Numerical simulation of solidification of liquid aluminum alloy flowing on cooling slope
Preparation of semisolid slurry using a cooling slope is increasingly becoming popular, primarily because of the.simplicity in design and ease control of the process. In this process, liquid alloy is poured down an inclined surface which is cooled from underneath. The cooling enables partial solidification and the incline provides the necessary shear for producing semisolid slurry. However, the final mierostrueture of the ingot depends on several process parameters such as cooling rate, incline angle of the cooling slope, length of the slope and initial melt superheat. In this work, a CFD model using volume of fluid (VOF) method for simulating flow along the cooling slope was presented. Equations for conservation of mass, momentum, energy and species were solved to predict hydrodynamic and thermal behavior, in addition to predicting solid fraction distribution and macrosegregation. Solidification was modeled using an enthalpy approach and a volume averaged technique for the different phases. The mushy region was modeled as a multi-layered porous medium consisting of fixed columnar dendrites and mobile equiaxed/fragmented grains. The alloy chosen for the study was aluminum alloy A356, for which adequate experimental data were available in the literature. The effects of two key process parameters, namely the slope angle and the pouring temperature, on temperature distribution, velocity distribution and maerosegregation were also studied.
simulation cooling slope slurry solidification A356 Al alloy semi-solid
N. K. KUND P. DUTTA
National Facility for Semisolid Forming, Department of Mechanical Engineering,Indian Institute of Science, Bangalore 560012, India
国际会议
北京
英文
898-905
2010-09-16（万方平台首次上网日期，不代表论文的发表时间）