Multi-nozzle fuel injection method for gas turbine

A multi-nozzle fuel injection method for a gas turbine, wherein the gas turbine comprises an axial staged combustor comprising a main combustion section and a secondary combustion section, and the main combustion section is configured to produce mainstream high-temperature flue gas;

• wherein the method comprises the following steps:
• arranging a secondary fuel injection nozzle and a secondary air injection nozzle on the secondary combustion section, wherein the secondary fuel injection nozzle is closer to the main combustion section than the secondary air injection nozzle;
• and
• injecting secondary fuel and secondary primary air in sequence through the secondary fuel injection nozzle and the secondary air injection nozzle, respectively, the secondary fuel being injected into the secondary combustion section before the secondary air thus enabling the secondary fuel to spontaneously combust in a mainstream high-temperature flue gas atmosphere to form a transverse jet flame and increase the flame lift-off height;
• wherein the secondary fuel injection nozzle and the secondary air injection nozzle are perpendicular to a mainstream high-temperature flue gas;
• a distance between the secondary fuel injection nozzle and the secondary air injection nozzle is set to be greater than 2d, and d is the larger of the diameter of the secondary fuel injection nozzle and the diameter of the secondary air injection nozzle.