Numerical Simulation of Dendritic Growth into Undercooled Melt Using Phase-Field Method

Based on a phase-field model,a series of numerical calculations of dendritic growth into undercooled melt for a pure material were performed,and the influence of some physical parameters,including anisotropy strength,undercooling and noise factor,on dendritic growth were investigated.Results showed that the noise could trigger the growth of side-branches,but this did not influence the selection of the tip operating state.The greater the anisotropy strength,the faster the tip velocity and the more obvious the characteristics of the dendritic structure.With the increase in undercooling,the stability of the tip operating state was gradually upset,and if seriously,branching-off of the dendrite tip could be seen.Finally,effect of mesh size on simulation result was discussed,and it was pointed out that the coarser mesh should be selected preferably when the resolution and time of computation is considered simultaneously.