Gas turbine combustor, gas turbine, and combustion method for oil fuel

A gas turbine combustor, comprising:

• a first burner with a plurality of first nozzles disposed along an inner circumference of a cylindrical combustion tube;
• and
• a second nozzle surrounded by the plurality of first nozzles,
• wherein the second nozzle
• has a fuel injection hole capable of injecting fuel, and
• is capable of injecting the fuel injected from the fuel injection hole such that a spray shape of the fuel has a longest first major axis passing through a first centroid which is a centroid of the spray shape, and a first minor axis passing through the first centroid, as well as being orthogonal to the first major axis and shorter than the first major axis, in a cross-section orthogonal to a central axis of the combustion tube.

A combustion method for oil fuel in a gas turbine, comprising:

• a step of injecting the oil fuel from a plurality of first nozzles disposed along an inner circumference of a cylindrical combustion tube in a first burner with the plurality of first nozzles;
• and
• a step of injecting the oil fuel from a fuel injection hole of a second nozzle surrounded by the plurality of first nozzles,
• wherein the step of injecting the oil fuel from the fuel injection hole includes injecting the oil fuel injected from the fuel injection hole such that a spray shape of the oil fuel has a longest major axis passing through a centroid of the spray shape, and a minor axis passing through the centroid, as well as being orthogonal to the major axis and shorter than the major axis, in a cross-section orthogonal to a central axis of the combustion tube.