Abstract
Nonlinear compositional convection in the melt and in cylindrical chimneys within a mushy layer during solidification of a binary alloy is investigated subjected to a strong magnetic field and under high gravity environment. Asymptotic and scaling analyses are applied to axisymmetric convection in the melt and in the chimneys. Three important nondimensional parameters are the solutal Rayleigh number R, the centrifugal acceleration parameter A, and the Chandrasekhar number (magnetic parameter) Q. Magnetohydrody-namic effects, due to the presence of a strong magnetic field, are stabilizing in the sense that convection and freckle formation can be reduced significantly. Such stabilizing effects can be enhanced by the presence of a moderate rate of rotation due to centrifugal force effects. In this stabilizing regime, chimney convection decreases with increasing either A or Q, even though it still increases with R.
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Riahi, D.N. (2001). Magnetohydrodynamic Effects in High Gravity Convection During Alloy Solidification. In: Regel, L.L., Wilcox, W.R. (eds) Processing by Centrifugation. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-0687-4_39
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DOI: https://doi.org/10.1007/978-1-4615-0687-4_39
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