Cold crucible melting of reactive metals using combined DC and AC magnetic fields
Bojarevics, Valdis, Pericleous, Koulis A., Harding, R and Wickins, M (2006) Cold crucible melting of reactive metals using combined DC and AC magnetic fields. In: The 5th International Symposium on Electromagnetic Processing of Materials (EPM 2006), October 23-27, 2006, Sendai, Japan.Full text not available from this repository.
Cold crucible furnace is widely used for melting reactive metals for high quality castings. Although the water cooled copper crucible avoids contamination, it produces a low superheat of the melt. Experimental and theoretical investigations of the process showed that the increase of the supplied power to the furnace leads to a saturation in the temperature rise of the melt, and no significant increase of the melt superheat can be obtained. The computer model of theprocess has been developed to simulate the time dependent turbulent flow, heat transfer with phase change, and AC and DC magnetohydrodynamics in a time varying liquid metal envelope. The model predicts that the supermimposition of a strong DC field on top of the normal AC field reduces the level of turbulience and stirring in the liquid metal, thereby reducing the heat loss through the base of the crucible and increasing the superheat. The direct measurements of the temperature in the commercial size cold crucbile has confirmed the computer redictions and showed that the addition of a DC field increased the superheat in molten TiAl from ~45C (AC field only) to ~81C (DC+AC fields). The present paper reports further predictions of the effect of a dDC field on top of the AC field and compares these with experimental data.
|Item Type:||Conference or Workshop Item (Paper)|
|Additional Information:||Invited paper|
|Uncontrolled Keywords:||cold crucible, liquid metal, AC electromagnetic field, turbulent flow, free surface dynamics, turbulent thermal losses, numerical modelling|
|Subjects:||Q Science > QA Mathematics|
Q Science > QD Chemistry
|School / Department / Research Groups:||School of Computing & Mathematical Sciences > Centre for Numerical Modelling & Process Analysis|
School of Computing & Mathematical Sciences
School of Computing & Mathematical Sciences > Department of Computer Systems Technology
School of Computing & Mathematical Sciences > Department of Mathematical Sciences
School of Computing & Mathematical Sciences > Centre for Numerical Modelling & Process Analysis > Computational Science & Engineering Group
|Last Modified:||31 Mar 2011 18:20|
Actions (login required)