Abstract: A method for quickly stopping the propulsion rotor of a helicopter after landing, comprising, following a request for quickly stopping the engine by a helicopter pilot, the following steps managed by the control unit of the turbomachine: Detecting the absence of the thermal stabilization phase of the gas generator of at least one turbomachine, controlling an extinction of the combustion chamber of the gas generator of at least one turbomachine, maintaining the rotation of the gas generator of which the combustion chamber is extinguished by means of said at least one electrical machine to ventilate the gas generator and stopping the main rotor of the helicopter by means of a mechanical brake.

Abstract: A combustion chamber for a turbomachine including an annular casing delimiting an inner volume of the combustion chamber and provided with a chimney extending to the outside of the inner volume and delimiting a passage for a penetrating part, and a bushing mounted floating on the chimney, further includes: a main air collection chamber open to the upstream arranged facing the downstream portion of the chimney; and a through-opening of the annular casing, connecting the inner volume to the main air collection chamber. The air collected by the main air collection chamber is injected into the inner volume via the through-opening and can cool an annular casing zone downstream of the chimney.

Abstract: A dome-deflector assembly for a gas turbine includes a dome, a deflector, and at least one dome-deflector connecting assembly that includes a connecting member connecting the dome and the deflector together with a cavity being defined between the dome and the deflector. The connecting member extends through the deflector and has a first end arranged at a hot surface side of the deflector and a second end arranged to connect with the dome. The dome-deflector connecting assembly is configured to provide a flow of cooling air from the cavity to the hot surface side of the deflector to cool the first end of the connecting member on the hot surface side of the deflector.

Abstract: A method of optimizing a premix fuel nozzle for a gas turbine is provided including the step of providing a nozzle that provides, when the gas turbine is in operation, an axial flow field of an air and fuel mixture flows through the burner tube and around the nozzle tip, and at least two recirculation zones with at least two differing radial extents as part of a toroidal vortex generated on the nozzle tip to provide strong flame holding and flame propagation.

Abstract: A rectifying device includes an air flow generator. The air flow generator is disposed at an exterior member of a vehicle. The exterior member is adjacent to a detector of a sensor that is disposed such that at least a portion of a detection range of the detector includes a rear region behind a plane in a traveling direction of the vehicle. The plane is parallel to a width direction and a vertical direction of the vehicle. The air flow generator is configured to generate an air flow that separates, from the detector of the sensor, travelling wind that accompanies travel of the vehicle. The air flow generator includes a plasma actuator that includes at least a pair of electrodes and a power source that is configured to apply an alternating current voltage to the electrodes.

Abstract: An apparatus generates energetic particles and generates a plasma of a vaporized solid material and gaseous precursors for the application of coatings to surfaces of a substrate by way of condensation of plasma and for electric propulsion applications.

Abstract: A turbine engine can include a compressor section, a combustion section, and a turbine section in serial flow arrangement. The combustion section can have a combustor with a combustor liner at least partially defining a combustion chamber, as well as a fuel-air mixer including at least one set of mixing tubes.

Abstract: According to certain aspects, an electric-propulsion thruster is used as part of a base or platform which also includes a power converter, having a plurality of inductors and other electrical components, and a printed circuit board (PCB). The PCB includes a layer at which the other electrical components and printed circuit inductor traces, for the plurality of inductors, are secured. The electric-propulsion thruster includes a housing (e.g., as part of the base or platform) providing a cavity and having at least one structurally-rigid side wall along the cavity, where the PCB is integrated with the electric-propulsion thruster for a compact arrangement which can be used to propel the apparatus. Such a compact design might be used as an important part of thruster spacecraft architecture such as micro-satellites (e.g., CubeSats).

Abstract: The present disclosure provides methods and systems for determining a synthesized engine parameter of a gas turbine engine. An initial model parameter is obtained from an onboard model associated with the gas turbine engine. A correction factor for the onboard model is determined by modifying a difference between the onboard model and an aero-thermal model of the gas turbine engine using first and second engine parameters and first and second operating conditions, wherein the first and second engine parameters are independent from one another over an operating envelope of the gas turbine engine. The initial model parameter is scaled by applying the correction factor thereto to obtain a corrected model parameter. The corrected model parameter is output as the synthesized engine parameter.

Abstract: A combustion chamber, in particular for a gas turbine, includes a support structure, a plurality of retaining elements fastened to the support structure, and a plurality of heat shield elements which jointly form a heat shield and which each have a hot gas side, a cold gas side and end faces which interconnect the hot gas side and the cold gas side, the retaining elements interlockingly engaging in recesses in the heat shield elements. The retaining elements each have at least two engagement portions for interlockingly engaging in the recesses in a heat shield element, which engagement portions are interconnected in a tensionally rigid manner and are tensionally rigid themselves. Spring elements extend between the support structure and the heat shield elements, which spring elements are designed in particular as leaf springs and effect a frictional connection between the engagement portions of the retaining elements and the heat shield elements.

Abstract: The present disclosure relates to a system for supplying fuel to a turbomachine. In some embodiments, the system includes a pump, a hydromechanical group, a drive device positioned to drive the pump, and a branch comprising actuators for controlling variable geometry. In some embodiments, the system regulates a fuel flow rate based at least in part on a flow rate set point value. In some embodiments, the system may include a flow rate sensor. A flow rate loop may be arranged to determine a pressure set point value at the outlet of the pump according to the flow rate set point value and a measurement supplied by the flow rate sensor. In some embodiments, a pressure sensor may be positioned in the fuel circuit at the outlet of the pump. In further embodiments, a pressure loop may control the speed of the drive device based at least on a difference between a pressure measurement supplied by the pressure sensor and the pressure set point value.

Abstract: Scalable power processing units (PPUs) for Hall-effect thrusters (HETs) and terrestrial systems are disclosed. A technique for current estimation may be employed on each output of parallel isolated discharge supply modules (DSMs) to force proper current/load sharing between the DSMs. A flyback power supply may be used that performs the dual functions of a cathode keeper plasma ignitor and sustainer. The flyback power supply may be tuned for a high no-load direct current (DC) output voltage to achieve cathode keeper ignition rather than requiring a separate ignitor supply, which reduces circuit complexity. To address requirements for higher voltage DC ignition than are achievable with a flyback power supply alone, a supplemental DC ignitor may be placed in parallel with the flyback power supply of some embodiments. Such simplified PPU architectures may provide a high efficiency, low part count, scalable architecture suitable for more compact and lower cost system designs.

Abstract: A fuel nozzle for a combustor may include a primary fuel passage having a primary fuel outlet. A secondary fuel passage having a secondary fuel outlet. A valve located within the secondary fuel passage. The valve may include a stationary hub having a plurality of first angled surfaces. The valve may include a movable sleeve having a plurality of second angled surfaces. Each of the plurality of first angled surfaces aligns axially with a respective one of the plurality of second angled surfaces to define a slot therebetween. The valve is movable between a plurality of positions to open, to close, or to partially open the slots.

Abstract: A gas turbine engine includes a fan shaft diving a fan having fan blades. A gear system includes a sun gear surrounded by a plurality of intermediate gears. A carrier at least partially supports the plurality of intermediate gears. A ring gear surrounds the plurality of intermediate gears. The sun gear is driven by a turbine. At least one fan shaft support bearing is located forward of the gear system. A coupling fixes the ring gear from rotation relative to an engine static structure. A lubrication system lubricates components across a rotation gap. The lubrication system includes a lubricant input. A stationary first bearing receives lubricant from the lubricant input and has a first race in which lubricant flows. A second bearing rotates within the first bearing. The second bearing has a first opening in registration with the first race such that lubricant may flow from the first race through the first opening into a first conduit.

Abstract: A gas turbine engine includes a propulsor with a power turbine, a power turbine shaft extending forward therefrom defining a centerline axis, and a fan driven by the power turbine shaft. The fan is aligned with the centerline axis forward of the power turbine and is operatively connected to be driven by the power turbine through the power turbine shaft. A gas generator operatively connected to the propulsor is included downstream from the fan and forward of the power turbine, wherein the gas generator defines a generator axis offset from the centerline axis. The gas generator is operatively connected to the power turbine to supply combustion products for driving the power turbine.

Abstract: A field emission propulsion system for a spacecraft includes a control unit, a propulsion assembly, and a plurality of extractor electrode voltage sources. The propulsion assembly comprises a plurality of field emission propulsion units having an ion source with a plurality of ion emitters and extractor electrodes associated with the ion emitters and disposed in a field arrangement. The plurality of extractor electrode voltage sources, each associated with the extractor electrodes to control the same, are controlled by the control unit using an individual extractor electrode voltage.

Abstract: Disclosed is a closed drift, narrow channel Hall thruster configured to operate at powers <30 W. The thruster includes a thruster body and a neutralizing cathode. The thruster body includes a magnetic circuit including a magnetic source and two magnetic poles, a metallic, annular thruster channel formed by the magnetic poles with a downstream channel width smaller than about 3 mm and an upstream channel width greater than the downstream channel width, an anode positioned at the channel's entry, and a gas distributor configured to release a propellant gas into the thruster channel. The magnetic circuit is configured to generate a magnetic field in the thruster channel for trapping electrons therein. The channel walls (the magnetic poles) are under bias potential. The anode and the cathode are configured to generate a substantially axial electric field in the thruster channel.

Abstract: A controller may use energy packets to control a prime mover of a machine. The controller may include an energy packet measurement control to calculate energy packets, perform post-processing actions on the energy packets to generate processed energy packets, and convert the processed energy packets into a fuel valve reference. Post-processing may include a calibration correction to remove measurement artifacts.

Abstract: A gas turbine includes: multiple fuel systems; a combustor that combusts fuels from the multiple fuel systems in compressed air to generate combustion gas; and a turbine that is driven by the combustion gas. A flow volume ratio calculation device which calculates the flow volume ratio of the fuels flowing in the multiple fuel systems includes calculators that receive values of a first parameter and a second parameter capable of expressing the combustion state in the combustor, and that calculate the flow volume ratio relative to the received values of the two parameters from a predetermined relationship between the two parameters and the flow volume ratio.

Abstract: Systems and method for filling a fuel manifold comprising at least a primary and a second manifold of a gas turbine engine are described. The method comprises providing fuel flow to the secondary manifold of the gas turbine engine, the secondary manifold being partly or completely empty; monitoring at least one engine operational parameter of the gas turbine engine as fuel fills the secondary manifold; and accelerating the engine when a transition threshold is reached, the transition threshold being associated with the engine operational parameter and indicative that fuel has reached the combustor.