Abstract: Systems and methods are provided that use a tip clearance control apparatus comprising a mechanical iris, where the tip clearance control apparatus controls a distance between a tip of a blade and a ring of abradable material positioned in an adjustable opening of the mechanical iris.

Abstract: A turbine shroud assembly for use with a gas turbine engine includes a turbine outer case, a blade track segment, and a carrier. The turbine outer case is arranged circumferentially around an axis. The blade track segment includes an arcuate runner that extends circumferentially partway around the axis to define a gas path boundary of the turbine shroud assembly and an attachment feature that extends radially outward from the runner. The carrier is configured to couple the blade track segment to the turbine outer case.

Abstract: A combustor adapted for use in a gas turbine engine includes a metallic combustor shell forming an interior space, a heat shield, and a liner arranged in the interior space of the metallic case. The liner defines a combustion chamber in which fuel is burned during operation of a gas turbine engine.

Abstract: A gas turbine engine assembly includes adjacent components and a probe assembly. The probe assembly is configured to measure a distance between the probe assembly and blades located radially inward of the adjacent components.

Abstract: An example hybrid aircraft propulsion system includes one or more parallel propulsion units, each of the parallel propulsion units comprising: a first propulsor; a gas turbine engine configured to drive the first propulsor; and an electrical machine selectively configurable to: generate, for output via one or more electrical busses, electrical energy using mechanical energy derived from the first propulsor or the gas turbine engine; and drive the first propulsor using electrical energy received via the one or more electrical busses; and one or more series propulsion units, each of the series propulsion units comprising: a second propulsor; and an electrical machine selectively configurable to: generate, for output via the one or more electrical busses, electrical energy using mechanical energy derived from the second propulsor or the gas turbine engine; and drive the second propulsor using electrical energy received from one or more electrical busses.

Abstract: A turbine shroud assembly includes a carrier, a blade track segment, and an attachment pin. The carrier is arranged to extend circumferentially at least partway around an axis. The blade track segment includes a runner that faces the axis to define a portion of a primary gas path of the gas turbine engine and an attachment flange that extends radially away from the runner. The attachment pin is configured to mount the blade track segment to the carrier.

Abstract: A turbine shroud adapted for use in a gas turbine engine includes a seal segment and an attachment unit. The seal segment includes an arcuate shroud wall that extends circumferentially partway around an axis and a mount post that extends radially outward away from the shroud wall. The attachment unit includes a first carrier and a second carrier that cooperate to define a channel that receives at least a portion of the mount post.

Abstract: A turbine shroud assembly is adapted to extend around a turbine wheel mounted for rotation about a central reference axis of a gas turbine engine. The turbine shroud assembly includes a carrier segment made from metallic materials and a blade track segment made from ceramic matrix composite materials. The carrier extends at least partway about the axis. The blade track segment is supported by the carrier radially relative to the axis to define a portion of a gas path of the assembly.

Abstract: A turbine assembly adapted for use with a gas turbine engine includes an outer case, a blade track segment, and a carrier. The outer case extends circumferentially at least partway around an axis of the engine. The blade track segment is configured to define a portion of a gas path of the turbine assembly. The carrier is coupled with the outer case and the blade track segment to support the blade track segment in position radially relative to the axis. The carrier is coupled with the outer case for movement with the outer case in response to thermal expansion and contraction of the outer case during use of the turbine assembly.

Abstract: A cooling apparatus includes: a first fluid flowpath including the following elements, in downstream flow sequence: a separator vessel; a subcooler having a first side in fluid communication with the first fluid flowpath and a second side configured to be disposed in thermal communication with a cold sink; a flow control valve; a primary evaporator assembly including at least one primary evaporator configured to be disposed in thermal communication with a primary heat load; and a pressure regulator operable to maintain a refrigerant saturation pressure within the primary evaporator at a predetermined set point.

Abstract: Systems and methods to increase the recharge rate of a supplemental cooling system are provided. The system may include a primary cooling system configured to cool a thermal load, a supplemental cooling system, and a thermoelectric cooling apparatus. The thermoelectric cooling apparatus may assist the primary cooling system in recharging the supplemental cooling system in response to the supplemental cooling system operating in a recharge state, to the availability of electrical capacity, and to one or more operating parameters of the primary cooling system falling outside a predetermined range, wherein the operating parameter affects a cooling capacity of the primary cooling system.

Abstract: A microchannel heat exchanger (MCHX) includes an air-passage layer including a plurality of air-passage microchannels, a working fluid layer including a plurality of working fluid microchannels, and a sealing layer coupled to the working fluid layer to provide a working/sealing layer set. The working/sealing layer set includes an arrangement of raised pedestals. The raised pedestals may extend from the working fluid layer to the sealing layer and contact the sealing layer.

Abstract: A thermal management system for tightly controlling temperature of a thermal load (e.g., onboard an aircraft) includes: a pressurized tank for storing an expendable coolant; a control valve downstream of the pressurized tank for controlling a flow rate of the expendable coolant; a heat exchanger downstream of the control valve for transferring heat from a thermal load to the expendable coolant at a predetermined temperature; a back pressure regulator (BPR) downstream of the heat exchanger, the BPR having a set point controlled to maintain the expendable coolant at the predetermined temperature in the heat exchanger; optionally, a sensor or orifice downstream of the heat exchanger for determining vapor quality at an exit of the heat exchanger; and a system exit downstream of the BPR for removing some or all of the expendable coolant from the thermal management system after transferring heat from the thermal load to the expendable coolant.

Abstract: An assembly adapted for use in a gas turbine engine includes a carrier and a blade track segment. The carrier extends at least partway about an axis. The blade track segment is supported by the carrier radially relative to the axis to define a portion of a gas path of the assembly.

Abstract: A turbine module includes a turbine rotor assembly, a turbine case, and a turbine shroud assembly. The turbine rotor assembly is mounted to rotate about a central reference axis. The turbine case is spaced radially outward from the turbine rotor assembly circumferentially around the central reference axis. The turbine shroud assembly includes a plurality of turbine shroud segments mounted to the turbine case. Each turbine shroud segment includes a blade track segment that faces the turbine rotor assembly and a carrier mounted to the turbine case.

Abstract: A door panel is included in a nacelle assembly for use with a gas turbine engine to block and allow access selectively to the gas turbine engine. The nacelle assembly includes a nacelle wall, a sleeve, and the door panel. The nacelle wall is arranged at least partway around the gas turbine engine and formed to define an opening that extends through the nacelle wall. The door panel is located in the opening and movable relative to the nacelle wall. The sleeve is coupled with one of the nacelle wall and the door panel and configured to move relative to the nacelle wall or the door panel toward and away from the other of the nacelle wall and door panel to adjust a size of a gap between the door panel and the nacelle wall.

Abstract: An example method includes obtaining a representation of a change in rotational speed of an electric machine; obtaining a representation of an expected change in rotational speed of the electric machine; and determining, based on the obtained representation of the change in rotational speed of the electric machine and the representation of an expected change in rotational speed of the electric machine, whether a disconnect device has failed, wherein, when operating in an engaged state, the disconnect device is configured to couple rotational mechanical energy between the electric machine and a rotating device, and wherein, when operating in a disengaged state, the disconnect device is not configured to couple rotational mechanical energy between the electric machine and the rotating device.

Abstract: Systems and methods are disclosed for controlling surge margin in the compressor section of a gas turbine engine. Bypass ports on a first compressor section and second compressor section lead to a bypass conduit. An auxiliary turbine and discharge conduit are positioned in the bypass conduit. Fluid flow from the compressor sections into the bypass conduit via the bypass ports is controlled by bypass control valves.

Abstract: In some examples, a method including applying a wet bond coat slurry to a damaged area of a coating system on a metal substrate, the bond coat slurry including a liquid binder, glass and/or glass-ceramic particles, and ceramic oxide particles; depositing fibers onto the wet bond coat slurry, wherein the fibers include metallic and/or ceramic fibers; applying a ceramic composite slurry on the bond coat while the bond coat is wet or at least partially dried to form a ceramic composite layer, the bond coat including a plurality of partially exposed fibers, wherein, following the application of the ceramic composite slurry, a first portion of fibers of the plurality of fibers are embedded in the bond coat and a second portion of fibers of the plurality of fibers extend into the layer of the ceramic composite slurry; and heating the bond coat and the ceramic composite layer to form a repaired portion of the coating system on the metal substrate, wherein heating the bond coat melts the glass particles and/or the gl

Abstract: Thermal management systems for cooling high-power, low-duty-cycle thermal loads that include at least three thermally coupled, closed subsystems are provided. Thermal management systems provided herein include a main thermal energy storage loop including a cold-temperature tank and a warm-temperature tank. Thermal management systems provided herein also include a multi-stage compression system or a cascaded architecture of a low-temperature vapor compression system and a high-temperature vapor compression system. Methods of transferring heat from one or more thermal loads to an ambient environment are also provided.