<abstract xmlns="http://www.w3.org/1999/xhtml"><p> The study presents experimental investigations of spatial turbulence intensity and scales of turbulent eddies (macroeddies) in a rectangular channel and the impact of the hydraulic jump on their vertical and streamwise distributions over a flat and scoured bed. The results of four tests and two different discharge rates are presented. Intensive mixing caused by the hydraulic jump has an impact on the instantaneous velocity, turbulence intensity and sizes of macroeddies, as well as their vertical and longitudinal distributions along the channel. The largest differences in turbulence characteristics were reported directly after the hydraulic jump, above the eroded bed. The interaction between the stream of the increased turbulence and the bed is a direct cause of formation of scour downstream water structures, which has a great effect on overall flow characteristics. The scour hole that arose downstream the jump moderated, in a small degree, the turbulence intensity at its end. Just next to the hydraulic jump only the small longitudinal relative sizes of macroeddies were present, while at the end of the analyzed reach, downstream of the scour, the relative scale reached around 1.5 depth of the stream.</p></abstract>

The study presents experimental investigations of spatial turbulence intensity and scales of turbulent eddies (macroeddies) in a rectangular channel and the impact of the hydraulic jump on their vertical and streamwise distributions over a flat and scoured bed. The results of four tests and two different discharge rates are presented. Intensive mixing caused by the hydraulic jump has an impact on the instantaneous velocity, turbulence intensity and sizes of macroeddies, as well as their vertical and longitudinal distributions along the channel. The largest differences in turbulence characteristics were reported directly after the hydraulic jump, above the eroded bed. The interaction between the stream of the increased turbulence and the bed is a direct cause of formation of scour downstream water structures, which has a great effect on overall flow characteristics. The scour hole that arose downstream the jump moderated, in a small degree, the turbulence intensity at its end. Just next to the hydraulic jump only the small longitudinal relative sizes of macroeddies were present, while at the end of the analyzed reach, downstream of the scour, the relative scale reached around 1.5 depth of the stream.

Turbulence intensity and spatial scales of turbulence after hydraulic jump over scour hole in rectangular channel

Journal of Hydrology and Hydromechanics

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

The study presents experimental investigations of spatial turbulence intensity and scales of turbulent eddies (macroeddies) in a rectangular channel and the...

Turbulence intensity and spatial scales of turbulence after hydraulic jump over scour hole in rectangular channel

Publié en ligne: 07 nov. 2017

Pages: 385 - 394

Reçu: 23 févr. 2016

Accepté: 25 nov. 2016

DOI: https://doi.org/10.1515/johh-2017-0026

Mots clés
Turbulent intensity, Eddies, Hydraulic jump, Scour hole, Rectangular channel

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Turbulence intensity and spatial scales of turbulence after hydraulic jump over scour hole in rectangular channel

Publié en ligne: 07 nov. 2017

Pages: 385 - 394

Reçu: 23 févr. 2016

Accepté: 25 nov. 2016

DOI: https://doi.org/10.1515/johh-2017-0026

Mots clésTurbulent intensity, Eddies, Hydraulic jump, Scour hole, Rectangular channel

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Mots clés
Turbulent intensity, Eddies, Hydraulic jump, Scour hole, Rectangular channel