EAPSI: Studying Hysteresis of Three-Phase Flow in Porous Media Using Dynamic X-ray Microtomography

本研究将研究在岩石基质中流动的三个流体相的实时去向和传输。这些流体流动实验的可视化将通过快速x射线微层析成像完成，当流体被注入或从系统中排出时，它可以产生岩石中流体位置的3D图像。理解多孔介质中多种流体之间的相互作用非常重要，因为它控制着影响人类和环境健康的许多环境过程(例如，提高石油采收率、地质封存二氧化碳、修复含水层中的石油泄漏)。该项目将在澳大利亚堪培拉的澳大利亚国立大学与禤浩焯·谢泼德博士合作进行，谢泼德博士是快速X射线微层析成像技术的先驱，也是3D图像处理尖端数学技术的领先科学家。很少有实验室具备快速X射线显微层析成像技术，因此，合作者可用的仪器和专业知识为完成这项研究提供了独特的机会。这项研究将利用图像可视化和处理方面的进展来收集独特的数据集，并计算与模拟多孔介质中的三相流体流动系统(例如，受污染的含水层中的水、空气和石油的并发传输)相关的状态变量。该项目将使用澳大利亚国立大学最先进的基于实验室的X射线系统和先进的数学重建算法，这些算法利用先验信息实时收集微断层扫描。毛细压力、流体-流体界面面积和欧拉特性的状态变量将从三维图像中计算出来，这些图像以前对于动态流动条件下的三相流动系统是无法获得的。这些状态变量在两相流中很重要，它们将相互关联，以更好地了解三相流的物理特性，还将与以前在准平衡条件下获得的数据集进行比较，以了解流动条件对流体拓扑和界面面积生成的影响。该奖项由东亚和太平洋夏季研究所计划设立，支持一名美国研究生的夏季研究，由NSF和澳大利亚科学院联合资助。

This research will study the real-time fate and transport of three fluid phases flowing together through a rock matrix. The visualization of these fluid-flow experiments will be accomplished with fast x-ray microtomography which can produce 3D images of the position of fluids within a rock while fluids are being injected or drained from the system. The interaction between multiple fluids in porous media is important to understand because it controls many environmental processes (e.g. enhanced oil recovery, geologic CO2 sequestration, oil spill remediation in an aquifer) which affect human and environmental health. This project will be conducted at the Australian National University in Canberra, Australia in collaboration with Dr. Adrian Sheppard, a pioneer in the fast x-ray microtomography technique and a leading scientist in cutting-edge mathematical techniques for 3D image processing. Few laboratories are equipped for fast x-ray microtomography; therefore, the available instrumentation and expertise of the collaborators provide a unique opportunity to accomplish this research.This research will utilize advances in image visualization and processing to collect unique data sets and calculate state variables relevant in modeling three-phase fluid flow systems in porous media (e.g. concurrent water, air, and oil transport in a contaminated aquifer). The project will use the Australian National University's state-of-the-art lab-based x-ray system and advanced mathematical reconstruction algorithms that utilize a priori information to collect microtomography scans in real-time. State variables of capillary pressure, fluid-fluid interfacial area, and Euler characteristic will be calculated from 3D images which have been previously unobtainable for three-phase flow systems under dynamic flow conditions. These state variables are important in two-phase flow and will be correlated to better understand the physics of three-phase flow and will also be compared with previous data sets obtained under quasi-equilibrium conditions to understand the effect of flow conditions on fluid topology and interfacial area generation.This award, under the East Asia and Pacific Summer Institutes program, supports summer research by a U.S. graduate student and is jointly funded by NSF and the Australian Academy of Science.