Effect of Plateau Length on the Transformation of Internal Solitary Waves

Abstract

The propagation and dissipation of internal waves over continental shelf bathymetry are complex phenomenon. The waveform would be re-generated while transmitting a submerged deep-shallow-deep topography. To study the effect of the marine topography on the evolution of an internal wave, numerical simulation is utilized to perform the flow evolution and waveform inversion of a large depression internal wave over a trapezoidal obstacle with different plateau. A finite volume based Cartesian grid method is adopted to solve the Reynolds averaged Navier-Stokes equations using a k-ε model for the turbulence closure. Numerical results reveal that the re-generated waveform does not occur due to baroclinic wave. The shorter plateau length would induce strong vortex in back of the obstacle. Moreover, the wave amplitude, vorticity and turbulent kinetic energy are dissipated significantly. However, the level of the phenomenon decreases as the plateau length is larger than the wavelength.