Dynamic Redistribution of Fluids in Porous Media

多孔介质中流体的动态重新分布

• 批准号: 1314663
• 负责人: Laura Pyrak-Nolte
• 金额: $ 35.9万
• 依托单位: Purdue University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-15 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1314663&HistoricalAwards=false
• 关键词: Dynamic; Redistribution; Fluids; Porous; Media

Most subsurface activities perturb the natural state of fluids in soil and rock because fluids are often injected, withdrawn or transported through the subsurface. All of these techniques induce changes in the local pressure field that initially perturb a multiphase system into a nonequilibrium condition that, over time, relaxes to steady-state or quasi-static distributions. The relaxation depends on pore-scale processes such as dynamic contact angles, air-water interface geometry, temporal changes in wettability, and local heterogeneities in the porous media. This research focuses on an experimental investigation of the dynamic redistribution of fluids in porous media by connecting internal microscopic perturbations to external macroscopic behavior. The study will assess the contributions of wettability, pore topology and films to the redistribution of immiscible fluids in a porous medium in the transition from dynamic to steadystate/quasi-static conditions. A combination of experimental techniques will be used that include the fabrication of transparent micro-models with built-in electro-kinetic actuators tomanipulate fluids at the pore scale internal to the pore network; the fabrication of 3D transparent micro-models using a new grain deposition method; and the measurement of 2D & 3D fluid distributions using fluorescent imaging and laser confocal microscopy to determine the role of absorbed films, corner fluids and pinned films on static and dynamic relations as a function of dimensionality. Analysis of experimental datasets will determine which competing theories for static and dynamic constitutive relationships are supported by experimental evidence, and whether current theories are sufficient to describe multiphase fluid relaxation.Understanding the scaling of pore connectivity and the hydraulic properties of porous networks is of particular relevance today because of the intense activity in shale-gas which depends on networks of fractures to produce the gas, and because of attempts to sequester carbon dioxide in the subsurface. In addition, contaminant remediation efforts, chemical mixing, and biological tissue growth on synthetic porous media all depend on the complex interplay of geometry with the dynamics of fluids. This research will provide critical testing of theoretical methods used to predict flow and distributions of multiple fluids in porous media, and will enable scientists andengineers to connect interfacial areas, disconnected fluid phases and film geometry to macroscopic hydraulic properties.

大多数地下活动都会扰动土壤和岩石中流体的自然状态，因为通常会注入，撤回或通过地下运输。所有这些技术都会导致局部压力场的变化，最初将多相系统扰动到非平衡条件中，随着时间的流逝，它会放松到稳态或准静态分布。放松取决于孔隙尺度的过程，例如动态接触角，空气水接口几何形状，润湿性的时间变化以及多孔介质中的局部异质性。这项研究的重点是通过将内部显微镜扰动与外部宏观行为联系起来，对多孔培养基中流体的动态重新分布进行实验研究。该研究将评估从动态到稳态/准静态条件的过渡中，在多孔培养基中，润湿性，孔拓扑和膜对不混溶液的重新分布的贡献。将使用实验技术的组合，其中包括与内置的电动动力执行器的透明微型模型的制造，该模型在孔网络内部的孔隙尺度上对孔隙尺度上的液体进行了质化流体；使用新的晶粒沉积法制造3D透明微型模型；以及使用荧光成像和激光共聚焦显微镜测量2D和3D流体分布，以确定吸收膜，角流体和固定膜对静态和动态关系的作用，这是维度的函数。 Analysis of experimental datasets will determine which competing theories for static and dynamic constitutive relationships are supported by experimental evidence, and whether current theories are sufficient to describe multiphase fluid relaxation.Understanding the scaling of pore connectivity and the hydraulic properties of porous networks is of particular relevance today because of the intense activity in shale-gas which depends on networks of fractures to produce the gas, and because of attempts to sequester carbon地下中的二氧化物。此外，合成多孔培养基上的污染物修复工作，化学混合和生物组织生长都取决于几何与流体动力学的复杂相互作用。这项研究将对用于预测多孔培养基中多种流体的流量和分布的理论方法进行关键测试，并使科学家和工程师能够连接界面区域，断开的流体阶段以及膜几何形状与宏观水力特性。