PRESSURIZED NACELLE COMPARTMENT FOR ACTIVE CLEARANCE CONTROLLED GAS TURBINE ENGINES

摘要

The thrust specific fuel consumption (TSFC) of a gas turbine engine employing an exterior active clearance control system is improved by operating with the pressure within the nacelle compartment 46 to which active clearance control air 20 is discharged, under altitude cruise conditions, at a level on the order of one to two and one-half pounds per square inch (1-21 DIVIDED 2 psi) above the ambient atmosphere, low discharging from the nacelle compartment being directed through an aft facing vent nozzle 58 for purposes of thrust recovery.