A three-dimensional analysis of particle deposition for the modified chemical vapor deposition (MCVD) process

Journal Article · Sat Aug 01 00:00:00 EDT 1992 · Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States)

DOI:https://doi.org/10.1115/1.2911342· OSTI ID:6987420

Lin, Y T; Choi, M; Greif, R ^[1]

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1. Univ. of California, Berkeley (United States)

A study has been mode of the deposition of particles that occurs during the modified chemical vapor deposition (MCVD) process. The three-dimensional conservation equations of mass, momentum, and energy have been solved numerically for forced flow, including the effects of buoyancy and variable properties in a heated, rotating tube. The motion of the particles that are formed is determined from the combined effects resulting from thermophoresis and the forced and secondary flows. The effects of torch speed, rotational speed, inlet flow rate, tube radius, and maximum surface temperature on deposition are studied. IN a horizontal tube, buoyancy results in circumferentially nonuniform temperature and velocity fields and particle deposition. The effect of tube rotation greatly reduces the nonuniformity of particle deposition in the circumferential direction. The process is chemical-reaction limited at larger flow rates and particle-transport limited at smaller flow rates. The vertical tube geometry has also been studied because its symmetric configuration results in uniform particle deposition in the circumferential direction. The 'upward' flow condition results in a large overall deposition efficiency, but this is also accompanied by a large 'tapered entry length'.

• OSTI ID: 6987420
• Journal Information: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States), Vol. 114:3; ISSN 0022-1481
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL VAPOR DEPOSITION
MATHEMATICAL MODELS
PARTICULATES
DEPOSITION
CHEMICAL REACTION KINETICS
EFFICIENCY
MOTION
NATURAL CONVECTION
THERMOPHORESIS
CHEMICAL COATING
CONVECTION
ENERGY TRANSFER
HEAT TRANSFER
KINETICS
MASS TRANSFER
PARTICLES
REACTION KINETICS
SURFACE COATING
360101* - Metals & Alloys- Preparation & Fabrication
360201 - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360601 - Other Materials- Preparation & Manufacture