Interfacial Controls on Dynamics and Equilibration in Porous Media

多孔介质动力学和平衡的界面控制

• 批准号: 1344877
• 负责人: Dorthe Wildenschild
• 金额: $ 38.77万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1344877&HistoricalAwards=false
• 关键词: Interfacial; Controls; Dynamics; Equilibration; Porous

Interfacial Controls on Dynamics and Equilibration in Porous MediaMost current macroscopic theories of multi-phase flow are based on the combined equations of Darcy's Law and an empirical relationship between capillary pressure and saturation. In recent years, a number of studies have shown that this state of affairs is not necessarily optimal. However, in a given porous medium, saturation and interfacial areas are independent variables, i.e., many different configurations resulting in a range of interfacial areas are possible for a single saturation. Awareness of this effect of interfacial forces on multi-phase flow has led to the development of alternative theories based on fundamental thermodynamic considerations in which interfacial areas are introduced as separate thermodynamic entities. Thus capillary pressure becomes a function of both saturation and specific fluid-fluid interfacial area and it has been suggested that the system will be uniquely described by this functional dependence. Recent work has indicated that a single unique surface cannot indisputably describe two-phase flow under nonequilibrium conditions, suggesting that there may be something else missing from the theory. The goal of the proposed work is to improve on a paucity of delicate measurements and generate highly unique data sets from which strategic advances can be made on a number of fronts with respect to the fundamental dynamics of multi-phase flow in porous media. The data generated will consist of dynamic drainage and imbibition experiments during which x-ray tomographic images will be captured such that the fluid phases can be tracked in unprecedented detail in three dimensions. This will allow for measurement of developing interfacial areas, curvatures, and trapping behavior of the fluid phases. This novel data set can be used in a combined effort to validate findings based on multi-phase theories and for a broader exploration of interfacial dynamics, in particular the formation of interfacial area and curvature evolution. Improved understanding of the physics of multi-phase flow in porous media has societal impacts through applications in various fields such as groundwater management and remediation, soil and agricultural science, petroleum engineering, and geologic sequestration of CO2. This project aims to generate new data set that will not only first and foremost support progress in understanding the role of interfaces, and their dynamic behavior, on porous media flow and transport, but also improve on existing theories describing these processes. The generated high-resolution imagery will be made available to the broader scientific community through digital archiving. Ultimately, this will allow for improved management of natural resources and ability to reliably engineer porous systems leading to improvements in water usage and energy development.

多孔介质中动力学和平衡的界面控制目前大多数多相流的宏观理论是基于达西定律和毛管压力与饱和度之间的经验关系的组合方程。近年来，一些研究表明，这种状况不一定是最佳的。然而，在给定的多孔介质中，饱和度和界面面积是独立变量，即，对于单一饱和，导致一定范围的界面面积的许多不同构造是可能的。认识到这种影响的界面力对多相流的发展，导致替代理论的基础上，基本的热力学考虑，其中界面面积作为单独的热力学实体。因此，毛细管压力成为饱和度和特定的流体-流体界面面积的函数，并且已经建议系统将由该函数依赖性唯一地描述。最近的工作表明，一个单一的独特的表面不能无可争议地描述两相流在非平衡条件下，这表明可能有其他东西从理论中丢失。拟议的工作的目标是改善缺乏精细的测量，并产生高度独特的数据集，从战略上的进步，可以在一些方面的多孔介质中的多相流的基本动力学。生成的数据将包括动态排水和吸胀实验，在此期间，将捕获X射线断层图像，以便可以在三维空间中以前所未有的细节跟踪流体相。这将允许测量发展中的界面面积、曲率和流体相的捕获行为。这一新的数据集可以用于一个综合的努力，以验证多相理论的基础上的研究结果，并为更广泛的探索界面动力学，特别是形成的界面面积和曲率的演变。对多孔介质中多相流物理学的进一步理解通过在地下水管理和修复、土壤和农业科学、石油工程和CO2地质封存等各个领域的应用产生了社会影响。该项目旨在生成新的数据集，不仅首先支持理解界面的作用及其动态行为对多孔介质流动和运输的进展，而且还改进了描述这些过程的现有理论。生成的高分辨率图像将通过数字存档提供给更广泛的科学界。最终，这将改善自然资源的管理，并能够可靠地设计多孔系统，从而改善用水和能源开发。