초록 ▼

A premixture of compressed air and gaseous fuel is supplied and conbusted into a head combustion chamber of a combustor for gas turbine and main combustion of lean, low flame temperature is carried out in a rear combustion chamber following the heat combustion chamber to prevent the formation of hig

A premixture of compressed air and gaseous fuel is supplied and conbusted into a head combustion chamber of a combustor for gas turbine and main combustion of lean, low flame temperature is carried out in a rear combustion chamber following the heat combustion chamber to prevent the formation of high flame temperature which tends to promote NOx generation.

대표청구항 ▼

A combustor for a gas turbine comprising a combustion chamber means, means disposed outside of said combustion chamber means for mixing compressed air with a gaseous fuel to form a pre-mixture at a predetermined air excess ratio, means for supplying the pre-mixture into the combustion chamber means

A combustor for a gas turbine comprising a combustion chamber means, means disposed outside of said combustion chamber means for mixing compressed air with a gaseous fuel to form a pre-mixture at a predetermined air excess ratio, means for supplying the pre-mixture into the combustion chamber means from an upstream end thereof to form a pre-mixture flame, means for supplying further gaseous fuel for main combustion together with air at an air excess ratio of 1.3 or more to a region near a tip end of the pre-mixture flame so as to enable a carrying out of a low temperature combustion of a lean mixture, the gaseous fuel to the main combustion chamber being increased in accordance with a gas turbine load, the combustion chamber means includes a head combustion chamber means for pre-mixing combustion to form the pre-mixture flame, a rear combustion chamber means for a main combustion of a lean low temperature flame, a dilution region for cooling combustion gas arranged downstream of an upstream end of the combustion chamber means, an inner cylinder defining a portion of the combustion chamber means with a plurality of louvers for supplying air for the main combustion and dilution, an outer cylinder surrounding the inner cylinder to form a passage for air between the outer cylinder and the inner cylinder of the louvers, an end cover closing one end of the outer cylinder, the means for supplying the pre-mixture includes a supply nozzle for supplying the pre-mixture of gaseous fuels with compressed air, the supply nozzle extending through the end cover and opening into the head combustion chamber means, the means for supplying further gaseous fuel includes a plurality of fuel discharge ports and swirling air ports disposed at the side of the rear combustion chamber means, a plurality of air ports are disposed at the side of the dilution region for enabling a cooling of the combustion gas, the head combustion chamber means has a smaller diameter than the rear combustion chamber means, the fuel discharge ports and swirling air ports are disposed at a junction of the head combustion chamber and the rear combustion chamber means, wherein means are provided for controlling a flow rate of air and a flow rate of fuel to the means for mixing air and gaseous fuel to form the pre-mixture so that a predetermined air excess ratio of said pre-mixture of between 1.2 and 1.4, can be maintained during the start up run and load operation of the gas turbine with the flow rate of the compressed air and the flow rate of the gaseous fuel for forming the pre-mixture being maintained substantially constant during the stationary operation of the gas turbine other than the start-up; and including means for increasing the pressure of the compressed air supplied to the means for mixing as compared to the pressure of the air supplied for main combustion.