Abstract: Embedding electrical machines in gas turbine engines has particular advantages by avoiding the need to provide mechanical connections. However, electrical machines such as switched reluctance electrical machines require relatively large electrical capacitors to accommodate and filter voltage variations in the phases of the electrical machine. Generally, the electrical machine will have a motoring period or generating period with a spacer period between. By injecting electrical current as electrical power in the spacer period, there is limited effect upon net torque within the electrical machine or electrical power generation. However, such stored electrical power in an inductive winding element of the electrical machine augments power pulses provided by a power source incorporating an electrical capacitor. In such circumstances, a smaller sized electrical capacitor can be used.

Abstract: A securing arrangement 32 for securing an actuating lever 20 to a spindle 14, for example a spindle 14 of a variable inlet guide vane 10 in a gas turbine engine, comprises a fastening formation 38 rotatably co-operable, in use, with a corresponding fastening formation 30 on the spindle 14. The securing arrangement 32 is rotatable relative to the spindle 14 to a securing position in which the respective fastening formations 30, 38 co-operate so that the securing arrangement 32 secures the actuating lever 20 to the spindle 14. The securing arrangement 32 includes anti-rotation means 42, preferably in the form of anti-rotation tabs 44, for preventing rotation of the securing arrangement 32 from the securing position.

Abstract: A temperature indicating paint comprises 4 wt % to 40 wt % sodium alumino sulpho silicate, 1 wt % to 38 wt % nickel antimony titanate and the binder comprises 25 wt % to 50 wt % silicone resin 10 wt % to 30 wt % acrylic resin each excluding solvent. This composition undergoes colour changes occur, these are; Blue 520-560° C.; Light Blue 950-990° C.; Light Yellow 1000-1040° C.; Glazed Black 1160-1200° C. The colour changes are particularly distinct and enable accurate analysis particularly, but not exclusively, in gas turbine engines.

Abstract: Operation of gas turbine engines and in particular gas turbine engines utilised for aircraft, in an efficient manner is a desired objective. Thus engine efficiency is typically determined through use of an engine performance parameter. One such engine performance parameter is with regard to specific fuel consumption. However, such parameters may vary as a result of inherent deterioration with regard to the engine. By utilising a computational model to determine variations in the performance parameter such as the specific fuel consumption changes as a result of such inherent engine degradation can be accommodate. Thus, such degradation may not swamp actual changes in fuel consumption or the engine performance parameter which are indicative of changes of engine efficiency.

Abstract: A control mechanism is provided for moving at least two components of a gas turbine engine. The control mechanism comprises a moveable actuation rod. The control mechanism further comprises a first linkage arrangement which includes a first bell crank and which operatively connects the actuation rod to a first component of the gas turbine engine. Movement of the actuation rod produces an output motion of the first bell crank which in turn drives movement of the first component. The control mechanism further comprises a second linkage arrangement which includes a second bell crank and which operatively connects the actuation rod to a second component of the gas turbine engine. Movement of the actuation rod produces an output motion of the second bell crank which in turn drives movement of the second component.

Abstract: The seal arrangement (154) is arranged between the casing portions (50,52) and a fluoropolymer O-ring seal (72) is positioned between the casing portions (50,52). A first protecting member (156) is positioned between the fluoropolymer O-ring seal (72) and the casing portion (50) and the first protecting member (156) consists of a polymer and hydroxyapatite. The first protecting member (156) consists of 50 to 80 wt % polymer and 20 to 50 wt % hydroxyapatite and incidental impurities. The first protecting member (156) is located in an annular groove (70) and is thus arranged between the casing portion (50) and the fluoropolymer O-ring seal (72). The first protecting member (156) is substantially U-shaped in cross-section and the fluoropolymer O-ring seal (72) is positioned between the legs of the U-shaped cross-section first protecting member (156). The first protecting member (156) prevents corrosion of the casing portion (50) by the fluoropolymer O-ring seal (72).

Abstract: A flow modulating device comprises flow modulating elements 8 of a shape memory alloy, which are acted upon by resilient elements 10. The flow modulating elements 8 and resilient elements 10 are mounted on a common support ring 6. At one temperature, the flow modulating elements 8 overcome the resilient force of the resilient elements 10 to lie against the wall of a duct 4 in which the device is situated. The flow modulating elements 8 thus offer a relatively low resistance to flow in the duct 4. At a second temperature, the force of the resilient elements 10 overcomes that of the flow modulating elements 8 to deflect them inwardly of the duct 4, so increasing the flow resistance of the device.

Abstract: Fibre substrates act as a conduit for light along which response signals are transmitted to a controller in the form of an electronic device associated with a component. The processed signals are stored in a local memory to provide a component history and a prediction of future performance and life. Service and repair history may be added to the component device memory to enable a complete history to be stored with the component. A controller may transmit data to an external controller or display through typically a wireless connection. Power to the component electronics may be provided by an induction loop or transformer.

Abstract: A variable reluctance electric machine comprising a rotor and a stator; the stator having two or more electromagnetic windings and the rotor having a plurality of salient poles, the salient poles defining axially extending cooling fluid channels; wherein the salient poles and the cooling fluid channels are circumferentially skewed along at least a part of their length whereby in use the cooling fluid channels impel cooling fluid in a substantially axial direction towards the electromagnetic windings and the stator to facilitate heat transfer and dissipation from the windings.

Abstract: A turbine engine arrangement incorporates an electrical machine combination which can act as a generator or motor. Thus, the combination during initial turbine engine arrangement start-up acts through this motor to drive shaft rotation. This shaft rotation creates core compressed air which is bled through a valve to an air turbine such that the electrical machine when acting as a motor or generator at low engine loads is appropriately cooled. The arrangement also includes a compressor fan which generates an airflow utilised by the air turbine in order to drive the electrical machine as a generator of electrical power when engine conditions dictate. A duct is provided to direct airflow exhausted from the air turbine to a heat exchanger arranged to exchange heat with a bypass flow from the compressor fan.

Abstract: Utilisation of electrostatic sensor elements in an array to provide an electrostatic image is known. Problems can arise with respect to cross talk between electrostatic sensor elements and as a result of external electrical sources. By providing a differential input amplifier and taking output signals from adjacent or adjoining sensor elements to providing a differential signal it is possible to improve images. Furthermore, the differential input amplifier incorporates decoupling devices such as capacitors to reduce noise within the output and input signals and the aspect ratio of the sensor in terms of depth to width can also aid reduction in noise levels.

Abstract: A method of manufacturing an aerofoil structure to have a portion with an increased erosion resistance, the method comprising: providing one or more titanium elements (2, 4, 6) and a beta-stabilizing material (8); wherein the one or more elements (2, 4, 6) have an alpha-beta microstructure; assembling the one or more elements (2, 4, 6) and the beta-stabilizing material (8) such that the beta-stabilizing material (8) is adjacent to the one or more elements (2, 4, 6); and heating the assembly such that the beta-stabilizing material (8) diffuses into an adjacent portion of the one or more elements (2, 4, 6), causing the adjacent portion of the one or more elements (2, 4, 6) to have a beta microstructure which provides an increased erosion resistance.

Abstract: Provision of appropriate fixtures for locating components for fabrication, machining and installation purposes is important. Traditionally, solid fixtures have been utilised but these have limitations with regard to consistency of orientation particularly if the fixture is removed from a base support or workbench regularly. By providing sheet elements for sides 2, 3 and spacers 4, 5 a robust structure can be achieved when these sheet elements are secured at corners to a base support 8 and to each other at top portions. In such circumstances the fixture 1 can present location plates 41, 42 upon a locator 43. The locator 43 comprises cross secured plates which extend through at least one cross hole to limit movement of the locator upon which the location plates 41, 42 are presented to axial displacement. Rigidity of the fixture is further reinforced by integrating its structure with its base-plate support.

Abstract: A method of analysing a welding parameter associated with a linear friction welding process. The linear friction welding process incorporates a weld cycle comprising a burn-off phase, the end of the burn- off phase being determined during the weld cycle by reference to a respective weld upset target. The method comprises: recording a profile of the weld parameter as a function of time during the weld cycle and assessing the recorded profile against a predetermined, respective threshold profile for the weld parameter which is based on a pre-estimate of the end of the burn-off phase. The assessment is carried out retrospectively following a determination of the actual end of the burn-off phase for the recorded profile, and comprises time-shifting the threshold profile relative to the recorded profile so that the pre-estimated endpoint of the burn-off phase is closer to, and preferably coincidental with, the actual endpoint of the burn off phase.

Abstract: Provisions of shields for protecting welds as well as providing heat treatments are advantageous. Previously such shields were bespoke constructions produced iteratively and empirically for particular applications and uses. By utilisation of accurately cut sheets of material within which labyrinths are created it is possible to produce an output flow which is even and incorporates no vortexes. In such circumstances problems with regard to edge entrainment of oxygen causing possible oxidation problems in output flows as well as variations in heat treatments can be avoided. The shield also avoids use of welds which may become distorted during welding or heat treating processes. For reproducibility the shield is formed from accurately produced reproducibility components such that shields can be made at a number of sites to provide the same shield function.

Abstract: A method of manufacturing a component (10) comprising a first layer (12), a second layer (14) and an internal structure (16) therebetween, wherein the method comprises: providing the internal structure (16) with a first bridging portion (18) and a second bridging portion (20) with a gap (22) therebetween; bonding each bridging portion (18, 20) to the first layer (12) at first and second ends of each bridging portion; providing an interlocking portion (24) and disposing the interlocking portion (24) such that: a central portion (26) of the interlocking portion (24) is in the gap (22) between the first and second bridging portions (18, 20); a first end (28) of the interlocking portion is between the first bridging portion (18) and the first layer (12); and a second end (30) of the interlocking portion is between the second bridging portion (20) and the first layer (12); bonding the central portion (26) of the interlocking portion to the second layer (14); expanding the component (10) so that the first and secon

Abstract: A method of monitoring the health of a gas turbine engine 10 comprising a fuel system 30 having a fuel metering valve 36 and a fuel pump 40 for supplying fuel to a combustor apparatus 15. The method comprising the steps of: monitoring the fuel metering valve percentage open, detecting and sending a warning message when the fuel metering valve percentage open is at 97% or greater and within a predetermined time from when the first percentage open is at 97% or greater, replacing the fuel pump 40. In this way scheduling of servicing and replacement of the fuel pump may be made without disruption to the aircraft operator particularly where the operator has a fleet of aircraft.

Abstract: An aerofoil made from a sheet metal blank which is bent in the shape of an aerofoil such that it has a leading edge, a trailing edge, a pressure side and a suction side, and the blank is joined at the trailing edge. The regions of the sheet metal blank that form the leading edge, trailing edge and pressure side of the aerofoil comprise a plurality of perforations. The suction side region of the sheet metal blank is imperforate.

Abstract: A temperature measuring arrangement measures the temperature of a fluid passing a component. The arrangement includes a temperature measuring device having a substrate of low thermal capacity that has applied thereto two or more temperature recording media. The device is attached to and spaced apart from the component and is in the fluid flow.

Abstract: A clearance control apparatus for controlling the clearance between a rotary assembly (17) and a casing (24) surrounding the rotary assembly (17) is disclosed. The clearance control apparatus comprises a temperature measuring device (34) to measure the temperature of a radially outer portion of the rotary assembly and a cooling arrangement (28) to cool the casing (24). A control system (36) is associated with the temperature measuring device (34) and the cooling arrangement (28) to control the extent of cooling of the casing (24). The extent of cooling is dependent upon the temperature of the aforesaid portion.