Existence, Uniqueness, and Regularity for Equations in Mathematical Fluid Mechanics

数学流体力学方程的存在性、唯一性和正则性

• 批准号: RGPIN-2019-05410
• 负责人: Yu, Xinwei
• 金额: $ 1.53万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=758372
• 关键词: Existence; Uniqueness; Regularity; Equations; Mathematical

This proposal is an effort to address the three major obstacles, nonlinearity, nonlocality, and coupling, in the mathematical study of partial differential equations arising from fluid mechanics. These equations not only govern fluid flows, but also model many phenomena in science and technology, even everyday life. The methods and techniques developed in the proposed research will shed new light on the study of such equations and may lead to resolution of major open problems. The proposal involves three main parts. 1.The method of pressure moderation. Together with students and co-authors, I have proposed a novel approach to the study of fluid mechanical equations. In this project I will further develop this new method and apply it to major open problems in mathematical fluid mechanics, in particular the regularity of solutions to the 3D Navier-Stokes equations. Goals: - Prove existence theorems for pressure moderators with desired properties; - Prove new regularity criteria for fluid mechanical equations through the application of the method of pressure moderation. 2.Wild solutions for coupled systems. I will develop a new convex integration framework that is both convenient and powerful in the study of coupled systems. Goals: - Construct pathological solutions with optimal regularity for coupled systems such as the MHD and Boussinesq equations. - Develop a new convex integration method for the study of coupled systems. 3.Regularity criteria with weak time integrability. In the past two years, I have proposed a new method to prove regularity criteria with weak time integrability for fluid mechanical equations. In this project, I will further develop this new method into a versatile and powerful framework for the study of regularity problems in mathematical fluid mechanics. Goals: - Prove improvements and generalizations of the weakly nonlinear Gronwall inequality which is a key ingredient in our new method. - Prove new regularity criteria for fluid mechanical equations. - Synthesize our method with the classical epsilon regularity theory into a systematic method for the proof of local regularity criteria with weak time integrability. These three parts will provide thorough training for three PhD students. The students will gain expertise in partial differential equations and related fields, and will be well-prepared for future careers in academia. I expect many interesting problems to "spin-off" from the proposed research to serve as motivating first projects for undergraduate summer research, the best opportunity to improve equity, diversity, and inclusion in mathematics.

这个建议是一个努力，以解决三个主要的障碍，非线性，非局部性和耦合，在数学研究的偏微分方程所产生的流体力学。这些方程不仅控制流体流动，还模拟了科学技术甚至日常生活中的许多现象。在拟议的研究中开发的方法和技术将为此类方程的研究提供新的思路，并可能导致解决主要的开放问题。 该建议包括三个主要部分。 1.压力调节方法。 与学生和合著者一起，我提出了一种新的方法来研究流体力学方程。在这个项目中，我将进一步发展这种新方法，并将其应用于数学流体力学中的主要开放问题，特别是三维Navier-Stokes方程解的正则性。 目标：- 证明具有所需性质的压力调节器的存在定理; -通过应用压力调节方法证明流体力学方程的新正则性准则。 2.耦合系统的广泛解决方案。 我将开发一个新的凸积分框架，这是既方便又强大的耦合系统的研究。 目标：-为耦合系统（如MHD和Boussinesq方程）构造具有最佳规律性的病态解。 - 发展一种新的凸积分方法用于耦合系统的研究。 3.弱时间可积的正则性准则。 在过去的两年中，我提出了一种新的方法来证明流体力学方程的弱时间可积性的正则性准则。在这个项目中，我将进一步发展这种新方法，使之成为研究数学流体力学中正则性问题的通用而强大的框架。 目标：-证明弱非线性Gronwall不等式的改进和推广，这是我们新方法的关键组成部分。 - 证明了流体力学方程的新正则性准则。 - 将我们的方法与经典的正则性理论相结合，形成一个系统的方法，用于证明弱时间可积的局部正则性准则。 这三个部分将为三名博士生提供全面的培训。学生将获得偏微分方程和相关领域的专业知识，并为未来的学术生涯做好准备。我希望从拟议的研究中“衍生”出许多有趣的问题，作为本科生暑期研究的第一个激励项目，这是提高数学公平性、多样性和包容性的最佳机会。