Investigation on the Surface Vortex Formation During Mechanical Stirring with an Axial-Flow Impeller Used in an Aluminum Process
- 52 Downloads
The present study investigated the mechanism of surface vortex formation in an aluminum melt vessel stirred by an axial-flow impeller mechanically. The oxide film is formed at the aluminum melt/air interface, and the movement of the interface entrains the oxide film and inclusions. Hence, the transient movement of melt–air interface is significant. The present study conducted a water model experiment and numerical simulation focusing on the movement of gas–liquid interface. The present study found that the oxide film can be entrained by two phenomena: (1) local surface vortex and (2) sloshing near the vessel wall. The local surface vortex is formed due to the pressure distribution around the impeller, and the sloshing is caused by macroinstabilities, which is generated by the discharged flow of axial-flow impeller. Besides, the shape of gas–liquid interface is dependent on the impeller shape. The axial-flow impeller gives rise to steeply curved shape of gas–liquid interface near the impeller shaft.
The present research is supported partly by the Initiative on Promotion of Supercomputing for Young or Women Researchers, Supercomputing Division, Information Technology Center, The University of Tokyo.
- 1.M. E. Schlesinger (2014) Aluminum Recycling, 2nd edition. CRC Press, Boca Raton.Google Scholar
- 2.J.-F. Bilodeau and Y. Kocaefe: in Light Metals, TMS, New York, 2001, pp. 1009–1015.Google Scholar
- 3.L.I. Kiss and J.F. Bilodeau: Proceedings of Conference on Metallurgists, 2001, Toronto.Google Scholar
- 5.J.L. Song, M.R. Jolly, M. Kimata, W. Bujalski, and A.W. Nienow: in Proceesings of Third International Conference on CFD in the Minerals and Process Industries, 2003, pp. 65–70, Melbourne, Australia, 10–12 December 2003.Google Scholar
- 13.M. Saternus: J. Achiev. Mater. Manuf. Eng., 2012, vol. 55, pp. 285-290.Google Scholar
- 25.S. Nagata: Mixing: Principles and applications, 1975, Halsted Press, New York.Google Scholar
- 30.H.G. Weller: Technical Report. TR/HGW/04, OpenCFD Ltd., 2008.Google Scholar
- 31.H. Rusche: Computational Fluid Dynamics of Dispersed Two-Phase Flows at High Phase Fractions, Ph.D. thesis, Imperial Collage of Science, Technology and Medicine, London, 2002.Google Scholar
- 33.H. K. Versteeg, W. Malalasekera: An introduction to computational fluid dynamics, the finite volume method, Longman Group Ltd., Harlow, 1995.Google Scholar