Physics
Speed of a swimming sheet in Newtonian and viscoelastic fluids
Document Type
Article
Abstract
We measure the swimming speed of a cylindrical version of Taylor's swimming sheet in viscoelastic fluids, and find that depending on the rheology, the speed can either increase or decrease relative to the speed in a Newtonian viscous fluid. The swimming stroke of the sheet is a prescribed propagating wave that travels along the sheet in the azimuthal direction. The measurements are performed with the sheet immersed in a fluid inside a cylindrical tank under torque-free conditions. Swimming speeds in the Newtonian case are found to be consistent with calculations using the Stokes equation. A faster swimming speed is found in a viscoelastic fluid that has a viscosity independent of shear rate. By contrast, a slower swimming speed is found with more complex shear-thinning viscoelastic fluids which have multiple relaxation time scales as well. These results are compared with calculations with Oldroyd-B fluids which find a decreasing swimming speed with Deborah number given by the product of the fluid elastic relaxation time scale and the driving frequency. © 2013 American Physical Society.
Publication Title
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
Publication Date
1-17-2013
Volume
87
Issue
1
ISSN
1539-3755
DOI
10.1103/PhysRevE.87.013015
Keywords
Newtonian fluids, viscoelastic fluids, swimming speed
Repository Citation
Dasgupta, Moumita; Liu, Bin; Fu, Henry C.; Berhanu, Michael; Breuer, Kenneth S.; Powers, Thomas R.; and Kudrolli, Arshad, "Speed of a swimming sheet in Newtonian and viscoelastic fluids" (2013). Physics. 110.
https://commons.clarku.edu/faculty_physics/110
Cross Post Location
Student Publications
