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Title: Wall-induced translation of a rotating particle in a shear-thinning fluid
Particle–wall interactions have broad biological and technological applications. In particular, some artificial microswimmers capitalize on their translation–rotation coupling near a wall to generate directed propulsion. Emerging biomedical applications of these microswimmers in complex biological fluids prompt questions on the impact of non-Newtonian rheology on their propulsion. In this work, we report some intriguing effects of shear-thinning rheology, a ubiquitous non-Newtonian behaviour of biological fluids, on the translation–rotation coupling of a particle near a wall. One particularly interesting feature revealed here is that the wall-induced translation by rotation can occur in a direction opposite to what might be intuitively expected for an object rolling on a solid substrate. We elucidate the underlying physical mechanism and discuss its implications on the design of micromachines and bacterial motion near walls in complex fluids.  more » « less
Award ID(s):
1931292 1931214
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Fluid Mechanics
Medium: X
Sponsoring Org:
National Science Foundation
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