Abstract: A gas turbine engine rotor blade containment assembly (38) comprises a generally cylindrical, or frustoconical, metal casing (40). The metal casing (40) has at least one arched portion (62,64,66) and each arched portion (62,64,66) extends circumferentially around the metal casing (40). Each arched portion (62,64,66) comprises a radially inwardly extending arch (68) in which the trough (74) of the arch (68) is radially inwardly of a straight line (76) interconnecting the axial ends (70,72) of the arch (68). The trough (74) of the arch (68) is radially inwardly of the at least one of the axial ends (70,72) of the at least one arch (68). The arched portions (62,64,66) introduce compressive stresses into the metal casing (40) during a fan blade 34 impact and enable the metal casing (40) to withstand the impact. The fan blade containment assembly (38) is lighter for large diameter turbofan gas turbine engine (10).

Abstract: A fluid flow machine comprises an array of vanes (2) which are supported at their ends by inner and outer support structures 4, 6. The ends of the vanes are received in slots 8, 10, with resilient material 12 disposed between the vane 2 and the wall of the slot 8, 10. A restraint element 14, 34 is mounted in a recess 26, 28; 48 of the support structure 4, 6 and is engaged by a notch 30, 32 in the vane 2 to restrict axial displacement of the vane 2. Consequently, vibration of the vane in directions perpendicular to the lengthwise direction of the vane are damped by the elastomeric material 12 but bodily axial displacement of the vane 2 is prevented by the restraint elements 14, 34.

Abstract: Apparatus for maintaining the temperature of a component of a gas turbine engine below a predetermined maximum working temperature comprises a reservoir for a cooling fluid having a boiling point below the working temperature and in which the component is immersed or with which it is in contact. At least two heat exchangers are associated with the reservoir and operable to effect condensation of vaporised cooling fluid and return of same to the reservoir. Preferably the apparatus is a closed system incorporating three heat exchangers respectively adapted to effect heat exchange with engine fuel, compressed air derived from a fan or low pressure compressor of the engine and ambient air. Means may advantageously be provided to ensure return of condensed cooling fluid to the reservoir when the attitude of the reservoir is altered as a result of aircraft maneuvers.

Abstract: With an active magnetic bearing 1 there is a limit to the available rapidity of response to transient loadings upon a target or rotor 4. Thus, in accordance with the present invention, storage devices 25, 125, 225, 35 hold an electrical voltage VS significantly greater than the normal supply voltage V provided by a normal electrical source 22, 32. In such circumstances when a very large transient loading is detected on the bearing 1 a switch 26, 37 discharges the supply voltage VS across the coil 23, 33 in order that a more rapid increase and higher value inductance current IT is presented to the coil 22, 32 in response to that variable loading upon the target/rotor 24, 34. The electrical discharge from the storage device 25, 125, 225, 35 can be adjusted using the switch 26, 37 or mixing the storage devices 25, 125, 225, 35 as required for an appropriate discharge signal shape.

Abstract: A fan blade (26)comprises a root portion (36) and an aerofoil portion (38). The aerofoil portion (38) has a leading edge (44), a trailing edge (46) and a tip (48) remote from the root portion (36). A concave pressure surface (50) extends from the leading edge (44) to the trailing edge (46) and a convex suction surface (52) extends from the leading edge (44) to the trailing edge (46). A groove (54) is provided in the tip (48) of the aerofoil portion (38)between the leading edge (44) and the trailing edge (46) of the aerofoil portion (38). The groove (54) in the tip (48) of the aerofoil portion (38)is spaced from the leading edge (44) and is spaced from the trailing edge (46). The groove (54) in the tip (48) of the aerofoil portion (38) allows a natural flow of fluid from the concave pressure surface (50) to the convex suction surface (52) of the aerofoil portion (38). This reduces vibrations of the fan blade (26).

Abstract: An electrical power generation assembly comprising a main body having a low density to provide lift and wind driven means on its surface to generate electrical power. The main body has a part-circular, or a part-elliptical, cross section frontal region. The main body has a first distance and a second distance. The ratio of the first distance to the second distance is equal to or more than 0.5 and equal to or less than 5 according to the shape of the frontal region of the main body. The ratio of the diameter of the wind driven means to the first distance is equal to or less than 0.25.

Abstract: A compressor (16) comprises a rotor (40) having a plurality of circumferentially spaced radially outwardly extending rotor blades (42). A casing (44) surrounds the rotor (40) and rotor blades (42). The casing (44) has an inner surface (48) and a plurality of circumferentially spaced slots (50) are provided in the inner surface (48) of the casing (44). Each slot (50) has a length (L), a depth (D), a width (W), an angle (?) of inclination relative to the radial direction, an axial position (AP) relative to the rotor blades (42) and a circumferential position (CP) relative to an adjacent slot (50). The slots (50) are arranged such that at least one of the length (L), depth (D), width (W), angle (?) of inclination relative to the radial direction, axial position (AP) relative to the rotor blades (42) and circumferential position (CP) relative to an adjacent slot (50) varies circumferentially around the casing (44).

Abstract: A fan blade (26) comprises a root portion (36) and an aerofoil portion (38). The aerofoil portion (38) has a leading edge (44), a trailing edge (46) and a tip (48) remote from the root portion (36). A concave pressure surface (50) extends from the leading edge (44) to the trailing edge (46) and a convex suction surface (52) extends from the leading edge (44) to the trailing edge (46). A portion (54) of the tip (48) of the aerofoil portion (38) between the leading edge (44) and the trailing edge (46) of the aerofoil portion (38) is thinner than the remainder (56, 58) of the tip (48). The portion (54) of the tip (48) of the aerofoil portion (38) is spaced from the leading edge (44) and is spaced from the trailing edge (46). The portion (54) of the tip (48) of the aerofoil portion (38) has a recess such that the portion (54) of the tip (48) of the aerofoil portion (38) is thinner than the remainder (56,58) of the tip (48). The recess is arranged on the concave pressure surface (50) of the aerofoil portion (38).

Abstract: A ship propulsion arrangement is provided in which a mechanical drive shaft (3) extends through a hull (9) of a ship (1) to an external body (7). The external body incorporates an electric motor. The mechanical drive shaft (3) is driven when required by either a prime mover (2) located within the ship (1) or by the electric motor in the external body (7). This arrangement provides the benefits of hybrid operation without necessary accommodation of the electric motors within the limited hull space available in a ship (1).

Abstract: A nickel base superalloy comprising 14.0 to 20.0 wt % cobalt, 13.5 to 17.0 wt % chromium, 2.5 to 4.0 wt % aluminium, 3.4 to 5.0 wt % titanium, 0 to 3.0 wt % tantalum, 3.8 to 5.5 wt % molybdenum, 0.035 to 0.07 wt % carbon, 0.01 to 0.04 wt % boron, 0.055 to 0.075 wt % zirconium, 0 to 0.4 wt % hafnium and the balance nickel plus incidental impurities. The nickel base superalloy is suitable for use as gas turbine engine high pressure compressor rotor discs or turbine discs. It is capable of operation at temperatures above 700° C. and has good fatigue crack propagation resistance, creep resistance and tensile strength.

Abstract: A cooling arrangement comprises a support (20) for a plurality of blades (22). The support (20) comprises a plurality of blade mounting members (28) provided between adjacent blades (22). The blades (22) are mounted upon the blade mounting members (28). The cooling arrangement defines a pathway (36) for a cooling fluid. The cooling arrangement further includes a fluid directing formation (40, 44, 44A) to direct the cooling fluid across the blade mounting member (28).

Abstract: A sacrificial liner is provided for an injector access aperture in a combustor casing. The liner has an outer annular surface and an eccentric inner annular surface. The liner serves to protect the combustor outer casing from wear by a series of piston rings mounted in a seal carrier. The eccentricity of the surfaces prevent excess contact pressure between the piston rings and the seal carrier to improve the life of these components.

Abstract: A static structure is provided such as that used as an engine structure 30 within a gas turbine engine. A structure 30 comprises a hub or core 33 with a concentric ring or casing 32. The hub 33 and casing 32 are secured together through spoke or vane elements 31 which are sloped axially and tangentially relative to a principal axis X-X. In such circumstances any roll torque reaction caused by differentially rotating hub and ring motions is retained by the tangential inclination of the spokes or vanes whilst axial sloping of these spokes or vanes 31 and axially sloping of the struts 34 creates bracing in the direction of the principal axis X-X. In such circumstances essentially robust triangles are formed radially and longitudinally respectively each comprising spokes or vanes 31 and struts 34 secured at axially spaced locations on the hub or core 33.

Abstract: By mounting a camera to rotate with a rotating component to be viewed it is possible to review the whole component illuminated by a light source. Generally the component will be specifically marked with target markings to highlight its profile to allow images produced by the camera to be compared for distortion and displacement. Such in situ monitoring arrangements also allow profiling of the surface, and by projection of a grid or matrix onto a component surface any distortion in that matrix is indicative of variations in the surface or through use of astigmatic techniques variations in the incident image pattern can be utilised in order to determine distance variations.

Abstract: A method of simulating life of a rotor blade mounting feature mounted in a complementary rotor disc mounting feature comprises the steps of providing two specimen mounting features (37) each having portions defining pressure faces matching in profile respective faces of the rotor blade mounting feature; providing a fixture (38) having two opposed mounting features (39) each having portions defining pressure faces (78) matching in profile respective faces of the rotor disc mounting feature; mounting the specimen mounting features (37) in the fixture mounting features (39); applying a first load to the specimen mounting features (37); measuring a strain in a region (86) of the fixture (38) between the fixture mounting features (39); applying a second load to the fixture (38), the second load being substantially perpendicular to the first load; and controlling the second load in response to the measured strain. A high cycle load may simultaneously be applied to the specimen mounting features (37).

Abstract: An apparatus (10) for testing attachment features (26,28,30,32) of components (12,14) comprises a first member (16) having a first end (18), a second end (20), a first edge (22) and a second edge (24). The first edge (22) has a first firtree slot (26) to receive a first component (12) and the second edge (24) has a second firtree slot (28) to receive a second component (14). The first component (12) has a firtree attachment feature (30) to fit the first slot (26) and the second component (14) has a firtree attachment feature (32) to fit the second slot (28). The first end (18) of the first member (16) has flanges (34,36) extending laterally and the second end (20) of the first member (16) has flanges (38,40) extending laterally such that the first member (16) is substantially H-shaped in cross-section.

Abstract: In order to more effectively utilise seed crystals 35, 55 to achieve a single crystal grain orientation for a component without the problems of utilising a helix constriction previously necessary to avoid epitaxial grain competition and growth. The present invention creates a wax component pattern 30. This pattern 30 comprises integral sections of wax for a mould component section and for a spacer section with the seed crystal 35 or holder for that crystal therebetween. This pattern 30 is then utilised in order to form a final refractory mould within which the component is formed. By appropriate choice of the spacer section 32, an appropriate spacing between an upper surface of the seed 55 which will be the initial interface with molten castable material to form the component and a chiller surface through which heat is transferred can be determined in order to achieve successful transfer of the seed 55 orientation to the formed component.

Abstract: The present invention provides an actuating apparatus for moving relatively rotatable components. In one embodiment the apparatus comprises: a bearing (30) including first (34) and second (36) relatively rotatable bearing elements for mounting respective first (18) and second (12) rotatable components for relative rotation about a common axis; a pneumatic or hydraulic actuator having a pair of co-acting parts (44, 54), including a first part (54) fixed with respect to the said first rotatable element and a second part (44) fixed with respect to the said second rotatable element; and, means (110) for energising and/or de-energising said actuator means to effect movement of the said co-acting parts and thereby relative rotation of the said first and second bearing elements about the said bearing axis.

Abstract: A rotor system is provided whereby a rotary assembly such as a fan blade combination in a jet engine is brought into rub contact with a casing such that sensors detect vibration. The casing is then retreated in order to open the gap to a desired value for engine performance. In such circumstances, the rub contact position is defined as a base datum reference from which distance the casing is displaced in order to provide the specified gap for engine performance and efficiency.

Abstract: An aircraft engine comprising a nacelle, a first wall and fan outlet guide vanes. The fan outlet guide vanes comprises a plurality of stator vanes extending between a second wall and a third wall. The nacelle having apertures at a region of low pressure. A means to bleed fluid from a region of high pressure at one or more of the first wall, the second wall, the third wall or the stator vanes and at least one duct to connect the means to bleed fluid from the region of high pressure to the at least one aperture in the nacelle. The static pressure at the high pressure region is greater than that in the low pressure region such that at least some of the boundary layer of the fluid flows through the at least one duct to the at least one aperture in the nacelle.