Advancing Mechanistic Understanding of Two-Fluid-Phase Flow in Porous Medium Systems

促进多孔介质系统中两相流动的机理理解

• 批准号: 1619767
• 负责人: Cass Miller
• 金额: $ 46.08万
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1619767&HistoricalAwards=false
• 关键词: Advancing; Mechanistic; Understanding; Two; Fluid

Two-fluid-phase porous medium systems are systems that contain a solid phase and two distinct immiscible fluid phases that fill the pore space between solid particles. This general class of system arises in many applications of interest to society, including water infiltration from the Earth's surface, carbon sequestration, gas production from hydraulically fractured wells, petroleum recovery, land-atmosphere interaction, engineered treatment processes, and a wide range of biomedical applications (e.g. tumor growth, dermal transport, etc.). Our scientific understanding of porous medium systems is embodied in mechanistic mathematical models, which are used to evaluate such porous medium systems, make predictions, guide engineering design, and to inform policy decisions. Because the length of many porous medium systems is much greater than the natural length scale of the solid phase, the mathematical models intended to represent such systems are typically posed at a scale that neglects many aspects of the physical processes known to influence flow in such systems. While the physics are relatively well understood at the small scale, there has not existed a rigorous connection between the small, well-understood scale and the larger scale where problems must be solved. Recently, a theory has been developed that connects these two length scales and yields models that have the promise to be more physically realistic and accurate than the standard models used in practice. This research will reduce these new theoretical models to completely solvable forms, evaluate specific aspects of these models, and validate the models for a range of systems. Both small scale experiments and high-resolution modeling will be a used to accomplish these objectives. The results will be of widespread benefit to society because of the broad applicability of this class of problem, and the work will involve graduate students recruited from a pool that is rich in under-represented fractions of the population working in scientific research. Many critical problems in hydrology involve two-fluid-phase flow in porous medium systems. The proposed work will connect well-understood microscale processes with macroscale models using the thermodynamically constrained averaging theory (TCAT) that will yield closed, solved models that are evaluated and validated. Microfluidic experiments, and high resolution lattice Boltzmann simulations will be used to provide the fine scale detail needed to construct specific forms of closure relationships and support a thorough evaluation and validation of this new class of model. Computational and experimental methods and results will also be produced that will be of value independent of the theoretical manner in which macroscale systems are modeled. This work will have a significant set of broader impacts. The models developed are hydrologically motivated but have applicability far beyond hydrology. We will nurture and grow our set of collaborators that apply TCAT-based models for applications such as tumor growth, the effects of diabetes on extremal tissue, and engineered systems such as ultrafiltration membranes. The lattice-Boltzmann methods developed will be applicable to a wide range of systems beyond the hydrologic systems of focus in this work. A second edition of a book describing the theoretical advances will be produced to disseminate the findings of this work. Additional impacts include: (1) contributions to education through course content, student research, and science outreach; (2) participation of underrepresented researchers and linkages to minority recruitment programs; (3) broad dissemination of findings in hydrology, physics, engineering, and applied mathematics journals; and (4) digital archiving and dissemination of unique data sets and video images of experiments and high-resolution simulations.

双流体相多孔介质系统是包含固相和填充固体颗粒之间的孔隙空间的两个不同的不混溶流体相的系统。这类系统在许多社会感兴趣的应用中出现，包括从地球表面的水渗透、碳封存、从水力压裂威尔斯井的气体生产、石油回收、陆地-大气相互作用、工程处理过程以及广泛的生物医学应用（例如肿瘤生长、皮肤运输等）。我们对多孔介质系统的科学理解体现在机械数学模型中，这些模型用于评估此类多孔介质系统，进行预测，指导工程设计，并为政策决策提供信息。由于许多多孔介质系统的长度远大于固相的自然长度尺度，因此旨在表示此类系统的数学模型通常以忽略已知影响此类系统中的流动的物理过程的许多方面的尺度提出。虽然物理学在小尺度上被相对较好地理解，但在小的、被很好地理解的尺度和必须解决问题的更大尺度之间并不存在严格的联系。最近，一种理论已经发展起来，它将这两种长度尺度联系起来，并产生了比实践中使用的标准模型更具有物理现实性和准确性的模型。这项研究将减少这些新的理论模型，以完全可解的形式，评估这些模型的具体方面，并验证一系列系统的模型。小规模实验和高分辨率建模将用于实现这些目标。由于这类问题的广泛适用性，其结果将对社会产生广泛的益处，而且这项工作将涉及从一个从事科学研究的人口中大量代表性不足的部分中招募的研究生。水文学中的许多关键问题涉及多孔介质系统中的两相流。拟议的工作将连接良好理解的微观尺度的过程与宏观尺度的模型，使用几何约束平均理论（TCAT），将产生封闭的，解决的模型进行评估和验证。 微流体实验和高分辨率格子玻尔兹曼模拟将用于提供构建特定形式的闭合关系所需的精细尺度细节，并支持对这类新模型的全面评估和验证。计算和实验的方法和结果也将产生的价值，独立于宏观系统建模的理论方式。这项工作将产生一系列重要的广泛影响。开发的模型是出于水文动机，但适用性远远超出水文。我们将培养和发展我们的合作者，将基于TCAT的模型应用于肿瘤生长，糖尿病对极端组织的影响以及超滤膜等工程系统。格子玻尔兹曼方法的发展将适用于广泛的系统以外的水文系统的重点在这项工作中。为了传播这项工作的结果，将出版一本描述理论进展的书的第二版。其他影响包括：（1）通过课程内容、学生研究和科学推广对教育做出贡献;（2）代表性不足的研究人员的参与和与少数民族招募计划的联系;（3）在水文学、物理学、工程学和应用数学期刊上广泛传播研究结果;（4）数字存档和传播独特的实验和高分辨率模拟数据集和视频图像。