THE FLOW OVER ASYMMETRICAL RIPPLES: EXPERIMENTAL INVESTIGATION ON THE MORPHODYNAMIC BEHAVIOR

Carla Faraci, Carmelo Petrotta, Pietro Scandura, Enrico Foti, Paolo Blondeaux

Abstract


This paper reports on an experimental campaign focused on the generation and evolution of small scale bedforms over a sloping sandy beach. The wave propagation over a sloping bed triggers a flow asymmetry that reflects on the bedform characteristics. Morphodynamic analyses on ripple evolution and migration led to observe that at the equilibrium the ripples have larger offshore flanks and are leant toward the beach. However migration velocity may be onshore or offshore directed. The equilibrium ripple characteristics seem to be well described by Nielsen (1981) ripple predictor.

Keywords


ripple evolution; asymmetric waves; migration velocity

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References


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DOI: https://doi.org/10.9753/icce.v35.sediment.35