| 摘要 |
A gas turbine engine (10) of a fan bypass type includes an exhaust shroud (60) having a perforated tubular wall (62) extending between a forward end (64) and an aft end (66). The exhaust shroud is adapted to be affixed to a gas turbine engine exhaust for discharging engine exhaust gases without substantial blockage thereto. The perforations (68) formed in the shroud wall communicate the regions at both sides of the shroud wall to pass fluid flow across the perforated shroud wall so that the mixing of the engine exhaust gases with a surrounding fluid flow is enhanced. The mixing of the engine exhaust gases with the surrounding fluid flow is further enhanced by a trailing edge (70) of the exhaust shroud. The trailing edge is deviated from a straight line in a circumferential direction of the tubular wall to effectively increase the peripheral length of the mixing boundary. Thus, the jet noise contribution volume of the engine exhaust gases is effectively reduced, thereby significantly reducing the aero-engine jet noise. The exhaust shroud for enhancing the mixing of engine exhaust gases with the surrounding fluid flow is applicable to both short and long cowl nacelle gas turbine engines and is simple and economical to manufacture and maintain. |
