LEAN-RICH AXIAL STAGE COMBUSTION IN A CAN-ANNULAR GAS TURBINE ENGINE

摘要

An apparatus and method for lean/rich combustion in a gas turbine engine (10), which includes a combustor (12), a transition (14) and a combustor extender (16) that is positioned between the combustor (12) and the transition (14) to connect the combustor (12) to the transition (14). Openings (18) are formed along an outer surface (20) of the combustor extender (16). The gas turbine (10) also includes a fuel manifold (28) to extend along the outer surface (20) of the combustor extender (16), with fuel nozzles (30) to align with the respective openings (18). A method (200) for axial stage combustion in the gas turbine engine (10) is also presented.

主权项

1. A method for axial stage combustion in a gas turbine engine comprising:
mixing a lean air-fuel mixture in a first stage of combustion of a can-annular combustor of the gas turbine engine, wherein the lean air-fuel mixture has an equivalence ratio of less than one; igniting the lean air-fuel mixture at the first stage of combustion to create hot combustion gas having a first temperature and free radicals; mixing a rich air-fuel mixture with an equivalence ratio of greater than one; injecting the rich air-fuel mixture into the hot combustion gas at a second stage of combustion of the can-annular combustor downstream from the first stage; and igniting the rich air-fuel mixture in the hot combustion gas at the second stage of combustion, such that the first temperature and the free radicals of the hot combustion gas promote combustion of the rich air-fuel mixture within a predetermined hydrocarbon emissions limit, and the first temperature of the hot combustion gas increases to a second temperature.