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Mathematical and physical modelling of doublediffusive convection of aqueous solutions crystallizing at a vertical wall

Published online by Cambridge University Press:  21 April 2006

Mollie E. Thompson
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
Julian Szekely
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA

Abstract

Solidification of a double-diffusive liquid from a vertical wall in a rectangular cavity is investigated using both mathematical and physical modelling. A two-dimensional mathematical model is developed to simulate the process of solidification in a two-component liquid containing a denser solute. Observations on the solidification behaviour of aqueous sodium carbonate solutions are used to verify the results of the mathematical analysis. The theory and experiments provide a clear picture of the role of double-diffusion in producing vertical compositional and density stratification in an initially homogeneous liquid during solidification. The development of horizontally oriented convection cells in the stratified liquid is correlated with the magnitude of the destabilizing lateral temperature difference across the liquid region.

Type
Research Article
Copyright
© 1988 Cambridge University Press

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