Gas turbine engine cooling air flow

摘要

A turbofan engine uses fan air to cool bounding surfaces of the exhaust duct at all times. A portion of the fan air flow is used for augmentor combustion in the augmentation mode. In the non-augmented mode the flow for combustion is stopped and the cooling air is used to cool the tail cone and exit guide vanes. Infrared radiation is thereby reduced when non-augmented.