Dupuis, Victor;
Trevisson, Michele;
Wunder, Sina;
Mclelland, Stuart;
Moulin, Frederic Y;
Chagot, Loic;
Eiff, Olivier;
(2023)
Effect of a canopy patch made of streamwise-oriented plates on turbulence in an open-channel flow.
Environmental Fluid Mechanics
, 23
pp. 1341-1357.
10.1007/s10652-023-09949-7.
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Abstract
The paper examines the flow through a highly porous canopy patch made of streamwise-oriented thin plates arranged in a staggered configuration and placed in a rough-bed open channel. This patch geometry contrasts with the patches made of bluff bodies, which are nearly exclusively used in the literature. Particle Image Velocimetry was used to measure the flow upstream, within and downstream of the patch. The canopy patch has the effect of drastically reducing the turbulence level of the incoming flow, especially the turbulence shear stress, which is reduced by 85%. Spectral analysis of the velocity shows that the reduction in turbulent kinetic energy occurs at all length scales. Yet, at the entrance of the patch, the energy from the smallest scales up to the scale of the water surface increases. This suggests a spectral shortcut mechanism by which the large-scale structures of the incoming flow are disintegrated by the group of plates instead of decaying through the energy cascade. The increased small-scale turbulent energy then dissipates through the patch.
| Type: | Article |
|---|---|
| Title: | Effect of a canopy patch made of streamwise-oriented plates on turbulence in an open-channel flow |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1007/s10652-023-09949-7 |
| Publisher version: | http://dx.doi.org/10.1007/s10652-023-09949-7 |
| Language: | English |
| Additional information: | This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. |
| Keywords: | Canopy patch, Porous obstacle, Spectral shortcut, Turbulence reduction |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Chemical Engineering |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10186509 |
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