In an experiment with a wavelength of 10.26 feet (wave period = 1.50 seconds) on an initial movable-bed slope of 0.10 in a tank 10 feet wide with waves directed normal to the initial shoreline, the foreshore and inshore changes of the profile were three-dimensional to such an extent that a longshore current developed at the base of the foreshore. Comparable experiments in the same facility, but with a longer wavelength, did not show three-dimensional effects to as great an extent. As a working hypothesis, it is proposed that the shorter the wavelength in a movable-bed experiment relative to a given tank width, the greater the likelihood of three-dimensional effects in profile development. The wave steepness was higher than the wave steepness in the comparable earlier experiments (0.039 versus 0.021 in Vols. II, III, and IV of the series), and the reflection coefficient was lower, as would be expected from increased breaker dissipation of steeper waves and for a shorter wave on the same slope. Variations in the reflection coefficient may have been caused by the change in phase difference between the waves reflected from the offshore slope and the foreshore slope as those two zones moved farther apart on the developing profile. The profile appeared to have almost attained an equilibrium shape after 150 hours, in contrast to the comparable experiments with lower wave steepness, which were not approaching equilibrium after a much longer time in the same facility.


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    Titel :

    Laboratory Effects in Beach Studies, Volume 5: Movable-Bed Experiments with Ho/Lo = 0.039 (1972)


    Beteiligte:

    Erschienen in:

    Erscheinungsdatum :

    1977


    Format / Umfang :

    20240963


    Medientyp :

    Report


    Format :

    Elektronische Ressource


    Sprache :

    Englisch



    Klassifikation :


    Laboratory Effects in Beach Studies, Volume 4: Movable-Bed Experiments with Ho/Lo = 0.021 (1972)

    Chesnutt, Charles B. / Stafford, Robert P. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1977

    Freier Zugriff

    Laboratory Effects in Beach Studies, Volume 6: Movable-Bed Experiments with Ho/Lo = 0.004

    Chesnutt, Charles B. / Stafford, Robert P. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1978

    Freier Zugriff

    Laboratory Effects in Beach Studies, Volume 7: Movable-bed experiments with Ho/Lo = 0.013

    Chesnutt, Charles B. / Stafford, Robert P. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1978

    Freier Zugriff

    Laboratory Effects in Beach Studies, Volume 2: Movable-Bed Experiments with Ho/Lo = 0.021 (1970)

    Chesnutt, Charles B. / Stafford, Robert P. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1977

    Freier Zugriff

    Laboratory Effects in Beach Studies, Volume 1: Procedures Used in 10 Movable-Bed Experiments

    Stafford, Robert P. / Chesnutt, Charles B. | HENRY – Bundesanstalt für Wasserbau (BAW) | 1977

    Freier Zugriff