【摘 要】
：
A two-dimensional coupling modified cellular automaton (MCA)-transport model has been employed to investigate the asymmetrical dendritic growth behavior in a fl
【机 构】
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Department of Materials Science and Engineering,Center for Computer-Aided Materials Processing CAMP
【基金项目】
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国家自然科学基金;教育部留学回国人员科研启动基金
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A two-dimensional coupling modified cellular automaton (MCA)-transport model has been employed to investigate the asymmetrical dendritic growth behavior in a flowing melt. In the present model, the cellular automaton method for crystal growth is incorporated with a transport model, for numerical calculating of the fluid flow and mass transport by both convection and diffusion. The MCA takes into account the effects of the thermal, the constitutional and the curvature undercoolings on dendritic growth. It also considers the preferred growth orientation of crystal and solute redistribution during solidification. In the transport model, the SIMPLE scheme and a fully implicit finite volume method are employed to solve the governing equations of momentum and species transfers. The present model was applied to simulating the evolution of a single dendrite and multi-dendrites of an Al-3mass%Cu alloy in a forced flow. The simulated results show that dendritic growth morphology is strongly influenced by melt convection.
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