Motor de helicóptero de turbina de gas de emisión sonora reducida por tratamiento acústico de un eyector

摘要

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.