Gas Turbine Combustor and Method for Operating Same

A method for operating a gas turbine combustor which includes:

• a combustion chamber for burning a fuel and air in a mixed condition;
• and
• a burner provided upstream in a gas flow direction of the combustor, for supplying the fuel and the air to inside of the combustion chamber and thus stabilizing a flame, the burner including a first swirler in which both of a plurality of gas injection holes for injecting the fuel, and a plurality of air injection holes for injecting air are arranged at alternate positions in a circumferential direction of the swirler, and a second swirler provided at an outer periphery of the first swirler, the second swirler being fitted only with a plurality of gas injection holes to inject the fuel;
• wherein:
• after the fuel injected from the first swirler has been controlled in flow rate so that the flow rate of the fuel and that of air injected from the first swirler approach a predetermined stoichiometric mixing ratio, the fuel and the air are burnt to form an inner flame and then the fuel injected from the second swirler is burnt by utilizing heat of the inner flame to form an outer flame.