# Parametric subharmonic instability of internal waves: locally confined beams versus monochromatic wavetrains

@article{Karimi2014ParametricSI,
title={Parametric subharmonic instability of internal waves: locally confined beams versus monochromatic wavetrains},
author={Hussain H. Karimi and T. R. Akylas},
journal={Journal of Fluid Mechanics},
year={2014},
volume={757},
pages={381 - 402}
}
• Published 17 September 2014
• Physics
• Journal of Fluid Mechanics
Abstract Internal gravity wavetrains in continuously stratified fluids are generally unstable as a result of resonant triad interactions which, in the inviscid limit, amplify short-scale perturbations with frequency equal to one half of that of the underlying wave. This so-called parametric subharmonic instability (PSI) has been studied extensively for spatially and temporally monochromatic waves. Here, an asymptotic analysis of PSI for time-harmonic plane waves with locally confined spatial…
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