用相场方法模拟纯物质在过冷状态下的二维枝晶生长

Simulation of 2-D Dendritic Growth of Pure Material in Supercooled State Using Phase Field Method

通过相场理论建立了纯物质镍在过冷溶液中枝晶生长的相场模型.把相场方程和温度场方程进行耦合,建立了相对应的相场模型.该模型以熵增加函数为基础,通过熵增加函数推导出热力学一致性的相场控制方程.利用上述的模型和方法在计算机上编制二维组织凝固模拟程序得出结论:网格精度影响模拟过程的精确度;各向异性强度影响枝晶尖端生长速度.

In this dissertation we set up a model of dendrtic growth for pure material Ni in supercooled liquid. This model coupled the equations of the phase field and the temperature field. Based on entropy increase function, we has derived the phase field controlling equations which are thermodynamical consistent. With the above model and method, we draw up the program of the 2-D solidification microstructure. We draw the conclusion： The anisotropy intensity influence growth speed of dendritic peak, and reseau precision influence the precision of numerical simulation.