Abstract: A flow discharge device, such as a compressor bleed outlet discharging into a bypass duct of a gas turbine engine, comprises an outlet panel 46 which is perforated by openings 48, 50 disposed in an array which tapers in the downstream direction with respect to the flow B in the bypass duct. The configuration of the array of openings 48, 50 creates a plume 60 of tapering form, which enables the bypass flow B to come together downstream of the plume 60 with minimal wake generation, to provide a shield of cooler air so as to avoid contact between the hot gas plume 60 and a wall of 27 of the bypass duct 22. The resulting aerofoil-shaped cross section of the plume 60 also reduces any blocking effect in the bypass duct 22, with consequent performance benefits for the engine fan.

Abstract: A flow discharge device, such as a compressor bleed outlet discharging into a bypass duct of a gas turbine engine, comprises an outlet panel 46 which is perforated by openings 48, 50 disposed in an array which tapers in the downstream direction with respect to the flow B in the bypass duct. The configuration of the array of openings 48, 50 creates a plume 60 of tapering form, which enables the bypass flow B to come together downstream of the plume 60 with minimal wake generation, to provide a shield of cooler air so as to avoid contact between the hot gas plume 60 and a wall of 27 of the bypass duct 22. The resulting aerofoil-shaped cross section of the plume 60 also reduces any blocking effect in the bypass duct 22, with consequent performance benefits for the engine fan.

Abstract: The present invention relates to cooled gas turbine engine aerofoils particularly for turbine stator vanes or tubine rotor blades. The leading edge region of a hollow aerofoil is provided with rows of cooling air passages, which are arranged, in operation, to direct cooling air in the opposite direction to the local flow of the hot gas stream. The cooling air passages are substantially parallel, and have relatively large diameters to reduce the possibility of blockage of the cooling air passages by sand. An air guide tube in the hollow aerofoil is provided with large apertures at its leading edge to minimize the area for sand to adhere to.