Abstract: A sensor 10 comprises an array of electrostatic sensor elements 12, each centred at a respective sensing position 14. Each element produces a respective output signal at 16. The outputs 16 can be used to drive respective pixels of a display. This allows an image to be created to represent the electrostatic charge distribution across the region to which the sensor is directed.

Abstract: Blades (20) are friction welded onto a disc (10) to form an integrally bladed rotor. To prevent the formation of defects in the weld interface between the blades (20) and the disc (10) a shielding gas is used. The shielding gas is introduced via two nozzles (22,24). The nozzles (22,24) are circumferentially spaced apart and located on opposite sides of the weld interface. The two gas flows oppose one another to create a curtain of gas, which flows around the weld interface. The gas curtain shields the weld interface from air and so reduces the formation of defects due to oxidation.

Abstract: An arrangement for a gas turbine engine comprises a compressor and its surrounding casing. The casing has a generally cylindrical inner surface, one cylindrical section of the inner casing being provided with a circumferential array of recesses. An axially adjacent cylindrical section of the inner casing surface is provided with an abradable lining. The tips of the rotor blades of the compressor are provided with a treated portion at least partly axially aligned with the recesses in the inner casing, the remaining untreated portion of the rotor blade tips being at least partly axially aligned with the lined section of the inner casing.

Abstract: An electrical machine, such as a generator or motor, is incorporated in a gas turbine engine. The engine has compressor blades which are shrouded at. Beyond the shroud, an electrical machine is provided by rotor projections which run in a channel in flux cores, with which excitor coils are associated. The result is an electrical machine which is external to the combustion gas paths of the engine, for ready access, and can have optimised magnetic flux paths for efficiency. High relative speeds within the electrical machine provide further advantages.

Abstract: A joint assembly for limiting an extension of the joint in the direction of a load path derived from an impact comprising a first member having a portion and a second member having a portion, the portions overlapping one another and arranged generally parallel to one another and secured together via securing means disposed through corresponding holes defined therein. One of the overlapping portions further defines, sequentially in the direction of extension, a shear neck, a pocket and a catcher portion. In the event of a worst-case impact load the securing means shears through the shear neck and the pocket and is arrested by the catcher portion, thereby the extension of the joint assembly is limited and the joint assembly remains integral.

Abstract: A gas turbine engine 10 includes an intermediate pressure compressor 14 connected to an intermediate pressure turbine 22 by a driveshaft 28. The driveshaft 28 comprises a downstream turbine shaft 34 attached to the intermediate pressure turbine 22 and an upstream compressor shaft 32 attached to the intermediate pressure compressor 14. The compressor shaft 32 and turbine shaft 34 are connected together by a splined connection 36 which allows the turbine shaft 34 to drive the compressor shaft 32. If the splined connected 36 should fail, so that it no longer transmits torque, a further splined connection 41 comes into operation to transmit torque between the turbine shaft 34 and compressor shaft 32. When this happens, torque is transmitted via a torsionally weakened, shear section 48 of the turbine shaft 34 which tends to break under certain engine conditions. The turbine shaft 34 is then released axially and turbine overspeed is restrained.

Abstract: A permanent magnet fault tolerant generator 32 is driven by a variable speed shaft 34 to create AC power at terminals 36, converted at 40 to DC power before being applied to a load 38. The converter 40 is a bi-directional device which rectifies AC to DC and also acts as an inverter to synthesize AC from the DC. This synthesized AC waveform is imposed on the terminals 36 to maintain a constant magnitude generator output voltage, regardless of the speed of the shaft 34, and thus regardless of the EMF of the generator. This results in reactive currents flowing between the generator 32 and the converter 40, but allows the generator design have a reduced current rating, resulting in improved generator size and weight.

Abstract: A method of forming a hollow section body by deposition of a weld material includes the steps of providing a welding head 12 and a turntable 36 on which the body is to be formed, supplying a weld material to the welding head 12, the weld material to be deposited on the turntable 36 and connecting the turntable 36 and the welding head 12 to a supply of electricity to form an arc between the welding head 12 and the turntable 36 or the body to melt the material. The method includes the steps of manipulating the turntable 36 and the welding head 12 relative to one another to deposit material to form a first wall 40, manipulating the turntable 36 and the welding head 12 relative to one another to deposit material for form a second wall 42 extending from an angle to the first wall 40 and manipulating the turntable 36 and the welding head 12 relative to one another to deposit material to form a third wall 44 joining the first two walls, to form a hollow section body.

Abstract: A gas turbine engine exhaust nozzle arrangement for the flow of exhaust gases therethrough between an upstream end and a downstream end thereof comprising a nozzle and a plurality of tabs which extend in a generally axial direction from a downstream portion of the nozzle wherein the nozzle further comprises an actuation mechanism capable of moving the tabs between a first deployed position, where the tabs interact with a gas stream to reduce exhaust noise thereof, and a second non-deployed position, where the tabs are substantially aerodynamically unobtrusive.

Abstract: A brush seal for sealing between a rotor and a stator of a gas turbine engine includes a housing and a plurality of flexible bristles held within the housing. The bristles protrude from the housing so that a free end of each bristle is able to contact and seal against a seal surface of the rotor. The brush seal further includes a stop member for limiting movement of the free ends of the bristles towards the seal surface of the rotor, in order to reduce wear on the bristles.

Abstract: A friction vibration damper for damping the vibrations of a vibrating component comprising a body, a chamber and a plurality of elements, the body defines the chamber which is partially filled with the plurality of elements, the friction vibration damper, in use, disposed on or in the vibrating component characterized in that the friction vibration damper is configured to substantially prevent the elements operationally moving in a convection-like flow pattern.

Abstract: A gas turbine engine (10) fan outlet guide vane (34) is manufactured by diffusion bonding titanium alloy sheet metal workpieces (52, 54) together to form an in integral structure (66). A titanium alloy is weld deposited at predetermined positions (70, 72) and in a predetermined shape to build up bosses (42, 44) at the radially outer end (40) of the hollow integral structure (68). The integral structure (66) is inflated at high temperature to form a hollow integral structure (68) of predetermined aerofoil shape. Apertures (46, 48) are drilled through the bosses (42, 44) to enable the radially outer end (40) of the fan outlet guide vane (34) to be attached to a fan casing (32) of the gas turbine engine (10).

Abstract: An electrical machine comprises a combined magnetic gearbox and electrical generator. A first set of permanent magnets (30) are arranged on a rotor (16) to produce a spatially variable first magnetic field. A second set of permanent magnets (32) are arranged on a rotor (40,41,43), stationary pole pieces (36) are positioned between the first set of permanent magnets (30) and the second set of permanent magnets (32) to interfere with the first magnetic field. Rotation of the rotor (16) relative to the pole pieces (36) produces a second magnetic field which rotates the second set of permanent magnets (32). A stator (42) has windings (46) to transduce a changing second magnetic field produced by the rotation of the second set of permanent magnets (32) into an electrical voltage. The electrical machine is useful for a wind turbine generator. Alternatively the arrangement may be modified to produce an electrical motor.

Abstract: A method of manufacturing a fiber reinforced metal disc comprises forming an annular groove in an axial face of a first metallic ring. A plurality of metal coated fibers are arranged in spiral preforms and a plurality of metallic wires are arranged in spiral preforms. The metal coated fiber preforms and the metallic wire preforms are arranged in the groove. An annular projection is formed on an axial face of a second metallic ring. The annular projection on the second metallic ring is aligned with the annular groove in the first metallic ring. Heat and pressure is applied to axially consolidate the metal coated fiber preforms and metallic wire preforms and to bond the first metal ring, the second metal ring, and the preforms to form a unitary composite disc. The use of metal coated fibers and metallic wires allows the mechanical properties to be tailored.

Abstract: A fuel mass flowmeter 10 includes a rotatable drum 22 through which fuel to be metered may pass and an impeller 24 mounted within the drum such that it may rotate relative thereto but is biased against such rotation by a spring 26. The drum 22 may be rotated as fuel is passed therethrough, the passage of the fuel past vanes 36 on the impeller causing the impeller to rotate relative to the drum 22, the extent of rotation depending upon the mass flow rate. The rate of rotation of the drum 22 is measured and a correction factor is applied to the measured mass flow rate, the magnitude of the correction factor depending upon the rate of rotation of the drum 22.

Abstract: This invention relates to a carbon media for storage of hydrogen characterized in that it comprises known and novel micro-domain materials and that it is produced by a one or two-step plasma process. In the one-step plasma process conventional carbon black or graphitic carbon black can be formed. In the two-step plasma process, a hydrocarbon feed material is sent through a plasma zone and becomes partly dehydrogenated in the first step to form polycyclic aromatic hydrocarbons (PAHs), and is then sent through second plasma zone to become completely dehydrogenated to form micro-domain graphitic materials in the second step. By micro-domain graphitic materials we mean fullerenes, carbon nanotubes, open conical carbon structures (also named micro-cones), flat graphitic sheets, or a mixture of two or all of these. The novel carbon material is open carbon micro-cones with total disclination degrees 60° and/or 120°, corresponding to cone angles of respectively 112.9° and/or 83.6°.

Abstract: A gas turbine engine fan blade containment assembly (38) comprising a generally cylindrical, or frustoconical, metal casing (40) has an upstream portion (56), a transition portion (58) and a blade containment portion (54) and a downstream portion (60). The upstream portion (56) has a flange (42) connecting the metal casing (40) to a flange (48) on axially adjacent casing (46). The blade containment portion (54) has a greater thickness (T2) than the thickness (T1) of the upstream portion (54) and the downstream portion (60). The downstream portion (60) has impact protection means (64) located on its inner surface (62) to protect the downstream portion (60) of the containment casing (40). The impact protection means (64) comprises a plurality of radially inwardly and circumferentially extending ribs (80) on the inner surface (62) of the downstream portion (60) to act as spacer between an inner portion of a detached fan blade (34) and the downstream portion (60).

Abstract: An inner rotatable shaft 16 is located within an outer rotatable shaft 18. A stator 52 is provided around the shaft 18. The shaft 18 has a circumferential ring of regions 54a, 54b alternately of relatively high and relatively low magnetic permeability. Flux is therefore transmitted between the stator 52 and the shaft 16 through the regions 54, preferentially through the high permeability regions 54a. Commutation of the stator windings, preferably in synchrony with the speed of rotation of the shaft 18, allows the stator 52 and shaft 16 to interact in the form of an active magnetic bearing. The affect of the presence of the shaft 18 on this interaction is significantly reduced or eliminated.

Abstract: A fan outlet guide vane assembly (36) for a turbofan gas turbine engine (10) comprises a fan casing (32) and a plurality of circumferentially spaced radially extending fan outlet guide vanes (34). The fan outlet guide vanes (34) are secured at their radially outer ends to the fan casing (32). A plurality of panels (40) are secured to the fan casing (32). Each panel (40) is arranged between two adjacent fan outlet guide vanes (34) to define the flow path between the fan outlet guide vanes (34). Each panel (40) comprises a perforated skin (42) and a honeycomb structure (44) to form an acoustic treatment structure. The perforated skin (42) defines the flow path between the fan outlet guide vanes (34). The pressure equalization across the panels (40) minimises the possibility of the panels (40) being removed.

Abstract: A joint (40) for joining a first metal sheet (10) to a second metal sheet (30) comprises a plurality of deformable projections (14) on an edge (12) of the first metal sheet (10). Each deformable projection (14) has an aperture (16) therethrough to form two sides (18,20) and a deformable head (22). The sides (18,20) have dogs (24,26). A plurality of slots (32) are provided through the second metal sheet (30). The deformable projections (14) extend through the slots (32) in the second metal sheet (30). The deformable projections (14) are deformed such that the head (22) of the deformable projection (14) expands the dogs (18,20) of the deformable projections (14) beyond the sides (34,36) of the slots (32) to prevent withdrawal of the deformable projections (14) from the slots (32) in the second ductile sheet (30).