CAREER:Advanced interface methods in heterogeneous porous materials: a multi-disciplinary and multi-scale framework

职业：异质多孔材料中的先进界面方法：多学科和多尺度框架

• 批准号: 1255622
• 负责人: Masa Prodanovic
• 金额: $ 44.91万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1255622&HistoricalAwards=false
• 关键词: CAREER; Advanced; interface; methods; heterogeneous

Many natural and artificial processes involve the simultaneous flow of two or three fluid phases (such as water, oil, and air) through porous media. However, the prediction of how fast the phases move and whether they can be retrieved is not trivial. It requires knowledge of the topology of different fluids in a complex three-dimensional space that ranges from simple soil to root-soil systems, and from a uniform sandstone to fractured carbonate rocks. Both porous media (soil or rock) and fluid properties (i.e. which fluid is preferentially wetting the rock surface) determine the final spatial distribution when multiple fluids are competing within pores. Furthermore, minuscule rock or soil pores often control which fluids become trapped and where. Quantifying the spatial arrangement of fluids in pores of complex geometry and varying wettability remains an unsolved fundamental problem. The project objective is to explore and quantify dynamic spatial fluid arrangements from first principles and their control on flow complexity of porous media. To address the objective, the project will develop a flexible, multiscale numerical method to describe two- and three-fluid phase flow configurations in porous materials of heterogeneous wettability. Through cooperation, detailed 3D experimental data imaged with x-ray microtomography of two and three-phase flow configurations will be available for both input and verification of the numerical method. Results will enable the quantification and upscaling of rock surfaces of different wettability, porous media roughness and the ultimate arrangement of fluids to larger spatial regions of interest.One example region of application is the Edwards Aquifer in Texas, which provides water for approximately two million people in the Austin and San Antonio metropolitan areas. The aquifer is formed by heterogeneous limestone, inter-bedded and overlain with sand/gravel sediments. Additional flow-path heterogeneity originates from faults and fractures: 95% of the flow occurs in a highly conductive fracture network, whereas 95% of water storage is in the rock matrix. The difference between fracture network conductivity and matrix storage, combined with highly erratic rainfall, are at the core of water management issues in central Texas. When it rains and water moves through fractures and out of the system exceedingly fast (thereby causing flash flooding); after a dry period, due to wettability changes and water/air competition in this heterogeneous reservoir, the storage matrix might be 90% full, but wells often become dry. Controlling a contaminant spill in such a heterogeneous medium (also known as karst) introduces the competition of three fluid phases in the pore space. Regardless of this specific example, the findings of the proposed research will become relevant to many different fields of research such as carbon dioxide sequestration in depleted oil reservoirs and in remediation and enhanced oil recovery efforts. Results will be of significant use in the extrapolation of existing theory and models to mixed wet, two- and three-fluid phase systems. In addition, a digital image repository for porous materials initiated along with this proposal will enhance research infrastructure and benchmarking of porous media theory, models and experiments. Finally, karst formations and water management issues are part of the everyday experience in Texas and they are ideal to educate a broad audience on geology, flow physics and chemistry, engineering as well as applied mathematics and computer science. Results from this project will be tested by teachers at professional development projects funded by the NSF and DOE, and then integrated into accessible online modules and included in an interactive exhibit in the Austin's Children Museum.

许多自然和人工过程涉及两个或三个流体相（如水，油和空气）通过多孔介质的同时流动。然而，预测相位移动的速度以及它们是否可以被检索并不是微不足道的。它需要了解复杂三维空间中不同流体的拓扑结构，从简单的土壤到根土系统，从均匀的砂岩到破碎的碳酸盐岩。多孔介质（土壤或岩石）和流体性质（即，哪种流体优先润湿岩石表面）决定了孔隙内多种流体竞争时的最终空间分布。此外，微小的岩石或土壤孔隙往往控制着哪些流体被困在哪里。量化复杂几何形状和不同润湿性的孔隙中流体的空间排列仍然是一个未解决的基本问题。该项目的目标是探索和量化动态空间流体安排的第一性原理和他们的控制多孔介质的流动复杂性。为了实现这一目标，该项目将开发一种灵活的多尺度数值方法，以描述非均匀润湿性多孔材料中的两相和三相流体流结构。通过合作，详细的三维实验数据成像与X射线显微断层摄影的两相流和三相流配置将可用于输入和验证的数值方法。结果将使不同的润湿性，多孔介质的粗糙度和流体的最终安排的岩石表面的量化和放大到更大的空间regions.One应用的一个示例区域是在得克萨斯州的爱德华兹含水层，它提供了约200万人在奥斯汀和圣安东尼奥大都市地区的水。含水层由非均质石灰岩形成，与砂/砾石沉积物互层并覆盖。另外的流动路径不均匀性来自断层和裂缝：95%的流动发生在高传导性的裂缝网络中，而95%的水储存在岩石基质中。裂缝网络传导性和基质储存之间的差异，加上高度不稳定的降雨，是德克萨斯州中部水管理问题的核心。当下雨时，水通过裂缝快速流出系统（从而导致山洪暴发）;经过一段干燥期后，由于这种非均质储层中的润湿性变化和水/空气竞争，储存基质可能充满90%，但威尔斯经常变干。在这种非均匀介质（也称为岩溶）中控制污染物溢出会在孔隙空间中引入三种流体相的竞争。无论这一具体例子如何，拟议研究的结果将与许多不同的研究领域有关，如枯竭油藏中的二氧化碳封存以及补救和提高石油采收率的努力。结果将是显着使用现有的理论和模型外推到混合湿，两个和三个流体相系统。此外，沿着这一提议启动的多孔材料数字图像库将加强多孔介质理论、模型和实验的研究基础设施和基准。最后，喀斯特地层和水管理问题是德克萨斯州日常经验的一部分，它们是教育广大观众了解地质学，流动物理学和化学，工程学以及应用数学和计算机科学的理想选择。该项目的结果将由NSF和DOE资助的专业发展项目的教师进行测试，然后整合到可访问的在线模块中，并包括在奥斯汀儿童博物馆的互动展览中。