A comprehensive model is developed to study the heating, melting, evaporation, and resolidification of powder particles in plasma flames. The well-established LAVA code for plasma flame simulation is used to predict the plasma gas field under given power conditions, and provide inputs to the particle model. The particle is assumed to be a spherical and one-dimensional heat conduction equation with phase change within the particle is solved numerically using an appropriate coordinate transformation and finite difference method. Melting, vaporization, and resolidification interfaces are tracked and the particle vaporization is accounted for by the mass diffusion of vapor through the boundary layer around the particle. The effect of mass transfer on convective heat transfer is also included. Calculations have been carried out for a single particle injected into an Ar–H2 plasma jet. Zirconia and nickel are selected as solid particles because of their widespread industrial applications as well as significant differences in their thermal properties. Numerical results show strong nonisothermal effect of heating, especially for materials with low thermal conductivity, such as zirconia. The model also predicts strong evaporation of the material at high temperatures.
Issue Section:
Heat Transfer in Manufacturing
1.
Anselmo, A., Prasad, V., and Koziol, J., 1991, “Melting of a Sphere when Dropped in a Pool of Melt with Applications to Partially-Immersed Silicon Pellets,” 27th National Heat Transfer Conf., Minneapolis.
2.
Boulos, M. I., Fauchais, P., Vardelle, A., and Pfender, E., 1993, “Fundamentals of Plasma Particle Momentum and Heat Transfer,” Plasma Spraying, R. Suryanarayanan, ed., World Scientific, Singapore, pp. 3–57.
3.
Boulos, M. I., Fauchais, P., and Pfender, E., 1994, Thermal Plasmas, Fundamentals and Applications, Vol. 1, Plenum Press, New York, p. 367, 372.
4.
Chang
C. H.
Ramshaw
J. D.
1993
, “Numerical Simulations of Argon Plasma Jets Flowing into Cold Air
,” Plasma Chemistry and Plasma Processing
, Vol. 13
, No. 2
, pp. 189
–209
.5.
Chang
C. H.
Ramshaw
J. D.
1996
, “Modeling of nonequilibrium effects in a High-Velocity Nitrogen-Hydrogen Plasma Jet
,” Plasma Chemistry and Plasma Processing (Supplement)
, Vol. 16
, No. 1
, pp. 5S–17S
5S–17S
.6.
Chen
X.
Pfender
E.
1982
, “Heat Transfer to a Single Particle Exposed to a Thermal Plasma
,” Plasma Chemistry and Plasma Processing
, Vol. 2
, No. 2
, pp. 185
–212
.7.
Chen
X.
Pfender
E.
1983
a, “Effect of the Knudsen Number on Heat Transfer to a Particle Immersed into a Thermal Plasma
,” Plasma Chemistry and Plasma Processing
, Vol. 3
, No. 1
, pp. 97
–112
.8.
Chen
X.
Pfender
E.
1983
b, “Behavior of Small Particles in a Thermal Plasma Flow
,” Plasma Chemistry and Plasma Processing
, Vol. 3
, No. 3
, pp. 351
–366
.9.
Das
D. K.
Sivakumar
R.
1990
, “Modeling of the Temperature and the Velocity of Ceramic Powder Particles in A Plasma Flame-I. Alumina
,” Acta Metall. Mater.
, Vol. 38
, No. 11
, pp. 2187
–2192
.10.
Faeth
G. M.
1983
, “Evaporation and Combustion of Sprays
,” Prog. Energy Combust. Sci.
, Vol. 9
, pp. 1
–76
.11.
Fiszdon
J. K.
1979
, “Melting of Powder Grains in a Plasma Flame
,” Int. J. Heat Mass Transfer
, Vol. 22
, pp. 749
–761
.12.
Groma
I.
Veto
B.
1986
, “Melting of Powder Grains in Plasma Spraying
,” Int. J. Heat Mass Transfer
, Vol. 29
, No. 4
, pp. 549
–554
.13.
Hultgen, R., Desai, P. D., Hawkins, D. T., Gleiser, M., Kelley, K. K., and Wagman, D. D., 1973, Selected Values of the Thermodynamics Properties of the Elements, American Society of Metals.
14.
Launder, B. E., and Spalding, D. B., 1972, Mathematical Models of Turbulence, Academic Press, New York.
15.
Law
C. K.
1982
, “Recent Advances in Droplet Vaporization and Combustion
,” Prog. Energy Combust. Sci.
, Vol. 8
, pp. 171
–201
.16.
Lee
H. E.
1988
, “Heat Transfer of Particles in Plasma Flow
,” J. Phys. D: Appl. Phys.
, Vol. 21
, pp. 73
–78
.17.
Lee, Y. C., Hsu, K. C., and Pfender, E., 1981, “Modeling of Particles Injected into a d.c. Plasma Jet,” Proc. 5th Int. Symposium on Plasma Chemistry, Vol. 2, p. 795.
18.
Pfender
E.
Lee
Y. C.
1985
, “Particle Dynamics and Particle Heat and Mass Transfer in Thermal Plasma, Part I, The Motion of a Single Particle without Thermal Effects
,” Plasma Chemistry and Plasma Processing
, Vol. 5
, No. 3
, pp. 211
–237
.19.
Proulx
P.
Mostaghimi
J.
Boulos
M. I.
1985
, “Plasma-particle Interaction Effects in Induction Plasma Modeling under Dense Loading Conditions
,” Int. J. Heat Mass Transfer
, Vol. 28
, No. 7
, pp. 1327
–1336
.20.
Ramshaw
J. D.
Chang
C. H.
1993
, “Computational Fluid Dynamics Modeling of Multi-component Thermal Plamsmas
,” Plasma Chemistry and Plasma Processing
, Vol. 12
, No. 3
, pp. 299
–325
.21.
Ramshaw
J. D.
Chang
C. H.
1995
, “Iteration Scheme for Implicit Calculations of Kinetics and Equilibrium Chemical Reactions in Fluid Dynamics
,” J. of Computational Physics
, Vol. 116
, pp. 359
–364
.22.
Ranz
W. E.
Marshall
W. R.
1952
, “Evaporation from Drops
,” Chem. Engrg. Prog.
, Vol. 48
, No. 3
, pp. 141
–173
.23.
Samsonov, G. V., 1973, The Oxide Handbook, Plenum, New York (translation from Russian).
24.
Smith, W., Jewett, T. J., Sampath, S., Swank, W. D., and Fincke, J. R., 1997, “Plasma Processing of Functionally Graded Materials Part I: Process Diagnostics,” Proc. United Thermal Spray Conf., C. C. Berndt, ed., ASM International, Materials Park, OH, pp. 599–605.
25.
Solomon
A. D.
1979
, “Melt Time and Heat Flux for a Simple PCM Body
,” Solar Energy
, Vol. 22
, pp. 251
–257
.26.
Vardelle
A.
Themelis
N. J.
Dussoubs
B.
Vardelle
M.
Fauchais
P.
1997
, “Transport and Chemical Rate Phenomena in Plasma Sprays
,” J. of High Temp. Proc.
, Vol. 1
, No. 3
, pp. 295
–314
.27.
Wan, Y. P., Prasad, V., Wang, G.-X., Sampath, S., and Fincke, J. R., 1998, “Modeling of Powder Particle Heating, Melting and Evaporation in Plasma Spraying Progresses,” Proc. ASME Heat Transfer Division, Vol. 4, HTD-Vol. 361-4, ASME, New York, pp. 67–77.
28.
Wang
G.-X.
Matthys
E. F.
1996
, “Modeling of Nonequilibrium Surface Melting and Resolidification for Pure Metals and Binary Alloys
,” ASME JOURNAL OF HEAT TRANSFER
, Vol. 118
, pp. 944
–951
.29.
Wang
G.-X.
Prasad
V.
Matthys
E. F.
1997
, “An Interface-tracking Numerical Method for Rapid Planar Solidification of Binary Alloys with Application to Microsegregation
,” Materials Science & Engineering
, Vol. A225
, pp. 47
–58
.30.
Wei
D. Y. C.
Farouk
B.
Apelian
D.
1987
, “Melting Powder Particles in a Low-Pressure Plasma Jet
,” ASME JOURNAL OF HEAT TRANSFER
, Vol. 109
, pp. 971
–976
.31.
Wei
D. Y. C.
Farouk
B.
Apelian
D.
1988
, “Melting Metal Powder Particles in an Inductively Coupled R. F. Plasma Torch
,” Metall. Trans. B
, Vol. 19B
, pp. 213
–226
.32.
Westhoff
R.
Trapaga
G.
Szekely
J.
1992
, “Plasma-Particle Interactions in Plasma Spraying Systems
,” Metall. Trans. B
, Vol. 23B
, pp. 683
–693
.33.
White, F. M., 1974, Viscous Fluid Flow, McGraw-Hill, New York.
34.
Williams, F. A., 1985, Combustion Theory, 2nd Ed., Addison-Weslay, New York, p. 380.
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