【摘要】 岩体裂隙中反应性流体渗流诱发的溶蚀过程对岩土工程安全具有重要影响，而由溶液密度差异所诱发的重力效应下，倾斜裂隙介质的溶蚀机制尚不明确。通过孔隙尺度数值模拟与可视化试验相结合的方法，系统探究了不同倾角裂隙溶蚀模式及渗透率演化规律。结果表明：倾斜裂隙溶蚀过程中，溶液密度差异诱发的浮力对流会形成“漩涡”流动结构，其中沿裂隙长度方向的浮力对流主导溶蚀通道发育，而垂直方向影响可忽略。通过引入理查森数建立了溶蚀模式判据：当理查森数Ri_Ⅱ>10时属浮力对流主导模式，倾角增大促进虫洞发育并降低突破注液量；当理查森数Ri_Ⅱ≤10时属强制对流主导模式，其溶蚀形态由注入流速控制，呈现紧凑溶蚀、虫洞溶蚀和均匀溶蚀3种模式。在此基础上，建立了考虑重力效应的最佳注入流速的理论模型，实现不同倾角下裂隙介质最佳注入流速的准确预测。研究成果为可溶岩区地下工程渗流控制提供了理论依据，对CO₂地质封存、地浸采矿等工程的安全评估具有重要指导意义。更多还原

【Abstract】 The dissolution process induced by reactive fluid flow in rock fractures significantly impacts geotechnical engineering safety, while the dissolution mechanisms of inclined fractures under gravitational effects induced by solution density differences remain unclear. This study systematically investigates the dissolution patterns and permeability evolution of fractures with different inclinations through pore-scale numerical simulations and visualization experiments. Results indicate that buoyancy-driven convection caused by solution density differences generates “vortex-like” flow structures during inclined fracture dissolution, where buoyancy convection along the fracture length dominates channel development, whereas gravitational effects in the vertical direction can be negligible. A criterion for the transition of dissolution patterns was established using the Richardson number（Ri_Ⅱ）: When Ri_Ⅱ > 10（buoyancy-dominated regime）, increased inclination promotes wormhole growth and reduces the required injection volume for breakthrough; when Ri_Ⅱ≤ 10（forced convection-dominated regime）, dissolution patterns are governed by injection velocity, manifesting as compact dissolution, wormhole dissolution, or uniform dissolution. A theoretical model for optimal injection velocity incorporating gravitational effects was developed, enabling accurate predictions across varying inclinations. This research provides a theoretical guidance for seepage control in underground engineering within soluble rock formations and offers critical insights for safety assessments in CO₂ geological storage, in-situ leaching mining, and related applications.更多还原