Finite-Amplitude Disturbances and Near-Threshold Instability of Hydrodynamic Flows
We consider theoretical models of possible initial stages of development, due to finite-amplitude wave instability,of turbulent spots in stratified shear flows when wave and flow parameters are near the stability threshold. It is shown that, in contrast to analogous processes in plasma, nonlinear frequency shift does not provide saturation of explosive resonant interaction of the marginal waves. A condition of instability due to redistribution of energy, by wave-induced turbulence, from the flow to wave is found and estimates of the growth rate are obtained analytically.
KeywordsConvection Explosive Stratification Expense Cond
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