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Register a new userPreventing transition to turbulence: a viscosity stratification does not always help
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Added by
Vijayakumar Chikkadi
Publication date
2005
fields
Physics
and research's language is
English
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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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