Three-dimensional dynamics of flexible fibers in shear flow are studied numerically, with a qualitative comparison to experiments. Initially, the fibers are straight, with different orientations with respect to the flow. By changing the rotation speed of a shear rheometer, we change the ratio
Vorticity alignment of rigid fibers in an oscillatory shear flow: Role of confinement
Rigid fibers suspended in a viscous, Newtonian fluid at high concentrations can be aligned in the direction perpendicular to the flow-gradient plane (vorticity direction) by applying an oscillatory shear flow. A simple model, which considers only excluded volume and self-mobilities, can accurately predict the orientation distributions measured in experiments by Franceschini et al. [“Transverse alignment of fibers in a periodically sheared suspension: An absorbing phase transition with a slowly varying control parameter,” Phys. Rev. Lett. 107, 250603 (2011)10.1103/PhysRevLett.107.250603]. Furthermore, simulations reveal that the alignment of the fibers in the vorticity direction depends strongly on the presence of the bounding walls.
more » « less- PAR ID:
- 10426522
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Physics of Fluids
- Volume:
- 24
- Issue:
- 12
- ISSN:
- 1070-6631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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