Staged, mixed combustor assembly having low emissions
AssigneeGeneral Electric Company
InventorsJohn J. Ciokajlo, Willard J. Dodds
Life of this patent
Estimating the term…
Abstract
A combustion assembly includes a combustor having inner and outer pilot liners, each being in the form of a lobed mixer having outer and inner cold and hot chutes. A plurality of carburetors are joined to a dome disposed at upstream ends of the liners for providing a pilot fuel/air mixture for generating pilot combustion gases in the hot chutes. A plurality of fuel spraybars are disposed downstream from the carburetors and are aligned radially with the cold chutes for selectively injecting main fuel into main airflow for generating a main fuel/air mixture ignitable by the pilot combustion gases. In a preferred and exemplary embodiment of the invention, lean combustion gases are obtained for reducing NO.sub.x emissions in a relatively short residence time.
Claims28
A combustion assembly for receiving compressed airflow from a compressor in a gas turbine engine, said assembly including a combustor comprising:
- an outer pilot liner having an upstream end and a downstream end and including a serpentine circumference having spaced peaks and valleys;
- an inner pilot liner having an upstream end and a downstream end and including a serpentine circumference having peaks and valleys, said inner pilot liner being spaced from said outer pilot liner to define a pilot combustion zone;
- said outer and inner pilot liner downstream ends defining a mixer outlet wherein said outlet pilot liner valleys are radially aligned with an disposed adjacent to respective ones of said inner pilot liner peaks;
- an annular dome joining together said inner and outer pilot liner upstream ends;
- a plurality of carburetors joined to said dome and circumferentially spaced from each other for providing a pilot fuel/air mixture into said pilot combustion zone for generating pilot combustion gases;
- each of said outer and inner pilot liners being in the form of a lobed mixer having outer and inner cold chutes, respectively, in flow communication with a main airflow portion of said compressed airflow, and outer and inner hot chutes, respectively, defining said pilot combustion zone for channeling said pilot combustion gases;
- a plurality of circumferentially spaced fuel spraybars disposed downstream from said carburetors, each aligned radially with said cold chutes for selectively injecting main fuel into said main airflow for providing a main fuel/air mixture ignitable by said pilot combustion gases for generating main combustion gases, said main fuel/air mixture being mixable with said pilot combustion gases downstream of said mixer outlet for forming mixed combustion gases;
- fuel control means for controlling pilot fuel channeled through said carburetors and said main fuel channeled through said fuel spraybars, said fuel control means being effective for channeling said main fuel to said fuel spraybars for generating a lean main fuel/air mixture;
- and
- a turbine nozzle having:
- a plurality of nozzle vanes extending radially between outer and inner bands, and being circumferentially spaced apart to define nozzle flow channels;
- an annular inlet defined at leading edges of said vanes and disposed in flow communication with said pilot and main combustion gases;
- an annular outlet defined at trailing edges of said vanes;
- and
- said flow channels being converging in a downstream direction for quenching said pilot and main combustion gases channeled therethrough.
Dependencies are inferred from the claim text.