Is the zero Reynolds number approximation valid for ciliary flows?

Journal Article (2019)
Author(s)

D. Wei (TU Delft - BN/Marie-Eve Aubin-Tam Lab)

Parviz G. Ghoddoosi Dehnavi (TU Delft - Fluid Mechanics)

ME Aubin-Tam (TU Delft - BN/Marie-Eve Aubin-Tam Lab)

Daniel See Wai Tam (TU Delft - Fluid Mechanics)

Research Group
BN/Marie-Eve Aubin-Tam Lab
Copyright
© 2019 D. Wei, P. Ghoddoosi Dehnavi, M.E. Aubin-Tam, D.S.W. Tam
DOI related publication
https://doi.org/10.1103/PhysRevLett.122.124502
More Info
expand_more
Publication Year
2019
Language
English
Copyright
© 2019 D. Wei, P. Ghoddoosi Dehnavi, M.E. Aubin-Tam, D.S.W. Tam
Research Group
BN/Marie-Eve Aubin-Tam Lab
Issue number
12
Volume number
122
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

Stokes equations are commonly used to model the hydrodynamic flow around cilia on the micron scale. The validity of the zero Reynolds number approximation is investigated experimentally with a flow velocimetry approach based on optical tweezers, which allows the measurement of periodic flows with high spatial and temporal resolution. We find that beating cilia generate a flow, which fundamentally differs from the stokeslet field predicted by Stokes equations. In particular, the flow velocity spatially decays at a faster rate and is gradually phase delayed at increasing distances from the cilia. This indicates that the quasisteady approximation and use of Stokes equations for unsteady ciliary flow are not always justified and the finite timescale for vorticity diffusion cannot be neglected. Our results have significant implications in studies of synchronization and collective dynamics of microswimmers.

Files

License info not available