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A numerical study on orientational arrest and size segregation of dense particle flows using discrete element modeling

Yousefian, Zakiyeh LU (2023)
Abstract
The thesis focuses on studying dense particle flows, which are either dry or submerged in a Newtonian fluid through two dimensional numerical simulations using the discrete element method (DEM). The First paper deals with dense suspensions in viscous regime under oscillatory planar shear. We found that having an oscillatory shear can help reducing the viscosity of the suspension. Also, in the frictional case oscillation can increase the suspension’s shear jamming packing fraction. Furthermore, at small oscillatory strains, frictionless ellipses become dynamically arrested in their initial orientational configuration. In the second paper, we studied size segregation in a bi-disperse mixture of big and small discs. We applied an iterative... (More)
The thesis focuses on studying dense particle flows, which are either dry or submerged in a Newtonian fluid through two dimensional numerical simulations using the discrete element method (DEM). The First paper deals with dense suspensions in viscous regime under oscillatory planar shear. We found that having an oscillatory shear can help reducing the viscosity of the suspension. Also, in the frictional case oscillation can increase the suspension’s shear jamming packing fraction. Furthermore, at small oscillatory strains, frictionless ellipses become dynamically arrested in their initial orientational configuration. In the second paper, we studied size segregation in a bi-disperse mixture of big and small discs. We applied an iterative force measurement technique to find the restoring/segregation force on big and small particles in the system when we have constant or linearly increasing vertical gravity. Our method works equivalently well as a previously introduced method for the case of having a constant vertical gravitational field while it can find the restoring force for the case of linearly increasing gravity whereas the other method fails to measure the force. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • professor Revstedt, Johan, Lund University
organization
publishing date
type
Thesis
publication status
published
subject
keywords
particle flows, dense suspensions, granular materials
publisher
Lund University (Media-Tryck)
defense location
Lecture hall C, Kemicentrum, Naturvetarvägen 14, 221 00 Lund
defense date
2024-01-26 09:30:00
ISBN
978-91-7422-964-6
978-91-7422-965-3
project
numerical study of particle flows
language
English
LU publication?
yes
id
4ec0e89a-1443-49a7-a6a1-2b7d30d3e453
date added to LUP
2024-01-05 00:20:28
date last changed
2024-01-17 07:54:12
@misc{4ec0e89a-1443-49a7-a6a1-2b7d30d3e453,
  abstract     = {{The thesis focuses on studying dense particle flows, which are either dry or submerged in a Newtonian fluid through two dimensional numerical simulations using the discrete element method (DEM). The First paper deals with dense suspensions in viscous regime under oscillatory planar shear. We found that having an oscillatory shear can help reducing the viscosity of the suspension. Also, in the frictional case oscillation can increase the suspension’s shear jamming packing fraction. Furthermore, at small oscillatory strains, frictionless ellipses become dynamically arrested in their initial orientational configuration. In the second paper, we studied size segregation in a bi-disperse mixture of big and small discs. We applied an iterative force measurement technique to find the restoring/segregation force on big and small particles in the system when we have constant or linearly increasing vertical gravity. Our method works equivalently well as a previously introduced method for the case of having a constant vertical gravitational field while it can find the restoring force for the case of linearly increasing gravity whereas the other method fails to measure the force.}},
  author       = {{Yousefian, Zakiyeh}},
  isbn         = {{978-91-7422-964-6}},
  keywords     = {{particle flows; dense suspensions; granular materials}},
  language     = {{eng}},
  month        = {{12}},
  note         = {{Licentiate Thesis}},
  publisher    = {{Lund University (Media-Tryck)}},
  title        = {{A numerical study on orientational arrest and size segregation of dense particle flows using discrete element modeling}},
  year         = {{2023}},
}