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arXiv · 1204.5024

Large-scale instability in hydrodynamics with stable temperature stratification driven by small-scale helical force

Anatoly V. Tur·Vladimir V. Yanovsky
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Abstract

In this work we consider the effect of a small-scale helical driving force on fluid with a stable temperature gradient with Reynolds number Re<<1. At first glance, this system does not appear to have any instability. However, we show that large-scale vortex instability appears in fluid despite its stable stratification. In the non-linear mode, this instability gets saturated and gives a large number of stationary spiral vortex structures. Among these structures there is a stationary helical soliton and a kink of a new type. The theory is built on the rigorous asymptotical method of multi-scale development.

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Anatoly V. Tur, Vladimir V. Yanovsky. 2012-04-23. Large-scale instability in hydrodynamics with stable temperature stratification driven by small-scale helical force. https://arxiv.org/abs/1204.5024

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