非平衡与多相复杂系统：离散Boltzmann方法与应用

项目名称： 非平衡与多相复杂系统：离散Boltzmann方法与应用

项目编号： No.11475028

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 许爱国

作者单位： 北京应用物理与计算数学研究所

项目金额： 82万元

中文摘要： 本项目发展离散玻尔兹曼(DB)等方法，研究非平衡与多相复杂系统。突破传统流体模型不易描述热力学非平衡行为和效应的局限性，发展适应一般状态方程系统、对流速、温度和可压性具有自适应性的DB模型。研究武器物理及众多工业领域关注度极高的流体界面不稳定性问题、非平衡相变及冲击波与多相流的相互作用、燃烧过程中的爆燃转爆轰及其反过程等。重点关注非平衡效应较强的局域结构及其影响：如表面张力和界面结构的演化特征与可能的致稳效应、相变过渡区相变过程和力学过程的竞争、化学活性区力学与化学反应进程之间的竞争。通过研究非平衡驱动力与响应之间的关系来理解传统流体描述的局限性，改进宏观物理建模，为非平衡行为的描述和度量提供一套有效的方法。关键技术包括复杂过程中特征结构的识别、特征尺度的提取和非平衡效应的描述。本项目的完成将有助于推进复杂系统多尺度物理建模与研究，为武器精密化设计和改进工业工艺提供技术支撑。

中文关键词： 非平衡态；多相流；复杂系统；格子玻尔兹曼方法；非线性科学

英文摘要： This project aims to develops methods like the Discrete Boltzmann (DB) , and study the nonequilibrium and multiphase flows.The developed DB models will make a breakthrough in modeling systems with general equation of state, systems with adaptive flow velocity,compressibility and temperature. We plan to study the hydrodynamic interfacial instabilities, nonequilibrium phase transitions, interactions between shock wave and multiphase flows, the transitions between deflagration and detonation in combustion phenomena, etc. The main focuses are the local structures with strong nonequilibrium effects and their influences. For example, (i) the interfacial tension, interface structures and their evolutions, as well as possible effects in stablizing the interfacial instabilities, (ii) the competetion between phase transition and mechanical procedures in the transition zones, (iii) the competetion between the mechanical process and the process of chemical reaction in the active zones. Via studying the responses to nonequilibrium driving forces we try to understand the limitations of traditional fluid mechanics, improve the macroscopic physical modeling, and finally present a set of consistent and effective methods to describe and measure the nonequilibrium behaviors. The key techniques include the identification of characteristic structures, extraction of the characteristic length scales and description of the nonequilibrium effects. The fulfilling of this project will advance the multiscale physical modeling and investigation of complex systems, will present technical supports for the refinement of weapon designs and progress of industrial technologies.

英文关键词： nonequilibrium state;multiphase flows;complex systems;lattice Boltzmann method;nonlinear science