Abstract: A separator-diffuser for a gas turbine engine is disclosed wherein the diffuser includes axial walls which function as a guide vane stage for the oxidizer compressor. By incorporating the last, or downstream, guide vane stage into the diffuser structure, the overall axial length and bulk of the gas turbine engine may be significantly reduced. The separator-diffuser has a wall defining a generally annular oxidizer flow passage extending around the central axis of the gas turbine engine, the passage having an oxidizer inlet located downstream of the last rotor stage of the oxidizer compressor so as to enable the oxidizer to pass from the oxidizer compressor into the oxidizer flow passage. A generally annular separator member is located in the oxidizer flow passage downstream of the oxidizer inlet so as to divide the oxidizer flow passage into at least two separate oxidizer flow paths, each flow path having a separate oxidizer outlet.

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 pre-mixing injection system to feed a fuel/air mixture to a combustion zone in a turbojet engine combustion chamber is disclosed having a pre-mixing tube defining a convergent pre-mixing zone and a diverging intermediate zone between the fuel and air injection devices, and the combustion zone of the combustion chamber. The convergent pre-mixing zone has an inlet adjacent to the fuel injector and air swirlers to accept the fuel/air mixture into the pre-mixing tube. The pre-mixing zone converges in a direction from the inlet to an outlet which is in communication with the inlet of the divergent intermediate zone. The divergent intermediate zone has an outlet which is, in turn, in communication with the combustion zone of the turbojet engine combustion chamber. The divergent intermediate zone is defined by an inner wall and an outer wall spaced from the inner wall so as to define a generally frusto-conical chamber between them.

Abstract: A wall structure for a gas turbine engine structure, such as a combustion chamber or an afterburner duct is disclosed having a plurality of cooling orifices formed through the wall located in a plurality of odd and even transverse rows, each row having a plurality of cooling orifices located in a plane extending substantially perpendicular to a longitudinal axis of symmetry with the cooling orifices of each odd and even row being circumferentially offset from the cooling orifices of the adjacent upstream corresponding odd and even row. The cooling orifices have a common diameter D and are circumferentially offset a distance d such that distance d is between 0.5 D and D. The axes of the orifices in the odd numbered rows lie on a first main line extending obliquely to the longitudinal axis of symmetry and to the oxidizer air flow, and the axes of orifices on the even numbered rows lie on a second main line, also extending obliquely to the longitudinal axis of symmetry and to the oxidizer air flow.

Abstract: An improved turbine vane structure is disclosed which enables more effective cooling and the reduction of temperature gradients along its length. The hollow interior of the vane is divided into three separate cavities, two upstream cavities and a downstream cavity. The downstream cavity is partially filled with a body of porous, heat transfer material. Cooling air flows through the downstream cavity in a direction counter to the hot gases passing over the exterior surface of the vane so as to increase the heat exchange properties. The two upstream cavities lie adjacent to each other and are supplied with cooling air from opposite directions to achieve a counterflow, heat exchange effect. Several sets of cooling holes are provided through the vane wall to communicate with the interior cavities and supply cooling air to the exterior surface of the vane.

Abstract: An apparatus for detecting fuel vapors in a turbojet engine oil tank is disclosed which incorporates a device in the oil tank which senses the presence of fuel vapors in the oil tank. The device has a housing defining an inner chamber in which a piston is slidably located. An actuating cartridge is also located in the chamber between an end wall of the housing and the piston. The cartridge comprises a material which expands in volume when subjected to heat and one which produces an exothermic reaction in the presence of fuel vapors. The housing defines one or more orifices to enable the atmosphere within the tank to communicate with the actuating cartridge.

Abstract: The present invention relates to a system for cooling a high power fuel injector of a dual fuel injector wherein the system comprises a first fuel supply circuit having a first conduit connecting a fuel feed supply and the high power fuel injector, the first conduit having a terminal end adjacent to a distal end of the high power fuel injector, and a second conduit connecting the terminal end of the first conduit to the low power fuel injector such that all of the fuel supplied to the low power injector first passes through the high power fuel injector. The system also has a second fuel supply circuit, separate from the first fuel supply circuit, which comprises a third conduit connecting the fuel feed supply and the fuel injection orifices of the high power fuel injector so as to supply fuel to the fuel injection orifices.

Abstract: Disclosed is a variable supersonic nozzle for a turbojet engine having an improved control system for varying the convergent and divergent nozzle flaps. All of the flaps are supported on several beams about the circumference of a gas passage. A control linkage interconnects hydraulic control cylinders, which are also mounted on the beams, with the convergent and divergent flaps such that, as the piston rod of the hydraulic control system extends and retracts, the angles of the flaps are varied accordingly. Additionally, cold flaps may be attached to the beams and interconnected with the linkage system such that their positions may also be varied by the control cylinder.

Abstract: The present invention relates to a method and apparatus for supplying fuel to and cooling a fuel injector of a gas turbine engine having a dual head combustion chamber. The method comprises the steps of supplying a total fuel flow to the fuel injector such that at least a portion of the total fuel flow circulates through the high power injector nozzle during all operational modes of the gas turbine engine, including those modes in which the high power injector is not supplying fuel to the combustion chamber, and evacuating unused fuel from the high power injector.

Abstract: Convergent flaps of a jet engine nozzle are controlled by actuating cylinders through actuating levers hinged to the fixed structure of the engine and by connecting rods. Divergent flaps are slaved to the convergent flaps by connecting rods themselves driven by the actuating levers. Cold flaps not hinged to the divergent flaps are slaved to the convergent flaps by further connecting rods connected to the first-named connecting rods.

Abstract: A stator vane mounting platform is disclosed which provides internal cooling chambers which facilitates the flow of cooling air through the chambers and thus, the cooling of the stator assembly. Baffles define an upstream chamber and a downstream cooling chamber between adjacent stator vanes so as to maximize the airflow and, consequently, the cooling effects of this airflow. The internal cooling chambers are defined by a thick wall and a relatively thin wall, the thin wall being in direct contact with the hot gases passing through the stator assembly. Mounting lugs and flanges are directly attached to the thicker wall so as to mount the stator assembly to the turbine engine structure and to accommodate all of the mechanical stresses encountered during the turbine engine operation.

Abstract: A turbojet engine has an outlet duct to which an annular array of actuating cylinders for nozzle flaps are hinged. The housings for the cylinders are connected together by transverse members to form a rigid structure coaxial with the outlet duct. The arrangement includes convergent flaps and slaving devices for divergent flaps, all hinged to the rigid structure and particularly to the housings.

Abstract: A self regulating bleed valve for a gas turbine engine is provided which taps or bleeds a portion of a gas, typically air, from a duct of the gas turbine having a wall bounding the gas flow. The bleed valve has a valve member pivotally attached to the wall such that the valve member extends through a main opening formed in the wall. The valve member has an internal cavity in communication with a gas inlet opening and a gas exhaust opening and is pivotally movable between an extended position wherein the gas inlet opening portion of the valve member extends into the gas flow duct such that the inlet opening faces generally in an upstream direction so as to deflect a portion of gas flow into the internal cavity, and a retracted position wherein the inlet opening extends obliquely, generally parallel, to the gas flow so as to minimize the air tapped or bled from the gas flow.

Abstract: A fuel supply system for a gas turbine engine is disclosed which incorporates a discharge conduit into the fuel supply system such that an increase in the temperature of the fuel in the fuel injector conduits after engine shut-down will cause a valve in the discharge line to open before the opening of the valve in the fuel injector conduit, thereby directing excess fuel to a receiver or a tank, rather than into the hot combustion chamber. A fuel flow valve is connected to the fuel supply conduit, the discharge conduit, as well as the fuel injector conduits. Under normal operating conditions, a valve member within the fuel flow valve is positioned so as to enable communication between the fuel feed conduit and the fuel injector conduits so that fuel may be supplied to the fuel injectors. When the valve element is moved the a second position, after engine shut-down, it seals off the fuel feed conduit and enables communication between the fuel injector conduits and the discharge conduit.

Abstract: A gas flow separator for an annular combustion chamber of a gas turbine engine is disclosed in which the radially spaced apart first and second gas flow separator walls which extend axially into the combustion chamber from the combustion chamber upstream end wall each define a plurality of axially extending channels. Each of the channels extends generally axially in an upstream direction from the downstream edge of each of the separator walls such that their axial lengths are less than the axial lengths of the respective separator walls. Both the depth and the width of each of the channels increases from its upstream end point to the downstream edges of the separator walls. The channels may be circumferentially aligned with each other, or the channels of one separator wall may be circumferentially offset from the channels of the other separator wall.

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 rotary valve assembly is disclosed in which a rotary valve member is located within a casing having one or more fluid inlets and a plurality of fluid outlets. The rotary valve member has a fluid conduit which extends in a generally radial direction and which communicates with the fluid inlet. Fluid orifices communicate with the fluid conduit and exit through opposite sides of the rotary valve member to thereby minimize, or eliminate altogether, axial forces acting on the rotary valve member. Fluid outlet passages communicate with the two fluid orifices during at least pan of the rotation of the rotary valve member to direct the pressurized fluid to the valve outlets. The rotary valve may include a pair of rotary valve members drivingly connected to each other such that they rotate synchronously. The connection may include gear teeth formed on the adjacent peripheries of the rotary valve members such that rotation of one of the valve members causes rotation of the other.

Abstract: A nozzle comprises: a set of first flaps articulated to a rigid structure, and forming a convergent; a set of second flaps each articulated to a corresponding first flap, and forming a divergent; a set of third flaps each of which is connected at a position between two adjacent second flaps and which is, on the one hand, articulated to the rigid structure and, on the other hand, linked to each of the two adjacent second flaps by carrier linked to the aforesaid third flap by a ball joint.

Abstract: A control device makes it possible to rapidly shift the bleed valves of an aircraft turbojet engine to a large opening position when the engine is under low power operation in order to prevent flame-out. The device allows for instantaneously interrupting the action of a control return cable when the valves are open from a certain given value. The device includes a drive support integral with a crank handle, in order to bring about the translation of the return cable, when the latter is not blocked by a translation stop member. The control device is used for opening of bleed valves of turbojet engines having two concentric annular jets.

Abstract: A method and apparatus for detecting internal defects in a workpiece are disclosed which uses time inversion to invert echo signals received by a transducer from the workpiece with respect to the signal shape and its time distribution and retransmits the inverted signal onto the workpiece. The method involves transmitting an unfocused ultrasonic beam onto the workpiece, receiving an echo signal from the workpiece, storing the first echo signal and inverting the first echo signal from each transducer with respect to the signal shape and time sequence. The inverted signal is transferred to a memory and the aforementioned procedure is carried out for each of the inspection zones n on the workpiece. The stored, inverted first echo signals are then transmitted onto the workpiece, each inverted signal being transmitted onto the inspection zone n from which the non-inverted first echo signal was received.