| Title | A cellular automaton technique for modelling of a binary dendritic growth with convection |
| Authors | Li, Daming Li, Ruo Zhang, Pingwen |
| Affiliation | Peking Univ, LMAM, CCSE, Beijing, Peoples R China. |
| Keywords | cellular automaton dendritic growth segregation continuum model melt convection PHASE-FIELD MODEL SOLIDIFICATION MICROSTRUCTURES GRAIN STRUCTURES ALLOYS PREDICTION SIMULATION INTERFACE PATTERNS |
| Issue Date | 2007 |
| Publisher | applied mathematical modelling |
| Citation | APPLIED MATHEMATICAL MODELLING.2007,31,(6),971-982. |
| Abstract | A two-dimensional model for the simulation of a binary dendritic growth with convection has been developed in order to investigate the effects of convection on dendritic morphologies. The model is based on a cellular automaton (CA) technique for the calculation of the evolution of solid/liquid (s/l) interface. The dynamics of the interface controlled by temperature, solute diffusion and Gibbs-Thomson effects, is coupled with the continuum model for energy, solute and momentum transfer with liquid convection. The solid fraction is calculated by a governing equation, instead of some approximate methods such as lever rule method [A. Jacot, M. Rappaz, Acta Mater. 50 (2002) 1909-1926.] or interface velocity method [L. Nastac, Acta Mater. 47 (1999) 4253; L. Beltran-Sanchez, D.M. Stefanescu, Mat. and Mat. Trans. A 26 (2003) 367.]. For the dendritic growth without convection, mesh independency of simulation results is achieved. The simulated steady-state tip velocity are corhpared with the predicted values of LGK theory [Lipton, M.E. Glicksmanm, W. Kurz, Metall. Trans. 18(A) (1987) 341.] as a function of melt undercooling, which shows good agreement. The growth of dendrite arms in a forced convection has been investigated. It was found that the dendritic growth in the upstream direction was amplified, due to larger solute gradient in the liquid ahead of the s/l interface caused by melt convection. In the isothermal environment, the calculated results under very fine mesh are in good agreement with the Oseen-1vanstov solution for the concentration-driven growth in a forced flow. (c) 2006 Elsevier Inc. All rights reserved. |
| URI | http://hdl.handle.net/20.500.11897/250463 |
| ISSN | 0307-904X |
| DOI | 10.1016/j.apm.2006.04.004 |
| Indexed | SCI(E) |
| Appears in Collections: | 科学与工程计算中心 数学及其应用教育部重点实验室 |
