High rayleigh number convection in rotating melt during alloy solidification

This paper reviews high Rayleigh number compositional convection in the melt and in cylindrical chimneys within a mushy layer during alloy solidification and under external constraint of rotation. These chimneys produce freckles in the final form of the solidified material, which are imperfections that reduce the quality of the solidified materials. External constraint of rotation imposed on the solidification system is used to predict particular ranges of the parameter values under which undesirable chimney convection can be suppressed or reduced as much as possible leading to elimination or reduction of the effects of chimneys as much as possible . Asymptotic and scaling analyses can be applied effectively to both axisymmetric and non-axisymmetric convection in the melt and in the chimneys to determine the effects of the centrifugal and Coriolis forces on the motion of the melt. The flow system is reviewed here for high or moderate values of the Prandtl number, and new results are also reported in this paper for such parameter regime