Utilization of Percolation Theory and Multiphysics' Concept to Develop Dynamic Modeling and Accurate Upscaling Approaches for Two-Phase Flow during Immiscible Displacement of Heavy Oil in Porous Media

重油采收率通常较低，并且大量未采收的重油留在储层中。稠油开采需要提高石油采收率（EOR）过程，其从根本上引起多孔介质中的连续两相或三相流动（不混溶或混溶驱替）。这种提高采收率技术的成功应用需要对多孔介质中的流动机理有更详细的了解。利用动态渗流网络模型研究了稠油饱和多孔介质中两相流动（非混相驱替）的基本机理，并将其应用于稠油油藏。由于在各种提高采收率技术中涉及到许多流动和传输机制，因此本研究的重点将是在稠油系统中的热水动态不混溶驱替和溶剂注入，以便实现所有提出的短期和长期目标。该研究计划将有助于填补多孔介质中多相流领域的知识空白。*虽然动态孔隙网络模型的研究已经有多年的历史，但其在稠油系统中的应用研究还很少。建立了一种考虑热水导热系数和注溶剂导热系数的稠油多物理动态渗流网络模型。借助该多物理动态渗流网络模拟，将研究孔隙尺度非均质性，特别是孔隙连通性和孔径分布、粘度比M、毛管数Ca、重力、热导率以及稠油和溶剂（CO2）性质对（热水和溶剂）驱替的影响。逾渗理论中的一个基本概念是渗透率k服从普适的标度律（k~（z-zc），其中z是多孔介质的配位数，zc是逾渗阈值，与孔径分布有关）。泛标度律与网络格点无关，对规则网络和无序网络（岩石孔隙空间为无序网络）都成立，并可推广到两相流。基于网络模拟，可以推导出稠油系统中孔隙尺度非均质性、M、Ca、热导率与某些宏观性质（相对渗透率、残余油饱和度、粘性指进）之间的“普适”性质和高阶关系（或数学模型）。放大的关系和数学模型将通过微观模型和填砂实验进行验证。*所有的结果，包括多物理动态渗流网络建模和放大模型，将使EOR过程中更复杂的相关现象的研究，如注入溶剂到含有盐水的孔隙空间。这些结果使研究人员和工业工程师能够优化石油生产的性能。

Heavy oil recovery is typically low, and a significant amount of unrecovered heavy oil is left in the reservoir. Heavy oil production requires enhanced oil recovery (EOR) processes, which fundamentally cause continuous two- or three- phase flow (immiscible or miscible displacement) in porous media. The successful applications of such EOR techniques require more detailed knowledge of flow mechanisms in porous media.***The objective of this study is to investigate the fundamental mechanisms of two phase flow (immiscible displacement) in porous media saturated with heavy oil using dynamic percolation network modeling, and its application in heavy oil reservoirs. Since there are many flow and transport mechanisms involved in various EOR techniques, the focus of this study will be on the dynamic immiscible displacement with hot-water, and solvent injection in heavy oil systems so that all proposed short and long term objectives can be achieved. This research program will help fill the knowledge gap in the area of multiphase flow in porous media.***Although dynamic pore-network modeling has been studied for years, its application in heavy oil systems has rarely been investigated. We will develop a multiphysical dynamic percolation network modeling method with integrated thermal conductivity of hot-water and solvent injection in heavy oil systems. With the help of this multiphysical dynamic percolation network modeling, the effects of pore scale heterogeneity, particularly pore connectivity and pore-size distribution, viscosity ratio M, capillary number Ca, gravity, thermal conductance and effects of properties of heavy oil and solvent (CO2) on the (hot-water and solvent) displacement will be studied.***A basic concept in percolation theory is that permeability k obeys the universal' scaling law (k~(z-zc), where z is coordination number of porous media, zc is percolation threshold and is related to pore size distribution). Universal' scaling law is independent of network lattice and is valid in both regular and disorder networks (pore space of rocks is disorder network), which can be extended to two-phase flow. 'Universal' properties and upscale relations (or mathematical models) between pore-scale heterogeneity, M, Ca, thermal conductance and some macroscopic properties (relative permeability, residual oil saturation, viscous fingering) in heavy oil systems can be derived based on network simulations. The upscaled relations and mathematical models will be validated with experiments on micromodel and sandpacks.***All results, including the multiphysical dynamic percolation network modeling and upscaling models, will enable study of more complex related phenomena in EOR processes, such as injection of solvent into pore space containing saline water. Such results allow researchers and industry engineers to optimize the performance of oil production.