The simulation software has been validated using our experimental data and results published in [4], [5], [6].
The value of Niyama criterion and porosity module of the software has been calibrated using a cut ingot [14] as seen in the figure below:

a. Solidification isotherms b. Axial porosity c. Axial porosity in cut ingot [14]

Figure 9. Axial porosity comparison between simulation and 8T cut ingot


References

[1] Industrial Soft: Online Ingot Mould Design Assistant v.1.0, www.simcade.com
[2] Industrial Soft: SIMCADE v.2.0, Solidification Simulation Software; www.simcade.com
[3] Flemings, M.C.: Our Understanding of Macrosegregation: Past and Present, ISIJ International, Vol. 40 (2000), No. 9, pp. 833–841, 2000
[4] Delorme, J.; Laubin, M., Maas H.; Solidification of Large Forging Ingots, Casting and Solidification of Steel vol.1, ECSC Luxembourg 1977
[5] Lesoult G.: Macrosegregation in steel strands and ingots: Characterization, formation and consequences, Mater. Sci. Eng. A, 413-414 (2005), pp. 19-29.
[6] Kajikawa K., Suzuki S.: Development of 650-ton-class ingot for turbine rotor shaft forging application, ICRF, 2012
[7] Suzuki, K.; Miyamoto, T.: Formation Condition of “A” Segregation, Tetsu-to-Hagane. 63. 53-62, 1977
[8] Yamada, H.; Sakurai T.; Takenouchi, T.: Critical Conditions for the Formation of A-Segregation in Forging Ingots; ISIJ, 1989, p.92-104
[9] Suzuki, K.; Miyamoto, T.: Influence of Alloying Elements on the Formation of A-Segregates In Steel Ingots, Tetsu-to-Hagane, 1979 Volume 65 Issue 10 Pages 1571-1580
[10] Yamada H., Sakurai T., Takenouchi T.: Appearance of "A" Segregation in Forging Ingots and Influencing Factors, 1989 Volume 75 Issue 1 Pages 105-112
[11] Iida Y. et al.: Development of Hollow Ingot for Large Forging, Tetsu-to-Hagane 1980 Volume 66 Issue 2 Pages 211-220
[12] Haida, O.; Okano, S.; Emi, T.; Kasai, G.: Estimation of the Formation of A-Segregation in Steel Ingot in Terms of the Chemical Composition of Steel; ISIJ, 1981, p.954-958
[13] Suzuki K., Taniguchi K.: The Elimination Mechanism of A-Segregates of Steel Ingot, 1979 Volume 65 Issue 10 Pages 1581-1588
[14] Martin Balcar et all : Developing and Testing a New Type-8k Mould For Tool-Steel Ingot Casting, Materials and Technologies 42(1):33-38 • January 2008