Spontaneous imbibition plays a crucial role in various engineering and industrial applications, with its efficiency significantly influenced by a range of factors. To unravel the intricate mechanisms behind these factors, our study employs pore-scale numerical simulations. Utilizing a color gradient model within the framework of the lattice Boltzmann method, we delve into how pore structure, wettability, and flow velocity within fractures collectively impact spontaneous imbibition. Our findings reveal that the dynamics of drainage and imbibition interfaces during countercurrent spontaneous imbibition are key determinants of imbibition efficiency. Specifically, the synergy between wettability and pore structure markedly affects the penetration depth and distribution characteristics of the imbibition interface, which, in turn, influences the imbibition's speed and duration. Moreover, the interaction between the flow velocity inside fractures and the configuration of adjacent pore structures significantly shapes the evolution of the drainage interface. This interplay is crucial as it can either enhance or hinder countercurrent spontaneous imbibition. These insights deepen our understanding of the pore-scale processes governing countercurrent spontaneous imbibition, laying a solid theoretical foundation for optimizing its application in engineering and industrial settings.

中文翻译：

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逆流自发渗吸动力学：润湿性、裂缝流和孔隙结构的综合影响

自发吸入在各种工程和工业应用中发挥着至关重要的作用，其效率受到一系列因素的显着影响。为了揭示这些因素背后的复杂机制，我们的研究采用了孔隙尺度数值模拟。利用格子玻尔兹曼方法框架内的颜色梯度模型，我们深入研究了裂缝内的孔隙结构、润湿性和流速如何共同影响自发渗吸。我们的研究结果表明，逆流自发渗吸过程中排水和渗吸界面的动态是渗吸效率的关键决定因素。具体而言，润湿性与孔隙结构之间的协同作用显着影响渗吸界面的渗透深度和分布特征，进而影响渗吸速度和持续时间。此外，裂缝内的流速与相邻孔隙结构的配置之间的相互作用显着影响排水界面的演变。这种相互作用至关重要，因为它可以增强或阻碍逆流自发吸入。这些见解加深了我们对控制逆流自发渗吸的孔隙尺度过程的理解，为优化其在工程和工业环境中的应用奠定了坚实的理论基础。