SPH Modeling of Mean Velocity Circulation in a Rip Current System

Abstract

A Lagrangian numerical model called Smoothed ParticleHydrodynamics is used to analyze rip current system generated by a single bar and a rip channel. The pattern of the wave-induced circulation cell over the bar, the oppositely-rotating circulation cell on-shore and a strong seaward-directed current in the rip channel is modeled numerically. The mean horizontal variations of rip current system as well as three-dimensional circulations are studied. The results in three-dimensional space reveal the wave-current interaction and flow patterns in different parts of rip channel, bar, and the trough located near shore. For comparison to experimental data, Eulerian nodes are introduced to the numerical model and SPH interpolation over neighboring Lagrangian particles is implemented to find fluid parameters at those specific nodes. This methodology leads to a better understanding of depth-integrated flows and a more accurate comparison of numerical results with experimental results. Model predictions are compared to laboratory measurements of Drønen et al. (2002) and show good agreement, including mean velocity profiles, mean surface elevation and three-dimensional velocity components.

Modeling Water Waves with Smoothed Particle Hydrodynamics

“…One of these tests was a comparison to the wave tank experiment of Drønen et al (2002); see Jalali Farahani et al (2012. This experiment was designed to show the generation of a rip current excised into an offshore sand bar, similar to Haller et al (2002).…”