Numerical Simulation of Breaking Waves in Front of Seawalls Using Projection Method

Document Type : Original Article

Authors

1 Ph. D. in Hydraulics, Tarbiyat Modarres University, Tehran, Iran

2 Assistant Professor, Tarbiyat Modarres University, Tehran, Iran

3 Assistant Professor, Tehran University, Tehran, Iran

4 Sharif University of Technology, Tehran, Iran

Abstract

The complicated structure of the surf zone with a strong unsteadiness has prevented us to fully understand its internal structure. Numerical models are one of the best tools to study hydrodynamic phenomena in this zone. In this paper, a two-dimensional vertical (2DV) model is proposed to study breaking waves in front of seawalls. The numerical model consists of an unsteady hydrodynamic module in which the fully Navier-Stokes equations in vertical plain are solved using the projection method. Finite volume method is employed to discrete convection and diffusion terms of governing equations with Froum and Crank Nicolson methods, respectively. The free surface water is tracked by using the Young technique. Using standard  model to simulate turbulence effects showed reasonable results. Finally, the numerical results are compared with wave flume measurements for the same conditions. The result of the proposed model shows close agreement with experimental measurements in terms of surface elevations, horizontal and vertical velocity and flow pattern in front of the seawall.

 

Keywords


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