Numerical Modelling of Wave Fields and Currents in Coastal Area

Francesco Gallerano

doi:10.3390/w12061582

Abstract

The design and management of coastal engineering, like harbors and coastal defense structures, requires the simulation of hydrodynamic phenomena. This special issue collects five original papers that address state of the art numerical simulations of wave fields and wave-induced velocity fields in coastal areas. The first paper proposes a turbulence model for wave breaking simulation, which is expressed in terms of turbulent kinetic energy and dissipation rate of turbulent kinetic energy (k − ε); the proposed turbulence model is a modification of the standard k − ε turbulence models. The second paper investigates modalities by which wind interacts with wave motion, modifying the wave propagation dynamic. The third paper proposes a study on waves overtopping over coastal barriers. The fourth paper details the numerical simulation of a tsunami wave that propagates over an artificial reservoir, caused by a landslide that creates a solid mass to detach from the slopes and to slide into the reservoir. The fifth paper examines an application case concerning Cetraro harbor (Italy), which is carried out using three-dimensional numerical simulations of wave motion.

Highlights

The simulation of wave fields and wave-induced velocity fields is necessary to evaluate the actions exerted by the sea on coastal structures, as well as to forecast the effects produced by these structures on the morphological evolution of shorelines
The topics of this special issue range from new numerical schemes for wave propagation simulation; evolutions from deep water to shoreline; numerical investigations regarding specific problems like wave-breaking, turbulence models, wind effects on wave propagation over a sloping bed, wave overtopping, and dynamics related to wet-dry front propagation
This special issue concerns the simulation of wave fields and wave-induced velocity fields in coastal areas

Summary

Introduction

The simulation of wave fields and wave-induced velocity fields is necessary to evaluate the actions exerted by the sea on coastal structures, as well as to forecast the effects produced by these structures on the morphological evolution of shorelines. In models based on BEs, the dispersive terms are switched off at the beginning of the breaking zone, which reduce BEs to NSWE These models are able to simulate wave breaking thanks to the use of shock-capturing schemes. A numerical procedure (for the three-dimensional simulation of the wave motion) alternative to VOF methodology is defined in the context of shock-capturing schemes, in which the vertical coordinate varies in time to follow free surface movements. When motion equations are expressed in terms of conserved variables, the high-order shock captures numerical schemes that guarantee convergence to a correct weak solution and are able to track the actual location of the breaking wave without requiring any criterion. The motion equations are expressed in terms of Cartesian-based unknown variables on a time-dependent generalized curvilinear coordinate system; in the second case, the motion equations are expressed in a contravariant formulation and solved on a time-dependent generalized curvilinear coordinate system

Overview of the Special Issue

Conclusions