Spatial and temporal distributions of turbulence under bichromatic breaking waves
View/ Open
23837517.pdf (1,726Mb) (Restricted access)
Request copy
Què és aquest botó?
Aquest botó permet demanar una còpia d'un document restringit a l'autor. Es mostra quan:
- Disposem del correu electrònic de l'autor
- El document té una mida inferior a 20 Mb
- Es tracta d'un document d'accés restringit per decisió de l'autor o d'un document d'accés restringit per política de l'editorial que té aplicat un embargament superior a 6 mesos i està vinculat a un projecte finançat per la Comissió Europea
Document typeArticle
Date issued2019-04
Rights accessRestricted access - publisher's policy
(embargoed until 2021-01-30)
European Commisision's project
HYDRALAB-PLUS - HYDRALAB+ Adapting to climate change (EC-H2020-654110)Abstract
The present study aims to extend insights of surf zone turbulence dynamics to wave groups. In a large-scale wave flume, bichromatic wave groups were produced with 31.5 s group period, 4.2 s mean wave period, and a 0.58 m maximum wave height near the paddle. This condition resulted in plunging-type wave breaking over a fixed, gravel-bed, barred profile. Optic, acoustic and electromagnetic instruments were used to measure the flow and the spatial and temporal distributions of turbulent kinetic energy (TKE). The measurements showed that turbulence in the shoaling region is primarily bed-generated and decays almost fully within one wave cycle, leading to TKE variations at the short wave frequency. The wave breaking-generated turbulence, in contrast, decays over multiple wave cycles, leading to a gradual increase and decay of TKE during a wave group cycle. In the wave breaking region, TKE dynamics are driven by the production and subsequent downward transport of turbulence under the successive breaking waves in the group. Consequently, the maximum near-bed TKE in the breaking region can lag the highest breaking wave by up to 2.5 wave cycles. The net cross-shore transport of TKE is in the shoaling region primarily driven by short-wave velocities and is shoreward-directed; in the wave breaking region, the TKE transport is seaward-directed by the undertow and the long-wave velocities. Downward transport of TKE is driven by the vertical component of the time-averaged flow. The cross-shore and vertical diffusive transport rates are small relative to the advective transport rates.
CitationVan der Zanden, J. [et al.]. Spatial and temporal distributions of turbulence under bichromatic breaking waves. "Coastal engineering", Abril 2019, vol. 146, p. 65-80.
ISSN0378-3839
Publisher versionhttps://www.sciencedirect.com/science/article/pii/S0378383918300735
Collections
Files | Description | Size | Format | View |
---|---|---|---|---|
23837517.pdf![]() | 1,726Mb | Restricted access |
Except where otherwise noted, content on this work is licensed under a Creative Commons license:
Attribution-NonCommercial-NoDerivs 3.0 Spain