Zhang, X;
Simons, R;
(2019)
Experimental investigation on the structure of turbulence in the bottom wave-current boundary layers.
Coastal Engineering
, 152
, Article 103511. 10.1016/j.coastaleng.2019.103511.
Preview |
Text
Simons Paper -- Final Version.pdf - Accepted Version Download (2MB) | Preview |
Abstract
This paper presents insights into the structure of turbulence in combined wave-current boundary layers, based on experiments performed in flumes of different scale using Particle Image Velocimetry and hydrogen bubble visualisation. Flow conditions covered a range of wave frequencies, wave amplitudes and mean flow conditions. Results show that the spacing between turbulent streaks varies periodically with the passage of each wave, increasing when the flow accelerates and decreasing when the flow decelerates. A new formula has been put forward, relating the streak spacing variation and the wave-induced orbital displacements. The near-wall flow structure suggests a rhythmic pattern in terms of the velocity gradients across the flume. Waves with higher frequencies and larger amplitudes lead to a greater reduction of mean streak spacing, together with a greater increase of the maximum Reynolds shear stress induced by ejections. These results can be useful for better predictions of the hydrodynamics and sediment transport in combined wave-current flows.
| Type: | Article |
|---|---|
| Title: | Experimental investigation on the structure of turbulence in the bottom wave-current boundary layers |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1016/j.coastaleng.2019.103511 |
| Publisher version: | https://doi.org/10.1016/j.coastaleng.2019.103511 |
| Language: | English |
| Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | Wave-current interaction, Bottom boundary layer, Turbulence, Coherent structures, Particle image velocimetry, Hydrogen bubble visualisation |
| 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 Civil, Environ and Geomatic Eng |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10075064 |
Loading...
Loading...Loading...Loading...Archive Staff Only
 |
View Item |
