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http://dx.doi.org/10.9713/kcer.2012.50.1.061

Linear Stability of Compositional Convection in a Mushy Layer during Solidification of Ammonium Chloride Solution  

Hwang, In Gook (Department of Chemical Engineering, The University of Suwon)
Publication Information
Korean Chemical Engineering Research / v.50, no.1, 2012 , pp. 61-65 More about this Journal
Abstract
The onset of convection in a mushy layer is analyzed by using linear stability theory in time-dependent solidification of a binary melt. A simplified model of a near-eutectic mush, in which the mush is assumed to be a porous block, is used and the propagation theory is applied to determine the critical conditions for the onset of convection. The present critical Rayleigh number is higher than the existing experimental result and also theoretical results obtained by considering the mushy layer with an overlying liquid layer. The constant pressure (permeable) condition applied on the mush-liquid interface produces a lower critical Rayleigh number, which is closer to the experimental results of aqueous ammonium chloride solution, compared with the impermeable condition.
Keywords
Mushy Layer; Compositional Convection; Solidification; Linear Stability; Propagation Theory;
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