Abstract: Disclosed is a burner register assembly having an air register assembly for imparting a controlled vortex swirl to secondary combustion air of a furnace in order to entrain the fuel and primary air of the furnace and carry them into the furnace interior. The assembly may comprise a series of arcuate vanes circumferentially spaced about the fuel and primary air nozzle, the vanes being designed to induce both turbulence and a well defined vortex to the secondary air flow. A separate air valve, such as a butterfly valve, is provided upstream of the air register assembly to regulate the volume of secondary air flow. Shadow vanes may also be provided in the vicinity of the air register assembly outlet, and positioned adjacent the furnace walls in order to protect the air register assembly from furnace heat, particularly when the burner associated with the air register assembly is idle and the secondary air flow is lowered.

Abstract: Disclosed is a burner register assembly having an air register assembly for imparting a controlled vortex swirl to secondary combustion air of a furnace in order to entrain the fuel and primary air of the furnace and carry them into the furnace interior. The assembly may comprise a series of arcuate vanes circumferentially spaced about the fuel and primary air nozzle, the vanes being designed to induce both turbulence and a well defined vortex to the secondary air flow. A separate air valve, such as a butterfly valve, is provided upstream of the air register assembly to regulate the volume of secondary air flow. Shadow vanes may also be provided in the vicinity of the air register assembly outlet, and positioned adjacent the furnace walls in order to protect the air register assembly from furnace heat, particularly when the burner associated with the air register assembly is idle and the secondary air flow is lowered.