Collaborative Research: Development of High-Resolution Finite-Volume Methods for Systems of Nonlinear Time-Dependent PDEs

合作研究：非线性时变偏微分方程组高分辨率有限体积方法的开发

• 批准号: 1115682
• 负责人: Alina Chertock
• 金额: $ 11.84万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1115682&HistoricalAwards=false
• 关键词: Collaborative; Research; Development; Resolution; Finite

The project is aimed at developing highly accurate, efficient and robust numerical methods for systems of nonlinear time-dependent PDEs, with particular reference to multidimensional hyperbolic systems of conservation/balance laws and related problems. The principal part of the proposed research will be focused on the development of new finite-volume methods that will provide an improved resolution of linear contact waves and incorporate new techniques for solving problems involving complicated nonlinear wave phenomena and blowing up/spiky solutions. The proposed methods will be applied to a variety of nonlinear problems, among which are systems of gas dynamics, nonlinear elasticity and acoustics systems, modern traffic flow models, several chemotaxis and bioconvection models, and others. These problems will be studied in the most challenging cases of high space dimensions, complex geometries and moving interfaces. For each problem, a high-resolution finite-volume scheme will be systematically derived in a way that the main properties satisfied by the underlying system of PDEs will be also satisfied on the discrete level. One of the key features of the new schemes will be their nonlinear stability, which will be ensured by ability of the scheme to preserve positivity of such physical quantities as density. To achieve this goal, several high-order positivity preserving techniques will be explored.Besides providing the examples that corroborate the analytical approach, the foregoing applications are of a substantial independent value for a broad class of problems arising in today's science including geophysics, meteorology, astrophysics, semiconductors, traffic flows, image processing, financial and biological modeling and many other areas. Development of modern high-resolution finite-volume methods as well as of supplementary techniques is essential for solving many practically important problems, some of which are currently out of reach because the existing numerical methods are either inefficient/inaccurate or not applicable at all.

该项目的目的是开发高精度、高效率和稳健的数值方法，用于非线性时变偏微分方程组，特别是关于守恒定律/平衡律的多维双曲型方程组和相关问题。拟议研究的主要部分将集中在开发新的有限体积方法，这些方法将提供更高的线性接触波的分辨率，并结合新的技术来解决涉及复杂非线性波现象的问题和爆炸/尖峰解。所提出的方法将应用于各种非线性问题，其中包括气体动力学系统、非线性弹性系统和声学系统、现代交通流模型、几种趋化性和生物对流模型等。这些问题将在最具挑战性的情况下进行研究，这些情况包括高空间维度、复杂的几何形状和移动的界面。对于每个问题，系统地推导出高分辨率的有限体积格式，使得基本偏微分方程组所满足的主要性质也将在离散水平上得到满足。新格式的关键特征之一是其非线性稳定性，这将通过该格式保持密度等物理量的正性来确保。为了实现这一目标，将探索几种高阶正性保持技术。除了提供证实分析方法的例子外，上述应用对于当今科学中出现的广泛类别的问题具有实质性的独立价值，包括地球物理、气象学、天体物理、半导体、交通流量、图像处理、金融和生物建模以及许多其他领域。现代高分辨率有限体积方法及其辅助技术的发展对于解决许多重要的实际问题是必不可少的，其中一些问题目前是无法解决的，因为现有的数值方法要么效率低下/不准确，要么根本不适用。