Computation of microsegregation and microstructure in solidification with fluid convection

摘要

The effects of fluid flow on the dendritic solidification morphology of pure materials is studied using a computational methodology based on a two-dimensional front tracing/finite difference method. A general single-field formulation is presented for the full copuling of phase change, fluid flow, and heat transport in both the solid and liquid phases. This formulation accounts for interfacial rejection/absorphtion of latent heat, interfacial anisotropies, discontinuities in material properties between the liquid and solid phases, shrinkage/expansion upon solidification and moton and deformation of the solid. Numerical results are presented for the dendritic solidification of pure succinonitrile in a shear flow. Comparison with solidification into a quiescent liquid indicates that fluid convection increases the overall rate of solidification while the growth rate of the leading dendrite tip is unchanged.