Abstract: A flexible coupling includes a flexure, a first drive member defining an axis and connected to the flexure, and a second drive member. The second drive member defines an axis and is connected to the flexure on a side of the flexure opposite the first drive member. An angular stop is fixed within the first drive member, extends through a portion of the second drive member, and is arranged to limit angular misalignment of the first drive member axis relative to the second drive member axis while transmitting torque between the first and second drive members.

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 includes a flexure, a first drive member defining an axis and connected to the flexure, and a second drive member. The second drive member defines an axis and is connected to the flexure on a side of the flexure opposite the first drive member. An angular stop is fixed within the first drive member, extends through a portion of the second drive member, and is arranged to limit angular misalignment of the first drive member axis relative to the second drive member axis while transmitting torque between the first and second drive members.

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: A method of combustion stability control for a gas turbine engine is provided, and includes the steps of receiving by a stability controller, information regarding environmental and operating conditions, and comparing the environmental and operating conditions to pre-programmed information to determine if a likelihood of combustion instability exists. The method further includes the steps of determining optimal fuel modulation frequency and amplitude for the environmental condition to reduce combustion instability, if a likelihood of combustion instability exists, and actuating at least one fuel modulation valve to, at the optimal fuel modulation frequency and amplitude, reduce combustion instability, if a likelihood of combustion instability exists. Systems for modulating fuel flow are also provided.

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.

Abstract: A method of combustion stability control for a gas turbine engine is provided, and includes the steps of receiving by a stability controller, information regarding environmental and operating conditions, and comparing the environmental and operating conditions to pre-programmed information to determine if a likelihood of combustion instability exists. The method further includes the steps of determining optimal fuel modulation frequency and amplitude for the environmental condition to reduce combustion instability, if a likelihood of combustion instability exists, and actuating at least one fuel modulation valve to, at the optimal fuel modulation frequency and amplitude, reduce combustion instability, if a likelihood of combustion instability exists. Systems for modulating fuel flow are also provided.