Flow pattern and hydrodynamic parameters of pile breakwater under solitary wave using OpenFOAM

Abstract

Pile breakwaters are widely used for coastal protection. To ensure the safety and hence serviceability of pile breakwaters under disastrous waves like tsunamis, an accurate estimation of wave actions exerted on them is necessary. This work investigates the hydrodynamic properties of solitary waves (resemble tsunami waves) interacting with a single-row pile breakwater using OpenFOAM. Large eddy simulation (LES) is utilized to deal with the turbulent flow, and the free-surface is reproduced by a scheme named THINC/QQ (tangent of hyperbola for interface capturing with quadratic surface representation and Gaussian quadrature). This numerical model is validated against published experimental data. Using the verified model, flow patterns near the piles are interpreted. A parametric study is then conducted on the influences of incident wave height, blockage ratio and pile diameter to the hydrodynamic parameters of pile breakwater, which include wave run-up, wave force and jet velocity. Finally, semi-empirical formulas are established for quick and reliable evaluation of these parameters. The research work can provide guideline for practical design of pile breakwater.