Abstract
A mathematical model, which can predict the electromagnetic and temperature fields and also the shape of a molten silicon drop, has been developed for the improvement and determination of the optimal processing conditions in an electromagnetic levitation (EML) device recently developed to accurately measure the thermophysical properties of molten silicon. As a result, it was found that there exists an unstable state in which the drop was squeezed and then might be collapsed due to the electromagnetic force acting on the sample’s surface. Also, the results suggest that the shape of the molten material is not necessarily a perfect sphere under the microgravity environment because of the electromagnetic force due to the heating coil current.
Similar content being viewed by others
Abbreviations
- A′:
-
magnetic vector potential
- B′:
-
magnetic flux density
- A φ :
-
dimensionless azimuthal component of vector potential, A φ ′/(μ′0 J′ref r′ 2ref )
- Bo g :
-
Bond number, (ρ′g′r′ 2ref )/γ′
- Bo m :
-
electromagnetic Bond number, (μ′0 J′ref r′ 3ref )/γ′
- B S :
-
dimensionless magnetic intensity tangential to the surface of molten sample, B′ S /(μ′0 J′ref r′ref)
- f :
-
dimensionless radial distance, f′/r′ref
- 2H :
-
dimensionless mean curvature, 2H′r′ref
- h :
-
dimensionless relative position between coils and sample, h′/r′ref
- J :
-
dimensionless current density, J′/J′ ref
- k :
-
dimensionless thermal conductivity, k′/k′ ref
- N A :
-
dimensionless number defined by μ′0 θ′ f σ′ ref r′ 2ref
- N Q :
-
dimensionless number defined by (σ′ref θ′ 2 f ′ 20 J′ 2ref r′ 2ref )/(k′ref T′m)
- n :
-
dimensionless normal direction, n′/r′ ref
- Ra:
-
Radiation number, (ε′ σ′ref T′ 3 m r′ref)/k′ref
- r :
-
dimensionless radial coordinate, r′/r′ ref
- T :
-
dimensionless temperature, T′/T′ m
- T′ m :
-
melting temperature of silicon
- t′:
-
time
- z :
-
dimensionless axial coordinate, z′/r′ ref
- α :
-
dimensionless electric conductivity, σ′/σ′ ref
- γ′:
-
surface tension
- ε′:
-
emissivity
- ϑ′:
-
polar angle
- λ :
-
dimensionless reference pressure difference, (r′ref ΔP′)/γ′
- μ′0 :
-
magnetic permeability
- σ′:
-
electric conductivity
- ρ′:
-
density
- ω′:
-
angular frequency
- C :
-
coil
- a :
-
environment
- f :
-
frequency
- ref:
-
reference value
- φ:
-
azimuthal component
- ′:
-
dimensional value
- *:
-
complex conjugate
References
O. Muck: German Patent No. 422,004, Oct. 30, 1923.
S. Asai: Electromagnetic Processing of Materials, ISIJ, Nagoya, Japan, 1994.
Y. Bayazitoglu, P.V.R. Suryanarayana, and U.B. Sathuvalli: AIAA J. Thermophys. Heat Transfer, 1990, vol. 44, pp. 462–68.
J. Murphy and Y. Bayazitoglu: Numer. Heat Transfer Pt. A, 1992, vol. 22, pp. 10–120.
B.J. Keene, K.C. Mills, A. Kasama, A. Mclean, and W.A. Miller: Metall. Trans. B, 1986, vol. 17B, pp. 159–62.
Y. Bayazitoglu and P.V.R. Suryanarayana: AIAA J. Thermophys. Heat Transfer, 1989, vol. 43, pp. 351–53.
I. Egry, G. Lohöfer, P. Neuhaus, and S. Saverland: Int. J. Thermophys., 1992, vol. 13, pp. 65–74.
M. Przyborowski, T. Hibiya, M. Eguchi, and I. Egry: J. Crystal Growth, 1995, vol. 151, pp. 60–65.
E. Gorges, L.M. Racz, A. Schillings, and I. Egry: Int. J. Thermophys., 1996, vol. 17, pp. 1163–72.
G. Lohöfer, P. Neuhaus, and I. Egry: High Temperatures-High Pressures, 1991, vol. 23, pp. 333–42.
I. Egry, G. Jacobs, E. Schwartz, and J. Szekely: Int. J. Thermophys., 1996, vol. 75, pp. 1181–89.
I. Egry and J. Szekely: Adv. Space Rec., 1991, vol. 11, pp. 263–66.
E.C. Okress, D.M. Wroughton, G. Comenetz, P.H. Brace, and J.C.R. Kelly: J. Appl. Phys., 1952, vol. 23, pp. 545–52.
G. Lohöfer: SIAM J. Appl. Math., 1989, vol. 49, pp. 567–81.
Y. Bayazitoglu and U.B. Sathuvalli: IEEE Trans. Magn., 1993, vol. 29, pp. 88–97.
U.B. Sathuvalli and Y. Bayazitoglu: Metall. Trans. B, 1993, vol. 24B, pp. 737–48.
N. El-Kaddah and J. Szekely: Metall. Trans. B, 1983, vol. 14B, pp. 401–10.
N. El-Kaddah and J. Szekely: Metall. Trans. B, 1984, vol. 15B, pp. 183–86.
A. Gagnoud and M. Garnier: IEEE Trans. Magn., 1985, vol. 21, pp. 1886–88.
A. Gagnoud, J. Etay, and M. Garnier: J. Theor. Appl. Mech., 1986, vol. 5, pp. 911–34.
A. Gagnoud and I. Leclercq: IEEE Trans. Magn., 1988, vol. 24, pp. 256–58.
J.-H. Zong, J. Szekely, and E. Schwartz: IEEE Trans. Magn., 1993, vol. 28, pp. 1833–42.
A.J. Mestel: J. Fluid Mech., 1982, vol. 17, pp. 27–43.
A.D. Sneyd and H.K. Moffatt: J. Fluid Mech., 1982, vol. 117, pp. 45–70.
J.-H. Zong, B. Li, and J. Szekely: Acta Astronautica, 1992, vol. 26, pp. 435–49.
J.-H. Zong, B. Li, and J. Szekely: Acta Astronautica, 1993, vol. 29, pp. 305–11.
J.-H. Zong and J. Szekely: Acta Astronautica, 1993, vol. 29, pp. 371–78.
P.V.R. Suryanarayana and Y. Bayazitoglu: Phys. Fluid A, 1991, vol. 3, pp. 967–77.
A. Bratz and I. Egry: J. Fluid Mech., 1995, vol. 298, pp. 341–59.
Y. Bayazitoglu, U.B.R. Sathuvalli, P.V.R. Suryanarayana, and G.F. Mitchell: Phys. Fluid, 1996, vol. 8, pp. 370–83.
J. Shinohara, H. Ueno, S. Iwasaki, E. Nishizawa, H. Sakurai, K. Nogi, and S. Kitagawa: J. Soc. Microgravity Application, 1996, vol. 13, pp. 165–66.
T. Hibiya: J. Soc. Microgravity Application, 1996, vol. 13, pp. 5–8.
T. Miyoshi, M. Sumiya, and H. Omori: IEEE Trans. Magn., 1987, vol. 23, pp. 1827–32.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hahn, S.H., Sakai, Y., Tsukada, T. et al. Effect of processing conditions on drop behavior in an electromagnetic levitator. Metall Mater Trans B 29, 223–228 (1998). https://doi.org/10.1007/s11663-998-0025-y
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11663-998-0025-y