Abstract: A gas turbine engine includes an outer case structure around a central longitudinal engine axis. An intermediate case structure is included inboard of the outer case structure. An inner case structure is included inboard of the intermediate case structure. A variable area exhaust mixer is included, which is movable between a closed position adjacent to the intermediate case structure and an open position adjacent to the inner case structure.

Abstract: A power generation system may include a generator, and a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow. A turbo-expander may also power the generator. A first control valve control flow of the excess air flow along an excess air flow path to an inlet of the turbo-expander. An educator may be positioned in the excess air flow path for using the excess air flow as a motive force to augment the excess air flow with additional air. A discharge of the turbo-expander is supplied to an inlet of the integral compressor.

Abstract: A Helmholtz damper for a combustor of a gas turbine includes an enclosure defining a damping volume from which a neck portion extends and which has a flow path (F) for cooling and purging air with an inlet opening and an outlet opening to the enclosure. The outlet opening is formed in the neck portion. A seal is arranged at the neck portion adjacent to the outlet opening for cooling and purging air such that a cooling effect of the seal is provided.

Abstract: Techniques for monitoring health of an igniter (202) in a gas turbine engine (201) include a sensor (270) mounted to detect signals in a combustor (260) and a processor (180) in electrical communication with the sensor. The processor is configured to receive (601) from the sensor first data that indicates signal changes in each of a plurality of time bins during operation of the igniter in the combustor. Information characteristics of the first data are determined (603). A value is determined (615) of a similarity measure that indicates similarity of the information characteristics to target information characteristics. Based on the value of the similarity measure, a condition of the igniter is determined (633) and a device is operated (635) based on the conditions, for example the condition is presented on a display (714).

Abstract: A gas turbine engine includes a first zone and a second zone downstream from the first zone. A buffer system can communicate a buffer cooling air to at least the first zone. A bleed source can communicate a bleed air to the second zone.

Abstract: A switching power converter is provided that extrapolates from a reference voltage during dead periods of a rectified input voltage as determined from a comparison of an Isense voltage to a current threshold.

Abstract: A switching regulator circuit incorporates an offset circuit, connected in a control loop of the regulator circuit, that, in response to a signal indicating an imminent load current step, adjusts a duty cycle of a power switch for the current step prior to the regulator circuit responding to a change in output voltage due to the current step. In one embodiment, a load controller issues a digital signal shortly before a load current step. The digital signal is decoded and converted to an analog offset signal in a feedback control loop of the regulator to immediately adjust a duty cycle of the switch irrespective of the output voltage level. By proper timing of the offset, output voltage ripple is greatly reduced. The current offset may also be used to rapidly change the output voltage in response to an external signal requesting a voltage step.

Abstract: A gas turbine engine includes a gear assembly and a bypass flow passage that includes an inlet and an outlet that define a design pressure ratio between 1.3 and 1.55. A fan is arranged at the inlet. A first turbine is coupled with a first shaft such that rotation of the first turbine will drive the fan, through the first shaft and the gear assembly, at a lower speed than the first shaft. The fan includes a row of fan blades. The row includes 12-16 (N) fan blades, a solidity value (R) that is from 1.0 to 1.3, and a ratio of N/R that is from 10.0 to 16.

Abstract: A switching shunt regulator circuit includes a current source having an input for receiving an input voltage and an output for providing a DC current, and a shunt voltage regulator coupled to the output of the current source. The current source is configured to provide DC current to a DC load and DC current to the shunt voltage regulator when the DC load is coupled to the output. The DC current to the shunt voltage regulator regulates a voltage at the output. The shunt voltage regulator has a current carrying capacity greater than the sum of the DC current to the DC load and the DC current to the shunt voltage regulator.

Abstract: A combined voltage regulator and snubber circuit generally has a voltage regulator device in parallel with the energy storage element of the snubber circuit operatively connectable in series with a leakage inductance current path; the leakage inductance being part of a magnetic component utilized in a switch-mode power supply having an input voltage source, controllable semiconductor switches, freewheeling semiconductor switches, feedback controller, reactive energy storage components and a load; the voltage regulator generally providing constant or variable voltage to the gate driver of the controllable semiconductor and/or feedback controller.

Abstract: A method for performing phase shedding for a voltage converter having a multi-phase output stage circuit includes: sensing an input current of the voltage converter to generate a first digital signal when enabling at least one first output stage within the multi-phase output stage circuit; sensing the input current of the voltage converter to generate a second digital signal when further enabling a second output stage within the multi-phase output stage circuit; comparing the first digital signal with the second digital signal to generate a comparison resultant signal; dynamically adjusting the phase shedding threshold according to the comparison resultant signal, to automatically search/determine an optimal phase shedding threshold; and, performing the phase shedding when an operation of the voltage converter exceeds the optimal phase shedding threshold.

Abstract: In a first period having a first period length, first data and second data are alternately given to an inverter control unit. The first data has a first value indicating a length of time from the start point of time of the first period to a matching point of time as a point of time when a converter carrier takes a converter threshold value and an inverter threshold value corresponding to a second period having the first value as its length. The second data has a second value indicating a length of time from the matching point of time to the end point of time of the first period and an inverter threshold value corresponding to a second period having the second value as its length.

Abstract: A gas turbine engine exhaust panel mounting system comprising a panel, a casing and an attachment assembly for removably connecting the panel to the casing comprises a retaining portion, a clamping portion, and a ‘C’-shaped connecting link. The connecting link has a first attachment portion and an opposite second attachment portion with the first and second attachment portions being connected to one another by a center portion. Each of the first and second attachment portions is substantially parallel to one another and extends in the same direction from respective ends of the center portion. The first attachment portion is fixedly connected to the casing by the clamping portion, and the second attachment portion is slidingly connected to the panel by the retaining portion.

Abstract: An apparatus includes a first substrate of a first material having a first bonding surface, and one or more fluidic channels open at a plane of the first bonding surface. The apparatus also includes a different second material disposed on the first substrate. The second material connects two different portions of the one or more fluidic channels. An outer surface of the second material is at the plane of the first bonding surface at positions between the two portions. The apparatus also includes a second substrate having a second bonding surface in contact with the first bonding surface, the second substrate configured to confine fluid flow within the one or more fluidic channels. In a Joule-Thompson cryocooler apparatus, the first material is a first thermally insulating material and the second material is a thermally conductive material and the second substrate is made of a second thermally insulating material.

Abstract: A gas-circulation system for conditioning a disk of an aircraft may comprise a first takeoff port configured to extract a combusted gas and a second takeoff port configured to extract an uncombusted gas. A first valve may comprise an inlet in fluid communication with the first and second takeoff ports and an outlet of the first valve in fluid communication with the disk.

Abstract: An object of the invention is to improve the cooling performance for a bus bar and a smoothing capacitor in an electric power converter. The electric power converter of the present invention includes a power semiconductor module including a power semiconductor element that converts a DC current to an AC current, a capacitor cell that smooths a DC voltage, a bus bar that electrically connects the power semiconductor module and the capacitor cell, a base plate that is disposed between the bus bar and the capacitor cell, and a sealing material that seals the capacitor cell, the bus bar, and the base plate. The base plate forms an opening through which a capacitor terminal extending from the capacitor cell passes.

Abstract: The feedback IC is provided at the secondary side of the DC/DC converter and is coupled to the photo coupler. The error amplifier amplifies an error between a voltage detection signal according to an output voltage of the DC/DC converter and a target voltage, and draws a current according to the error from the input side of the feedback photo coupler via the photo coupler connection terminal. The abnormal detection circuit asserts an abnormal detection signal when an abnormal condition in a secondary side of the DC/DC converter is detected. The protection circuit is coupled to the photo coupler connection terminal, and acts on the feedback photo coupler via the photo coupler connection terminal so that a feedback operation by the error amplifier is invalid and an on-period of the switching transistor is shorten.

Abstract: A gas turbine engine component includes a cooling hole. The component includes a first wall having an inlet, a second wall having an outlet and a metering section extending downstream from the inlet and having a substantially convex first surface and a substantially concave second surface. The component also includes a diffusing section extending from the metering section to the outlet. A gas turbine engine wall includes first and second surfaces and a cooling hole extending between an inlet at the first surface and an outlet at the second surface. The cooling hole includes a metering section commencing at the inlet and a diffusing section in communication with the metering section and terminating at the outlet. The metering section includes a top portion having a first arcuate surface and a bottom portion having a second arcuate surface. The first and second arcuate surfaces have arcs extending in substantially similar directions.

Abstract: A conventional single-ended, primary-inductance converter (SEPIC) has its switching frequency determined by a controller, which determines the duty cycle at which the switch operates by measuring differences between the SEPIC output voltage and a reference voltage. A controller is coupled to a switch of the SEPIC and provides a pulse train which determines the duty cycle and frequency at which the switch operates. The duty cycle is selectable between first and second percentages, the frequency is selectable between first and second frequencies, and the duty cycle and frequency are selected by the controller responsive to a voltage at an input voltage terminal of the SEPIC. Output voltage overshoot and undershoot are reduced.

Abstract: A gas turbine engine includes a first shaft coupled to a first turbine and a first compressor, a second shaft coupled to a second turbine and a second compressor, and a third shaft coupled to a third turbine and a fan assembly. The turbine engine includes a heat rejection heat exchanger configured to reject heat from a closed loop system with air passed from the fan assembly, and a combustor positioned to receive compressed air from the second compressor as a core stream. The closed-loop system includes the first, second, and third turbines and the first compressor and receives energy input from the combustor.