Hare, C and Ghadiri, M (2013) The influence of aspect ratio and roughness on flowability. In: AIP Conference Proceedings. International Conference on Micromechanics of Granular Media, 08-12 Jul 2013, Sydney, Australia. American Institute of Physics , 887 - 890. ISBN 9780735411661
Abstract
Poor flowability hampers particle processing in many instances; causing a reduction in process efficiency, increased manufacturing costs and leading to excessive waste. The resistance of powders to flow can arise from a number of particle properties, such as cohesion, friction, shape and roughness. The objective of this work is to determine to what extent the flowability of powders is affected by their particle shape and roughness. The Distinct Element Method (DEM) is used to precisely control the shape and roughness of the particles. Needle-like particles are represented by the method of overlapping spheres, introduced by Favier et al. (1999). The fractional overlap of these spheres is varied, along with the number of spheres per particle, to produce particles with ranges of roughness and aspect ratio, respectively. The flowability of these particles is assessed by simulating two systems: a standard shear box, and indentation of a powder bed with a spherical indenter-introduced by Hassanpour and Ghadiri (2007). The particles are generated with a random orientation and allowed to settle under gravity before they are consolidated by a platen to a desired stress. The results show that particles with a large aspect ratio experience reduced shear stresses. This behaviour may be caused by particles aligning, thus allowing them to slide past one another more easily. An increase in particle roughness promotes interlocking, for a given aspect ratio rougher particles are shown to experience increased shear stresses. This work provides a robust analysis of the influence of aspect ratio and roughness on the flowability of powders, thus allowing the flowability of real materials to be better understood.
Metadata
Item Type: | Proceedings Paper |
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Authors/Creators: |
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Keywords: | DEM; Flowability; Particle Shape; Roughness; Shear |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Institute for Particle Science and Engineering (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 20 Nov 2014 12:04 |
Last Modified: | 19 Dec 2022 13:28 |
Published Version: | http://dx.doi.org/10.1063/1.4812074 |
Status: | Published |
Publisher: | American Institute of Physics |
Refereed: | Yes |
Identification Number: | 10.1063/1.4812074 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:80931 |