakage risk and fracture evolution under varying cementing conditions, injection scenarios, and reservoir stress states.

在碳捕集与封存（CCS）项目中，井的完整性是一个关键的挑战，在CCS项目中，水泥环的脱粘会形成二氧化碳泄漏的优先途径。该研究引入了模拟二氧化碳注入过程中沿水泥界面流体驱动脱粘的数值框架。将拟三维裂缝扩展模型与套管-水泥-地层复合系统的热孔弹性有限元力学模型相结合，该模型适用于柱形井的几何形状。该框架考虑了孔隙弹性材料特性、热应力、流体压力和温度变化、地应力各向异性、地层分层以及井建和水泥水化引起的初始应力状态。在垂直和周向两个方向上模拟裂缝扩展，同时考虑浮力、流体粘度、界面粘附强度和压力相关泄漏的影响。数值结果显示了三种不同的脱粘模式：月牙形部分脱粘，非单调孔径的大不完全脱粘，以及以井周周围完全开放的通道为特征的完全脱粘。敏感性分析表明，水泥收缩、注入条件、冷流体效应和油藏应力随时间变化对脱粘演化有强烈影响。该模型为评估不同固井条件、注入方案和油藏应力状态下的泄漏风险和裂缝演化提供了预测工具。

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引用次数: 0

Impact of pore-water salinity and sulphate concentration on the breakdown pressure of limestone rocks 孔隙水矿化度和硫酸盐浓度对石灰岩破裂压力的影响

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-25 DOI: 10.1016/j.gete.2025.100781

Mohammad Rezaee, Mohsen Masihi, Hassan Mahani

Hydraulic fracturing (HF) is widely used to enhance production from subsurface energy systems, with fracturing pressure governed by geochemical and geomechanical factors. While similar rock types and stress conditions may exist across regions, rock-pore water interactions can vary, influencing fracture behavior. A key factor overlooked in current models is sulphate ion variability in pore water, which interacts with carbonate rock and alters its mechanical properties. This study investigates how sulphate concentration in the formation water affects HF in limestone rock, using laboratory-scale experiments and theoretical modeling. A custom-built 2D fracturing apparatus was used to evaluate breakdown pressure (BP) dependency on sulphate concentration and injection rate. Additional insights were obtained through surface complexation modeling, disjoining pressure calculations, microscopic imaging, and elemental analysis. Results indicate that BP increases with injection rate, facilitating smoother, more effective fractures. The primary weakening mechanism arises from alterations in intergranular forces due to brine composition changes, rather than mineral dissolution or precipitation. Salinity affects BP by modifying both rock tensile strength and local stress state. Notably, BP exhibits a non-monotonic trend with sulphate concentration, reaching maximum weakening at 1 M salinity. High salinity results in lower BP, leading to irregular, less conductive fractures, while lower sulphate levels enhance injectivity post-HF, improving reservoir performance. These novel findings provide critical insights for optimizing HF and injection operations, particularly when brine salinity differs from formation water, enabling more effective well stimulation strategies in carbonate reservoirs.

水力压裂（HF）被广泛用于提高地下能源系统的产量，压裂压力受地球化学和地质力学因素的影响。虽然不同地区可能存在相似的岩石类型和应力条件，但岩石-孔隙-水的相互作用可能会有所不同，从而影响裂缝行为。当前模型忽略的一个关键因素是孔隙水中硫酸盐离子的变化，它与碳酸盐岩相互作用并改变其力学性质。本研究利用实验室规模的实验和理论模型研究了地层水中硫酸盐浓度对石灰岩中HF的影响。使用定制的2D压裂仪来评估破裂压力（BP）与硫酸盐浓度和注入速率的关系。通过表面络合模拟、分离压力计算、显微成像和元素分析获得了更多的见解。结果表明，BP随着注入速度的增加而增加，有利于裂缝更平滑、更有效。主要的弱化机制是由于卤水成分变化引起的晶间力的改变，而不是矿物溶解或沉淀。盐度通过改变岩石抗拉强度和局部应力状态来影响BP。值得注意的是，BP随硫酸盐浓度呈非单调趋势，在1 M盐度时减弱最大。高矿化度导致BP降低，导致裂缝不规则、导流性差，而较低的硫酸盐水平提高了hf后的注入能力，改善了储层性能。这些新发现为优化HF和注入作业提供了重要的见解，特别是当盐水盐度与地层水不同时，可以实现更有效的碳酸盐岩储层增产策略。

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引用次数: 0

Discussion of “Assessment of an amended soil as a climate adaptive barrier: Element testing and physical modelling” “作为气候适应屏障的改良土壤的评估：元素测试和物理模型”的讨论

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-25 DOI: 10.1016/j.gete.2025.100784

Vishnu Gopakumar, Bharat Venkata Tadikonda

This discussion examines methodological and interpretative aspects of “Assessment of an amended soil as a climate adaptive barrier: element testing and physical modelling” by Rana et al., emphasizing critical insights for enhancing barrier reliability. Key concerns include the potential for measurement errors arising from delayed hydraulic response and equilibration protocols associated with tensiometer and ceramic sensor techniques. These issues cause significant disparities in soil water characteristic curve (SWCC) and hydraulic conductivity results. The discussion highlights that breakthrough mechanisms in fine-textured, water treatment residual (WTR) amended soils are best characterized by suction equilibrium rather than hydraulic conductivity convergence, aligning with recent research on capillary barrier systems. Environmental and long-term durability factors are discussed, including the implications of organic matter degradation, vegetation compatibility, and atmospheric drying cycle effects. The verification of sensor response times and long-term assessment are recommended to improve the robustness and utility of WTR-based climate adaptive barriers.

本讨论探讨了Rana等人的“作为气候适应性屏障的改良土壤评估：元素测试和物理建模”的方法和解释方面，强调了提高屏障可靠性的关键见解。关键问题包括延迟液压响应和与张力计和陶瓷传感器技术相关的平衡协议所引起的测量误差的可能性。这些问题导致土壤水分特征曲线（SWCC）和导水系数结果存在显著差异。讨论强调，细结构水处理残留物（WTR）修正土壤的突破机制最好是通过吸力平衡而不是水力导电性收敛来表征的，这与最近对毛细屏障系统的研究一致。讨论了环境和长期耐久性因素，包括有机质降解、植被兼容性和大气干燥循环效应的影响。建议对传感器响应时间进行验证和长期评估，以提高基于wtr的气候适应屏障的鲁棒性和实用性。

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引用次数: 0

Thermally driven fracturing in hot dry rock systems and the role of wellbore cooling 热干岩系统中的热驱动压裂及井筒冷却作用

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-22 DOI: 10.1016/j.gete.2025.100783

Abolfazl Ghadimi, Mozhdeh Sajjadi, Mohammad Emami Niri

Hydraulic fracturing in hot dry rock (HDR) geothermal reservoirs is strongly influenced by thermal stresses arising from the temperature difference between the injected fluid and the surrounding rock. This study develops a three-dimensional extended finite element (XFEM) model to analyze the dominant early-stage mechanism of wellbore wall cooling and its effect on fracture initiation and propagation. The model captures the coupled thermo-mechanical behavior of the rock and evaluates how thermal contraction at the wellbore alters breakdown and propagation pressures. Sensitivity analyses show that increasing the temperature difference between the injected fluid and the rock significantly reduces the required fracturing pressure, while the magnitude of this effect depends on the in-situ stress field, thermal expansion coefficient, and Young’s modulus. In contrast, variations in thermal conductivity and permeability have negligible impact on the pressure response. The results confirm that wellbore cooling governs the thermal stress contribution during the early stages of fracturing, while fluid-flow-induced thermal gradients become more relevant at later stages. Overall, the findings improve understanding of thermo-mechanical interactions in HDR fracturing and can assist engineers in predicting fracturing pressures and optimizing stimulation strategies in geothermal energy development.

热干岩（HDR）地热储层水力压裂受注入流体与围岩温差产生的热应力的强烈影响。建立了三维扩展有限元（XFEM）模型，分析了井筒壁冷却的主要早期机理及其对裂缝萌生和扩展的影响。该模型捕获了岩石的耦合热-力学行为，并评估了井筒中的热收缩如何改变破裂和扩展压力。敏感性分析表明，增加注入流体与岩石之间的温差可以显著降低所需的压裂压力，而这种影响的大小取决于地应力场、热膨胀系数和杨氏模量。相比之下，导热系数和渗透率的变化对压力响应的影响可以忽略不计。结果证实，在压裂初期，井筒冷却对热应力的贡献起主导作用，而在压裂后期，流体诱导的热梯度对热应力的影响更大。总的来说，这些发现提高了对HDR压裂热-力学相互作用的理解，可以帮助工程师预测压裂压力，优化地热能源开发中的增产策略。

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引用次数: 0

Micromechanical modeling of long-term creep behavior of quasi-brittle rocks considering thermo-mechanical coupling effects 考虑热-力耦合效应的准脆性岩石长期蠕变行为细观力学模拟

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-20 DOI: 10.1016/j.gete.2025.100782

Boran Huang , Jin Zhang , Qi-Zhi Zhu , Lunyang Zhao , Sili Liu

A temperature-dependent micromechanical creep–damage constitutive model is proposed within the framework of irreversible thermodynamics and homogenization theory to investigate the long-term thermo-mechanical behavior of quasi-brittle rocks. The model explicitly couples frictional sliding and microcrack propagation as the dominant modes of energy dissipation, where the friction coefficient, critical damage resistance, and damage threshold are expressed as temperature-dependent functions. Subcritical crack growth is incorporated to capture time-dependent damage accumulation and strain development. Model validation is conducted against triaxial thermo-creep experiments on gneissic granite, deep coals, and Beishan granite. The simulations reproduce the complete creep evolution – primary, secondary (steady-state), and tertiary (accelerated) stages – with relatively few parameters. The results clarify the role of creep rate—controlling factors, reveal the mechanisms of damage evolution and strain-rate acceleration under elevated temperatures, and demonstrate the promoting effect of thermal loading on energy dissipation. This unified framework not only advances the understanding of rock creep under coupled thermal–mechanical fields but also provides a theoretical basis for assessing the long-term thermal stability and reliability of deep underground engineering structures.

在不可逆热力学和均质化理论的框架下，提出了一种温度相关的微力学蠕变损伤本构模型，研究了准脆性岩石的长期热-力学行为。该模型明确耦合摩擦滑动和微裂纹扩展作为能量耗散的主要模式，其中摩擦系数、临界损伤抗力和损伤阈值表示为温度相关函数。亚临界裂纹扩展被纳入捕捉随时间的损伤积累和应变发展。通过对麻质花岗岩、深部煤和北山花岗岩的三轴热蠕变试验对模型进行了验证。该模拟以相对较少的参数再现了完整的蠕变演化过程——初级、二级（稳态）和三级（加速）阶段。研究结果明确了蠕变速率控制因素的作用，揭示了高温下损伤演化和应变速率加速的机理，并论证了热载荷对能量耗散的促进作用。这一统一框架不仅促进了对热-力耦合作用下岩石蠕变的认识，而且为深部地下工程结构的长期热稳定性和可靠性评价提供了理论依据。

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引用次数: 0

Enhanced soil-pile friction using colloidal silica grouting in granular soils 颗粒土中硅胶灌浆增强桩土摩擦

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-13 DOI: 10.1016/j.gete.2025.100780

Alvaro Boiero , Enrique Romero , Marcos Arroyo , Giovanni Spagnoli

Grouting the soil–pile interface can significantly enhance shaft friction in driven and vibrated piles. This observation is well documented for conventional cementitious grouts, but not for alternative low-carbon grouts. In this study the potential of a novel low-viscosity binder—colloidal silica (CS)—to improve steel–granular soil interfaces is explored. Direct shear tests under constant normal stiffness were performed to simulate sand–pile interface behavior on quartz sand specimens permeated with CS. A range of initial relative densities, initial effective normal stresses and constant normal spring stiffness values was selected to mimic conditions likely to be encountered by long piles on offshore sedimentary environments. The study examines the influence of CS dosage and of steel interface roughness. Pre- and post-grout interface shear tests were conducted to evaluate the influence of injection. The results demonstrate that colloidal silica significantly increases interface friction. Practical implications for pile design are discussed.

对桩土界面进行注浆，可显著提高桩身摩阻力。这一观察结果在常规胶凝注浆中得到了很好的证明，但在替代低碳注浆中却没有得到证实。本研究探讨了一种新型低粘度粘结剂——胶体二氧化硅（CS）改善钢-颗粒-土壤界面的潜力。采用恒法向刚度直剪试验模拟了CS渗透石英砂试件的砂-桩界面特性。选择一系列初始相对密度、初始有效正应力和恒定的正向弹簧刚度值来模拟近海沉积环境中长桩可能遇到的情况。研究了CS用量和钢界面粗糙度的影响。通过注浆前和注浆后界面剪切试验，评价注浆对注浆效果的影响。结果表明，胶体二氧化硅显著增加了界面摩擦力。讨论了桩设计的实际意义。

引用次数: 0

A multi-method integration approach for determining draw angles in underground metal mining: A case study of the kuogeshaye gold mine 地下金属开采角度确定的多方法集成方法——以郭格沙耶金矿为例

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-11 DOI: 10.1016/j.gete.2025.100777

Jiahui Tian , Ruiyang Bi , Jian Zhou , Zupu Xuan , Kun Du

Accurate determination of the draw angle is critical for defining surface subsidence boundaries and ensuring the safety of surface infrastructure during mining operations. To overcome the limitations of single-method approaches, this study proposes a multi-method integration framework. Using the Kuogeshaye Gold Mine as a case study, the framework effectively combines theoretical calculation, particle swarm optimization–support vector machine prediction, and numerical simulation. The maximum relative error between the results achieved using the three methods was only 5.1 %. Additionally, an analytic hierarchy process-based weighted fusion strategy was used to integrate the results from the three methods, yielding a more reliable determination. The final draw angles were 73.5° and 74.7° for a hanging wall and footwall, respectively. Engineering applications demonstrated that this method significantly enhanced the accuracy of surface subsidence zone-boundary delineation, offering a transferable methodology for determining the rock draw angle and ensuring safe mining in deep mines.

准确确定地表倾角对于确定地表沉陷边界、保障地表基础设施安全是至关重要的。为了克服单一方法方法的局限性，本研究提出了一个多方法集成框架。以Kuogeshaye金矿为例，该框架有效地将理论计算、粒子群优化-支持向量机预测和数值模拟相结合。三种方法测定结果的最大相对误差仅为5.1% %。此外，采用基于层次分析法的加权融合策略对三种方法的结果进行综合，得到更可靠的结果。上盘和下盘的最终抽采角度分别为73.5°和74.7°。工程应用表明，该方法显著提高了地表沉陷带边界圈定的精度，为确定深部矿山岩层倾角、保障矿山安全开采提供了一种可转移的方法。

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引用次数: 0

Mathematical foundations for play-agnostic thermo-poro-hydro-mechanical modeling of hydraulic fracture initiations from perforated wells: Towards a predictive tool 射孔井水力裂缝起裂的热-孔隙-水力力学模型的数学基础：一种预测工具

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-11 DOI: 10.1016/j.gete.2025.100778

Nassim Bouabdallah, Andreas Michael

The initiation of hydraulically-induced (fluid-driven) fractures for stimulation purposes in hydrocarbon-rich reservoirs can be predictively modeled employing a physics-based approach via a novel pseudo-three-dimensional (pseudo-3D) approximation. The rationale for such an approach lies in the orientation of hydraulic fracture (HF) initiation being determined by mapping stress distributions around the intersection between the wellbore and a perforation tunnel (i.e., the perforation base); the presumed location of HF initiations. The derived closed-form expressions couple thermal, poroelastic, and hydromechanical effects (TPHM) and are controlled by the reservoir’s rock properties and the fluid pressures at the perforation base. Most importantly, this physics-based approach is play-agnostic. The developed TPHM model enables identifying favorable conditions for HFs initiating perpendicularly to the wellbore (“transverse-HF initiations,” as opposed to “longitudinal-HF initiations” axially to the wellbore). This is the desired orientation of HF initiation in virtually every reservoir-stimulation-treatment target zone in today’s prolific low-permeability shale plays; longitudinal-HF initiations can induce several completion and production-related issues triggered by near-wellbore HF tortuosity. The utility of the play-agnostic TPHM model is easily reversible, as it can help estimate the fracture initiation pressure (FIP) at a given orientation of HF initiation. These FIP values provide the basis for formation-breakdown-pressure (FBP) predictions. By solving the derived closed-form expression, our dual-utility, play-agnostic TPHM model provides means for engineers to understand how to manipulate human-controlled parameters from the surface (such as pressurization rates and perforation phasing) to optimize stimulation treatments across various target rock formations, ultimately maximizing the well productivity. Through the promotion of transverse-HF initiation at the lowest possible FBP, near-wellbore fluid tortuosity is suppressed, minimizing early screenouts and enhancing stimulated-well performance that leads to overall more efficient stimulation treatments.

在富含油气的储层中，以增产为目的的水力诱导（流体驱动）裂缝的形成可以采用一种基于物理的方法，通过一种新的伪三维（pseudo-3D）近似方法进行预测建模。这种方法的基本原理是，通过绘制井筒和射孔隧道（即射孔底部）相交处的应力分布来确定水力裂缝（HF）起裂的方向；HF起爆的假定位置。导出的封闭表达式耦合了热、孔弹性和流体力学效应（TPHM），并受储层岩石性质和射孔底部流体压力的控制。最重要的是，这种基于物理的方法是游戏不可知论的。开发的TPHM模型能够识别hf垂直于井筒的有利条件（“横向hf起始”，而不是“纵向hf起始”）。在当今多产的低渗透页岩区，这是几乎所有储层增产处理目标区中HF起爆的理想方向；由于近井HF弯曲，纵向HF起爆会引发一些完井和生产相关的问题。与储层无关的TPHM模型的实用性是很容易逆转的，因为它可以帮助估计在HF起裂的给定方向上的裂缝起裂压力（FIP）。这些FIP值为地层破裂压力（FBP）预测提供了基础。通过求解推导出的封闭表达式，我们的双重实用、不可知储层的TPHM模型为工程师提供了一种方法，让他们了解如何从地面操纵人为控制的参数（如加压速率和射孔相位），以优化不同目标岩层的增产措施，最终实现油井产能最大化。通过在尽可能低的FBP下促进横向hf启动，可以抑制近井流体弯曲度，最大限度地减少早期筛出，提高增产井的性能，从而实现更有效的增产处理。

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引用次数: 0

Effect of mixing time on deep cement mixing in very soft peaty clay 搅拌时间对极软泥炭土中深层水泥搅拌的影响

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 DOI: 10.1016/j.gete.2025.100775

Ashvitha Yoganathan , Nadeej H. Priyankara , Susanga Costa , Jaspreet Singh Pooni , Dilan Robert

Peaty clay is one of the weakest and most challenging soils to stabilize. Traditionally, pile foundations are used to transfer structural loads to deeper, more stable strata, particularly in areas with peat soils, where surface layers may be too weak or compressible to support heavy loads. However, this approach is often uneconomical for large-area infrastructure such as roads or moderately loaded structures. As a cost-effective alternative, the Deep Mixing Method (DMM) has been widely adopted. DMM involves the in-situ mixing of soil with binders to enhance the engineering properties of soft ground. Despite its extensive application in soft clays and loose sandy soils, the use of DMM in stabilizing soft peaty clays remains relatively underexplored. While various studies have explored binder types and mix proportions, critical factors such as mixing duration and technique, both essential for achieving effective soil stabilization, are not well understood in the context of peaty clays. This research evaluates the effects of mixing time and method, using cement as a binder, on the strength, failure behaviour, and microstructural characteristics of stabilized peaty clay after 7 and 28 days of curing. The findings demonstrate that a 20-minute wet mixing process yields the highest compressive strength, attributed to the formation of densely packed cement hydration products. Specimens mixed under optimal conditions exhibited a split failure mode, similar to concrete, while less or over-mixed samples displayed shear failure. The outcomes from the study are significant for optimizing the DMM as an efficient way of stabilizing these problematic soils.

泥炭土是最脆弱和最具挑战性的土壤之一。传统上，桩基被用来将结构荷载转移到更深、更稳定的地层，特别是在有泥炭土的地区，那里的表层可能太弱或可压缩，无法支撑重物。然而，对于大面积的基础设施，如道路或中等负荷的结构，这种方法往往不经济。作为一种经济有效的替代方法，深度混合法（DMM）已被广泛采用。DMM是将土与粘结剂原位混合，以提高软土地基的工程性能。尽管DMM在软粘土和松散砂质土中得到了广泛的应用，但其在软泥炭土稳定中的应用仍相对较少。虽然各种各样的研究已经探索了粘结剂类型和混合比例，但在泥炭粘土的背景下，诸如混合时间和技术等对实现有效土壤稳定至关重要的关键因素还没有得到很好的理解。本研究评估了搅拌时间和方法的影响，使用水泥作为粘合剂，对强度，破坏行为和稳定的泥炭粘土在养护7天和28天后的微观结构特征。研究结果表明，20分钟的湿搅拌过程产生了最高的抗压强度，这是由于形成了密实的水泥水化产物。在最佳搅拌条件下，试件表现出与混凝土相似的劈裂破坏模式，而拌合过少或过少的试件则表现出剪切破坏模式。研究结果对优化DMM作为稳定这些问题土壤的有效方法具有重要意义。

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引用次数: 0

Quantifying thermo-hydraulic coupling in fractured geothermal reservoirs through discrete fracture network modeling based on field characterization 基于现场表征的离散裂缝网络建模量化裂缝性地热储层热-水力耦合

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-12-01 DOI: 10.1016/j.gete.2025.100773

Yanyan Li , Yuanshuo Ma , Ximin Bai , Binghong Fan

Fracture networks govern geothermal resource potential by controlling fluid flow and heat transfer dynamics. However, dynamic coupling mechanisms between fracture networks and thermo-hydraulic processes remain poorly quantified, hindering predictive capacity for long-term geothermal performance. To overcome this limitation, this study develops a geologically representative discrete fracture network (DFN) model by applying Monte Carlo simulation to field-measured fracture data from a granite outcrop in southwestern China. A coupled thermo-hydraulic model is established using the DFN model, validated against Lauwerier's analytical solution and numerically simulated. By quantifying thermal breakthrough, our results reveal that the system's sensitivity to fracture aperture decreases with increasing aperture, and that fracture aperture exerts a far stronger influence on thermal breakthrough than injection pressure. Besides, higher rock thermal conductivity enhances sustainable heat production by delaying thermal depletion through improved heat replenishment from the reservoir matrix. Quantified pressure impacts show 22 MPa delivers 50 % higher initial heat extraction than 18 MPa, but the marginal gain in cumulative heat production per unit pressure difference decreases, revealing the short-term advantages and long-term limitations of high-pressure operations.

裂缝网络通过控制流体流动和传热动力学来控制地热资源潜力。然而，裂缝网络与热水力过程之间的动态耦合机制仍然难以量化，这阻碍了对长期地热性能的预测能力。为了克服这一局限性，本研究采用蒙特卡罗模拟方法，建立了具有地质代表性的离散裂缝网络（DFN）模型，并对中国西南花岗岩露头的现场测量裂缝数据进行了分析。采用DFN模型建立了热-液耦合模型，并对Lauwerier解析解进行了验证和数值模拟。通过对热突破进行量化，研究结果表明，系统对裂缝孔径的敏感性随着裂缝孔径的增大而降低，裂缝孔径对热突破的影响远大于注入压力。此外，较高的岩石导热系数通过提高储层基质的热量补充来延缓热耗竭，从而增强了可持续的产热能力。量化压力影响表明，与18 MPa相比，22 MPa的初始热抽提量高出50% %，但单位压差累积产热边际增益减小，揭示了高压作业的短期优势和长期局限性。

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引用次数: 0