Abstract: A flexible coupling arrangement includes an outer first member, an outer second member, and an outer flexible coupling. The outer flexible coupling is arranged to transmit torque between the outer first member and the outer second member while allowing at least one of angular misalignment and axial misalignment between the outer first member and the outer second member. The flexible coupling also includes an inner first member, an inner second member, and inner flexible coupling. The inner flexible coupling arranged to transmit torque between the inner first member and the inner second member while allowing at least one of angular misalignment and axial misalignment between the inner first member and the inner second member. The inner flexible coupling is positioned radially inward of the outer flexible coupling.

Abstract: A flexible diaphragm coupling that includes a primary torque path and a secondary torque path. The secondary torque path includes a crowned or spherical spline assembly and provides additional capability during transient overtorque of the primary torque path or acts as the primary torque path in the unlikely event of diaphragm failure.

Abstract: A flexible coupling arrangement includes an outer first member, an outer second member, and an outer flexible coupling. The outer flexible coupling is arranged to transmit torque between the outer first member and the outer second member while allowing at least one of angular misalignment and axial misalignment between the outer first member and the outer second member. The flexible coupling also includes an inner first member, an inner second member, and inner flexible coupling. The inner flexible coupling arranged to transmit torque between the inner first member and the inner second member while allowing at least one of angular misalignment and axial misalignment between the inner first member and the inner second member. The inner flexible coupling is positioned radially inward of the outer flexible coupling.

Abstract: A fuel injector for a gas turbine engine is disclosed which includes a nozzle body for issuing fuel and air into a combustor, and an on-axis optical probe located within the nozzle body for observing combustor flame radiation, wherein the optical probe includes a plurality of optical fiber bundles extending to a distal end of the probe, and a shaped lens is supported at the distal end of the probe to provide a multi-directional field of view of combustion characteristics and properties in an operating gas turbine engine combustor.

Abstract: A trim valve includes a valve housing having an inlet section and an outlet section. A valve shaft is mounted to the valve housing to be stationary with respect thereto. The valve shaft includes an internal flow passage in fluid communication with the outlet section of the valve housing. A valve rotor is disposed inboard of the valve housing and outboard of the valve shaft for modulating flow through the valve housing. The valve rotor is mounted for rotational movement within the valve housing between a fully open position in which a flow path is defined between the inlet and outlet sections of the valve housing, and a reduced flow position in which the valve rotor at least partially blocks the flow path. An actuator is operatively connected to the valve housing to actuate the valve rotor between the fully open and reduced flow positions.

Abstract: A method of actively controlling pattern factor in a gas turbine engine includes the steps of issuing fuel into a combustion chamber of a gas turbine engine through one or more circumferentially disposed fuel injectors, determining an initial circumferential pattern factor in the combustion chamber, and adjusting fuel flow through one or more selected fuel injectors based on the initial circumferential pattern factor, to yield a modified circumferential pattern factor in the combustion chamber. The step of determining the circumferential pattern factor can include the steps of detecting a chemiluminescent signature within the combustor, correlating the chemiluminescent signature to an equivalence ratio, and computing the initial circumferential pattern factor based on the equivalence ratio.

Abstract: A method of actively controlling pattern factor in a gas turbine engine includes the steps of issuing fuel into a combustion chamber of a gas turbine engine through one or more circumferentially disposed fuel injectors, determining an initial circumferential pattern factor in the combustion chamber, and adjusting fuel flow through one or more selected fuel injectors based on the initial circumferential pattern factor, to yield a modified circumferential pattern factor in the combustion chamber. The step of determining the circumferential pattern factor can include the steps of detecting a chemiluminescent signature within the combustor, correlating the chemiluminescent signature to an equivalence ratio, and computing the initial circumferential pattern factor based on the equivalence ratio.

Abstract: A method of actively controlling pattern factor in a gas turbine engine includes the steps of issuing fuel into a combustion chamber of a gas turbine engine through one or more circumferentially disposed fuel injectors, determining an initial circumferential pattern factor in the combustion chamber, and adjusting fuel flow through one or more selected fuel injectors based on the initial circumferential pattern factor, to yield a modified circumferential pattern factor in the combustion chamber. The step of determining the circumferential pattern factor can include the steps of detecting a chemiluminescent signature within the combustor, correlating the chemiluminescent signature to an equivalence ratio, and computing the initial circumferential pattern factor based on the equivalence ratio.

Abstract: Methods of managing fuel temperatures in fuel injectors for gas turbine engines include cooling fuel circuits by initiating fuel flow therethrough using opened, closed, and semi-open control techniques. A fuel injector for a gas turbine engine includes a feed arm having a fuel inlet fitting for delivering fuel to at least one fuel conduit extending through the feed arm. A nozzle body depends from the feed arm and has at least one fuel circuit extending therethrough. The fuel circuit is configured and adapted to receive fuel from the feed arm and to issue fuel from an exit orifice of the nozzle body. Sensing means are provided adjacent to the at least one fuel circuit. The sensing means are configured and adapted to provide temperature feedback in order to control fuel flow in the at least one fuel circuit to maintain fuel temperature within a predetermined range.

Abstract: Methods of managing fuel temperatures in fuel injectors for gas turbine engines include cooling fuel circuits by initiating fuel flow therethrough using opened, closed, and semi-open control techniques. A fuel injector for a gas turbine engine includes a feed arm having a fuel inlet fitting for delivering fuel to at least one fuel conduit extending through the feed arm. A nozzle body depends from the feed arm and has at least one fuel circuit extending therethrough. The fuel circuit is configured and adapted to receive fuel from the feed arm and to issue fuel from an exit orifice of the nozzle body. Sensing means are provided adjacent to the at least one fuel circuit. The sensing means are configured and adapted to provide temperature feedback in order to control fuel flow in the at least one fuel circuit to maintain fuel temperature within a predetermined range.

Abstract: A trim valve includes a valve housing having an inlet section and an outlet section. A valve shaft is mounted to the valve housing to be stationary with respect thereto. The valve shaft includes an internal flow passage in fluid communication with the outlet section of the valve housing. A valve rotor is disposed inboard of the valve housing and outboard of the valve shaft for modulating flow through the valve housing. The valve rotor is mounted for rotational movement within the valve housing between a fully open position in which a flow path is defined between the inlet and outlet sections of the valve housing, and a reduced flow position in which the valve rotor at least partially blocks the flow path. An actuator is operatively connected to the valve housing to actuate the valve rotor between the fully open and reduced flow positions.

Abstract: A system is disclosed for actively controlling combustion in a gas turbine engine, which includes a fuel injector for issuing fuel into a combustion chamber of the gas turbine engine. The fuel injector has a dynamic pressure sensor for measuring acoustic pressure within the combustion chamber and a flame sensor for observing flame characteristics within the combustion chamber. The system further includes a high speed valve assembly for controlling flow of fuel to the injector and an electronic controller associated with the fuel injector for commanding the valve assembly to deliver fuel to the fuel injector at a commanded flow rate, based upon input from the sensors in the fuel injector.

Abstract: Methods of managing fuel temperatures in fuel injectors for gas turbine engines include cooling fuel circuits by initiating fuel flow therethrough using opened, closed, and semi-open control techniques. A fuel injector for a gas turbine engine includes a feed arm having a fuel inlet fitting for delivering fuel to at least one fuel conduit extending through the feed arm. A nozzle body depends from the feed arm and has at least one fuel circuit extending therethrough. The fuel circuit is configured and adapted to receive fuel from the feed arm and to issue fuel from an exit orifice of the nozzle body. Sensing means are provided adjacent to the at least one fuel circuit. The sensing means are configured and adapted to provide temperature feedback in order to control fuel flow in the at least one fuel circuit to maintain fuel temperature within a predetermined range.

Abstract: A valve assembly is disclosed for modulating the flow of fuel to a fuel nozzle at a high frequency or in a stepped manner to actively control combustion in a gas turbine engine which includes a valve housing defining an inlet portion for receiving fuel from a fuel source at an initial flow rate and an outlet portion for delivering fuel to a fuel nozzle at the initial flow rate or a modulated flow rate depending upon a detected combustion condition, and a mechanism disposed within the valve housing for modulating the flow rate of fuel to the outlet portion in response to a detected combustion condition.

Abstract: Valve systems for controlling a flow of fuel in a gas turbine engine and related methods are provided. In one embodiment, the valve system includes a supply conduit, a proportional valve portion, and a pulsating valve portion. The supply conduit is adapted and configured for receiving and carrying a flow of fuel. The proportional valve portion is in fluid connection with the supply conduit adapted and configured to gradually adjust a pressure drop thereacross and thus a flow rate of fuel flowing therethrough. The pulsating valve portion is in fluid connection with the supply conduit, in parallel with the proportional valve portion, and is adapted and configured to rapidly adjust a pressure drop thereacross and thus a flow rate of fuel flowing therethrough.

Abstract: A method of actively controlling pattern factor in a gas turbine engine includes the steps of issuing fuel into a combustion chamber of a gas turbine engine through one or more circumferentially disposed fuel injectors, determining an initial circumferential pattern factor in the combustion chamber, and adjusting fuel flow through one or more selected fuel injectors based on the initial circumferential pattern factor, to yield a modified circumferential pattern factor in the combustion chamber. The step of determining the circumferential pattern factor can include the steps of detecting a chemiluminescent signature within the combustor, correlating the chemiluminescent signature to an equivalence ratio, and computing the initial circumferential pattern factor based on the equivalence ratio.

Abstract: A method of controlling combustion stability in a turbine engine having combustion stability control capability includes the steps of providing at least one pair of pulsating valves, mutually arranged in parallel with respect to fuel flow provided to a combustor of the turbine engine, detecting an amplitude and frequency of a pressure wave of at least one periodic combustion instability, selecting an amplitude, frequency and first phase shift, with respect to the pressure wave, of resultant fuel pulsations to reduce the amplitude of the pressure wave, translating the selected amplitude into a second, relative phase shift between each pulsating valve of at least one pair of pulsating valves, and commanding each pulsating valve of at least one pair of pulsating valves to operate at the selected frequency and a relative second phase shift with respect to one another, to yield a resultant fuel pulsation at the selected amplitude, frequency and first phase shift, with respect to the detected pressure wave of combu

Abstract: A valve assembly for modulating fuel flow is disclosed which includes a valve housing having an inlet section and an outlet section, at least one valve rotor disposed between the inlet section and the outlet section for modulating fuel flow through the valve housing, wherein the at least one valve rotor is formed from a ferritic magnetic flux permeable material and is mounted for rotational movement within the valve housing, under the influence of a torsion spring, between first and second magnetically latched positions, and a pair of electromagnets means for alternately latching the at least one valve rotor in the first and second magnetically latched positions.