摘要
采用相场方法对金属枝晶的生长过程进行数值模拟。用凝固相场方程描述过冷条件下枝晶生长的物理过程,同时在相场方程中耦合温度场方程以体现凝固过程中释放的潜热对相变的影响。采用有限差分法进行求解,讨论了松弛时间、方向角、界面宽度、熔点、各向异性、潜热等因素对枝晶的形状和生长的影响。结果表明,随着松弛时间、界面宽度和熔点的逐渐增加,晶体的生长速率也在逐渐增加,并且枝晶越来越发达。
The growth of metal dendritic crystal is simulated numerically by using phase field method. The phase-field equation of solidification is used to describe the physical process of dendritic growth under the condition of un-dercooling. Meanwhile,the temperature evolution equation is coupled into phase-field equation to reflect the influ-ence of the latent heat released during the process of solidification on phase change. The finite difference method is used to solve the phase-field and temperature equations. The evolution and shapes of dendrites under different con-ditions are given. The influences of the parameters,such as relaxation time,orientation angle,interfacial width,melt-ing temperature,interface anisotropy and latent heat,on the growth and shape of dendrite,are discussed in detail. Numerical results show that the growth rate of crystal increases gradually,and the dendrites will be fully developed as the values of relaxation time,the interface width and the melting point increase.
出处
《太原科技大学学报》
2015年第2期160-164,共5页
Journal of Taiyuan University of Science and Technology
基金
山西省自然科学基金(2012011019-2)
太原科技大学博士基金(20112011)
关键词
枝晶生长
相场模型
有限差分法
dendritic growth
phase-field method
finite difference method
