| 摘要 |
A noise reduction device 40, for example for use in a bleed assembly 30 of a gas turbine engine, comprises partitions 50, 52 forming cells 54 having apertures 56, 58, 60 which provide contractions and sudden expansions of flow passing through the device. The apertures 56, 58, 60 are disposed relative to each other so as to force the flow to change direction within the cells 54 to break up jets of gas issuing from the apertures 56, 58, 60. Webs 62, 64, 66 may be provided adjacent the apertures 56, 58, 60 to direct flow and to assist in generating turbulence. |
