Speed of a Taylor Swimmer in Newtonian and Viscoelastic Fluids (original) (raw)
2012, Bulletin of the American Physical Society
Submitted for the DFD12 Meeting of The American Physical Society Speed of a Taylor Swimmer in Newtonian and Viscoelastic Fluids MOUMITA DASGUPTA, Clark University, BIN LIU, Brown University, HENRY FU, University of Nevada, Reno, MICHAEL BERHANU, MSC Paris Diderot University, KENNETH BREUER, THOMAS POWERS, Brown University, ARSHAD KUDROLLI, Clark University — We demonstrate that the speed of an idealized Taylor swimmer with a prescribed waveform in a viscoelastic fluid can be greater or lesser than in a Newtonian fluid depending on their rheological properties. The measurements are performed using a cylindrical sheet immersed in a fluid inside a cylindrical tank under torque free conditions with traveling waves imposed in the azimuthal direction. 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 which has a constant viscosity with shear rate. By contrast, a slower swim...
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