EFFECT OF SURFACE ROLLERS ON THE FORMATION OF CRESCENTIC BARS

Daniel Calvete, Francesca Ribas, Huib E. de Swart, Albert Falques

Abstract


The formation of crescentic bars is examined using a morphodynamic model based in linear stability analysis. The effect of surface rollers for off-normal wave conditions is examined. The effect of the rollers is to increase the efolding times with increasing the angle of incidence. For angles large enough the formation of crescentic bars is even inhibit. The main effect of the rollers it be through hydrodynamics. The longitudinal changes in current produced by the rollers cause the maximum of sediment concentration to be shifted towards the coast with the final effect of prevent the formation of crecscentic bars.

Keywords


crescentic bars; rip chanels; surface rollers; morphodynamics; surfzone

References


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