Turbulence Characteristics of Internal Waves in an Improved 3D Numerical Wave Tank

Abstract

A three-dimensional unsteady mathematical model was applied to simulate the generation and propagation of the internal solitary waves in an improved numerical wave tank. The turbulence characteristics of the internal waves were investigated by means of the turbulence model, a concept of a fractional volume of fluid (VOF) was employed to track the internal interface of two-layer water. The effect of irregular topography on turbulence was described by the spatial and temporal distributions of turbulence kinetic energy, its dissipation rate. Simulation results show that the highest values of turbulence kinetic energy and its dissipation rate occur at the interface of two-layer water when waves propagate in both flat and irregular terrains. The values are higher in irregular topography cases than those in flat topography cases, which indicates that the turbulence associated with abrupt topographies is more intensive. The paper provides a reasonable approach for understanding the turbulence characteristics of internal waves in density-stratified waters.