SPLAT HEAT TRANSFER AND CRYSTAL GROWTH UNDER THERMAL SPRAY CONDITIONS

The impact process of a molten metal droplet impinging on a solid substrate surface is encountered in several technological applications such as ink-jet printing, spray cooling, coating processes, spray deposition of metal alloys, thermal spray coatings, manufacturing processes and fabrication and in industrial applications concerning thermal spray processes. Deposition of a molten material or metal in form of a droplet on a substrate surface by propelling it towards it forms the core of the spraying process. During the impact process, the molten metal droplet spreads radially and simultaneously starts losing heat due to heat transfer to the substrate surface. The associated heat transfer influences impingement behavior. The physics of droplet impingement is not only related to the fluid dynamics, but also to the respective interfacial properties of solid and liquid. For most applications, maximum spreading diameter of the splat is considered to be an important factor for droplet impingement on solid surfaces. In the present study, we have developed a model for droplet impingement based on energy conservation principle to predict the maximum spreading radius and the radius as a function of time. Further, we have used the radius as a function of time in the heat transfer equations and to study the evolution of splat-temperature and predict the spreading factor and the spreading time and mathematically correlate them to the spraying parameters and material properties.

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Coupling of conductive, convective and radiative heat transfer in Czochralski crystal growth process

Computational Materials Science ◽

10.1016/s0927-0256(02)00336-1 ◽

2002 ◽

Vol 25 (4) ◽

pp. 570-576 ◽

Cited By ~ 6

Author(s):

Andrzej J Nowak ◽

Ryszard A Białecki ◽

Adam Fic ◽

Gabriel Wecel ◽

Luiz C Wrobel ◽

...

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Radiative Heat Transfer ◽

Growth Process ◽

Radiative Heat ◽

Czochralski Crystal Growth ◽

Crystal Growth Process

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Non-isothermal effectiveness factors and the role of heat transfer in crystal growth from solutions and melts

Chemical Engineering Science ◽

10.1016/0009-2509(91)80128-l ◽

1991 ◽

Vol 46 (1) ◽

pp. 183-192 ◽

Cited By ~ 22

Author(s):

Masakuni Matsuoka ◽

John Garside

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Growth From Solutions ◽

Effectiveness Factors

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Extended Numerical and Analytical Model for Heat Transfer with and without Phase Change in non Ferric Powder for Thermal Spray Plasma Conditions

Journal of Physics Conference Series ◽

10.1088/1742-6596/511/1/012083 ◽

2014 ◽

Vol 511 ◽

pp. 012083

Author(s):

M De Abreu ◽

J Puerta ◽

F Blanco ◽

A Guerrero ◽

J Lira

Keyword(s):

Heat Transfer ◽

Phase Change ◽

Thermal Spray ◽

Analytical Model

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Radiation heat transfer of a Czochralski crystal growth furnace with arbitrary specular and diffuse surfaces

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(94)90062-0 ◽

1994 ◽

Vol 37 (12) ◽

pp. 1723-1731 ◽

Cited By ~ 15

Author(s):

Maruyama Shigenao ◽

Aihara Toshio

Keyword(s):

Heat Transfer ◽

Crystal Growth ◽

Radiation Heat Transfer ◽

Radiation Heat ◽

Czochralski Crystal Growth

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Effects of rotation on heat transfer, fluid flow and interfaces in normal gravity floating-zone crystal growth

Journal of Crystal Growth ◽

10.1016/0022-0248(91)90397-n ◽

1991 ◽

Vol 114 (4) ◽

pp. 517-535 ◽

Cited By ~ 38

Author(s):

C.W. Lan ◽

S. Kou

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Crystal Growth ◽

Normal Gravity ◽

Heat Transfer Fluid ◽

Floating Zone ◽

Effects Of Rotation

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Optimization of Bulk Hgcdte Growth in a Directional Solidification Furnace by Numerical Simulation

MRS Proceedings ◽

10.1557/proc-398-139 ◽

1995 ◽

Vol 398 ◽

Cited By ~ 1

Author(s):

A.V. Bune ◽

D.C. Gillies ◽

S.L. Lehoczky

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Finite Element ◽

Crystal Growth ◽

Numerical Model ◽

Directional Solidification ◽

Growth Conditions ◽

Finite Element Code ◽

Interface Shape ◽

Solidification Furnace

ABSTRACTA numerical model of heat transfer by combined conduction, radiation and convection was developed using the FIDAP finite element code for NASA's Advanced Automated Directional Solidification Furnace (AADSF). The prediction of the temperature gradient in an ampoule with HgCdTe is a necessity for the evaluation of whether or not the temperature set points for furnace heaters and the details of cartridge design ensure optimal crystal growth conditions for this material and size of crystal. A prediction of crystal/melt interface shape and the flow patterns in HgCdTe are available using a separate complementary model.

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