Collisional flows of oriented granular materials

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In this research project we propose to develop highly accurate rheological models for aspherical oriented grains that will be used to design efficient processes involving transportation and sorting of such granular materials. Highly accurate rheological models for grains have been successfully used for many applications involving granular processing, yet these models are limited to spherical grains ignoring the shape and orientations of the grains. However, naturally occurring granular materials are composed of aspherical particles; sand particles, rocks, or pebbles in the mining sector, in the agriculture and food processing industries where grains have elongated or flattened shapes, or in pharmaceutics with pills and drug capsules. The efficient processing of these materials relays on steady flow of the grains and avoiding jamming. Hence, availability of highly accurate rheological models for aspherical oriented grains is essential for the design of processes and equipment to efficiently process these materials. The models developed in this project will provide accurate and cost-effective computational tools to the related academic and industrial communities to simulate and study realistic granular flows, which are used in many industries in Canada and internationally. To achieve these goals, we will generalize the granular kinetic theory models, which are very successfully used to model collisional dense flows of spherical grains, to aspherical oriented grains. The flow of aspherical oriented grains shows a very complex rheological response as it is governed by the microstructure contact and collision and by the orientation and alignment of the grains. Currently, the modes developed for aspherical oriented grains use phenomenological parameters that are determined by costly empirical data. However, these parameters can be determined directly by using kinetic theory, avoiding the use of expensive experiments or microscopic computer simulations. The ability to reduce the required cost will provide efficient and effective tool to simulate large-scale aspherical oriented granular flows.