Granular materials, such as grains, snow, sand, coal, etc., can flow like fluids or rapidly revert to a solid state (as in a rock and snow avalanches). The understanding of such dense granular matter lags far behind the knowledge of normal matter such as solids, liquids, and gases. This Small Grant for Exploratory Research supports a project with the goal of developing a technique that for the first time should permit the study of the details of how force is distributed in a three dimensional granular assembly at rest. A successful result will contribute significantly to solving many major practical problems in handling and processing granular materials, as well as in dealing with stability of soil and the behavior of landslides. At the same time, this is an excellent project for competent graduate students providing challenges in physics, electrical and mechanical design and construction, and writing software.
This Small Grant for Exploratory Research supports a collaboration between researchers at a research university and a not-for-profit organization. The project is directed towards determining forces between grains in fully three-dimensional granular materials using Magnetic Resonance Elastography (MRE), which is a form of Magnetic Resonance Imaging. Granular materials present one of the greatest current challenges in statistical physics, particularly in the dense phases where particles remain in contact for extended periods of time. The way in which forces are carried through these materials is of fundamental interest scientifically. Knowledge of how these forces are carried would inform technical processes ranging from the handling of bulk industrial particulates to pharmaceutical processing. Although there have been extensive theoretical developments that attempt to model this state, current experimental techniques have not been able to access the forces between particles within a fully three-dimensional sample. This project would provide for the first time such information and establish the nature of force structures in 3D granular materials. The graduate students involved will learn skills relevant to physics, electrical and mechanical design and construction, and writing software. They will also be exposed to research at a not-for-profit organization.