BLOWING METHOD FOR SECONDARY AIR IN SECONDARY COMBUSTION CHAMBER

摘要

PROBLEM TO BE SOLVED: To effectively burn unburned substances even when throttling secondary air supply amount.;SOLUTION: The flow speed of the secondary air is operated in two systems from an upper stage nozzle and a lower stage nozzle arranged on a front wall and a partition wall opposing to each other in a secondary combustion chamber to form vertical two stages in the upstream and downstream direction. This blowing method is provided with a process A of increasing/reducing the secondary air supply amount by changing the flow speed of the secondary air in the lower stage nozzle between a low flow speed region and a high flow speed region and changing the flow speed of the secondary air in the upper stage nozzle at a predetermined ratio between a minimum flow speed region and the low flow speed region, in a low heat quantity region; a process B of increasing/reducing the secondary air supply amount by maintaining the flow speed of the secondary air in the lower stage nozzle at an approximately constant level in the high flow speed region and changing the flow speed of the secondary air in the upper stage nozzle between the low flow speed region and the high flow speed region in an intermediate heat quantity region so that the flow speeds of the upper and lower stage nozzles are the same in a high region limit in the intermediate heat quantity region; and a process C of increasing/reducing the secondary air supply amount by changing the flow speeds of the secondary air in the upper and lower stage nozzles at the same ratio.;COPYRIGHT: (C)2010,JPO&INPIT