Shoreline response to detached breakwaters and tidal current : comparison of mumerical and physical models

Shoreline response behind a detached breakwater and at a T-head groin observed in a large-scale physical model was validated with an updated GENESIS model. A new total load longshore sediment transport rate formula, introduced in this paper, was developed and incorporated in GENESIS to address engineering predictive requirements at coastal inlets. The relationship represents the contribution from obliquely incident breaking waves, their gradient alongshore, and external non-wave induced currents, such as the longshore components of a tidal current or wind-induced current. The principle of superposition of current components in the transport relationship is validated against transport rate measurements from physical model tests at the Large-Scale Sediment Transport Facility of the US Army Engineer Research and Development Center

Numerical Simulation of the Shoreline Modifications behind a T-Head Groin

In this paper, the shoreline and bottom modifications produced by the presence of a T-head groin are simulated. We present a model for the bottom-change simulation, composed by two sub-models: a two-dimensional phase-resolving model for the simulation of the variation of the fluid dynamic variables inside the wave period and that takes into account the undertow; a second morphodynamic sub-model for the simulation of the bottom changes, in which the suspended sediment concentration is calculated by means of the wave-averaged advection-diffusion equation. Both the fluid motion equation and the concentration equation are written in a new contravariant formulation. We simulate the velocity fields from deep water to the start of the surf-zone by a new integral contravariant form of the Fully Nonlinear Boussinesq Equations. We simulate the bed evolution dynamics by means of the contravariant formulation of the advection-diffusion equation for the suspended sediment concentration. A quasi three-dimensional approach is used to formulate the advective sediment transport terms in the advection-diffusion equation