Shear flow of frictional spheroids : Comparison between elongated and flattened particles
Bilotto, Jacopo ; Trulsson, Martin LU
and Molinari, Jean François
(2025)
In Physical Review E
112(4).
- Abstract
The rheology of dense granular shear flows is influenced by friction and particle shape. We investigate numerically the impact of nonspherical particle geometries under shear on packing fraction, stress ratios, velocity fluctuations, force distribution, and dissipation mechanisms, for a wide range of inertial numbers, friction coefficients and aspect ratios. We obtain a regime diagram for the dissipation which shows that lentil-like (oblate) particles exhibit an extended sliding regime compared to ricelike (prolate) particles with the same degree of eccentricity. Additionally, we identify nonmonotonic behavior of slightly aspherical particles at low friction, linking it to their higher fluctuating rotational kinetic energy. We find that... (More)
The rheology of dense granular shear flows is influenced by friction and particle shape. We investigate numerically the impact of nonspherical particle geometries under shear on packing fraction, stress ratios, velocity fluctuations, force distribution, and dissipation mechanisms, for a wide range of inertial numbers, friction coefficients and aspect ratios. We obtain a regime diagram for the dissipation which shows that lentil-like (oblate) particles exhibit an extended sliding regime compared to ricelike (prolate) particles with the same degree of eccentricity. Additionally, we identify nonmonotonic behavior of slightly aspherical particles at low friction, linking it to their higher fluctuating rotational kinetic energy. We find that angular velocity fluctuations are generally reduced when particles align with the flow, except in highly frictional rolling regimes, where fluctuations collapse onto a power-law distribution and motion becomes less correlated. Moreover, for realistic friction coefficients power dissipation tends to concentrate along the major axis aligned with the flow, where slip events are more frequent. We also show that flat particles develop stronger fabric anisotropy than elongated ones, influencing macroscopic stress transmission. These findings provide new insights into the role of particle shape in granular mechanics, with implications for both industrial and geophysical applications.
(Less)
- author
- Bilotto, Jacopo
; Trulsson, Martin
LU
and Molinari, Jean François
- organization
- publishing date
- 2025-10
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review E
- volume
- 112
- issue
- 4
- article number
- 045432
- publisher
- American Physical Society
- external identifiers
-
- scopus:105022223656
- pmid:41250488
- ISSN
- 2470-0045
- DOI
- 10.1103/tj41-6qqk
- language
- English
- LU publication?
- yes
- id
- acb70212-6a5a-43ce-abd5-1a5021c04158
- date added to LUP
- 2026-02-02 11:55:00
- date last changed
- 2026-02-03 03:02:53
@article{acb70212-6a5a-43ce-abd5-1a5021c04158,
abstract = {{<p>The rheology of dense granular shear flows is influenced by friction and particle shape. We investigate numerically the impact of nonspherical particle geometries under shear on packing fraction, stress ratios, velocity fluctuations, force distribution, and dissipation mechanisms, for a wide range of inertial numbers, friction coefficients and aspect ratios. We obtain a regime diagram for the dissipation which shows that lentil-like (oblate) particles exhibit an extended sliding regime compared to ricelike (prolate) particles with the same degree of eccentricity. Additionally, we identify nonmonotonic behavior of slightly aspherical particles at low friction, linking it to their higher fluctuating rotational kinetic energy. We find that angular velocity fluctuations are generally reduced when particles align with the flow, except in highly frictional rolling regimes, where fluctuations collapse onto a power-law distribution and motion becomes less correlated. Moreover, for realistic friction coefficients power dissipation tends to concentrate along the major axis aligned with the flow, where slip events are more frequent. We also show that flat particles develop stronger fabric anisotropy than elongated ones, influencing macroscopic stress transmission. These findings provide new insights into the role of particle shape in granular mechanics, with implications for both industrial and geophysical applications.</p>}},
author = {{Bilotto, Jacopo and Trulsson, Martin and Molinari, Jean François}},
issn = {{2470-0045}},
language = {{eng}},
number = {{4}},
publisher = {{American Physical Society}},
series = {{Physical Review E}},
title = {{Shear flow of frictional spheroids : Comparison between elongated and flattened particles}},
url = {{http://dx.doi.org/10.1103/tj41-6qqk}},
doi = {{10.1103/tj41-6qqk}},
volume = {{112}},
year = {{2025}},
}