Threedimensional 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
Motion of asymmetric bodies in twodimensional shear flow
At low Reynolds numbers, axisymmetric ellipsoidal particles immersed in a shear flow undergo periodic tumbling motions known as Jeffery orbits, with the orbit determined by the initial orientation. Understanding this motion is important for predicting the overall dynamics of a suspension. While slender fibres may follow Jeffery orbits, many such particles in nature are neither straight nor rigid. Recent work exploring the dynamics of curved or elastic fibres have found Jefferylike behaviour along with chaotic orbits, decaying orbital constants and crossstreamline drift. Most work focuses on particles with reflectional symmetry; we instead consider the behaviour of a composite asymmetric slender body made of two straight rods, suspended in a twodimensional shear flow, to understand the effects of the shape on the dynamics. We find that for certain geometries the particle does not rotate and undergoes persistent drift across streamlines, the magnitude of which is consistent with other previously identified forms of crossstreamline drift. For this class of particles, such geometrydriven crossstreamline motion may be important in giving rise to dispersion in channel flows, thereby potentially enhancing mixing.
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 Award ID(s):
 2127563
 NSFPAR ID:
 10327016
 Date Published:
 Journal Name:
 Journal of Fluid Mechanics
 Volume:
 939
 ISSN:
 00221120
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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