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Mechanism of finite-amplitude double-component convection due to different boundary conditions

N. Tsitverblit
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Abstract

A new mechanism of double-component convection is discovered. It emerges in a horizontal layer of Boussinesq fluid as a stable stratification due to flux boundary conditions is added to an unstable gradient specified by fixed boundary values. A large enough perturbation substantially decreases the stable flux gradient but fails to mix the unstable fixed-value gradient. Steady finite-amplitude flows reminiscent of Rayleigh--Benard convection then arise even as the net background stratification is stable, emphasizing the importance of the identified mechanism for double-component fluid systems. V2 Abstract: A new mechanism of double-component convection is discovered. It emerges in a horizontal layer of Boussinesq fluid as a stable stratification due to flux boundary conditions is added to an unstable gradient specified by fixed boundary values. Driven by this mechanism, steady finite-amplitude flows reminiscent of Rayleigh--Benard convection arise even when the background density stratification is stable.

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N. Tsitverblit. 2004-08-31. Mechanism of finite-amplitude double-component convection due to different boundary conditions. https://doi.org/10.1016/j.physleta.2004.07.011

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