Vortex train in an offshore zone

Nobuhiro Matsunaga, Kosei Takehara

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

    Abstract

    A row of vortices forms in an offshore zone when two-dimensional regular surface waves run up on a sloping flat bed. It is called the offshore vortex train. The vortices begin to appear near a breaking point. Moving in the offshore direction, they develop and increase their horizontal length scale through the vortex merging. The vortex train forms due to the shear instability between onshore and offshore drift-currents. After reaching a location of the offshore side, however, they decay rapidly because of the decrease of shear strain rate between the drift-currents. The formation region has been investigated on the basis of visual experiments for three bed sloped. The formation does not depend on the type of wave breaking but is observes when the steepness of deep water waves is smaller than 4.2 × 102. The horizontal length scale of the vortices and the velocity of the vortex movement have also been evaluated empirically

    Original languageEnglish
    Title of host publicationProceedings of the Coastal Engineering Conference
    Editors Anon
    PublisherPubl by ASCE
    Pages3163-3177
    Number of pages15
    ISBN (Print)0872629333
    Publication statusPublished - Jan 1 1993
    EventProceedings of the 23rd International Conference on Coastal Engineering - Venice, Italy
    Duration: Oct 4 1992Oct 9 1992

    Publication series

    NameProceedings of the Coastal Engineering Conference
    Volume3
    ISSN (Print)0893-8717

    Other

    OtherProceedings of the 23rd International Conference on Coastal Engineering
    CityVenice, Italy
    Period10/4/9210/9/92

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    All Science Journal Classification (ASJC) codes

    • Ocean Engineering

    Cite this

    Matsunaga, N., & Takehara, K. (1993). Vortex train in an offshore zone. In Anon (Ed.), Proceedings of the Coastal Engineering Conference (pp. 3163-3177). (Proceedings of the Coastal Engineering Conference; Vol. 3). Publ by ASCE.