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Preventing transition to turbulence: a viscosity stratification does not always help

Vijayakumar Chikkadi·A. Sameen·Rama Govindarajan
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Abstract

In channel flows a step on the route to turbulence is the formation of streaks, often due to algebraic growth of disturbances. While a variation of viscosity in the gradient direction often plays a large role in laminar-turbulent transition in shear flows, we show that it has, surprisingly, little effect on the algebraic growth. Non-uniform viscosity therefore may not always work as a flow-control strategy for maintaining the flow as laminar.

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Vijayakumar Chikkadi, A. Sameen, Rama Govindarajan. 2005-11-11. Preventing transition to turbulence: a viscosity stratification does not always help. https://doi.org/10.1103/physrevlett.95.264504

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