Heating medium passing through radiant heating tube - has heat absorbing capacity increasing downstream for uniform heat distribution

摘要

The heating system comprises a tube (1) which distributes radiant heat transferred from a medium passing through this tube, e.g. a mixture of fresh air and combustion gases from one or more burners in a combustion chambers connected to the upstream end (3) of this tube. The heat absorption capacity of at least the effective heat radiating portion of the tube increases in downstream direction. This may be effected by having the cross-sectional flow area through the tube reducing in downstream direction, e.g. reducing from a circular segment (at 3) to an annular segment (2), or by providing transverse baffles in the tube whose surface area increases in downstream direction. Other methods and details of a heating system are specified and illustrated.