Gas turbine engine with device for bleeding air from a diffuser

摘要

In a gas turbine engine an auxiliary airflow is provided to power accessories. This auxiliary airflow is obtained from a bleed aperture 7 which is constructed immediately downstream of a diffuser vane 3 in a cusp 6 which is formed in the trailing edge 5 of the vane to provide inertial separation. This high-energy air from the diffuser is used as the primary airflow in an ejector 10 to draw ambient air into the auxiliary airflow to lower the temperature of the bleed air. The ejector is constructed to automatically adjust the amount of ambient air according to the energy of the bleed airflow by means of a piston-actuated spike 13 mounted for sliding movement in the primary nozzle. The spike varies the volume of flow through the primary nozzle according to the pressure exerted by the airflow on the piston.