Abstract: An apparatus for pre-stressing a component, the apparatus includes means to direct a beam of radiation in a path through a medium adjacent to the component between a pair of electrodes to produce ionisation in the path through the medium and means to produce an electrical discharge between the pair of electrodes in the path through the medium to produce a pressure pulse in the medium adjacent to the component without the electrical discharge directly contacting the component, the pressure pulse impacting a surface of the component to produce a region of compressive residual stress within the component.

Abstract: A joint assembly for securing flanges of two casings comprising a plurality of bolts, a plurality of collars and a plurality of nuts. Each bolt extends through an aperture in the first flange and an aperture in the second flange, each collar being arranged around a shank of a respective bolt and each nut being secured on a respective one of the bolts. Each collar being arranged between one of the flanges and a nut or a head of a bolt. Each collar comprises a first member and a second member, the second member being arranged at a first end of the first member. The second member being substantially U-shaped in cross-section, the second member having first and second radially inner ends and a radially outer mid portion and an axial space is defined between the first radially inner end and the second radially inner end of the second member.

Abstract: A vane is provided for directing hot gases in a gas turbine engine. The vane includes a hollow aerofoil portion, which in use spans the working gas annulus of the engine. The vane further includes an impingement tube which forms a covering over the interior surface of the aerofoil portion and which has jet-forming apertures formed therein for the production of impingement cooling jets. The impingement tube includes two tube portions which are separately insertable into position into the aerofoil portion to form the covering. The o impingement tube further includes an expansion member which, when the tube portions are in position in the aerofoil portion, is locatable in the aerofoil portion to urge each tube portion outwardly and thereby holds the tube portions in position against the aerofoil portion.

Abstract: A component of a turbine stage of a gas turbine engine is provided, the component forming an endwall for the working gas annulus of the stage. The component has one or more internal plena behind the endwall which, in use, contain a flow of cooling air. The component further has a plurality of exhaust holes in the endwall. The holes connect the plena to a gas-washed surface of the endwall such that the cooling air effuses through the holes to form a cooling film over the gas-washed surface. Each exhaust hole has a flow cross-sectional area which is greater at an intermediate position between the entrance of the hole from the respective plenum and the exit of the hole to the gas-washed surface than it is at said exit.

Abstract: A blade assembly for a rotary component comprises an aerofoil member and a displacement apparatus on the aerofoil member for displacing a detached first portion of the aerofoil member in a rearward direction relative to a second portion of the aerofoil member. On failure of the aerofoil member, the displacement apparatus displaces the first portion from the second portion in the rearward direction.

Abstract: A method of repairing a component comprising: removing a damaged portion of the component to expose a region of the component; providing a patch having a rim exceeding the dimensions of the exposed region; placing the patch on the exposed region of the component such that the exposed region is covered by the patch and the rim is spaced apart from the exposed region; joining the patch to the component around the rim of the patch; and diffusion bonding the patch and the component together. The rim may be spaced apart from the exposed region such that the step of joining the patch to the component does not affect the exposed region. The method may further comprise machining a recess in the damaged region of the component.

Abstract: Electromagnetic damper (1) for rotating machines (100) having at least a stator (103) and a rotating shaft (100); the electromagnetic damper (1) is able to damper the vibrations of the rotating machine (100) during its functioning. The damper includes windings (2) of electrically conductor material, for generating a magnetic field; a magnetic circuit (4), for conveying within it a magnetic flux generated by the windings (2); a power supply (8), for supplying the windings (2) of electrically conductor material; the power supply (8) of the electromagnetic damper (1) is positioned inside the rotating machine (100).

Abstract: An aircraft wing has an engine attachment position at which a gas turbine engine is attached beneath the wing, in use the engine ejecting a propulsive gas jet with a jet shear layer being formed between the gas jet and the surrounding air. The aircraft wing further has one or more elongate, flow-modifying formations protruding from the underside of the wing. The length direction of the or each formation is along the fore and aft direction of the wing with the trailing edge of the formation being rearward of the trailing edge of the wing. The flow-modifying formations can be arranged such that they interact with the jet shear layer to reduce noise generated by the interaction of the jet shear layer and the wing. They can also be arranged to block, attenuate and/or to scatter the noise reflected by the wing.

Abstract: Carbon dioxide recirculating apparatus (20, 120) is disclosed for use in an arrangement having combination means (115) and a path for the flow of a gas through the combustion means (115). The apparatus (20, 120) comprises extraction means (221) for extracting carbon dioxide from a first region of the path downstream of the combustion means (115). It further includes condensing means (26, 30) for condensing the extracted carbon dioxide, and feed means (36, 136) for feeding the condensed carbon dioxide to a second region of the path upstream of the combustion means.

Abstract: Protection arrangements and methods of operating protection arrangements are important in order to maintain operability with regard to electrical power distribution networks. Such networks generally comprise grids or meshes of electrical distribution pathways from generators and electrical loads. Faults may occur within the network and circuit breakers or other protection elements are utilised to isolate such faults. A number of regimes for protection are known but problems can arise with regard to ensuring an appropriate pan of the distribution network is isolated.

Abstract: A blade for a rotor, such as a turbine rotor of a gas turbine engine, has a squealer tip comprising a peripheral wall which defines a cavity. A first region of the peripheral wall extends radially, with its outer surface forming a continuation of the adjacent aerofoil surface of the blade. A second region extends obliquely with respect to the radial direction and the adjacent part of the aerofoil surface. The second region defines a winglet, and serves to increase the width of the chamber towards the trailing edge of the blade.

Abstract: A ceramic seal segment for a shroud ring of a rotor of a gas turbine engine, the ceramic seal segment positioned radially adjacent the rotor and characterized by being a hollow section that defines an inlet and an outlet for the passage of coolant therethrough.

Abstract: Apparatus 200 for forming a composite component is disclosed, the apparatus comprising: a deformable mould tool 204 that at least partially defines a mould cavity 212; an interface layer 222 formed on an external surface of the mould tool 204; and at least two peristaltic actuators 206, mounted to contact the interface layer 222 and to generate a peristaltic pressure wave in the mould tool 204. The peristaltic actuators may comprise rollers 206, pistons 306 or bi-metallic blocks 406. A method of forming a composite component is also disclosed, the method employing a mould tool 204 that at least partially defines a mould cavity 212. The method comprises: placing reinforcing fibres into the mould cavity 212, forcing a matrix material into the mould cavity 212 through the reinforcing fibres, and generating a peristaltic pressure wave within the mould tool 204 during forcing of the matrix material into the mould cavity 212.

Abstract: A method of inspecting a component in an assembled gas turbine engine includes inserting a boroscope and a conduit through an aperture in a casing of the engine. The conduit has an applicator tip. The boroscope and conduit are directed to the component to be inspected. A dye penetrant is supplied through the conduit to the applicator tip. The applicator tip is arranged to contact the surface of the component and dye penetrant is supplied onto the surface of the component from the applicator tip such that the dye penetrant enters any defects in the surface of the component. The applicator tip includes a porous and malleable member. Light is directed onto the component and the surface of the component is viewed through the boroscope to determine if any defects are present in the surface of the component.

Abstract: A system is provided for mounting fuel injectors to a gas turbine engine. The system includes an engine casing having an aperture formed therein. The system further includes a plurality of fuel injectors having respective flanges for mounting the fuel injectors to the casing at the aperture so that the fuel injectors extend side-by-side into the engine. The flanges are dismountably sealed to an inner side of the casing. The aperture and the flanges are configured so that, when dismounted, each fuel injector can be rotated into an orientation relative to the aperture which allows the respective flange to pass though the aperture and the fuel injector to be withdrawn from the casing. The flanges have respective sealing formations which engage with their neighbouring flanges when the fuel injectors are mounted to the casing to close off the aperture and to form seals between the flanges.

Abstract: flow control arrangement for controlling the flow of lubricant discharged from a bearing includes a flow control member locatable, in use, adjacent to the bearing. The flow control member defines a generally radially outer edge and is rotatable to direct lubricant discharged onto the flow control member radially outwardly towards the outer edge for ejection therefrom.

Abstract: It is known that corrugated plate heat exchangers can have good thermal and hydraulic performance but limitations with regard to operational pressures whilst conventional tube type heat exchangers can achieve high pressure operation but can have high flow pressure losses due to the configuration of such tubes. By arranging a tube stack comprising respective tubes 2a, 3a arranged in layers typically one upon the other with cross junctions 4 between them and intersticial gaps between tubes it is possible to create swirling spinning motion in the flow possibly inside and at least outside the tubes for improved heat exchange with only limited flow restriction. The swirling flow in the heat exchanger matrix outside of the tubes passes along channels formed by the interconnecting intersticial gaps between the tubes and is guided about those tubes for heat exchange.

Abstract: An aerofoil for a gas turbine engine comprising a pressure wall and a suction wall and defining leading and trailing edges, the walls define a passage into which is supplied a cooling fluid, an array of cooling holes is provided through at least one of the walls to allow the cooling fluid to flow from an interior surface to an exterior surface. The array of holes comprise two groups, the holes of each group are angled to intersect the holes of the other group and are characterized in that the holes of at least one of the groups comprises two or more holes at different angles to one another to vary the porosity of the wall to account for otherwise varying wall temperatures. This arrangement also allows either less coolant mass flow to maintain a constant metal temperature, or a lower metal temperature for a given coolant mass flow.

Abstract: A fuel cell arrangement comprises at least one fuel cell module, each fuel cell module comprises a plurality of fuel cells. Each fuel cell module is hollow and defines a chamber. Each fuel cell module is arranged within an inner vessel and the inner vessel is arranged within an outer pressure vessel. Means to supply oxidant is arranged to supply oxidant to the space within the inner vessel so as to supply oxidant to the cathode electrodes. Means to supply fuel is arranged to supply fuel to the chamber in each fuel cell module so to supply fuel to the anode electrodes. The outer pressure vessel is protected from the high temperature environment of the fuel cells by the inner vessel. The outer pressure vessel forms the main pressure containment of the arrangement and operates at a lower temperature and operates with a greater safety margin than a single pressure vessel arrangement.

Abstract: Within hollow structures, such as blade structures in a gas turbine engine, traditionally rigid girdered reinforcement has been utilised to define structure and shape. Such rigid definition can inhibit utilisation of damping fillers within the hollow structure. By providing a web former comprising spaced bond areas suspended upon angled interconnecting membranes a hollow structure is achieved which is flexible and can be used in conjunction with a damping filler to achieve desired performance. The web former supports skins defining the shape and takes some load such that the damping filler does not separate within the hollow structure.