ISSN Online: 2377-424X
International Heat Transfer Conference 12
Thermal design of draw furnace in optical fiber manufacturing
Sinopsis
An optimal design of the draw furnace is desirable to meet the need of high-volume production in the
optical fiber industry. This paper investigates optical fiber drawing at high draw speeds in a cylindrical
graphite furnace. A conjugate problem involving the glass and the purge gases is considered. The transport in
the two regions is coupled through the boundary conditions at the free glass surface. The neckdown profile of
the preform at steady state is determined by a force balance,using an iterative numerical scheme. The effects
of the thermal configuration for a graphite draw furnace are investigated for fixed preform and fiber
diameters. Various temperature distributions along the furnace wall are considered to investigate the thermal
and flow transport within the furnace. For the purposes of comparison, two moderate draw speeds, 5 m/s and
15 m/s,are used. The dependence of the preform/fiber characteristics on the furnace thermal configuration is
determined.