Abstract: A gas turbine engine includes a bypass duct including an outer wall, a heat exchanger arranged within the bypass duct, and a turnbuckle assembly. The outer wall includes a main body and an access panel removably coupled to the main body. The turnbuckle assembly couples the heat exchanger to the access panel, and includes a first rod coupled to the access panel and a second rod coupled to the first rod and to the heat exchanger. The outer end of the first rod is threadably received in a socket of a socket housing removably coupled to the access panel such that the first rod is fixedly coupled to the socket housing to increase lateral stiffness of the heat exchanger and the turnbuckle assembly such that the lateral dynamic mode is outside of a fan rotor operating range.

Abstract: An example system includes one or more heaters configured and positioned to add thermal energy to one or more portions of a gas turbine engine after the gas turbine engine was in operation, wherein the thermal energy minimizes or prevents undesired contact or seizing of a rotor of the gas turbine engine with another component of the gas turbine engine due to warping of the rotor due to uneven cooling of the gas turbine engine after the operation. The system further includes a controller configured to control operation of the one or more heaters.

Abstract: A propulsion unit includes a gas turbine engine and an exhaust nozzle coupled to an aft end of the gas turbine engine. The exhaust nozzle is configured to interact with exhaust gases exiting the gas turbine engine in an aft direction. The exhaust nozzle includes an outer nozzle case and an inner plug that cooperate to define an exhaust flow path therebetween. The exhaust nozzle is configured to manipulate the exhaust gases to provide different thrust capabilities for the gas turbine engine.

Abstract: An article may include a substrate, such as a silicon-containing ceramic matrix composite, an environmental barrier coating (EBC) layer on the substrate, and a CMAS-resistant EBC layer on the EBC layer. The EBC layer may include at least one rare-earth disilicate (REDS). The CMAS-resistant EBC layer may include at least one rare-earth monosilicate (REMS) configured to react with CMAS to form crystalline reaction products. The CMAS-resistant EBC layer may include a plurality of vertical cracks extending from a surface of the CMAS-resistant EBC layer at least partially into the CMAS-resistant EBC layer. Additionally, or alternatively, the EBC layer may include a plurality of vertical cracks extending from a surface of the EBC layer into at least a portion of the EBC layer.

Abstract: Various aspects of the techniques are directed to a turbine engine that includes a core section comprising a compressor and a turbine that both rotate about a longitudinal axis of the turbine engine. The turbine engine also includes a fan comprising radially distributed blades, the fan connected to the core section and configured to be rotated by the turbine, and an electrical generator integrated into the core vane assembly and positioned in the core section aft of the fan and fore of the at least one compressor. The electrical generator comprises a stator, a turbine configured to extract work from a core fluid flow, the turbine configured to rotate about the longitudinal axis, and a combined rotor rotationally coupled to the fan, the combined rotor formed from a single component that incorporates a blade retainer for retaining at least one of the plurality of radially distributed blades.

Abstract: A method of monitoring a health of a temperature system may comprise selecting a temperature sensor of a plurality of temperature sensors arranged in an array, where each temperature sensor corresponds to an address within the array. The method may comprise identifying the address corresponding to the single temperature sensor, sending the address to a multiplexer, and selecting the single temperature sensor using the identified address. The method may comprise testing the selected single temperature sensor calculating an average temperature detected by the plurality of temperatures sensors.

Abstract: A system for detecting a failure in a thermocouple array may comprise the thermocouple array. The thermocouple array may comprise a plurality of thermocouples. The system may comprise an impedance determination circuit. The impedance determination circuit may include a capacitor that has a capacitance equal to an expected capacitance of one of the plurality of thermocouples. The one of the plurality of thermocouples may be connected to test nodes of the impedance determination circuit. The system may comprise a comparator circuit connected to the impedance determination circuit, where the comparator circuit includes an amplifier and a comparator. The system may comprise an excitation circuit connected to the impedance determination circuit, where the excitation circuit includes a waveform generator and an amplifier.

Abstract: A gas turbine engine includes a fan and a fan case assembly. The fan includes a fan rotor configured to rotate about an axis of the gas turbine engine and a plurality of fan blades coupled to the fan rotor for rotation therewith. The fan case assembly extends circumferentially around the plurality of fan blades radially outward of the plurality of the fan blades.

Abstract: A method of assembling a radial turbine rotor includes manufacturing turbine blades, a flowpath ring, and a hub. The method includes fixing the turbine blades circumferentially around the flowpath ring by a blade joint between the turbine blades and the flowpath ring to form a ring assembly. The method includes spinning the hub and moving the hub into engagement with the flowpath ring to locate the hub radially inwardly of the flowpath ring and to form a hub joint between the flowpath ring and the hub.

Abstract: A gas turbine engine includes a heat exchanger and an inlet shroud. The heat exchanger is configured to transfer heat. The inlet shroud is configured to be coupled with the heat exchanger upstream of the heat exchanger.

Abstract: A fan case assembly extend along and around a center axis. The fan case assembly may comprise a barrel extending along and around the center axis, the barrel configured to fasten to a flange of an engine case. The fan case assembly may comprise a fan track liner disposed radially inward of the barrel and a containment hook, wherein the containment hook is a discrete component separate from the barrel. The containment hook may include a front segment configured to fasten to the flange, and an axial segment disposed radially inward of the barrel. The axial segment may extend between the flange and the fan track liner and the front segment may extend radially outward from an end of the axial segment. The containment hook may also include a protruding segment extending radially inward from the axial segment.

Abstract: A gas turbine engine includes a fan and a fan case assembly. The fan includes a fan rotor configured to rotate about an axis of the gas turbine engine and a plurality of fan blades coupled to the fan rotor for rotation therewith. The fan case assembly extends circumferentially around the plurality of fan blades radially outward of the plurality of the fan blades.

Abstract: A gas turbine engine includes a fan and a fan case assembly. The fan includes a fan rotor configured to rotate about an axis of the gas turbine engine and a plurality of fan blades coupled to the fan rotor for rotation therewith. The fan case assembly extends circumferentially around the plurality of fan blades radially outward of the plurality of the fan blades.

Abstract: A cooling apparatus includes a first fluid flowpath and a second fluid flowpath. The first fluid flowpath includes a subcooler having a first side in fluid communication with the first fluid flowpath; a flow control valve; a primary evaporator assembly including at least one evaporator configured to be disposed in thermal communication with a heat load; and a pressure regulator operable to control a saturation pressure within the at least one evaporator. The second fluid flowpath is in fluid communication with a second side of the subcooler.

Abstract: A gas turbine engine includes: an inlet guide vane; an inlet channel extending from a location downstream of the inlet guide vane to a stem manifold; and an outlet channel extending to an outlet port, the outlet port configured to dump anti-ice air overboard, wherein the inlet guide vane includes an anti-ice cavity in fluid communication with the inlet channel and the outlet channel such that anti-ice air, flowing from a downstream location within a core flow of the gas turbine, flows from the inlet channel, through the inlet guide vane, and to the outlet channel.

Abstract: A system includes a flow battery and a temperature control system. The flow battery is configured to thermally manage a thermal load. In some embodiments, the flow battery is also configured to electrically power the thermal load. The temperature control system is configured to cool electrolyte in the flow battery in response to the thermal load being inactive.

Abstract: A gas turbine engine includes a bypass duct, a heat exchanger, and an inlet shroud. The bypass duct is configured to direct air through a flow path. The heat exchanger is configured to receive a portion of the air flowing through the flow path of the bypass duct. The inlet shroud is coupled with the heat exchanger and configured to adjust a direction of the portion of the air entering the heat exchanger.

Abstract: A cooling system for an electronics cabinet includes a controller configured to operate at least one of a pump or a condenser of a two-phase cooling loop. The cooling system includes a high temperature mode where the setpoint is set to a high setpoint setting, and a low temperature mode where the setpoint is set to a low setpoint setting. The controller is configured to select between the high temperature mode and the low temperature mode based on an evaluation of a power outage.

Abstract: A heat exchanger may include a first coolant path for circulating a first coolant and a second coolant path for circulating a second coolant, where the first coolant path including a plurality of first cooling tubes, where the second coolant path including a plurality of second cooling tubes, where the first coolant path is fluidly isolated from the second coolant path in the heat exchanger, and where the first cooling tubes and the second cooling tubes are arranged in series and such that the first cooling tubes alternate with the second cooling tubes in an airflow direction.

Abstract: An infrared suppressor adapted for use with a gas turbine engine includes a first ring arranged circumferentially around a central axis, a second ring arranged circumferentially around the central axis, and a strut that extends radially between and interconnects the first ring and the second ring. A portion of the second ring extends radially toward the first ring such that the portion of the second ring cooperates with the first ring to block line-of-sight into the infrared suppressor.