Abstract: The spiral heat exchanger (10) has a hot end (16) and a cold end (18) arranged at opposite ends of the heat exchanger (10). A first, relatively hot, fluid is supplied to the hot end (16) of the heat exchanger (10) and the first fluid is removed from the cold end (18) of the heat exchanger (10). The heat exchanger (10) comprises first and second metal sheets (12,14). Each metal sheet (12,14) has hot and cold edge portions (18,20) at the hot and cold ends (16,18) respectively of the heat exchanger (10). Both of the hot and cold edge portions (18) of the first metal sheet (12) are thinner and have a greater diameter than the remainder of the first metal sheet (12) such that both of the hot and cold edge portions (18) contact the hot and cold edge portions (20) of the second sheet (14). The hot and cold edge portions (18) of the first metal sheet are joined to the hot and cold edge portions (20) of the second metal sheet (14).

Abstract: A method of characterizing the vibration of a plurality of rotating blades (12), such as turbine blades in a gas turbine engine, includes the steps of providing a single strain gauge (16A) on a single one (12A) of the blades and providing either one or two tip timing probes (22A, 22B) on a casing surrounding the blades. The data from the strain gauge (16A) allows the vibration of the single blade (12A) to be fully characterized while the data from the tip timing probes (22A, 22B) allows the amplitudes or velocities of vibration of all the blades to be determined. The relationship between the data from the tip timing probes for the single blade (12A) and the stress data from the strain gauge may be established. This relationship may then be assumed to apply to all the blades, thus allowing the stresses induced in all the blades by the vibrations to be determined.

Abstract: A vane assembly 40 for use within a gas turbine engine has a main vane portion 42 with an internal cavity 44. A cavity insert 46 is located within the cavity 44, close to the wall 48 to define transpiration cooling paths. Cooling air leaves the insert 46 through apertures directed at the wall 48, to produce impingement cooling. The transpiration cooling paths are extended back to the trailing edge 66 by means of a fairing 54. The use of a fairing in addition to the insert allows more complicated cavity shapes to be filled.

Abstract: A turbofan gas turbine engine (10) comprises a fan rotor (32) carrying a plurality of radially extending fan blades (34). A fan blade containment assembly (38) surrounds the fan blades (34) and the fan blade containment assembly (34) comprises a generally annular, or frustoconical, cross-section casing (52). At least one corrugated sheet metal ring surrounds the casing (52) wherein the corrugations extend with axial and/or circumferential components.

Abstract: A rotor (38) for a gas turbine engine (10) has a low emissivity surface finish, or high emissivity surface finish (44), on at least a portion of its surface (42) to reduce temperature differentials between an upper portion and a lower portion of the rotor (38). This reduces bowing of the rotor (38) to allow the gas turbine engine (10) to be started without harmful vibrations of the rotor (38).

Abstract: A conformance gauge is used as an inspection tool to check that component features lie within tolerance limits. When the component has been designed using CAD tools the CAD data file defining external surfaces of the component is used as the basis to create a second CAD data file defining the surfaces of the inspection to conform to the corresponding surfaces of the component. Viewing apertures or slots are then defined in the data file to the tolerance limits of features to be checked. The second CAD data file is then provided to a rapid prototyping system, eg a stereolithography machine to produce the final inspection gauge.

Abstract: A seal assembly for co-operation with a shaft comprising a seal member which, in use, in a first position, forms a seal against the shaft, a seal housing for retaining the seal member, means for applying a radially inward force to the seal member and means for applying a radially outward force to the seal member so that, when the means for applying a radially outwards force is operated, the seal member is dilated to a second position thereby enabling the seal assembly and the shaft to be fitted and disassembled in conventional manner, when the means for applying a radially outward force is removed the means for applying a radially inward force to the seal member returns the seal member to the first position.

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: A brush seal (9) comprising a plurality of bristles packed together in a bristle layer (10). The bristles (10) extend from a first component (4) towards a facing surface of a second component (2). A movable plate (14) is disposed substantially parallel to and adjacent to the bristle layer (10). The plate (14) is movable relative to the bristle layer (10) in a direction parallel to the bristle layer (10). An edge (22) of the movable plate (14) adjacent to and facing the facing surface of the second component (2) is arranged to air ride on the facing surface of the second component (2). To promote the air riding the edge (22) of the movable plate (14) may be accordingly profiled. Alternatively the edge (14) may comprise an enlarged foot member (24) which defines an enlarged surface (26). Furthermore a recess (30) may be defined in the movable plate (14).

Abstract: Cooling air enters a cooling path 56 from a supply at 58. The path follows a serpentine path consecutively through a number of components to be cooled, including guide vanes 38, 40, blades 30, a shroud 54 and a shaft 18. A valve 68 is provided at the downstream end of the path 56. The setting of the valve 56 modulates the flow and pressure of air along the path 56, without wholly preventing it.

Abstract: The present invention provides for an etch and mar resistant low VOC clear coating composition most suitable for use as a top clear coat in multi-layered OEM or refinish automotive coatings. The coating composition includes isocyanate, carbonate and melamine components. The isocyanate component includes an aliphatic polyisocyanate. The composition may be formulated as a two-pack or one-pack coating composition, wherein the isocyanate functionalities are blocked with a blocker such as a mono-alcohol.

Abstract: The present invention relates to a method of manufacturing a through hole in a component between a first surface and a second surface, the through hole comprising a cavity formed in the first surface and a communicating passage between the second surface and the cavity comprising the steps of:

Abstract: A gas turbine engine nose cone (44) comprises a spinner (46) and a fairing (48). The spinner (46) has a conical upstream portion (50) and a cylindrical base portion (52). The fairing (48) is frustoconical and surrounds the base portion (52) of the spinner (46). The outer surface (68) of the fairing (48) forms a continuation of the outer surface (56) of the conical upstream portion (50) of the spinner (46). The outer surface (68) of the fairing (48) has a skin (80) to protect the fairing (48) from erosion and a protective member (86) extends around the upstream end (82) of the fairing (48) to retain the skin (80) on the upstream end (82) of the fairing (48).

Abstract: The performance of each component in the system is defined by performance parameters x, which are related to measurement parameters z expressed as a function h() of the performance parameters x and operating parameters w. The method comprises: (a) setting an assumed maximum number of fault affected components and defining a series of fault classes corresponding to possible outcomes in terms of faulty components, (b) creating an initial population of strings for each fault class, each comprising a plurality of elements corresponding to the performance and operating parameters (c) optimising for each class an objective function J(x,w) which gives a measure of the consistency between measured values and calculated values of the measurement parameters calculated using said function of the performance parameters and the operating parameters h(x,w), and (d) selecting the class having the best value of the objective functions.

Abstract: A thrust reverser cascade flow directing element (28) for a gas turbine engine (10) comprises a plurality of plates (30) and a plurality of flow directing vanes (40). At least one vane (40) extends between each pair of plates (30), the plurality of plates (30) are formed from sheet material and a single integral piece of ductile sheet material (32) forms the plurality of flow directing vanes (40). The single integral piece of ductile sheet material (32) has a plurality of longitudinally spaced apart apertures (36) and a plurality of longitudinally spaced apart sheet material portions (38) between the apertures (36) and the ductile sheet material (32) is bent at a plurality of longitudinally spaced positions such that each sheet material portion (38) defines one of the plurality of flow directing vanes (40).

Abstract: A turbine assembly (35) for a gas turbine engine (10) comprises a rotatable support arrangement (38) which comprises means for mounting thereon a plurality of turbine blades (36). The turbine assembly (35) defines flow path means (43) for a flow of cooling fluid therethrough. The flow path means (43) is connectable to a supply of relatively cold cooling fluid. The flow path means 43 is arranged such that the relatively cold cooling fluid is driven radially outwardly through the flow path means (43) substantially wholly by the centrifugal force generated the rotation of the turbine assembly (35) in operation. Relatively hot cooling fluid is displaced by the relatively cold cooling fluid radially inwardly through the flow path means (43).

Abstract: In one aspect the invention provided a friction welded component comprising at least two structural support members spaced apart and connected by a plurality of first and second studs. Each of the first studs are friction welded at one end to a first of the support members and at the opposite end thereof to one end of a respective second stud. Each of the second studs are friction welded to a respective first stud and a second of the support members along a continuous annular friction welded joint having a frusto-conical configuration.

Abstract: A method of manufacturing a leaf seal for use between rotating components comprises forming corrugations within a metallic strip and feeding the corrugated strip into a seal guide. The corrugated strip is then pressed into the guide by an angled ram such that the corrugations lie at an acute angle to the perpendicular axis. The strip is then secured in a seal carrier, the free ends of the corrugations thus forming the angled sealing leaves of a leaf seal.

Abstract: A joint for joining a first metal sheet (10) to a second metal sheet (30) comprises a plurality of projections (18) on the edge (12) of the first metal sheet (10). The projections (18) are symmetrical about a plane extending perpendicularly to the plane of the first metal sheet (10). The symmetrical projections (18) are rotatable about an axis (X), the axis (X) is arranged in the plane of the first metal sheet (10) and in the plane extending perpendicularly to the first metal sheet (10). A plurality of slots (32) are provided through the second metal sheet (30). The symmetrical projections (18) extend through the slots (32) in the second metal sheet (30) and the symmetrical projections (18) are rotated such that the symmetrical projections (18) are arranged in the plane perpendicular to the plane of the first metal sheet (10) to clamp the second metal sheet (30) between the edge (12) of the first metal sheet (10) and symmetrical projections (18).

Abstract: A particle vibration damper for a vibrating component is disclosed which comprises a body having a chamber and a plurality of particles, wherein the chamber is partially filled with the plurality of particles, the particle vibration damper, in use, is disposed on or in a vibrating component.