Abstract: A method for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: An apparatus for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: An apparatus for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: A gas turbine engine combustion system includes a plurality of fuel injectors circumferentially disposed around a combustor in a one to one fuel supply relationship with a plurality of fuel nozzle valves, and an electronic controller for controlling the fuel nozzle valves to eliminate and/or reduce hot streaking in response to sensed hot streak conditions. The fuel nozzle valves may be modulating valves. The electronic controller may be used to individually control the fuel nozzle valves. The hot streak conditions may be sensed with temperature sensors such as temperature sensors operably mounted in the combustor. A program in the electronic controller may be used for determining broken or malfunctioning sensors by calculating a combustor temperature and comparing it to measured temperatures from the sensors and comparing the measured fuel pressures in the individual fuel nozzle circuits with the simulated or calculated fuel pressures.

Abstract: An apparatus for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: A multi-staged gas turbine engine fuel supply system includes a plurality of fuel injectors and at least first and second staged fuel injection circuits in each of the fuel injectors. Each of the first and second staged fuel injection circuits includes first and second fuel injection points and at least first and second fuel nozzle valves operable to open at different first and second crack open pressures and controllably connected to the first and second staged fuel injection circuits, respectively. A single fuel supply manifold is connected to all of the fuel nozzle valves. A single fuel signal manifold is controllably connected to all of the first and second fuel nozzle valves. The fuel injector may have a valve housing with one of the first fuel nozzle valves and one of the second fuel nozzle valves contained therein.

Abstract: A multi-staged gas turbine engine fuel supply fuel injector includes at least first and second staged fuel injection circuits having first and second fuel injection points. At least first and second fuel nozzle valves operable to open at different first and second crack open pressures are controllably connected to the first and second staged fuel injection circuits, respectively. A single fuel supply manifold is connected to all of the fuel nozzle valves. A single fuel signal manifold is controllably connected to all of the first and second fuel nozzle valves. The fuel injector includes a valve housing containing the fuel nozzle valves.

Abstract: A method and system for monitoring the condition of a bearing mounted on a rotating shaft, particularly one present in an aircraft gas turbine engine, where the vibration sensor that monitors the bearing is remote therefrom but proximate to the rotating shaft. The vibration sensor obtains a broadband signal having frequencies that include the bearing defect peak of the monitored bearing. The broadband signal is analyzed to identify the presence of the bearing defect peak. If the bearing defect peak is present, the amplitude of this peak is quantified to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.

Abstract: A method and system for monitoring the condition of a bearing mounted on a rotating shaft, particularly one present in an aircraft gas turbine engine, where the vibration sensor that monitors the bearing is remote therefrom but proximate to the rotating shaft. The vibration sensor obtains a broadband signal having frequencies that include the bearing defect peak of the monitored bearing. The broadband signal is analyzed to identify the presence of the bearing defect peak. If the bearing defect peak is present, the amplitude of this peak is quantified to determine whether degradation of the monitored bearing has at least reached a threshold criteria previously established.