Back to Search
Start Over
On the relative rotational motion between rigid fibers and fluid in turbulent channel flow
- Source :
- Physics of Fluids. 28:013301
- Publication Year :
- 2016
- Publisher :
- AIP Publishing, 2016.
-
Abstract
- In this study, the rotation of small rigid fibers relative to the surrounding fluid in wall-bounded turbulence is examined by means of direct numerical simulations coupled with Lagrangian tracking. Statistics of the relative (fiber-to-fluid) angular velocity, referred to as slip spin in the present study, are evaluated by modelling fibers as prolate spheroidal particles with Stokes number, St, ranging from 1 to 100 and aspect ratio, λ, ranging from 3 to 50. Results are compared one-to-one with those obtained for spherical particles (λ = 1) to highlight effects due to fiber length. The statistical moments of the slip spin show that differences in the rotation rate of fibers and fluid are influenced by inertia, but depend strongly also on fiber length: Departures from the spherical shape, even when small, are associated with an increase of rotational inertia and prevent fibers from passively following the surrounding fluid. An increase of fiber length, in addition, decouples the rotational dynamics of a fiber from its translational dynamics suggesting that the two motions can be modelled independently only for long enough fibers (e.g., for aspect ratios of order ten or higher in the present simulations).
- Subjects :
- Fluid Flow and Transfer Processes
Physics
Turbulence
Mechanical Engineering
media_common.quotation_subject
Computational Mechanics
Rotation around a fixed axis
Angular velocity
Slip (materials science)
Mechanics
Moment of inertia
Condensed Matter Physics
Inertia
01 natural sciences
010305 fluids & plasmas
Open-channel flow
Mechanics of Materials
0103 physical sciences
010306 general physics
Stokes number
media_common
Subjects
Details
- ISSN :
- 10897666 and 10706631
- Volume :
- 28
- Database :
- OpenAIRE
- Journal :
- Physics of Fluids
- Accession number :
- edsair.doi.dedup.....2016470a58c014cffce8774af0dc6b3d
- Full Text :
- https://doi.org/10.1063/1.4937757