Mechanics of Anisotropic Granular Materials

各向异性颗粒材料力学

• 批准号: RGPIN-2018-04573
• 负责人: Nadler, Ben
• 金额: $ 2.33万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=684325
• 关键词: Mechanics; Anisotropic; Granular; Materials

The mechanics of granular materials has diverse applications ranging from the efficient transportation and sorting of grains to the modeling of landslides and avalanches. Better understanding, e.g. through accurate models, is necessary for future improvements of these processes and the control of landslides and avalanches. Grains show a very complex mechanical response that can transition from a static-state into a dynamic flow.***All naturally occurring grains, including sand, rocks or pebbles, consist of non-spherical (shaped) grains. Also in industry, most grains are non-spherical, in particular in agriculture and food processing where crops have elongated or flattened shapes, or in pharmaceutics with pills and drug capsules.***The microstructure and ability of shaped grains to align themselves provides an added degree of complexity. The mechanical properties of shaped grains vary significantly with the microstructure alignment of the grains which gives rise to direction dependent mechanical properties (anisotropy).***This research program will develop mathematical models for shaped grains to advance our fundamental understanding of the mechanics of shaped grains which is currently not well understood by the Engineering and Physics communities. The developed models will be compared with a range of experiments conducted at the DynamiX: X-ray tomography and the Particles and Grains Laboratories at the University of Sydney, Australia.***Very little work is published in the literature studying the mechanics of shaped grains and, to our knowledge, no mathematical model has been developed as of yet. Hence, the proposed research program will explore research directions which are novel, not well understood and very little studied.***The main novel idea in this research program is to explicitly account for the microstructure reflecting the grain alignment in the mathematical models using anisotropic constitutive laws to accurately describe the mechanical properties. The main two challenges are to understand the mechanism of shaped grains alignment and the relationship between the mechanical properties and the microstructure arrangement.***The mechanics of shaped grains has many applications in transportation, sorting and storing of granular materials in agriculture (crops), food processing and the pharmaceutics (pills and drug capsules) industries. The results of this research program will be made available to these industries to improve their process as well as industries designing and manufacturing supporting machinery. It is anticipated that the insights and the developed mathematical models will have substantial impact both scientifically and on the many industries processing grain. It is also anticipated that this research program will have contribution to research on other systems involving the mechanics of non-spherical particles such as modeling red blood cells flow.

颗粒材料的力学有着广泛的应用，从有效地运输和分选谷物到模拟滑坡和雪崩。更好地了解，例如通过准确的模型，对于今后改进这些过程和控制滑坡和雪崩是必要的。颗粒表现出非常复杂的机械响应，可以从静态转变为动态流动。*所有自然形成的颗粒，包括沙、岩石或鹅卵石，都由非球形(形状)颗粒组成。同样在工业中，大多数谷物是非球形的，特别是在农业和食品加工业中，作物具有拉长或扁平的形状，或者在制药行业中，如药丸和药物胶囊。*成型谷物的微观结构和自身排列的能力增加了复杂性。成型颗粒的机械性能随着颗粒的微结构排列而显著不同，这导致了方向相关的机械性能(各向异性)。*本研究计划将开发成型颗粒的数学模型，以促进我们对成型颗粒力学的基本理解，目前工程界和物理界对此还不是很了解。所开发的模型将与澳大利亚悉尼大学Dynamix：X射线断层成像和粒子和颗粒实验室进行的一系列实验进行比较。*研究成型颗粒的力学的文献发表的工作很少，据我们所知，到目前为止还没有建立数学模型。因此，提出的研究计划将探索新的、不被很好地理解和很少研究的研究方向。*本研究计划的主要创新思想是使用各向异性本构关系在数学模型中显式地解释反映晶粒取向的微观结构，以准确地描述力学性能。主要的两个挑战是了解颗粒定形的机理和机械性能与微结构排列之间的关系。*颗粒的力学在农业(农作物)、食品加工和制药(药丸和药物胶囊)工业中的颗粒材料的运输、分选和储存中有许多应用。这项研究计划的结果将提供给这些行业，以改进其工艺以及设计和制造辅助机械的行业。预计这些见解和开发的数学模型将对科学和许多粮食加工行业产生重大影响。预计这项研究计划将对其他涉及非球形粒子力学的系统的研究做出贡献，例如对红细胞流动进行建模。