Numerical simulation on dendritic growth of Al-Cu alloy under convection based on the cellular automaton lattice Boltzmann method  

作　　者：Kang-Wei Wang Meng-Wu Wu Bing-Hui Tian Shou-Mei Xiong 王康伟;吴孟武;田冰辉;熊守美(School of Automotive Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology,Wuhan 430070,China;School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]School of Automotive Engineering,Wuhan University of Technology,Wuhan 430070,China [2]Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology,Wuhan 430070,China [3]School of Materials Science and Engineering,Tsinghua University,Beijing 100084,China

出　　处：《Chinese Physics B》2022年第9期575-586,共12页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.51805389);the Key R&D Program of Hubei Province,China(Grant No.2021BAA048);the 111 Project(Grant No.B17034);the fund of Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology(Grant No.XDQCKF2021011).

摘　　要：A numerical model is developed by coupling the cellular automaton(CA)method and the lattice Boltzmann method(LBM)to simulate the dendritic growth of Al-Cu alloy in both two and three dimensions.An improved decentered square algorithm is proposed to overcome the artificial anisotropy induced by the CA cells and to realize simulation of dendritic growth with arbitrary orientations.Based on the established CA-LBM model,effects of forced convection and gravity-driven natural convection on dendritic growth are studied.The simulation results show that the blocking effect of dendrites on melt flow is advanced with a larger number of seeds.The competitive growth of the converging columnar dendrites is determined by the interaction between heat flow and forced convection.Gravity-driven natural convection leads to highly asymmetric growth of equiaxed dendrites.With sinking downwards of the heavy solute,chimney-like or mushroom-like solute plumes are formed in the melt in front of the columnar dendrites when they grow along the gravitational direction.More details on dendritic growth of Al-Cu alloy under convection are revealed by 3D simulations.

关 键 词：SIMULATION cellular automaton dendritic growth melt convection 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TP301.1[金属学及工艺—金属材料]