Radiation Instability in a Stratified Shear Flow
نویسندگان
چکیده
The paper deals with a new mechanism of instability in stratified fluid caused by internal wave radiation from a shear layer. This radiation instability may be explained in terms of the negativeenergy wave concept. These waves are able to grow due to radiation losses. The dispersion relation and non-linear stage of the process are analyzed through a model with tangential velocity discontinuity. The non-linear description is based on a long-wave approximation leading to an evolution equation of the Korteweg-de Vries type with certain additional terms responsible for instability as well as dissipation due to turbulence. Approximate solutions of the equation are obtained which, in particular, describe the evolution of solitons including explosive growth and approaching the steady state.
منابع مشابه
Analytical and Numerical Studies on Stratified Fluid Flows
CLAUDIO VIOTTI: ANALYTICAL AND NUMERICAL STUDIES ON STRATIFIED FLUID FLOWS. (Under the direction of Roberto Camassa and Richard M. McLaughlin.) The mathematical modeling of stratified fluid flows is the overall subject of this work, which spans a range of more specific topics: internal gravity waves, shear instability, anomalous diffusion of passive scalars, vortex rings dynamics in stratified ...
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