Abstract: A system and method for operating a combustion system comprising a fuel nozzle defining at least one main fuel circuit and at least one pilot fuel circuit is generally provided. The method includes determining an overall flow of fuel, the overall flow of fuel defining a sum total fuel through the main fuel circuit and the pilot fuel circuit; determining a plurality of ranges of ratios of main fuel flow through the main fuel circuit versus pilot fuel flow through the pilot circuit from the overall flow of fuel, wherein each range of ratios is based on a combustion criterion different from one another; determining a resultant range of ratios of main fuel flow versus pilot fuel flow based on a hierarchy of combustion criteria, wherein the hierarchy of combustion criteria provides a priority ranking of the combustion criterion; and flowing the overall flow of fuel to the main fuel circuit and the pilot fuel circuit based on the resultant range of ratios of main fuel flow versus pilot fuel flow.

Abstract: A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.

Abstract: A propulsion system includes a fan, a gear, a turbine configured to drive the gear to, in turn, drive the fan. The turbine has an exit point, and a diameter (Dt) is defined at the exit point. A nacelle surrounds a core engine housing. The fan is configured to deliver air into a bypass duct defined between the nacelle and the core engine housing. A core engine exhaust nozzle is provided downstream of the exit point. A downstream most point of the core engine exhaust nozzle is defined at a distance from the exit point. A ratio of the distance to the diameter is greater than or equal to about 0.90.

Abstract: A gas turbine engine component assembly comprising: a first component having a first surface and a second surface opposite the first surface, wherein the first component includes a cooling hole extending from the second surface to the first surface; a second component having a first surface and a second surface, the first surface of the first component and the second surface of the second component defining a cooling channel therebetween; and a lateral flow injection feature integrally formed in the first component and fluidly connecting a flow path located proximate to the second surface of first component to the cooling channel, the lateral flow injection feature being configured to direct airflow from the airflow path through a passageway and into the cooling channel at least partially in a lateral direction parallel to the second surface of the second component such that a cross flow is generated in the cooling channel.

Abstract: An assembly is provided for a gas turbine engine. This assembly includes a combustor wall, a case and an inlet. The combustor wall is configured with a quench aperture. The case is displaced from the combustor wall such that a plenum is formed by and extends between the combustor wall and the case. The case includes a case wall, a deflector and a conduit. The deflector projects out from the case wall into the plenum towards the combustor wall. The deflector is arranged upstream of the quench aperture. The inlet to the conduit is arranged next to and downstream of the deflector.

Abstract: An integrated combustor nozzle includes a combustion liner that extends radially between an inner liner segment and an outer liner segment. The combustion liner includes a forward end portion, an aft end portion, a first side wall, and a second side wall. The aft end portion of the combustion liner defines a turbine nozzle. The integrated combustor nozzle further includes an impingement panel having an impingement plate disposed along an exterior surface of one of the inner liner segment or the outer liner segment. The impingement plate defines a plurality of impingement holes that direct coolant in discrete jets towards the exterior surface of the inner liner segment or the outer liner segment. The impingement panel is radially spaced from the exterior surface to form a cooling flow gap therebetween. The impingement panel includes a collection duct that extends from the impingement panel and defines a collection passage.

Abstract: A turbomachine includes a compressor and a turbine with a burner and a combustor between the compressor and the turbine. The burner is downstream of the compressor and upstream of the turbine. The burner is connected to the combustor at a front panel of the burner. The front panel includes a frame, a rim extending around a central aperture within the frame, and a seal segment. The frame, the rim, and the seal segment are all integrally formed as a single unitary body.

Abstract: A pilot burner assembly for a combustion volume in a gas turbine engine includes a pilot burner, a pilot-fuel supply line, and a pilot-air supply line. The pilot burner has a burner face that includes a plurality of pilot-fuel injection holes. The pilot-fuel injection holes provide a pilot-fuel to the combustion volume. The pilot-fuel supply line is fluidly connected to the pilot-fuel injection holes for supplying the pilot-fuel to the pilot-fuel injection holes. The pilot-air supply line provides a pilot-air to the pilot burner. The pilot-air is supplied to the combustion volume through the burner face. Pilot-air injection holes are located on the burner face and fluidly connected to the pilot-air supply line. The pilot-air injection holes inject the pilot-air into the combustion volume. A gas turbine has the pilot burner assembly.

Abstract: Electrical power generation system for an aircraft, including: a gas turbine having a high-pressure shaft and outputting a gas flow to actuate a free turbine, a polyphase permanent magnet generator coupled to the gas turbine and able to output a first alternating voltage for supplying through first conversion means a primary power supply network of the aircraft, the free turbine and the permanent magnet generator being mounted on the same drive shaft concentric with the high-pressure shaft of the gas turbine, a starter mounted on the high-pressure shaft able to ensure the starting of the gas turbine, the starter being a permanent magnet starter/generator able to output a second alternating voltage for supplying a secondary power supply network of the aircraft and auxiliary equipment of the gas turbine and the first conversion means include two first AC/DC converters controlled from a management unit.

Abstract: A plasma propulsion system with no internal electrodes is described. Gas is flowed into an insulated axisymmetric plasma liner. A radio frequency antenna generates an inductive or helicon plasma discharge within the liner. The plasma is accelerated through a converging/diverging magnetic field out of the liner, generating thrust.

Abstract: The present invention relates to an ion thruster for propulsion of spacecrafts, including: a reservoir for a propellant, an emitter for emitting ions of the propellant, the emitter having one or more projections of porous material and a base with a first side supporting said projections and a second side connected to the reservoir, and an extractor facing the emitter for extracting and accelerating the ions from the emitter, wherein the base is impermeable to the propellant at least on said first side and has pores or channels for providing flow of propellant from the reservoir to said projections.

Abstract: The present invention relates to electrospray thrusters, processes of making electrospray thrusters, and methods of using such electrospray thrusters. Applicant's thruster incorporates a unique geometry for the emitters and extractor grid that effectively eliminates ion interception on the grid, which is the primary failure mechanism of current devices, yet maintains the electric field conditions necessary for ion emission to occur. Without grid impingement, the thrust produced by the thruster is increased and thruster operational lifetime is increased substantially. Additionally, this non-traditional geometry also allows for higher electric fields at the emitter tip for a given applied voltage, thus enabling lower operational voltage of the thruster as compared to conventional designs.

Abstract: A gas turbine engine component assembly is provided. The gas turbine engine component assembly comprising: a first component having a first surface and a second surface; a threaded stud including a first end and a second end opposite the first end, the threaded stud extending from the second surface of the first component; and a faired body operably secured to the threaded stud, wherein the faired body is shaped to redirect the airflow in a lateral direction parallel to the second surface of the first component such that a cross flow is generated.

Abstract: A Hall effect thruster is provided having one or more components fabricated using additive manufacturing techniques. Additive manufacturing can be used to fabricate the propellant distributor and the discharge channel of the thruster. The propellant distributor can be separated from the anode of the thruster and can form the base of the discharge channel. The discharge channel can be detachably connected to the propellant distributor using one of a threaded connection or a snap-fit connection. The discharge channel can have an annular shape and electromagnets and magnetic poles can be placed in the surrounding areas of the discharge channel.

Abstract: Propulsion systems, such as electrospray thrusters, may include an electrically actuated valve to permit a selective flow of propellant to a thruster. The valve may be located and arranged such that it physically separates a propellant, such as a source of ions, from a thruster of the propulsion system. In some embodiments, the application of a voltage potential to the valve may wet a plurality of through holes formed in the valve with the propellant such that the propellant flows through the valve to the thruster. After the valve has been opened, the propulsion system may be operated normally.

Abstract: A system and method for supplying compressed air from an auxiliary power unit to a main engine starter motor. The inlet guide vanes are controlled using either first or second inlet guide vane control logic and the surge control valve is controlled using either first or second surge control valve control logic. When the first inlet guide vane control logic is used, the inlet guide vanes are positioned based on a demand signal, when the second inlet guide vane control logic is used, the inlet guide vanes are positioned based on a demand schedule, when the first surge control valve logic is used, the surge control valve can be commanded to repeatedly move to only a fully-closed position and a fully-open position, and when the second surge control valve logic is used, the surge control valve can be commanded to the fully-closed position only when maximum flow is commanded.

Abstract: A magnetic nozzle having a converging/diverging contour shape that converts the thermal energy of a propellant into directed kinetic energy, but uses magnetic fields instead of a physical boundary to direct the flow of particles.

Abstract: The first solid propellant is formed to have a columnar shape so as for a combustion surface to move to a first direction, and to have an end surface exposed to a combustion space. The surface of first solid propellant except for the end surface is covered with a barrier membrane. The position of combustion surface in the first direction is detected by a position sensor device in an always-on measurement or a fixed-point measurement. Based on the detected result, the consumption amount of the first solid propellant is estimated.

Abstract: The disclosure describes a system that includes an engine having a shaft that rotates around an axis of rotation, an engine controller configured to control the engine, an electric machine mechanically coupled to the shaft of the engine, and an electrical controller. The engine controller is configured to control the engine using control techniques configured for a mechanical device having a target moment of inertia around the axis of rotation. The electric machine has an actual moment of inertia around the axis of rotation that is different from the target moment of inertia. To supplement control of the engine due to the difference in moments of inertia, the electrical controller is configured to receive a rotational speed of the shaft, determine a torque for the shaft based on the speed of the shaft, and control the electric machine to apply the torque to the shaft.

Abstract: A signal processing apparatus includes a CPU which executes an input step of receiving an input of a measurement value of a target parameter at a first time, in which noise is superimposed on a true value of the target parameter, a calculation step of calculating a variation amount of the measurement value of the target parameter at the first time, based on a maximum likelihood estimate of the target parameter at a second time and calculating a maximum likelihood estimate of the variation amount, and an output step of outputting a value obtained by adding the maximum likelihood estimate of the variation amount to the maximum likelihood estimate of the target parameter at the second time, as a maximum likelihood estimate of the target parameter at the first time.