Statistical and Dynamical Properties of Spherical and Non-Spherical Granular Materials

球形和非球形颗粒材料的统计和动力学特性

• 批准号: 0605664
• 负责人: Arshad Kudrolli
• 金额: $ 32.7万
• 依托单位: Clark University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-06-15 至 2010-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0605664&HistoricalAwards=false
• 关键词: Statistical; Dynamical; Properties; Spherical; Non

Non-technical abstract: Experiments with high-speed imaging techniques will be conducted to understand the impact of particle shape and magnetization on the properties of granular matter. These studies are important because granular materials are ubiquitous constituents in industrial processes (e.g., food grain silos, fertilizers) and natural phenomena (e.g., mudslides), and yet no fundamental theory is currently available to describe them. We propose to test and develop mathematical model for granular matter over a wide range of parameters. Furthermore, grains come in all shapes and it is important to incorporate its impact into models that describe how different kinds of grains organize and flow. The proposed work will have significant impact on graduate student training. The grant will enhance research experience of undergraduate students in the laboratory, and the research will be also adapted into a modern course on mechanics. Local community will be exposed to the research via topical workshops, and by the researchers speaking at neighboring high schools to excite interests in the sciences. Technical abstract: The statistical and dynamical properties of spherical and non-spherical vibro-fluidized granular materials will be investigated with high-speed imaging techniques. The impact of particle shape will be the main focus and will be studied using vibrated rods, dimers, and polymers composed of linked bead chains. The impact of dissipation and anisotropic interactions on the self-assembly of novel structures and global dynamics will be probed. In thermal systems, long-range order is observed in oblate particles leading to nematic and smectic states which is said to simplify analysis. Whether interparticle friction in granular matter suppresses uniform exploration of phase space, as assumed by such approaches, is an open question. The effect of magnetization and long-range interaction on the self-assembly will be also studied, and compared with the dipolar hard sphere model developed for ferro-fluids. The extent to which equilibrium statistical physics and entropic considerations apply to dissipative granular systems will be investigated. Such experiments are interesting in the context of finding effective strategies for self-assembly in nano-particles as well. Besides developing fundamental knowledge on materials which need to be handled more efficiently in industry, the proposed work will directly support training of graduate students, enhance research experience of undergraduate students, impact development of a modern mechanics course, and impact the local community by engaging students in neighboring high schools via lectures.

非技术摘要：将进行高速成像技术实验，以了解颗粒形状和磁化强度对颗粒物质特性的影响。这些研究很重要，因为颗粒材料是工业过程（例如粮食筒仓、化肥）和自然现象（例如泥石流）中普遍存在的成分，但目前还没有可用的基本理论来描述它们。我们建议在广泛的参数范围内测试和开发颗粒物质的数学模型。此外，颗粒有各种形状，将其影响纳入描述不同种类颗粒如何组织和流动的模型中非常重要。拟议的工作将对研究生培养产生重大影响。该赠款将增强本科生在实验室的研究经验，该研究还将改编成现代力学课程。当地社区将通过专题研讨会以及研究人员在邻近高中的演讲来接触这项研究，以激发对科学的兴趣。技术摘要：将利用高速成像技术研究球形和非球形振动流化颗粒材料的统计和动力学特性。颗粒形状的影响将是主要焦点，并将使用振动棒、二聚体和由连接珠链组成的聚合物进行研究。将探讨耗散和各向异性相互作用对新型结构自组装和全局动力学的影响。在热系统中，在扁圆粒子中观察到长程有序，导致向列和近晶态，据说可以简化分析。粒状物质中的颗粒间摩擦是否会抑制相空间的均匀探索（如此类方法所假设的那样）是一个悬而未决的问题。还将研究磁化和长程相互作用对自组装的影响，并与为铁磁流体开发的偶极硬球模型进行比较。将研究平衡统计物理和熵考虑因素在多大程度上适用于耗散颗粒系统。在寻找纳米粒子自组装的有效策略方面，此类实验也很有趣。除了发展工业中需要更有效处理的材料的基础知识外，拟议的工作还将直接支持研究生的培训，增强本科生的研究经验，影响现代力学课程的发展，并通过讲座吸引邻近高中的学生来影响当地社区。