Numerical simulation of mass transport in internal solitary waves

Maher Salloum, Omar Knio*, Alan Brandt

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

A computational study of mass transport by large-amplitude, mode-2 internal solitary waves propagating on a pycnocline between two layers of different densities was conducted. The numerical model is based on the simulation of a vorticity-based formulation of the two-dimensional Navier-Stokes equations in the Boussinesq limit. Numerical experiments are conducted of the collapse of an initially mixed region, which leads to the generation of a train of internal solitary waves. The peak wave amplitude, a, is achieved by the leading wave, which encloses an intrusional bulge. The wave amplitude decays as it moves away from the collapsing mixing region. When the amplitude drops below a critical value, the wave is no longer able to transport mass and sharp-nosed intrusion is left behind. Mass transport by the leading waveby the trailing wave train and intrusion, is analyzed by tracking the motion of Lagrangian particles initially concentrated in the mixed region. Results indicate that for moderate wave amplitudes, a gradual decay in the wave amplitude occurs as the wave propagates, but the structure of the bulge is essentially maintained during this process. In contrast, for large-amplitude waves, the motion around the bulge is substantially more complex, exhibiting periodic shedding of vortex structures in the wake of the bulge and entrainment of external fluid into its core. It is shown that these motions have substantial impact on mass transport by the wave train, which is quantified through detailed analysis of the Lagrangian particle distributions.

Original languageEnglish (US)
Article number016602
JournalPhysics of Fluids
Volume24
Issue number1
DOIs
StatePublished - Jan 5 2012

ASJC Scopus subject areas

  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Numerical simulation of mass transport in internal solitary waves'. Together they form a unique fingerprint.

Cite this