Abstract: A gas turbine engine duct turns radially inwardly in the downstream direction. The duct includes a plurality of radially extending stator vanes. A generally circumferentially extending splitter vane is provided between two circumferentially neighbouring stator vanes. The splitter vane improves the flow near to the radially inner wall of the duct. This can allow greater design freedom in the duct geometry.

Abstract: An aerofoil for a compressor comprising a suction surface and a pressure surface with a thickness distribution defined therebetween, the aerofoil further comprising a first local maximum in the thickness distribution and a second local maximum in the thickness distribution, the second local maximum being downstream of the first local maximum and the second local maxima being formed by a first region of concave curvature in the suction surface between the first and second local maxima, wherein the second local maximum is disposed such that in use a boundary layer upstream of the second local maximum on the suction surface is thinned by the second local maximum, and in addition the boundary layer may be sufficiently thinned so that an interaction of an upstream flow feature with the thinned boundary layer is capable of generating a turbulent spot with a calmed region downstream of the turbulent spot.

Abstract: A rotor blade for a gas turbine engine, comprising an aerofoil having pressure and suction surfaces, leading and trailing edges, and an array of passages at a tip region of the aerofoil. The passages extend from the pressure surface to the suction surface of the aerofoil and are disposed so that the array creates, in operation, a planar jet of gas issuing from the suction surface. The jet is inclined outwardly from the suction surface and towards the tip, and in the direction from the leading edge to the trailing edge. The jet inhibits migration away from the suction surface of a clearance vortex formed by leakage of air over the tip of the rotor blade.

Abstract: A rotor blade for a gas turbine engine, comprising an aerofoil having pressure and suction surfaces, leading and trailing edges, and an array of passages at a tip region of the aerofoil. The passages extend from the pressure surface to the suction surface of the aerofoil and are disposed so that the array creates, in operation, a planar jet of gas issuing from the suction surface. The jet is inclined outwardly from the suction surface and towards the tip, and in the direction from the leading edge to the trailing edge. The jet inhibits migration away from the suction surface of a clearance vortex formed by leakage of air over the tip of the rotor blade.

Abstract: An aerofoil (52) for a compressor comprising a suction surface (56) and a pressure surface (58) with a thickness distribution defined therebetween, the aerofoil further comprising a first local maximum in the thickness distribution and a second local maximum (54) in the thickness distribution, the second local maximum (54) being downstream of the first local maximum and the second local maxima being formed by a first region of concave curvature in the suction surface between the first and second local maxima, wherein the second local maximum is disposed such that in use a boundary layer upstream of the second local maximum on the suction surface is thinned by the second local maximum, and in addition the boundary layer may be sufficiently thinned so that an interaction of an upstream flow feature with the thinned boundary layer is capable of generating a turbulent spot with a calmed region downstream of the turbulent spot.

Abstract: A gas turbine engine turbine comprises an annular array of nozzle guide vanes and an annular array of turbine blades mounted within its annular casing. An array of radially extending protrusions are positioned axially upstream of said array of said nozzle guide vanes and protruding inwardly from the inner casing wall so as to mix the tangential momentum component of the overtip leakage fluid flow before it reaches the array of nozzle guide vanes.

Abstract: A rotor blade tip arrangement is provided in which winglets extend from the end of rotor blade aerofoil walls. These winglets incorporate passages which extend to coolant apertures or holes in order to present a coolant flow about the tip of the turbine rotor blade. The winglets define at least an open ended gutter channel in order to inhibit leakage flow across the tip arrangement from a pressure side P to a suction side S. The coolant flow facilitates cooling of the arrangement despite any heating caused by leakage flow across the arrangement.

Abstract: A turbine engine arrangement is provided in which contra rotating shafts 104, 105 are respectively secured to a fan and a gearbox 106 which is also coupled to the shaft 104. In such circumstances the relative rotational speed ratio between the shafts 104, 105 can be determined with a first low pressure turbine 101 secured to the first shaft 104 arranged to rotate at a lower speed but provide high work whilst a second low pressure turbine 102 secured to the second shaft 105 rotates at a higher speed governed by the gearbox 106. By such an arrangement a smaller gearbox 106 may be used as less power is transferred through that gearbox 106 than with previous arrangements. By contra rotation of the turbines 101, 102 a lower flow deflection guide vane assembly 103 may be used and a further stator/guide vane assembly is not required between the turbines 101, 102.

Abstract: A turbine component such as a turbine blade has a cooling chamber that is tapered. The taper induces and maintains a helical swirl that improves the cooling efficiency of the cooling process and enables the turbine component to operate at higher temperatures.

Abstract: A transition duct for a gas turbine engine typically contains one or more non-turning fairings. These fairings disturb the air flow through the duct, leading to flow separation and aerodynamic inefficiency. The invention proposes non-axisymmetric perturbations in the duct end walls to minimise these undesirable aerodynamic effects. This permits the construction of shorter and lighter transition ducts, with more pronounced curvature.

Abstract: An axial compressor has at least one circumferential row of aerofoil members (30a, 30b, 30c) in which at least one of the two end walls (37) between adjacent blades is given a non-axisymmetric profile, defined by circumferentially-extending sinusoids at a number of axial positions (AA, BB, CC). Corresponding points on the successive sinusoids are joined by spline curves, so that the curvature of the end wall is smooth. This end-wall profiling modifies the boundary layer flow at the wall, reducing or eliminating the corner separation and reversed flow associated with known arrangements.

Abstract: A turbine component, such as a turbine blade 1, 21, has a coolant supply passage 4, 24 and a cooling chamber 3, 23 connected by an injection passage 5, 25. The cooling chamber 3, 23 includes flow guides in the form of vanes 7, 8 or grooves 37 which act to create a coolant flow in a spiral direction. Thus, there is limited coolant flow impingement and greater cooling effect to allow the turbine component to operate at higher temperatures.

Abstract: A turbine component, such as a turbine blade 1, 21, has a coolant supply passage 4, 24 and a cooling chamber 3, 23 connected by an injection passage 5, 25. The cooling chamber 3, 23 includes flow guides in the form of vanes 7, 8 or grooves 37 which act to create a coolant flow in a spiral direction. Thus, there is limited coolant flow impingement and greater cooling effect to allow the turbine component to operate at higher temperatures.

Abstract: An aerofoil (39) for a gas turbine engine (10) includes one or more internal cooling passage (74,76) for receiving a flow of cooling fluid, and means (84,86,88,90) for inducing at least two vortices in cooling fluid flowing through each cooling passage. Fluid within the vortices has a radially outwards, screw-type motion. The two vortices produce effective cooling of the aerofoil, which may be an aerofoil of a turbine blade.

Abstract: An aerofoil (34) for a gas turbine engine is substantially solid, including a concave pressure surface (42) and a convex suction surface (40). The pressure surface (42) is provided with a projection in the form of an elongate fin (44) which extends in the radial direction of the aerofoil.

Abstract: An aerofoil (34) for a gas turbine engine is substantially solid, including a concave pressure surface (42) and a convex suction surface (40). The pressure surface (42) is provided with a projection in the form of an elongate fin (44) which extends in the radial direction of the aerofoil.

Abstract: An aerofoil (22,24), preferably of a high lift, highly loaded design, for an axial flow turbo machine (10). The aerofoil having a span, a leading edge (LE), a trailing edge (TE) and a cambered sectional profile comprising a pressure surface (30,72) and a suction surface (28,70) extending between the leading edge (LE) and trailing edge (TE). The aerofoil (22,24) having at least one aerofoil cross bleed passage (36,37,78,80) defined in the aerofoil (22,24) which extends from the pressure surface (30,72) through the aerofoil (22,24) to the suction surface (28,70). The at least one passage (36,37,78,80) preferably disposed generally at a location on the suction surface (28,70) at which boundary layer separation from the suction surface (28,70) would normally occur.

Abstract: An aerofoil (39) for a gas turbine engine (10) includes one or more internal cooling passage (74, 76) for receiving a flow of cooling fluid, and means (84, 86, 88, 90) for inducing at least two vortices in cooling fluid flowing through each cooling passage. Fluid within the vortices has a radially outwards, screw-type motion. The two vortices produce effective cooling of the aerofoil, which may be an aerofoil of a turbine blade.

Abstract: To reduce profile losses in the aerofoils of low pressure turbines of axial flow reaction turbines, the wake-passing effects on a row of aerofoils downstream of a first row of aerofoils are enhanced by providing a region of roughness on part of the suction surface of each aerofoil of the downstream row. The region of roughness has its leading edge between the location of the geometric throat on the suction surface and a location 75% of the surface perimeter from the leading edge. The region extends over at least 3% of the suction surface perimeter. The use of such a region of roughness is particularly effective in improving the performance of very high-lift aerofoils (coefficient of lift of 1.1 or greater).

Abstract: An aerofoil (22,24), preferably of a high lift, highly loaded design, for an axial flow turbo machine (10). The aerofoil having a span, a leading edge (LE), a trailing edge (TE) and a cambered sectional profile comprising a pressure surface (30,72) and a suction surface (28,70) extending between the leading edge (LE) and trailing edge (TE). The aerofoil (22,24) having at least one aerofoil cross bleed passage (36,37,78,80) defined in the aerofoil (22,24) which extends from the pressure surface (30,72) through the aerofoil (22,24) to the suction surface (28,70). The at least one passage (36,37,78,80) preferably disposed generally at a location on the suction surface (28,70) at which boundary layer separation from the suction surface (28,70) would normally occur.