Optimising Computational Fluid Dynamic Conditions for Simulating Copper Vertical Casting

Abstract:

A 2-D finite volume Computational Fluid Dynamic (CFD) model, using Ansys Fluent vR.1 of a vertically oriented upwards continuous casting (VUCC), was investigated for 8 mm, oxygen free copper (OFCu). The simulations enabled the mapping of the cast OFCu solidification front (SF) interface from liquid to solid. Optimisation of the simulation parameters were investigated which included mesh size and the Ansys specific ‘mushy zone’ constant (A_mush), which is used to account for fluid flow dampening at SF within the model. Observations of the SF, the change in fluid volume in the die, the simulation convergence and the total simulation time, revealed that the optimised casting parameters were for mesh size 1×10^-4 m and A_mush 10⁶ kg/m³s. These parameters were compared with the cast rod and highlighted qualitatively the relationship between grain growth direction and SF position during a casting pulse cycle.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 642-647
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.642
• Online since: January 2021
• Authors: Thomas David Arthur Jones*, Richard I. Strachan, David M. Mackie, Mervyn Cooper, Brian Frame, Jan B. Vorstius
• Keywords: Casting, CFD, Copper Alloy, Grain Structure, Mesh Size, Pushback

References

[1] H. Soda, G. Motoyasu, A. McLean, S. D. Bagheri, and D. D. Perovic, Continuous casting of unidirectionally solidified copper rod,, Int. J. Cast Met. Res., vol. 9, no. 1, p.37–44, May (1996).

DOI: 10.1080/13640461.1996.11819642

[2] K. Härkki and J. Miettinen, Mathematical modeling of copper and brass upcasting,, Metall. Mater. Trans. B, vol. 30, no. 1, p.75–98, Feb. (1999).

DOI: 10.1007/s11663-999-0009-6

[3] H. R. Müller, Continuous Casting: Proceedings of the International Conference on Continuous Casting of Non-Ferrous Metals. Wiley, (2006).

DOI: 10.1002/9783527607969.ch45

[4] D. Mackie, J. D. Robson, P. J. Withers, and M. Turski, Characterisation and modelling of defect formation in direct-chill cast AZ80 alloy,, Mater. Charact., vol. 104, p.116–123, (2015).

DOI: 10.1016/j.matchar.2015.03.033

[5] B. Yang, A. Raza, F. Bai, T. Zhang, and Z. Wang, Microstructural evolution within mushy zone during paraffin's melting and solidification,, Int. J. Heat Mass Transf., vol. 141, p.769–778, (2019).

DOI: 10.1016/j.ijheatmasstransfer.2019.07.019

[6] Z. Boz, F. Erdogdu, and M. Tutar, Effects of mesh refinement, time step size and numerical scheme on the computational modeling of temperature evolution during natural-convection heating,, J. Food Eng., vol. 123, p.8–16, (2014).

DOI: 10.1016/j.jfoodeng.2013.09.008

[7] E.-R. Bagherian, Y. Fan, M. Cooper, B. Frame, and A. Abdolvand, Effect of water flow rate, casting speed, alloying elements and pull distance on tensile strength, elongation percentage and microstructure of continuous cast copper alloys,, Met. Res. Technol., vol. 113, no. 3, p.308, (2016).

DOI: 10.1051/metal/2016006

[8] L. Nastac, K. Pericleous, A. S. Sabau, L. Zhang, and B. G. Thomas, CFD Modeling and Simulation in Materials Processing 2018. Springer International Publishing, (2018).

DOI: 10.1007/978-3-319-72059-3

[9] Ansys, Ansys Theory Guide, Release 15.0. (2013).

[10] M. Fadl and P. C. Eames, Numerical investigation of the influence of mushy zone parameter Amush on heat transfer characteristics in vertically and horizontally oriented thermal energy storage systems,, Appl. Therm. Eng., vol. 151, p.90–99, (2019).

DOI: 10.1016/j.applthermaleng.2019.01.102

[11] ASTM International, ASTM E112-13, Standard Test Methods for Determining Average Grain Size,, (2013).

[12] K. Liu, C. Wang, G. Liu, D. Ning, S. Qi-song, and Zhi-hongTian., Research on Soft Reduction Amount Distribution to Eliminate Typical Inter-dendritic Crack in Continuous Casting Slab of X70 Pipeline Steel by Numerical Model,, High Temp. Mater. Process., vol. 36, no. 4, p.359–372, (2017).

DOI: 10.1515/htmp-2016-0160

[13] M. Hameter and H. Walter, Influence of the Mushy Zone Constant on the Numerical Simulation of the Melting and Solidification Process of Phase Change Materials,, in 26 European Symposium on Computer Aided Process Engineering, vol. 38, Z. Kravanja and M. B. T.-C. A. C. E. Bogataj, Eds. Elsevier, 2016, p.439–444.

DOI: 10.1016/b978-0-444-63428-3.50078-3