COLLABORATIVE RESEARCH: Closure of Thermodynamically Constrained Models for Multiphase Systems

合作研究：多相系统热力学约束模型的闭合

• 批准号: 9901432
• 负责人: William Gray
• 金额: $ 11.67万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9901432&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Closure; Thermodynamically; Constrained

9901432GrayTraditional models of multiphase flow in porous media are based in empiricism and correlation of experimental data. Over the past two decades significant effort has been expended in developing a theoretical basis for multiphase flow models grounded in conservation principles. These approaches both reveal assumptions implicit in the current models and paths to more rigorous and robust models. One of the most elegant and conceptually satisfying approaches is the thermodynamically constrained averaging theory approach (TCATA). Recent work with the TCATA has led to the formulation of a set of models for two-phase flow in porous media. Additional steps, however, are required to develop the TCATA fully. The goals of the current proposal are to move beyond pure theory and idealized porous media to the description of real systems to demonstrate the viability, importance, and necessity of the TCATA for describing the physics of multiphase flow in porous media.To meet the goals of this project, we will use a combination of theoretical, pore scale morphology and modeling, continuum scale modeling, and laboratory experimental approaches. This work will be accomplished by building upon and continuing an existing collaboration between Professor Cass T. Miller's group at the University of North Carolina and Professor William G. Gray's group at the University of Notre Dame. This proposal describes the joint work of both groups, with each institution submitting directly to NSF requesting the resources needed to accomplish their share of the work.This work will have additional applicability to any array of multiphase porous media systems in both natural and engineered systems. We expect several significant accomplishments from this work: (1) the development of a theoretical framework that includes film flow and disjoining pressures; (2) the formulation of capillary pressure as a function of both saturation and interfacial area, thereby reducing or eliminating the hysteresis found when capillary pressure is represented as a function of saturation only; (3) the development of constitutive relations that include dynamic geometric parameters in expressing the functional dependence of relative permeability; (4) formulation and implementation of a numerical algorithm to solve the extended set of model equations; and (5) comparison of experimental data with model results to reveal the strengths and weaknesses of our approaches and the needs for further advancement of methods that account for the physics of multiphase flow.

9901432灰色多相渗流的传统模型是建立在实验数据的经验性和相关性基础上的。在过去的二十年中，大量的工作已经花费在发展基于守恒原理的多相流模型的理论基础上。 这些方法既揭示了当前模型中隐含的假设，也揭示了通往更严格和更强大模型的道路。 最优雅和概念上令人满意的方法之一是几何约束平均理论方法（TCATA）。 最近的工作与TCATA导致制定了一套模型的两相流在多孔介质中。 然而，还需要采取更多的步骤来充分发展TCATA。 目前的建议的目标是超越纯理论和理想化的多孔介质的描述真实的系统，以证明的可行性，重要性和必要性的TCATA描述的物理多相流在多孔media.To满足本项目的目标，我们将使用理论，孔隙尺度形态和建模，连续尺度建模，实验室实验方法相结合。 这项工作将通过建立和继续卡斯T教授之间的现有合作来完成。北卡罗来纳州大学的米勒小组和威廉G.格雷在圣母大学的研究小组。 该提案描述了两个小组的联合工作，每个机构直接向NSF提交申请，要求提供完成其工作份额所需的资源。这项工作将对自然和工程系统中的任何多相多孔介质系统阵列具有额外的适用性。 我们期望从这项工作中获得几个重要的成果：（1）发展一个包括膜流和分离压力的理论框架：（2）将毛细管压力作为饱和度和界面面积的函数，从而减少或消除当毛细管压力仅表示为饱和度的函数时发现的滞后;（3）发展了包括动态几何参数的本构关系，以表达相对渗透率的函数依赖性;（4）制定和实施了求解扩展模型方程组的数值算法;以及（5）将实验数据与模型结果进行比较，以揭示我们的方法的优点和缺点以及进一步改进解释多相流物理的方法的需要。