Observation of the coherent turbulent structure under breaking wave

Zhi Cheng Huang, Shih Chun Hsiao, Hwung Hweng Hwung

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Previous studies qualitatively sketched that relative larger coherent turbulent motions generated in the crest region would stretch downward into the trough level during propagation of breaking wave in the surf zone. This event further suggests that an instantaneous burst of turbulence intensity will occur locally in the path of the penetrating turbulent motion. To observe such a spatial depended turbulent structure, the internal flow field of spilling wave propagating on an inclined bottom slope of 1/20 was measured quantitatively by Particle Image Velocimetry. The ensemble average method is employed to decompose the mean flow and turbulent fluctuations by repeating the same experiment for twenty-five times in each Field of View (FOV). Seven FOVs were integrated for representing the global results, which covers the breaking wave from the outer to inner surf zones. The temporal and spatial evolutions of the coherent turbulent structure were examined and discussed. Results manifest that a relative large turbulent motion is initially organized in the wave crest of the bore-established region. As the wave crest passed, this turbulent structure will then stretch downward to the interior region of the water column. Two important dynamic turbulence transport terms, the turbulent convection and diffusion, were estimated to investigate the underline mechanism of the turbulence transport. It is found that the convection term is much significant to spread the turbulent structure from the wave crest to trough region.

Original languageEnglish
Title of host publicationProceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008
Pages256-263
Number of pages8
Publication statusPublished - 2008 Dec 1
Event18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008 - Vancouver, BC, Canada
Duration: 2008 Jul 62008 Jul 11

Publication series

NameProceedings of the International Offshore and Polar Engineering Conference
ISSN (Print)1098-6189
ISSN (Electronic)1555-1792

Other

Other18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008
CountryCanada
CityVancouver, BC
Period08-07-0608-07-11

Fingerprint

Turbulence
Velocity measurement
Flow fields
Water
Experiments
Convection

All Science Journal Classification (ASJC) codes

  • Energy Engineering and Power Technology
  • Ocean Engineering
  • Mechanical Engineering

Cite this

Huang, Z. C., Hsiao, S. C., & Hwung, H. H. (2008). Observation of the coherent turbulent structure under breaking wave. In Proceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008 (pp. 256-263). (Proceedings of the International Offshore and Polar Engineering Conference).
Huang, Zhi Cheng ; Hsiao, Shih Chun ; Hwung, Hwung Hweng. / Observation of the coherent turbulent structure under breaking wave. Proceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008. 2008. pp. 256-263 (Proceedings of the International Offshore and Polar Engineering Conference).
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Huang, ZC, Hsiao, SC & Hwung, HH 2008, Observation of the coherent turbulent structure under breaking wave. in Proceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008. Proceedings of the International Offshore and Polar Engineering Conference, pp. 256-263, 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008, Vancouver, BC, Canada, 08-07-06.

Observation of the coherent turbulent structure under breaking wave. / Huang, Zhi Cheng; Hsiao, Shih Chun; Hwung, Hwung Hweng.

Proceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008. 2008. p. 256-263 (Proceedings of the International Offshore and Polar Engineering Conference).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Huang ZC, Hsiao SC, Hwung HH. Observation of the coherent turbulent structure under breaking wave. In Proceedings of the 18th 2008 International Offshore and Polar Engineering Conference, ISOPE 2008. 2008. p. 256-263. (Proceedings of the International Offshore and Polar Engineering Conference).