Gas turbine combustor

A diffusion combustor comprising:

• a first fuel nozzle, being tubular, having an inlet end and an outlet end, and arranged at an axial portion of the combustor;
• a first air supply pipe, disposed coaxially with and at an outer periphery of said first fuel nozzle, having a first swirler at an inlet end thereof and a discharge end thereof positioned in the vicinity of the outlet end of said first fuel nozzle;
• a second tubular air supply pipe disposed coaxially with said first fuel nozzle and at an outer periphery of said first air supply pipe, and having an annular second swirler in the vicinity of the discharge end of said first air supply pipe, said second swirler having a same swirling direction as that of said first swirler;
• a combustion chamber at the downstream side of the outlet end of said second air flow pipe;
• a plurality of first fuel injection ports at the discharge end of said first fuel nozzle;
• and
• a plurality of second fuel injection ports in the side face of the said first fuel nozzle between said first swirler of said first air supply pipe and the discharge end thereof.

A gas turbine combustor comprising:

• a diffusion combustor, arranged at an axis portion of a combustion chamber, for injecting fuel and effecting diffusion combustion;
• a plurality of air supply means provided for said diffusion combustor in the vicinity of a fuel outlet of said diffusion combustor for supplying air in the vicinity of the fuel outlet of said diffusion combustor;
• and
• a premixing combustor arranged at an outer periphery of said diffusion combustor for injecting fuel/air mixture and effecting premixed combustion;
• wherein fuel supply means is provided for supplying fuel to said air supply means and pre-mixture of air and fuel is supplied for combustion of fuel from said fuel outlet of said diffusion combustor from each of said air supply means.

A gas turbine combustor comprising:

• a diffusion combustor provided at an axis portion of the gas turbine combustor for injecting fuel and effecting diffusion combustion in a combustion chamber;
• a plurality of first premixing combustors arranged at the outer periphery of said diffusion combustor for injecting a mixture of air and fuel and effecting premixed combustion;
• a plurality of second premixing combustors formed so that mixture outlet ends thereof project more downstream than those of said first premixing combustors;
• a mixture injection nozzle for supplying mixture of air and fuel into said combustion chamber in the vicinity of a fuel outlet end of said diffusion combustor provided between said diffusion combustor and said first and second premixing combustors;
• wherein said first and second premixing combustors are alternately arranged in a periphery direction at the outer periphery side of said diffusion combustor;
• wherein, swirlers are provided in the vicinity of the mixture outlet ends of said first premixing combustors for imparting swirling motion to the mixture;
• wherein fuel is injected from said mixture injection nozzles, said first premixing combustors, and said second premixing combustors in the mentioned order so as to increase a flow rate of the mixture as a gas turbine load increases.

A gas turbine combustor comprising:

• a diffusion combustor, arranged at an axis portion of a combustion chamber, for injecting fuel and effecting diffusion combustion;
• a premixing combustor arranged at an outer periphery of said diffusion combustor for injecting fuel/air mixture and effecting premixed combustion;
• wherein said diffusion combustor comprises:
• a cylindrical liner extending along the axis of said diffusion combustor;
• a tubular diffusion fuel nozzle, disposed at the axis of said cylindrical liner and having a diffusion fuel outlet at a downstream side thereof within said cylindrical liner;
• an air chamber, defined by said tubular diffusion fuel nozzle and said cylindrical liner, having an air outlet at a downstream side thereof and in the vicinity of said diffusion fuel outlet for supplying air in the vicinity of the diffusion fuel outlet of said diffusion combustor;
• and
• a fuel inlet provided at an upstream side of said air chamber for supplying fuel into said air chamber to premix the fuel with air in said air chamber, whereby fuel air pre-mixture is supplied from said air outlet of said air chamber for combustion of diffusion fuel from said tubular diffusion fuel nozzle.