The Open UniversitySkip to content
 

Orientation statistics of small particles in turbulence

Pumir, Alain and Wilkinson, Michael (2011). Orientation statistics of small particles in turbulence. New J. Phys., 13 093030.

DOI (Digital Object Identifier) Link: http://dx.doi.org/10.1088/1367-2630/13/9/093030
Google Scholar: Look up in Google Scholar

Abstract

The statistics of the alignment of axisymmetric microscopic particles in fully developed turbulent flow is studied numerically and theoretically. Direct numerical simulations (DNS) of turbulent flows demonstrate that rod-like particles are more strongly aligned with the vorticity vector than with the principal strain axis. To elucidate this property, we compare the evolution obtained in a turbulent flow with a simpler model, where the velocity gradient of the flow is replaced by a fluctuating random matrix, whose temporal correlations reproduce the properties observed in DNS. In contrast with the DNS results, this model exhibits a strong alignment of the rods with the direction of the fastest stretching of the symmetric part of the random matrix. We argue that the correlation between the rod axis and the vorticity vector arises from similarities between the equations of motion governing these quantities.


Item Type: Journal Article
Copyright Holders: 2011 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft
Academic Unit/Department: Mathematics, Computing and Technology > Mathematics and Statistics
Item ID: 30918
Depositing User: Michael Wilkinson
Date Deposited: 06 Jan 2012 15:34
Last Modified: 30 Nov 2012 16:50
URI: http://oro.open.ac.uk/id/eprint/30918
Share this page:

Altmetrics

Scopus Citations

Actions (login may be required)

View Item
Report issue / request change

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340   general-enquiries@open.ac.uk