The phase field method is employed to investigate the interactions between melt flow and dendritic growth in two dimensions. The phase field formulation is based on a recent asymptotic analysis carried out by Karma and Rappel (1995, 1996), which relaxes the computational constraints imposed by the interface thickness and substantially improves computational efficiency. The flow field is simulated numerically by solving continuity and Navier-Stokes equations using the formulation of Diepers et al. (1997). Results are presented for hte evolution of a freely growing dendrite under the influence of melt flow. Dendrite tip velocities and radii are exaamined in order to quantify the effect of convection. It is found that the orientation of the dendrite with respect to the flow is a very important factor when the convection velocity is comparable to the tip growth velocity. The tip selection criterion in the presence of melt convection is also discussed.
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