Numerical study on evolution of an internal solitary wave across an idealized shelf with different front slopes

⿢Numerical simulations are performed to investigate the flow evolution of an internal solitary wave of depression over an idealized shelf with different front slopes.⿢A finite volume method is used to solve the Reynolds averaged Navier-Stokes equations using a k-ε model for the turbulent closure.⿢Physical components in the turbulent energy budget throughout wave evolution are differentiated during the wave-obstacle interaction.⿢Effect of three physical parameters that influence wave evolution is examined, which are front slope, depth ratio and incident wave amplitude. Numerical simulations are performed to investigate the influence of variable front slopes on flow evolution and waveform inversion of a depression ISW (internal solitary wave) over an idealized shelf with variable front slopes. A finite volume based on Cartesian grid method is adopted to solve the Reynolds averaged Navier-Stokes equations using a k-ε model for the turbulent closure. Numerical results exhibit the variations of several pertinent properties of the flow field, in the case with or without waveform inversion on the horizontal plateau of an obstacle. The clockwise vortex is stronger than the counterclockwise one, almost throughout the wave-obstacle interaction. Analysis of the turbulent energy budget reveals that the turbulent production term in the governing equations dominates the wave evolution during a wave-obstacle interaction; otherwise the buoyancy production term and the dissipation term due to viscosity within turbulent eddies play a major role in energy dissipation. In addition, the front slope affects mainly the process and reflection of the wave evolution but has less influence than other physical parameters. Moreover, total wave energy of the leading crest is smaller than that of the leading trough even in the cases with waveform inversion on the plateau.