Speed of a swimming sheet in Newtonian and viscoelastic fluids

被引：60

作者：

Dasgupta, Moumita ^{[1
]}

Liu, Bin ^{[2
]}

Fu, Henry C. ^{[2
,3
]}

Berhanu, Michael ^{[1
,4
]}

Breuer, Kenneth S. ^{[2
]}

Powers, Thomas R. ^{[2
,5
]}

Kudrolli, Arshad ^{[1
]}

机构：

[1] Clark Univ, Dept Phys, Worcester, MA 01610 USA

[2] Brown Univ, Sch Engn, Providence, RI 02912 USA

[3] Univ Nevada, Dept Mech Engn, Reno, NV 89509 USA

[4] Univ Paris Diderot, CNRS, UMR 7057, F-75013 Paris, France

[5] Brown Univ, Dept Phys, Providence, RI 02912 USA

来源：

PHYSICAL REVIEW E | 2013年 / 87卷 / 01期

基金：

美国国家科学基金会;

关键词：

RELAXATION; MODEL;

D O I：

10.1103/PhysRevE.87.013015

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

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. DOI: 10.1103/PhysRevE.87.013015

引用

页数：7

共 14 条

[1] NONLINEAR VISCOELASTIC MODEL WITH STRUCTURE-DEPENDENT RELAXATION-TIMES .1. BASIC FORMULATION [J].