驱替和溶解在日常生活和工业生产中十分常见，是油气开采、药物输运、碳 封存、海水淡化等领域中的瓶颈问题。在石油开采中，常采用酸化来增加油气产 量。酸化涉及两个关键步骤：注入酸液溶解岩石，改善储层渗透性；注入驱油剂 驱替石油，提高能源采收率。本文针对孔径分布影响下的驱替模式和流动溶解耦 合下的孔隙演化两个关键科学问题，采用实验和理论相结合的方式开展了研究。 在实验上，将光刻技术和微流控技术结合，制作了一批可溶解的多孔介质材料， 其中的孔径分布可以调控；同时结合高清CMOS 相机和图像处理技术，发展了 一种多孔介质溶解过程中测量流场和浓度场的非接触方法。在理论上，从孔隙尺 度弯液面行为以及作用力的相互竞争两个方面，推导了压力平衡方程，凝练出了 临界毛细数用以预测驱替模式的转变；同时，综合考虑了流动和溶解的耦合作用， 推导了孔隙率演化方程。本文的主要研究内容及研究成果如下： 孔径分布的无序程度影响了毛细力和黏性力相互竞争，导致了驱替过程中界 面失稳模式存在差异。根据分形维数和驱替饱和度，将实验结果划分为四种驱替 模式。通过孔隙尺度下弯液面的行为，阐明了不同驱替模式间的差异。综合考虑 了孔径分布无序程度、润湿性和注入速率对驱替中界面行为的影响，给出了临界 毛细数，并绘制了相关相图，可用来预测驱替模式间的转变。 孔径分布的无序程度影响了溶解和流动的相互竞争，导致了溶解动力学过程 存在差异。结合微流控技术和图像处理技术，在实验上系统的探究了孔径分布对 多孔介质溶解过程的影响。在不同孔径分布和注入速率下，观测到了四种溶解形 貌，阐明了孔径分布无序程度对溶解过程的影响。结合流场、浓度场观测方法， 揭示了多孔介质的溶解过程受到溶液流动和物质溶解的耦合作用。综合考虑了注 入速率和孔径分布，建立了可以预测和调控溶解过程中多孔介质演化的理论模型。 针对多孔介质内驱替和溶解过程，聚焦孔径分布和注入速率这两个变量，进 行了大量实验，阐明了孔径分布对驱替模式的影响，绘制了驱替模式转变相图， 揭示了流动溶解耦合下的孔隙演化规律，建立了多孔介质演化模型，用于预测和 调控驱替以及酸蚀过程，期望能够从理论上指导能源开采领域，提高石油的采收 率，助力国家能源重大需求。

In the realms of daily life and industrial production, displacement and dissolution are ubiquitously encountered, posing significant challenges in sectors such as oil and gas extraction, drug delivery, carbon sequestration, and desalination. In petroleum engineering, acidization is commonly employed to augment hydrocarbon yields. Acidization encompasses two pivotal stages: acid injection for rock dissolution, enhancing reservoir permeability; and oil displacement by a displacing agent, boosting energy recovery efficiency. Addressing the critical scientific issues of displacement patterns influenced by pore size distribution and coupled flow-dissolution-induced pore evolution, this study employed an integrated experimental and theoretical approach. Experimentally, a series of dissolvable porous media with controllable pore size distributions were fabricated through a combination of photolithography and microfluidic technology. A non-contact method for measuring the flow and concentration fields during the dissolution process of porous media was developed using high-definition CMOS camera and image processing techniques. Theoretically, from the perspective of the competition between capillary and viscous forces at the pore scale, the pressure equilibrium equation was derived, leading to a critical capillary number for predicting transition in displacement modes. Additionally, considering the interplay of flow and dissolution, the pore volume evolution equation was derived. The main research contents and findings are summarized below: The disorder degree of pore size distribution influences the competition between capillary and viscous forces, resulting in differences in instability patterns during displacement. Four displacement modes were classified based on fractal dimensions and displacement saturation. Through pore-scale behavior of menisci, the distinctions among different displacement modes were elucidated. By comprehensively considering the effects of pore size distribution randomness, wettability, and injection rate on interfacial dynamics in displacement, the critical capillary number was determined, and a phase diagram was plotted to predict transitions between displacement modes. The disorder degree of pore size distribution affects the competition between dissolution and flow, leading to variations in the dissolution kinetics. Experimentally, four morphologies of dissolution under different pore size distributions and injection rates were observed, revealing the impact of pore disorder on the dissolution process. Through the combined use of flow field and concentration field observation methods, it was revealed that the dissolution process in porous media is governed by the coupled effects of solution flow and material dissolution. Considering the injection rate and pore size distribution, a theoretical model was established to predict and control the evolution of porous media during the dissolution process. Focusing on displacement and dissolution processes within porous media, with pore size distribution and injection rate as variables, extensive experiments were conducted. The influence of pore size distribution on displacement mode was elucidated, and a phase diagram for displacement mode transitions was constructed. The rules governing pore evolution under the coupling of flow and dissolution were unveiled, and a porous media evolution model was established to forecast and regulate the displacement and acidizing processes. It is envisioned that these theoretical insights will guide the energy extraction industry, improving oil recovery rates, and supporting major national energy demands.