Abstract: A variable geometry pre-mixing fuel injector (50) for injecting a fuel/air mix in a downstream direction, comprising: an air inlet (60); a fuel inlet (58) positioned downstream of the air inlet (60); a duct (56) extending at least downstream of the fuel inlet (58) to define a fuel and air pre-mixing zone (62), that narrows to form an opening (64); and means for varying the flow of fuel/air mix from the pre-mixing zone (62) through the opening (64).

Abstract: A fuel control system for a gas turbine engine is disclosed that includes a flow path carrying fuel from a fuel source to a combustion chamber, an ecology valve 124 for removing a quantity of fuel from the flow path, the ecology valve 124 being shiftable in a first direction from a first position to a second position and in a second direction from said second position to said first position and a fuel line 115 connected between the flow path and the ecology valve 124 for moving fuel between the flow path and the ecology valve 124 to bias the ecology valve 124 toward the second position, where the fuel line 115 is configured, such as by the inclusion of an orificed check valve 150 therein, to allow fuel to move therethrough away from the ecology valve 124 at a greater rate than toward the ecology valve 124.

Abstract: An automatic recovery pilot nozzle support system for supporting a pilot nozzle in a fuel injection system of a turbine engine. The support system includes a sleeve extending from an orifice in a support housing, wherein the sleeve has a hollow opening for containing a pilot nozzle. The sleeve may increase the natural frequency of the pilot nozzle above an excitation zone, thereby limiting destructive vibrations. The sleeve may be attached to the support housing with an interference fit. The automatic recovery aspect of the support system enables the sleeve to maintain an interference fit with the support housing such that anytime the sleeve looses contact with the support housing, an insulative film of air forms between the sleeve and the support housing. The insulative film of air causes the temperature of the sleeve to increase, and the sleeve to expand and reform the interference fit with the support housing.

Abstract: A pump control system (20) for a pump (21) in a gas turbine engine (10) is described. The pump control system (20) comprises demand means (22) for providing a demand signal (23) relating to a required rate of fluid flow and/or pressure from the pump (21). The system also comprises sensing means (26) to sense at least one parameter of fluid downstream of the pump (21) and to provide at least one feedback signal (28) relating to the, or each, respective parameter. Comparator means (30) is provided for comparing the demand signal (23) with the, or at least one, feedback signal to provide a control signal (33) for controlling the pump.

Abstract: A duct that preferably includes a low loss inlet section is configured to include one or more flow limiting passages that extend through a portion of the low loss inlet section. The flow limiting passages are located and configured such that in the desired operating flow range of the duct, the fluid exiting the flow limiting passages has minimal effect on fluid flow into and through the duct. However, at relatively high pressure ratios, the fluid exiting the flow limiting passages will disturb the fluid entering the duct, causing mixing and shock losses, which will limit the fluid flow rate into and through the duct.

Abstract: A turbojet diffuser disposed between a compressor and a combustion chamber, and secured to an outer upstream annular flange of an outer casing of the combustion chamber by suspension means which comprise a first frustoconical wall extending from the outer longitudinal wall of the diffuser towards the combustion chamber, and a second frustoconical wall extending towards the compressor between the first frustoconical wall and the outer casing of the combustion chamber.

Abstract: The present invention provides a multiple manifold fuel metering system with a separate motor, pump, and shut-off/purge valve for each manifold. The present invention may be used for metering fuel to any engine, especially a gas turbine engine. The fuel metering system of the present invention has the capability of independently controlling fuel flow during transitions in engine operation or allowing fuel to flow simultaneously through all manifolds to prevent blowout, optimizing combustion temperature distributions, or minimizing combustion emissions. Brushless DC variable speed electric motors may be used to drive pumps with highly accurate speed control to accurately control fuel flow rate to each of a plurality of manifolds of a fuel metering system. With brushless DC motors, motor speed may be controlled within a revolution for smoothing fuel delivery to an engine.

Abstract: One embodiment of the invention provides a turbine control system that adjusts the control thresholds of two-position valves, which provide propellant to the turbine, based on turbine load so as to compensate for increased turbine speed overshoot at low load and the increased turbine speed undershoot at high load. These two-position on-off modulated valves are used in a bang-bang (fully open or fully closed) regulation scheme to eliminate or minimize speed droop by using variable speed bounds implemented as a function of load.

Abstract: A method and apparatus for turbine overspeed protection, useful for steam and gas turbines, is disclosed. The apparatus comprises a spring-loaded rod held by a plurality of energized solenoids in an operating position any time the turbine's shaft rotational speed is less than a trip rotational speed set-point. When the rotational speed reaches the trip rotational speed set-point, both solenoids are de-energized and the spring-loaded rod moves to provide turbine trip. Increased reliability of the solenoids is provided by compressing the spring during the resetting of the rod with an additional electromechanical actuator and by using a plurality of solenoids, each of which is able to provide the force required to hold the spring in its compressed state.

Abstract: An oxygen fired power generation system is disclosed. The power generation system has a high pressure combustor having a water recycle temperature control subassembly, and an intermediate pressure combustor having a CO2 recycle temperature control subassembly. Thus, a first energy cycle utilizes a first energy source operatively associated with a corresponding first heat sink, and a first inert agent to provide energy transfer therebetween and temperature control during operation of the first energy source. In like fashion, a second energy cycle utilizes a second energy source operatively associated with a corresponding second heat sink, and a second inert agent to provide energy transfer therebetween and temperature control during operation of the second energy source. The first and second energy sources are not identical, the first and second heat sinks are not identical and the first and second inert agents are not identical.

Abstract: A turbine inlet temperature operating section (15) determines the turbine inlet temperature T4 based on the flow rate Gf and temperature Tf of fuel being supplied to a combustor (3) and the flow rate G3 and temperature T3 of air. Based on the turbine inlet temperature T4, a pilot ratio operating section (16) sets a pilot ratio, and a bypass valve operating section (17) and an IGV opening operating section (18) generate a bypass valve control signal and an IGV control signal, respectively.

Abstract: The gas turbines of the present invention have multiple combustion chambers, and within each chamber are multiple fuel nozzles. Each nozzle has its own fuel control valve to control the fuel flowing to the nozzles. To minimize the pressure drop through the fuel control valves, multiple manifolds are employed. Each manifold supplies at least one fuel nozzle in multiple combustion chambers with fuel. The fuel control valves are mounted on the manifolds such that the weight of the fuel control valves and nozzles are carried by the manifolds, not the multiple combustion chambers. A plurality of thermocouples for measuring exhaust gas from said multiple combustion chambers are employed to sense gas exhaust temperature. In carrying out the methods of the present invention for tuning a gas turbine, it is essential to note that the most efficient gas turbine is one which has the least nitrous oxides, the least amount of unburned hydrocarbons, and the least amount of carbon monoxide for a specified energy output.

Abstract: A single stage combustor for a gas turbine having an annular array of outer fuel nozzles arranged about a center axis of the combustor; a center fuel nozzle aligned with the center axis, wherein the center fuel nozzle is substantially smaller than each of the outer fuel nozzles, wherein the combustor includes a pre-mix operating mode in which the center nozzle receives a fuel rich air-fuel mixture.

Abstract: The invention relates to a device for passive control of the thermal expansion of the extension casing of a turbo-jet engine, said extension casing surrounding the casing of the high pressure compressor of the turbo-jet engine, and including a flange for attachment to an upstream flange of the casing of the combustion chamber. It is characterised in that at least one circumferential cavity is provided between both said flanges wherein circulates a gas flux tapped at the inlet of the combustion chamber. One uses thus a natural circulation generated by the differential pressure. Thanks to the device of the invention, the flange is passively controlled, and the stresses resulting from a differential expansion between the skin of the casing and its attachment flange are reduced.

Abstract: An apparatus for providing a backup fuel metering system for the gas generator section (24) of a gas turbine engine (10) is disclosed that includes a gas generator (24) and an augmentor (40). The apparatus includes a gas generator fuel metering system (52) providing fuel to the gas generator nozzles (32) and an augmentor fuel metering system (54) providing fuel to an augmentor (40). The augmentor fuel system (54) includes a diverter valve (88) which selectably directs fuel to the augmentor (40) during augmentation operation or to the gas generator nozzles (32) during a gas generator metering system failure or critical engine operation. The system allows the gas generator nozzles (32) to be supplied with fuel flow from the gas generator metering system (52), the augmentor metering (54) system or both. When the gas generator nozzles (32) are being supplied with flow from both metering systems the system is capable of improved fault accommodation.

Abstract: A method for combustion in a combustor in a gas turbine including: fueling the center fuel nozzle with a fuel-rich mixture of gaseous fuel and air and fueling the outer fuel nozzles with a fuel-lean mixture of fuel and air; igniting the fuel-rich mixture injected by the center fuel nozzle while the fuel-lean mixture injected by the outer combustors is insufficient to sustain ignition; stabilizing a flame on the center fuel nozzle using the bluff body and while the outer fuel nozzles inject the fuel-lean mixture; staging fuel to the outer nozzles by increasing a fuel ratio of the fuel-lean mixture, and after the outer nozzles sustain ignition, reducing fuel applied to the center nozzle.

Abstract: A replaceable section (25) of force-cooling tubing assembly (21, 22) for attachment to a transition piece (5) of a gas turbine is comprised of two ends (54, 70) fashioned for attachment by removable unions (52) to adjoining parts of a force-cooling tubing assembly. When assembled thereto to complete the assembly, the replaceable section 25 provides for fluid communication between a manifold (3) and the transition piece (5) for either the supply or return of cooling fluid. A transition piece (5) in combination with two such assemblies, one a supply assembly (21), the other a return assembly (22), comprises a field-installable transition piece assembly (10) that provides for rapid and easy installation.

Abstract: A gas turbine engine includes an interstage seal assembly positioned in a plenum between the compressor section and turbine section. The seal assembly includes an annular seal member positioned in the plenum adjacent to the compressor section for restraining a fluid flow between the compressor section and the turbine section, and an annular heat shield member positioned in the plenum adjacent to the turbine section for limiting heat transfer from the turbine section to the compressor section. The annular heat shield member includes a plurality of slots formed on a surface of the heat shield member in a radial direction of the annular heat shield member.

Abstract: Conventional auxiliary power units (APUs) may experience over-temperature shutdowns when attempting to start them at high altitudes. Further, such conventional APUs may also experience overspeed conditions when a generator load is removed during on-speed operations. A fuel control logic that controls the fuel flow cutback below the minimum blowout fuel schedule is provided. A temperature trim loop measures engine temperature to determine the onset of a possible over-temperature condition. The fuel flow may then be trimmed accordingly to correct this over-temperature onset. Further, when the onset of an overspeed condition is detected, such as when a generator load is removed, the fuel flow may be trimmed accordingly to correct this overspeed onset. The fuel control logic allows the control to find the individual minimum fuel flow for each fuel control without risking blowout of the APU itself.

Abstract: The present invention comprises a highly supercharged, regenerative gas-turbine system. The gas turbine comprises a compressor, a regenerator, a combustor, and an expander. A pre-compressor pressurizes air going into the compressor section of the gas turbine. A cooler lowers the temperature of the air going into the compressor. The compressor pressurizes air, which then flows through the regenerator, which heats the air before it enters the combustor. The combustor further heats the air which then flows through the expander and then the regenerator. A post-expander is preferably located downstream of the regenerator. The post-expander is a second expander that receives high-pressure gas exiting the regenerator. The post-expander preferably drives the pre-compressor. The preferred pre-compressor and post-expander are toroidal intersecting vane machines (TIVMs), which are positive-displacement rotary devices. Numerous alternated embodiments of this basic system are described.