Tumbling of a rigid rod in a shear flow
| Autor: | J. M. J. van Leeuwen, Henk W. J. Blöte |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
Statistics and Probability
Physics Statistical Mechanics (cond-mat.stat-mech) Shear force FOS: Physical sciences Statistical and Nonlinear Physics Mechanics Fick's laws of diffusion Shear rate Physics::Fluid Dynamics Flow (mathematics) Master equation Weissenberg number Statistics Probability and Uncertainty Shear flow Stationary state Condensed Matter - Statistical Mechanics |
| Popis: | The tumbling of a rigid rod in a shear flow is analyzed in the high viscosity limit. Following Burgers, the Master Equation is derived for the probability distribution of the orientation of the rod. The equation contains one dimensionless number, the Weissenberg number, which is the ratio of the shear rate and the orientational diffusion constant. The equation is solved for the stationary state distribution for arbitrary Weissenberg numbers, in particular for the limit of high Weissenberg numbers. The stationary state gives an interesting flow pattern for the orientation of the rod, showing the interplay between flow due to the driving shear force and diffusion due to the random thermal forces of the fluid. The average tumbling time and tumbling frequency are calculated as a function of the Weissenberg number. A simple cross-over function is proposed which covers the whole regime from small to large Weissenberg numbers. 22 pages, 9 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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