摘要 |
#CMT# #/CMT# The engine has a nozzle with a diffuser (26) connected in downstream of a centrifugal compressor driving turbine and a power turbine (20). A jet pump (30) has an upstream part surrounding a downstream end of the diffuser by arranging the end with an annular gap (32) for a secondary air flow to cool an engine compartment. The jet pump has a wall formed partially by a sound attenuator (34) e.g. Helmholtz resonator, to attenuate sound frequency generated by rotation of the turbines and an annular combustion chamber, where the attenuator is made of titanium based metallic material. #CMT#USE : #/CMT# Gas turbine helicopter engine. #CMT#ADVANTAGE : #/CMT# The jet pump has the wall formed partially by the sound attenuator to attenuate the sound frequency generated by the rotation of the centrifugal compressor driving turbine, the power turbine and the combustion chamber, thus allowing an effective noise reduction in the helicopter while protecting the wall from gases from the turbine. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a partial view of an assembly of a diffuser and a jet pump of a gas turbine helicopter engine. 20 : Power turbine 26 : Diffuser 30 : Jet pump 32 : Annular gap 34 : Sound attenuator. |