Effect of Breaking Waves and External Current on Longshore Sediment Transport

Abstract

The effects of external currents on the longshore current and sediment transport in the surf zone are examined using the cross-shore numerical model CSHORE, which is extended to include the alongshore pressure gradient term in the longshore momentum equation and to allow oblique waves in the swash zone on a beach. The extended CSHORE is compared with five tests conducted in a wave basin with a recirculation system. The cross-shore variations of the longshore current and sediment-transport rate are predicted fairly well for the cases of no and favorable pressure gradients. The cases of adverse and time-varying pressure gradients are computed to extrapolate the experimental results for wider applications.