Abstract: The invention concerns a method for producing parts made of thin, light and rigid metal alloy essentially having the following steps: producing a core having the part shape; producing cavities in the core; producing shells made of metal alloy combined with reinforcing fibers with high modulus of elasticity; densifying the shells; and diffusion welding of the shells on the core by compression at temperature and pressure conditions for isothermal forging of the metal alloy used.

Abstract: A ceramic heat barrier coating is deposited on a substrate so that the coating has a columnar growth pattern which is interrupted and repeated a number of times throughout its thickness by successive regermination of the ceramic deposit. The regermination is obtained by a vapour phase deposition process wherein a polluting gas is introduced intermittently during the deposition of the ceramic. The resulting ceramic coating has a lower thermal conductivity than conventional columnar ceramic coatings.

Abstract: The invention relates to a combustion chamber containing a number of aerohanical injectors mounted in the end of the chamber that connects the upstream end of two annular walls and which are supplied with fuel permanently during operation. The injectors are arranged in two concentric rows around the axis of symmetry and in pairs in longitudinal planes passing through the axis of symmetry. The injectors of the two rows are more or less equidistant from the outlet of the chamber and have axes directed toward the outlet. A carefully considered distribution of the primary holes, dilution holes and the air flow allows the emissions of oxides of nitrogen to be reduced.

Abstract: A fuel injection system is disclosed for a gas turbine engine having a fuel injector issuing a primary fuel flow during all operating modes of the gas turbine engine and a secondary fuel flow when operating parameters of the gas turbine engine exceed predetermined values. The fuel injection system includes a first air swirler, a second air swirler located rearwardly of the first air swirler and a venturi having a wall with a converging-diverging inner wall surface forming a venturi throat, the venturi being located such that the wall separates first and second air flows issuing from the first and second air swirlers and such that the primary fuel flow emanating from the fuel injector in a conical configuration does not impact against the inner wall surface of the venturi.

Abstract: Composite material comprising a CAS+BAS vitroceramic matrix reinforced with SiC fibers and exhibiting a small difference between the thermal expansion coefficients of the matrix and the fibers is obtained by using a matrix having a BaO/(BaO+CaO) molar ratio of between 25% and 55% and predominant phases of triclinic anorthite and monoclinic celsian.

Abstract: The present invention relates to a device for optically measuring the temperatures of cryogenic fluids by analyzing the decay in the luminescence of a doped crystal, the device comprising a light source for exciting said crystal, an optical fiber for transporting the light flux emitted by said source to the crystal and for returning to a detection assembly the luminescent light emitted by the crystal as a result, and a measurement probe past which the fluid moves, wherein the doped crystal is constituted by one of the crystals from the group comprising strontium fluoride doped with divalent ytterbium, SrF.sub.2 :Yb.sup.2+ ; and calcium fluoride doped with divalent ytterbium, CaF.sub.2 :Yb.sup.2+. The crystal is placed at an interior end of a housing constituting the probe. The fiber has a surrounding capillary being placed in the housing facing the covering. A chamber is defined between the end of the fiber and the covering.

Abstract: An oxidizer control device for controlling the amount of oxidizer passing into a combustion chamber of a gas turbine engine. The device has first and second diaphragm assemblies located adjacent to each other at a front portion of the chamber. The first diaphragm assembly has a first, generally annular member with a plurality of circumferentially spaced apart vanes, adjacent vanes forming first oxidizer passageways therebetween, the first passageways opening through a periphery of the first member, and a second generally annular member extending around the periphery of the first member, the second member having a plurality of circumferentially spaced apart first orifices equal in number to the number of first passageways and being fixedly attached to the engine structure.

Abstract: A gas turbine engine combustion chamber bounded by inner and outer annular walls extending around a longitudinal axis of the engine and connected by an end wall, through which extend a plurality of fuel injectors, each with an intake air swirler. The outer annular wall has a plurality of first orifices arranged in a common plane and spaced apart in a circumferential direction such that each first orifice is circumferentially associated with a fuel injector and is located on one side of a radius line extending from the longitudinal axis and passing through the axis of the associated fuel injector, and a plurality of second orifices in the inner annular wall arranged in a common plane and spaced apart in a circumferential direction such that each second orifice is circumferentially associated with a fuel injector and is located on an opposite side of the radius line from the first orifice associated with the same fuel injector.

Abstract: A wall is disclosed for a gas turbine engine combustion chamber having a generally annular configuration around a central axis wherein the wall has an inner surface bounding at least a portion of the combustion chamber and a plurality of rows of cooling openings, each cooling opening having an elongated, generally rectangular configuration with a length l and a width e such that l is greater than e, the cooling openings in each row being equidistantly spaced apart a distance d in which d is not greater than the length l. The cooling openings of a given row are circumferentially displaced from cooling openings of an adjacent row and, since the distance d is not greater than the length l of the cooling openings, the opening areas overlap in adjacent rows to provide an even distribution of the cooling film within the combustion chamber.

Abstract: A variable geometry exhaust nozzle is disclosed in which the follower flaps of the first, upstream ring of flaps and the second, downstream ring of flaps have a seal to seal the gap between the upstream and downstream follower flaps throughout the range of movement of the variable nozzle flaps. The sealing device has a plate extending between the downstream edge portion of an upstream follower flap and the upstream edge portion of a downstream follower flap and across the entire circumferential width of the flaps. The plate has an upstream portion pivotally connected with the downstream edge portion of the upstream follower flap and a downstream portion which has a bead pivotally contacting an inner surface of the upstream edge portion of a downstream follower flap.

Abstract: The disclosed invention relates to a sealing device for the rotor blades of a gas turbine engine which permits real time adjustment to be made of the clearances between the rotor blade tips and the sealing structure. The sealing shroud around the turbine wheel is formed of sectors, each sector being attached to a monolithic short response time ring and a monolithic long response time ring. Ventilating air from upstream of the turbine wheel is directed onto the rings such that the sectors are caused to radially expand or contract in compliance with the expansion or contraction of the tips of the rotor blades during stabilized and transient engine operational modes. A small positive clearance between the sealing sectors and the blade tips is maintained throughout the range of the engine's operation.

Abstract: A method of producing a fibre-reinforced metallic circular part having a tral hollow, wherein the reinforcing fibres are disposed in the part in the vicinity of the hollow, comprises providing an annular metallic blank with a channel-sectioned groove opening towards the axis of the blank, placing uncompressed concentric layers of the reinforcing fibres and additional metal alternately in the groove followed by a more rigid expansion ring, evacuating the groove and sealing it by a deformable closure member which covers the groove, placing this assembly in an autoclave and subjecting it to a temperature and pressure sufficient to effect superplastic forging of the layers of additional metal whereby the fibre layers and the additional metal layers are compressed and welded to the blank in a single operation, and machining the resulting assembly to obtain the required shaped part.

Abstract: A combustion chamber for a gas-turbine engine is disclosed in which the walls defining the combustion chamber may be easily attached to and removed from the engine structure. A dome member is attached to the engine structure such that it partially encloses the fuel injector nozzle in an upstream direction. The shape of the dome-member is such that it splits the incoming oxidizer flow into inner and outer flows which pass along the inner and outer sides of the combustion chamber. The inner and outer walls of the combustion chamber may be attached to an upstream end wall of the combustion chamber such that this assembly is removable as a unit from the dome member. The inner and outer walls, as well as the end wall, are releasably attached to the dome member such that the assembly can be removed from the gas-turbine engine without the necessity of removing or displacing the fuel injector nozzles or the dome member.

Abstract: A removable inspection hole plug for sealing a plurality of inspection holes formed in a double-walled enclosure is disclosed in which individual sealing units are disposed in each of the inspection holes, with the individual sealing units linked together by a link rod pivotally attached to each of the sealing units. A seal is provided on each of the sealing units which slideably engages a wall defining the inspection hole and the link rod may be attached to the sealing units by a ball and socket swivel joint. One of the sealing units is attached to a housing which is, in turn, removably attached to the enclosure such that the sealing unit may undergo limited axial movement relative to the housing. This accommodates differential thermal expansion between the walls of the enclosures and also facilitates removal of the inspection hole plug by merely unfastening the housing from the enclosure and removing the housing along with the sealing units.

Abstract: An anti-icing system to prevent the formation of ice on, or to remove ice from selected portions of a gas turbine engine is disclosed that is not directly dependent upon the mode or speed of operation of the gas turbine engine. The system has a heat exchanger into which flows a tapped portion of air from the compressor and fuel from the engines fuel supply system. The fuel supply system includes a fuel return circuit which connects the fuel pump outlet to the fuel pump inlet so as to return or recycle fuel to the fuel pump inlet when the engine demand for fuel is low, such as under lower power operating conditions. This recycling of the fuel raises the temperature of the fuel such that, in the heat exchanger, heat is transferred to the tapped portion of the air from the compressor thereby raising the temperature of such tapped air such that it may be directed onto selected portions of the gas turbine engine to either prevent formation of ice, or to remove ice from these portions.

Abstract: A fuel/oxidizer pre-mixing combustion chamber for a turbojet engine is disclosed in which the pre-mixing device is incorporated into the upstream end wall structure of the combustion chamber. The upstream end portion of the combustion chamber, which is in communication with the oxidizer, has a plurality of generally radially extending, "V"-shaped members oriented such that the vertex of the "V" shape faces in an upstream direction. These members extend generally radially between the inner and outer walls which define the boundaries of the combustion chamber. The members define upstream edges and downstream edges which are axially the upstream edges. Fuel injectors extend radially inwardly between these members and are axially positioned between the locations of the upstream and downstream edges so as to spray fuel onto the adjacent sides of each of the members.

Abstract: A powder supply device for use in the formation of a coating by a laser beam treatment has its delivery pipe from the powder and carrier gas dispensing apparatus fitted with an expansion chamber into which the powder and gas enter via an inlet pipe carrying a powder diffuser. The expansion chamber has a conical part leading into an outlet pipe for carrying powder and gas to a discharge nozzle at a reduced rate determined by the rate of escape of gas from the expansion chamber via an exhaust pipe fitted with a flow regulator.

Abstract: A variable vane assembly for a gas turbine engine is disclosed having a disk member bearing against a recess formed in the inner surface of the gas turbine engine casing is formed separately from the vane. The disk member has a diametrical notch that accommodates a strip member formed integrally with the vane and which extends generally parallel to the chord of the vane. The control rod, which is also formed integrallly with the vane, passes through an opening defined by the disk member and is pivotally supported by the engine casing. A low friction sleeve may be interposed between the control rod and the opening defined by the engine casing to reduce the pivoting friction of the vane. This sleeve may be formed as a separate element, or may be formed integrally with the disk member, which may also be formed of low-friction material.

Abstract: A gas turbine engine is provided with a braking device for stopping the compressor drive turbine if a common shaft interconnecting the turbine and compressor rotors breaks, the braking device including a conical ring carried by the turbine rotor at its downstream end and a structural member of a generally conical shape carried by the upstream end of the turbine exhaust casing such that the ring will frictionally interlock with the structural member if the shaft breaks.

Abstract: A stator vane array is made by cutting vane blanks from a machined linear bar having a predetermined trapezoidal section using a wire tool electroerosion machine, the blanks being cut to an outline which conforms to the shape of the head and root portions of each vane. Each blank is then machined by electroerosion or by chemical machining to form the back and the face of the blade of the vane, and after carrying out finishing operations the vanes are butt-welded together edge to edge to form a complete annular array or a sector thereof. The method is particularly applicable to the manufacture of stator arrays for turbomachine compressors in which the stator vanes have blades with an evolutive profile.