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PIV measurement of separated flow in a square channel with streamwise periodic ribs on one wall

Wang, Lei LU ; Hejcik, J. and Sundén, Bengt LU (2007) In Journal of Fluids Engineering 129(7). p.834-841
Abstract
In. this study, particle image velocimetry (PIV) is used to investigate the physical process of separated flow in a square channel roughened with periodically transverse ribs on one wall. The ribs obstruct the channel by 15% of its height and are arranged 12 rib heights apart. The Reynolds number based on the bulk-mean velocity and the corresponding hydraulic diameter of the channel, is fixed at 22,000. Assuming flow periodicity in the streamwise direction, the investigated domain is between two consecutive ribs. The emphasis of this study is to give some insight into the turbulence mechanism associated with separation, reattachment, and subsequent redevelopment. Results are included for mean velocity, friction coefficient, vorticity... (More)
In. this study, particle image velocimetry (PIV) is used to investigate the physical process of separated flow in a square channel roughened with periodically transverse ribs on one wall. The ribs obstruct the channel by 15% of its height and are arranged 12 rib heights apart. The Reynolds number based on the bulk-mean velocity and the corresponding hydraulic diameter of the channel, is fixed at 22,000. Assuming flow periodicity in the streamwise direction, the investigated domain is between two consecutive ribs. The emphasis of this study is to give some insight into the turbulence mechanism associated with separation, reattachment, and subsequent redevelopment. Results are included for mean velocity, friction coefficient, vorticity thickness, Reynolds shear stress, anisotropy parameter and production of turbulent kinetic energy and shear stress. Based on the two-point correlation profiles, Taylor microscales are derived to reveal the sizes of the turbulence structure in the longitudinal and lateral directions. Moreover Galilean decomposition is applied to the instantaneous velocity fields. The result shows that the separated shear layer is dominated by the large-scale, unsteady vortical structures. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
PIV, turbulence properties, separated flow
in
Journal of Fluids Engineering
volume
129
issue
7
pages
834 - 841
publisher
American Society Of Mechanical Engineers (ASME)
external identifiers
  • WOS:000248070900003
  • Scopus:34547652821
ISSN
0098-2202
DOI
10.1115/1.2742723
language
English
LU publication?
yes
id
6ba96262-cf5f-44d5-88a5-52039e27ccfb (old id 586468)
date added to LUP
2008-02-14 11:25:06
date last changed
2016-10-13 04:33:39
@misc{6ba96262-cf5f-44d5-88a5-52039e27ccfb,
  abstract     = {In. this study, particle image velocimetry (PIV) is used to investigate the physical process of separated flow in a square channel roughened with periodically transverse ribs on one wall. The ribs obstruct the channel by 15% of its height and are arranged 12 rib heights apart. The Reynolds number based on the bulk-mean velocity and the corresponding hydraulic diameter of the channel, is fixed at 22,000. Assuming flow periodicity in the streamwise direction, the investigated domain is between two consecutive ribs. The emphasis of this study is to give some insight into the turbulence mechanism associated with separation, reattachment, and subsequent redevelopment. Results are included for mean velocity, friction coefficient, vorticity thickness, Reynolds shear stress, anisotropy parameter and production of turbulent kinetic energy and shear stress. Based on the two-point correlation profiles, Taylor microscales are derived to reveal the sizes of the turbulence structure in the longitudinal and lateral directions. Moreover Galilean decomposition is applied to the instantaneous velocity fields. The result shows that the separated shear layer is dominated by the large-scale, unsteady vortical structures.},
  author       = {Wang, Lei and Hejcik, J. and Sundén, Bengt},
  issn         = {0098-2202},
  keyword      = {PIV,turbulence properties,separated flow},
  language     = {eng},
  number       = {7},
  pages        = {834--841},
  publisher    = {ARRAY(0xb47eb30)},
  series       = {Journal of Fluids Engineering},
  title        = {PIV measurement of separated flow in a square channel with streamwise periodic ribs on one wall},
  url          = {http://dx.doi.org/10.1115/1.2742723},
  volume       = {129},
  year         = {2007},
}