Numerical investigation of the vortex formation in a liquid metal under the action of disk agitator

M. G. Khmeleva   ; V. Kh. Dammer   ; A. B. Tokhmetova   ; L. L. Min'kov

Vestnik Tomskogo gosudarstvennogo universiteta. Matematika i mehanika, no. 46 (2017), pp. 76-85

Résumé

A numerical study of the molten metal flow in a crucible under the action of a rotating agitator of a special shape has been performed. The turbulent flow field is described using the $k-\varepsilon$ turbulence model. The position of the air-liquid metal interface was determined by the VOF method. The set of governing equations written in the frame of reference associated with the rotating agitator was solved using the ANSYS Fluent software. The convergence of the numerical solution with a mesh refinement has been demonstrated. The patterns of the molten metal flow in the crucible for different agitator speeds of rotation have been obtained. The dependences of turbulent diffusion, size of turbulent eddies, and power criterion on the speed of rotation of the agitator have been defined. The effect of interaction between the metal-air interface and elements of the agitator on the flow pattern of molten metal in the crucible has been investigated. It is shown that the conditions under which elements of the agitator are completely immersed in the liquid metal are more favorable for the formation of small vortices than the conditions under which the liquid metal-air interface interacts with agitator elements.

Détail

Keywords: molten metal flow, turbulence flow, disk agitator
Mots-clés : diffusion coefficient.

Bibliographie

[1] Kafarov V. V., Fundamentals of mass transfer, Vysshaya shkola, M., 1962, 655 pp.

[2] Strek F., Mixing and apparatuses with agitators, Khimiya, L., 1975, 384 pp.

[3] Braginskiy L. N., Begachev V. I., Barabash V. N., Mixing in liquid media: Physical fundamentals and engineering methods of calculation, Khimiya, L., 1984, 336 pp.

[4] Chhabra R. P., Richardson J. F., Non-Newtonian Flow and Applied Rheology. Engineering Applications, Elsevier, Oxford, 2008, 518 pp.

[5] Wojtowicz R., Lipin A. A., Talaga J., “On the possibility of using of different turbulence models for modeling flow hydrodynamics and power consumption in mixing vessels with turbine impellers”, Theoretical Foundations of Chemical Engineering, 48:4 (2014), 360–375 | DOI | DOI

[6] Wojtowicz R., Lipin A. A., Lipin A. G., “Numerical simulation of hydrodynamics of mixer with eccentrically positioned impeller”, Chemistry and Chemical Technology, 58:11 (2015), 83–86

[7] Torre J. P., Fletcher D. F., Lasuye T., Xuereb C., “An experimental and computational study of the vortex shape in a partially baffled agitated vessel”, Chemical Engineering Science, 62 (2007), 1915–1926 | DOI

[8] Hristov H. V., Boden S., Hampel U., Kryk H., Hessel G., Schmitt W., “A study on the two-phase flow in a stirred tank reactor agitated by a gas-inducing turbine”, Chemical engineering research and design, 86 (2008), 75–81 | DOI

[9] Vorozhtsov A. B., Arkhipov V. A., Shrager E. R., Dammer V. Ch., Vorozhtsov S. A., Khmeleva M. G., Device for mixing liquids and powders with liquid, RF Patent 2016130836

[10] Youngs D. L., “Time-dependent multi material flow with large fluid distortion”, Numerical Modeling for Fluid Dynamics, eds. Morton K. W., Baines M. J., Academic Press, New York, 1982, 273–285 | MR

[11] Patankar S., Numerical heat transfer and fluid flow, Hemisphere Publ. Corp., Washington, 1980 | Zbl

[12] ANSYS FLUENT Tutorial Guide: Release 14.0, ANSYS Inc., 2011

[13] Garbaruk A. B., Strelets M. Kh., Shur M. L., Modeling of turbulence in calculations of complex flows, tutorial, Izd-vo Politechnicheskogo Universiteta, St. Petersburg, 2012, 88 pp.