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arXiv · 1005.5261

Transient convective instabilities in directional solidification

Esteban Meca·Laureano Ramirez-Piscina
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Abstract

We study the convective instability of the melt during the initial transient in a directional solidification experiment in a vertical configuration. We obtain analytically the dispersion relation, and perform an additional asymptotic expansion for large Rayleigh number that permits a simpler analytical analysis and a better numerical behavior. We find a transient instability, i.e. a regime in which the system destabilizes during the transient whereas the final unperturbed steady state is stable. This could be relevant to growth mode predictions in solidification.

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Esteban Meca, Laureano Ramirez-Piscina. 2010-11-10. Transient convective instabilities in directional solidification. https://doi.org/10.1063/1.3511520

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