| 摘要 |
A staged fuel injector 10 has a main fuel circuit 15 for delivering fuel to a main fuel atomizer 25, and a pilot fuel circuit 17 for delivering fuel to a pilot fuel atomizer 35. The pilot fuel atomizer can be located radially inward of the main fuel atomizer, and the pilot fuel circuit is in thermal contact with the main fuel circuit enroute to the pilot fuel atomizer. When fuel is directed through the pilot fuel circuit, fuel within the main fuel circuit is cooled and therefore prevented from coking during low power operation. The main fuel injector can include a prefilmer 24 and an associated swirler 18, with portions of the pilot fuel circuit formed in the outer diametrical surface of the prefilmer as passages 60a, 60b, and associated radial passages 74a, 74b extending through the prefilmer to provide fuel to the pilot atomizer. The main fuel circuit can also be arranged such that portions of the circuit are formed in the outer diametrical surface of the prefilmer as a passage 70, and this passage may be located between pilot fuel circuits 60a and 60b, an so may permit cooling of the main fuel flow by thermal contact with the surrounding pilot flow. |
