Author(s): Abbas Khayyer; Abbas Yeganeh-Bakhtiary; Abbas Ghaheri; Hitoshi Gotoh; Tetsuo Sakai
Linked Author(s): Hitoshi Gotoh
Keywords: Turbulence dynamics; Breaking waves; Surf zone; Turbulence characteristics; Plunging breaking waves; Surging breaking waves
Abstract: Dynamics of surf zone turbulence in plunging and surging breaking waves have been investigated by means of a two-dimensional numerical model. A two-dimensional RANS solver, a VOF (Volume Of Fluid) free surface model and a k-ε turbulence closure model have been combined to numerically simulate solitary plunging and surging breaking waves and to investigate turbulence dynamics in such breakers. Spatial distributions of turbulence characteristics, i. e., turbulence kinetic energy, k, turbulence dissipation rate, ε, turbulence production, rp, and turbulence eddy viscosity, tν, have been discussed in detail. Turbulent intensities in breaking waves appear to be highest near the free surface and under the wave crest. The results obtained from this study confirm the hypothesis that most of the turbulence in inner surf zone is produced in the “surface roller” region. The main characteristic of plunging breaking waves, shoreward advective transport of turbulence, has been also numerically examined. Turbulence transport in surging breaking waves also seems to be dominated by advection either.
Year: 2005