Patent ID: 7607308
Filing Date: 2009-10-27
Classification: F02C,F02K,F28D,F28F

Abstract:
1. A turbofan engine comprising: a fan powered by a core engine including a multistage compressor therein, and a fan bypass duct surrounding said core engine; a bleed system including a primary bleed circuit for bleeding pressurized air from said compressor joined in flow communication with a heat exchanger, and a secondary bleed circuit for bleeding fan air from said fan bypass duct joined in flow communication with said heat exchanger; and said secondary bleed circuit includes a bleed conduit having a duct inlet facing forwardly inside said bypass duct, and duct outlet joined by a valve to said heat exchanger, and an acoustic suppression shroud extending forwardly from said duct inlet inside said bypass duct with a side opening at said duct inlet for suppressing pressure oscillations inside said bleed conduit when said valve is closed.