Abstract: A component, e.g. an aerofoil component like a turbine-blade or guide-vane, for a gas turbine engine, including first and second walls defining at least one passage for supply of cooling fluid to a portion of the component to be cooled, the portion including a slot via which cooling fluid passes from the passage to exit of slot for effecting cooling of the portion, wherein the slot includes at least one side wall, pair of opposite side walls, each having surface profile defining array of channels for passage of cooling fluid, and surface profile defining each of arrays of channels is undulating with the respective arrays of channels in two side walls being angled with respect to one another. The resulting internal cross-corrugated cooling arrangement promotes enhanced cooling of the trailing edge or other portion of the component by controlling flow rate of cooling air through slot and exhausted therefrom.

Abstract: A component, e.g. an aerofoil component like a turbine-blade or guide-vane, for a gas turbine engine, including first and second walls defining at least one passage for supply of cooling fluid to a portion of the component to be cooled, the portion including a slot via which cooling fluid passes from the passage to exit of slot for effecting cooling of the portion, wherein the slot includes at least one side wall, pair of opposite side walls, each having surface profile defining array of channels for passage of cooling fluid, and surface profile defining each of arrays of channels is undulating with the respective arrays of channels in two side walls being angled with respect to one another. The resulting internal cross-corrugated cooling arrangement promotes enhanced cooling of the trailing edge or other portion of the component by controlling flow rate of cooling air through slot and exhausted therefrom.

Abstract: An air-cooled component such as a turbine stator vane, has a row of cooling passages extending from the interior of the vane to the exterior. The passages are inclined to a plane perpendicular to the row. The angle of inclination of each passage varies with the position of the passage along the row. The arrangement assists in avoiding local overheating of the vane surface.

Abstract: A method and apparatus for detecting and avoiding an underground object during a horizontal directional drilling operation. The apparatus comprises a boring tool with a ground penetrating radar detection system. The boring tool is operatively connected to a drill string and advanced through the earth to create a borehole. The radar detection system includes at least one transmitter, at least one detector, and a processor. The transmitter is located on a surface of the boring tool and is adapted to transmit electromagnetic waves. At least one detector is located on the surface of the boring tool, and detects the electromagnetic waves reflected by underground objects. The processor determines the location of the underground object from characteristics of the reflected waves. Using this information, the drill string may be pulled back up the borehole or redirected to avoid the object. The boring tool may be caused to breakout of the existing borehole using a pivoting boring tool.

Abstract: A turbine nozzle guide vane 10 with passages 28 leading from a hollow core 32 to respective seal strip slots 20, to deliver cooling air to abutment faces 18 on each end of the vane 10.

Abstract: A turbine nozzle guide vane 10 with passages 28 leading from a hollow core 32 to respective seal strip slots 20, to deliver cooling air to abutment faces 18 on each end of the vane 10.

Abstract: An air-cooled component such as a turbine stator vane, has a row of cooling passages 8 extending from the interior 4 of the vane to the exterior. The passages 8 are inclined to a plane perpendicular to the row. The angle of inclination of each passage 8 varies with the position of the passage 8 along the row. The arrangement assists in avoiding local overheating of the vane surface.

Abstract: A gas turbine aerofoil with at least one internal cavity for conveying cooling fluid through the aerofoil has at least one internal cavity adjacent the aerofoil leading edge, at least one impingement cooling passage extending from, and in flow communication with the cavity, and at least one film cooling hole extending from, and in flow communication with, the cooling passage. The impingement passage extends into the aerofoil wall in the region of the leading edge and opens into the film cooling hole. The cooling hole extends through the aerofoil wall to an external surface of the aerofoil at a position downstream of the leading edge such that, in use, cooling fluid from the cavity exits the cooling passage into the cooling hole as an impingement jet against the internal surface of the cooling hole in the region of the leading edge.

Abstract: A gas turbine aerofoil with at least one internal cavity for conveying cooling fluid through the aerofoil has at least one internal cavity adjacent the aerofoil leading edge, at least one impingement cooling passage extending from, and in flow communication with the cavity, and at least one film cooling hole extending from, and in flow communication with, the cooling passage. The impingement passage extends into the aerofoil wall in the region of the leading edge and opens into the film cooling hole. The cooling hole extends through the aerofoil wall to an external surface of the aerofoil at a position downstream of the leading edge such that, in use, cooling fluid from the cavity exits the cooling passage into the cooling hole as an impingement jet against the internal surface of the cooling hole in the region of the leading edge.

Abstract: A hollow airfoil (8) has an internal air system in which a cooling gap (44) adjacent the internal surface (52) is formed by a liner insert (14) consisting of a shaped panel (14a). At least some of the cooling air circulating through the gap (44) enters through a screening arrangement, comprising exclusion apertures (50), which removes particulates over a predetermined size (e). The air is fed into a plenum chamber (46) which may be formed by a pressing in the insert panel (14a). There are two exits from the plenum (46): a first is through the screening arrangement to admit filtered air to the wall cooling gap (44), and a second is via apertures (54) in the airfoil wall (18) the sizes (d) of which apertures are large enough to pass the screened particulates into the gas path.

Abstract: Means for reducing blockage of cooling apertures in a hollow gas turbine guide vane by sand or other particles entrained in cooling air, is provided by a partition within the vane for dividing the hollow region into first and second regions, the first region having a flow of high pressure cooling air, the second region being at a pressure lower than the first region. The partition is provided with a channel on the high pressure side. Apertures are located in the base of the channel providing flow between the first and second regions and directing cooling air at the inside surface of the vane. The inlet area of the channel is greater than the total cross-section area of the apertures, and the width of the channel distal to its base is less than or equal to the diameter of the apertures, thus trapping in the channel entrained particles larger than the diameter of the apertures.