多组元系统的颗粒固体流体动力学（GSH）研究

Multi-component system of gases,liquids and granular materials is a important researching topics of granular physics, in which the reported works are however mostly experiments or numerical simulations, its basic governing equations are less addressed. To alter this, the project plan to start from the Granular Solid Hydrodynamics (GSH) of a single granular material, developed by the applicant and Mario Liu in Germany in these ten years, to further establish GSH equations for the multi-component systems, including their material models for thermodynamic potentials and transport coefficients. We will use the GSH to analyze explicitly some experiment data (reported in literatures and measured by this project), for showing and demonstrating that it accounts really the couplings and interactions among different components, as well as elasticity and friction of granular components etc., in an unified and correct way, could be then regarded as a basic theory of the systems. As the multi-component granular systems are widely met in industry and environment or geology, the project will be helpful for them from a physical point of view. Also it is of fundamental significance, as it is still doubted that the complicated nonlinearity and dissipation of the systems can be treated successfully with the classical physics on which the GSH is based.

气体、液体、一种或多种颗粒材料混合而成的多元系统是当前颗粒物质物理研究的重要方向之一，但大多是实验和数值模拟工作，对基本物理方程的研究严重不足。为改善之，本项目拟从申请人和德国的Prof. Liu Mario 近十来年原创的、现在已趋成熟的单组元颗粒固体流体动力学（GSH）出发，进一步建立多组元系统的GSH方程组，含热力学势和迁移系数等材料模型。并通过对一批实验数据（来自文献和本项目拟测量的）的分析应用，来表明和论证方程能正确反映各组元间的相互耦合与作用、和颗粒接触的弹性与摩擦效应，因此可作为统一描述多元颗粒系统所有宏观性质的理论基础。鉴于许多工业和环境地质材料是多元颗粒系统，项目将从物理基础的层面为这些领域提供理论帮助。由于颗粒系统具有非线性和非平衡耗散过程种类多的复杂性，基于经典物理原理的GSH理论思想能否处理这类材料，是一个仍有人怀疑的科学问题。项目将为此提供一个有意义的解答。

原则上讲颗粒物质连续力学理论应该建立在常规非平衡热力学基础上。但遗憾的是该观点并不被当前（无论工程的还是物理的）很多相关研究工作所接受。项目完成了将单元颗粒体的GSH向含液体和（或）气体的多組元混合体的推广工作。提出了这类混合体材料的"内禀热力学"建模方法（特别是自由能模型），它能成功的处理极其复杂的颗粒、液体、气体等三个組元之间的相互挤压和表面张力作用。理论的合理性得到了达西渗流，太沙基有效应力，Bishop公式，水土特征曲线等一系列实验定律的支持。另外项目还开展了铜-玻璃珠二元系统的能耗，静力与弹塑之间过渡行为的力学实验研究。这些工作结果有助于上述观点分歧的澄清和解决，推动工程领域的非饱和土连续力学理论从唯象的本构模式，提升至更加科学的物理热力学水平。