A One-Dimensional Parametric Model for Undertow and Longshore Current Velocities on Barred Beaches

Abstract

A one-dimensional parametric model for undertow and longshore current velocities assuming a triangular velocity distribution in a surface roller was developed. This model as well as a parametric model with the assumption of a uniform velocity distribution in a roller was compared with field data obtained on barred beaches at Hasaki in Japan and at Duck in the USA. The comparisons showed that the present model predicted the velocity fields at the two sites reasonably well, and the prediction accuracy of the present model is slightly better than that of the other model. However, the present model underpredicted the undertow velocities on the trough regions, and overestimated the longshore current velocities near the shorelines.

Countermeasure Against Erosion Behind Submerged Breakwater Due to Sea Level Rise

“…As the input offshore wave heights and periods, the values measured from 2001 to 2011 were repeatedly used. The offshore wave heights considering the wave energy dissipation over the submerged breakwater were estimated using the model developed by Kuriyama (2010), which estimates the cross-shore variation of root-meansquare wave height assuming that the wave height probability density function has a Rayleigh distribution. The estimated significant wave heights 150 m shoreward of the submerged breakwater (z = −8.8 m) were transformed to the offshore values using the shoaling coefficients.…”

Numerical Study of Sandbar Migration under Wave-Undertow Interaction

“…where k s 5 bed roughness, taken as 2:5d 50 in which d 50 is the median grain size of sediment. The present flow module describes the phase-and depth-resolving flow motion that takes into account the nonlinear waves, undertow, and bottom boundary-layer streaming, the three important processes essential for modeling cross-shore sediment transport and beach profile evolution (e.g., Gallagher et al 1998;Hoefel and Elgar 2003;Hendersen et al 2004;Kuriyama 2010). The simulated intrawave bed shear stress and flow velocity are used to drive the sediment-transport module.…”