Models and Adaptive Methods for Compressible Multi-Material Reactive Flow

可压缩多材料反应流的模型和自适应方法

• 批准号: 1016188
• 负责人: Donald Schwendeman
• 金额: $ 29.63万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-15 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1016188&HistoricalAwards=false
• 关键词: Models; Adaptive; Methods; Compressible; Multi

Applications in a variety of scientific fields require accurate computation of physical phenomena that are driven by mechanisms operating at very fine scales. Such problems often involve mixtures involving several distinct phases and/or constituents. A successful approach requires two ingredients: multi-phase and/or multi-physics mathematical models that are valid at the larger scale of observation but contain within them all the necessary information from the finer scales, and a computational strategy that is robust and generates accurate numerical solutions. One such problem is the initiation and propagation of detonation waves in high-energy solid explosives, a problem that is of major interest to those engaged in the stewardship of the nation's nuclear arsenal and is the main focus of the proposed research.The proposed work is a contribution to the modeling and computation of high-speed, multi-material flow. The project is focused on detonations in confined, high-energy granular explosives, and the aim is to accurately predict the response of the explosive/confiner system to an igniting stimulus. The problem encompasses many scales; the molecular at which energy-liberating reactions occur, the meso at which physical processes determine the sites of ignition and the modes of combustion, and the macro at which the explosive does work to push or deform. It is proposed that the entire assembly be modeled as a hybrid multi-phase multi-fluid mixture. Problems at both the meso and the macro scales will be examined computationally; the former to uncover and quantify processes leading to discrete sites of ignition and the latter to explain possible mechanisms of detonation failure. The mathematical models will be nonlinear systems of hyperbolic partial differential equations with source terms, and a central goal of the research will be the development of numerical methods that provide an accurate description of material interfaces over long times.

在各种科学领域的应用需要精确计算由在非常精细的尺度上运行的机制驱动的物理现象。这类问题通常涉及几种不同相和/或成分的混合物。一个成功的方法需要两个要素：多相和/或多物理场数学模型，这些模型在更大的观测尺度上有效，但其中包含了来自更细尺度的所有必要信息，以及一个鲁棒的计算策略，并产生准确的数值解。其中一个问题是高能固体炸药中爆震波的起爆和传播，这是那些从事国家核武库管理工作的人感兴趣的主要问题，也是拟议研究的主要焦点。所提出的工作对高速、多物质流的建模和计算做出了贡献。该项目侧重于密闭高能颗粒炸药的爆轰，目的是准确预测炸药/密闭系统对点火刺激的响应。这个问题涉及许多层面；释放能量反应发生的分子，物理过程决定点火位置和燃烧方式的介观，以及炸药产生推力或变形的宏观。建议将整个总成建模为混合多相多流体混合物。在中观和宏观尺度的问题将进行计算检查；前者揭示和量化导致点火离散点的过程，后者解释引爆失败的可能机制。数学模型将是具有源项的双曲偏微分方程的非线性系统，研究的中心目标将是发展数值方法，以提供长时间内材料界面的准确描述。