Fuel nozzle assembly for reduced exhaust emissions

摘要

A two-stage fuel nozzle assembly (56) for a gas turbine engine. The primary combustion region (120) is centrally positioned and includes a fuel injector (122) that is surrounded by one or more swirl chambers (132, 160) to provide a fuel air mixture that is ignited to define a first stage combustion zone. A secondary combustion region is provided by an annular housing (168) that surrounds the primary combustion region (120) and it includes a secondary fuel injector (126) having a radially-outwardly-directed opening (172) and surrounded by an annular ring (128) that includes openings (194) for providing a swirl chamber for the secondary combustion region (124). Cooling air is directed angularly between the primary and secondary combustion zones to delay intermixing and thereby allow more complete combustion of the respective zones prior to their coalescing further downstream. The primary combustion region (120) is activated during idle and low engine power conditions, and both the primary (120) and secondary (124) combustion regions are activated during high engine power conditions. <IMAGE>