三维枝晶生长的相场法数值模拟研究

基于薄界面限制、耦合界面能各向异性的相场模型，采用动态计算区域的加速算法，对纯物质的三维枝晶生长进行了定量模拟，真实再现了枝晶的生长过程.对枝晶尖端进行了剖切分析，表明主枝截面上各向异性没有主枝方向各向异性明显；对枝晶尖端生长速度、尖端半径、Peclet数及临界稳定性参数σ^*进行模拟计算，并与同条件下报道值进行了对比分析，两者符合良好，并得到了与结晶理论相一致的枝晶生长规律，证实了相场方法模拟三维空间枝晶生长可行有效. 关键词： 相场方法 枝晶生长 微观组织 三维数值模拟

Numerical simulation of three-dimensional dendritic growth using phase-field method

Quantitative numerical simulation of three-dimensional dendritic growth in pure undercooled melt is carried out based on phase-field model of thin-interface limit and incorporating interfaciul energy anisotropy which is solved by an accelerated algorithm of the dynamic computing regions, the dendritic growth is faithfully described. The dendritic tip is analyzed by cutaway view, indicating that the anisotropy of main branches' section is not more obvious than that of main branches. The dendritic tip growth speed, tip radius, tip Peelet number as well as classic stability parameter σ~* are simulated, compared with reported values under same condition, and they agree well with each other. Dendritic growth law that is in accordance with crystalline theroy is achieved, and it is proved that it is feasible and effective to simulate three-dimensional dendritic growth using phase-field method.