Combustion Characteristics in Growth Chamber for Verneuilgrown Rutile Crystal

Combustion characteristics of three-tube burner in growth chamber for preparation of single crystal by the Verneuil method were investigated, and the effects of nozzle structure and flow rate on the surface temperature of molten cap were analyzed. The results showed that hydrogen flowed out from the nozzle diffused with inner and outer oxygen, and two flame produced in the center and near the wall of growth chamber. The surface temperature of molten cap were gradually reduced from the center outward. The temperature of molten cap decreased gradually with increasing the nozzle aperture of inner oxygen, and varied slightly with the diameter of hydrogen and outer oxygen nozzle. The temperature of molten cap decreased gradually with increasing the flow rate of inner and outer oxygen, while increased with the flow rate of hydrogen.