Imperial College London
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DrPaulBruce

Faculty of Engineering, Department of Aeronautics

Reader in High-Speed Aerodynamics
 
 
 
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Contact

 

+44 (0)20 7594 5048p.bruce

 
 
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Location

 

333City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Rodriguez-Lopez:2017:10.1063/1.4995307,
author = {Rodriguez-Lopez, E and Bruce, PJK and Buxton, ORH},
doi = {10.1063/1.4995307},
journal = {Physics of Fluids},
title = {Flow characteristics and scaling past highly porous wall-mounted fences},
url = {http://dx.doi.org/10.1063/1.4995307},
volume = {29},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - An extensive characterization of the flow past wall-mounted highly porous fences based on single-and multi-scale geometries has been performed using hot-wire anemometry in a low-speed windtunnel. Whilst drag properties (estimated from the time-averaged momentum equation) seem to bemostly dependent on the grids’ blockage ratio; wakes of different size and orientation bars seem togenerate distinct behaviours regarding turbulence properties. Far from the near-grid region, the flowis dominated by the presence of two well-differentiated layers: one close to the wall dominated bythe near-wall behaviour and another one corresponding to the grid’s wake and shear layer, originatingfrom between this and the freestream. It is proposed that the effective thickness of the wall layer canbe inferred from the wall-normal profile of root-mean-square streamwise velocity or, alternatively,from the wall-normal profile of streamwise velocity correlation. Using these definitions of wall-layerthickness  enables  us  to  collapse  different  trends  of  the  turbulence  behaviour  inside  this  layer.  Inparticular, the root-mean-square level of the wall shear stress fluctuations, longitudinal integral lengthscale, and spanwise turbulent structure is shown to display a satisfactory scaling with this thicknessrather than with the whole thickness of the grid’s wake. Moreover, it is shown that certain gridsdestroy the spanwise arrangement of large turbulence structures in the logarithmic region, which arethen re-formed after a particular streamwise extent. It is finally shown that for fences subject to aboundary layer of thickness comparable to their height, the effective thickness of the wall layer scaleswith the incoming boundary layer thickness. Analogously, it is hypothesized that the growth rate ofthe internal layer is also partly dependent on the incoming boundary layer thickness.
AU  - Rodriguez-Lopez,E
AU  - Bruce,PJK
AU  - Buxton,ORH
DO  - 10.1063/1.4995307
PY  - 2017///
SN  - 1070-6631
TI  - Flow characteristics and scaling past highly porous wall-mounted fences
T2  - Physics of Fluids
UR  - http://dx.doi.org/10.1063/1.4995307
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000406765200030&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/50578
VL  - 29
ER  -
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