The modified chemical vapor deposition (MCVD) process is in wide use for the fabrication of optical fibers. One of the steps of the process is to deposit high purity chemicals on the inner surface of a fused silica tube to form doped silica glass layers. This is accomplished by passing a high purity gas mixture through the bore of a rotating silica tube. The tube is mounted in a glass-working lathe and is heated externally by a moving torch. The reagents are heated by the torch, causing a gas-phase reaction which results in the formation of submicron glassy particles. These particles travel along the tube and are deposited on the wall, downstream of the torch. Although the MCVD process is operational, the theoretical underpinnings are woefully weak. The objective of the proposed research is to provide a strengthened underpinning which should lead to more efficient operation. Features to be investigated include the effects of torch heating, torch speed, gas flow, tube rotation, and thermal radiation.
