VARIATION OF WAVE ROLLER SLOPE IN THE SURF ZONE

Chi Zhang, Yali Chen, Jinhai Zheng, Zeki Demirbilek

Abstract


Although the concept of breaking wave roller has been widely used in parametric surf zone modelling, the key physical parameter, wave roller slope, was not well understood and often simply assumed as a time- and space-independent constant. Based on an experimental analysis of breaking wave roller evolution, we found that the actual roller slopes are greater than those commonly used. Moreover, the roller slope is cross-shore variable with a peak at the breaking point. Applying the observed roller slopes into the conventional wave energy and momentum balance equations leads to improved calculated results of roller length evolution and wave setup. This implies the importance of an appropriate parameterization of space-dependent wave roller slope in modelling of surf zone processes.

Keywords


wave breaking; roller; cross-shore variation; surf zone

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References


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DOI: https://doi.org/10.9753/icce.v34.waves.12