A THREE-DIMENSIONAL LATTICE BOLTZMANN-CELLULAR AUTOMATON MODEL FOR DENDRITIC SOLIDIFICATION UNDER CONVECTION

摘要

A three-dimensional(3D)lattice Boltzmann(LB)-cellular automaton(CA)model is developed for dendritic solidification of a binary alloy under the effect of melt convection. The model employs LB method to solve for solute transport and fluid dynamics around growing dendrites. CA is adopted to capture solid/liquid interface. It is shown that convection can alter the growth kinetics by affecting solute distribution around the dendrites. The evolution of Al-Cu dendritic morphologies under forced melt convection is discussed. In addition, the effect of undercooling, inlet flow velocity, and alloy composition on the dendrite's tip velocities is studied.