Abstract: A gas turbine engine generates noise during use, and one particularly important flight condition for noise generation is take-off. A gas turbine engine that has high efficiency provides low noise, in particular from the fan and the turbine that drives the fan. Values are defined for a noise parameter NP that results in a gas turbine engine having reduced combined fan and turbine noise.

Abstract: The present disclose provides a method of manufacturing a turbine component for a gas turbine engine, comprising: forming, by a casting process, a primary component; forming, by an additive manufacturing process, a secondary component, wherein the secondary component comprises a main air passageway extending therethrough; assembling the primary component and the secondary component together to form the turbine component, wherein the main air passageway of the secondary component forms part of an internal air flow path through the turbine component.

Abstract: A tie for a component includes a body including an elongate portion and an arch disposed adjacent to the elongate portion. The arch includes first and second middle surfaces extending between a pair of first and second outer curved surfaces, respectively. The body defines a minimum cross-sectional plane perpendicular to a longitudinal axis and passing through the elongate portion. The body further includes a minimum tie width at the minimum cross-sectional plane along a second transverse axis. The minimum tie width is greater than each of a first minimum arch width of the first middle surface and a second minimum arch width of the second middle surface by a width factor greater than or equal to 3 to less than or equal to 10.

Abstract: A turbine shroud segment, e.g. for a gas turbine engine, which is coolable by a supply of cooling air, e.g. from a gas turbine engine compressor. The turbine shroud segment has a segment casing that has a radially outer surface and a radially inner surface. The segment casing houses a main plenum, a first layer of impingement chambers, a second layer of impingement chambers, and a plurality of effusion passages. The first layer of impingement chambers fluidly communicates with the main plenum via transfer passages that are formed in the segment casing. The second layer of impingement chambers fluidly communicates with the first layer of impingement chambers via impingement passages that are formed in the segment casing. The effusion passages run between impingement chamber core surface, which is a radially inner surface of an impingement chamber, and the radially inner surface of the segment casing.

Abstract: Disclosed is a fuel system for a gas turbine engine having a core exhaust and a combustion section. The system comprises a fuel pump for fluid communication with a fuel reservoir; a driving turbine for driving the fuel pump; and an air feed to drive the driving turbine, the air feed being fluidly connectable to the core exhaust of the gas turbine engine. Also disclosed is a fuel system comprising: a fuel pump for fluid communication with a fuel reservoir; a fuel line from the fuel pump for fluid communication with the combustion section of the gas turbine engine; and an air feed to a heat exchanger, the air feed being fluidly connectable to the core exhaust of the gas turbine engine, wherein the fuel line is in thermal communication with the air feed within a heat exchanger.

Abstract: In some examples, systems and techniques for repairing or otherwise forming a blade of a bladed disk. In one example, a method including positioning a shield member around a perimeter of a partial blade extending from a rotor disk of a bladed disk, the shield member being positioned adjacent to a build surface of the partial blade; and depositing, with the shield member around the perimeter of the partial blade, a material on the build surface using an additive manufacturing technique to form a repaired portion on the build surface of the partial blade.

Abstract: A method of electropolishing an internal passageway of a component, wherein the passageway has an inlet and an outlet; including: providing an electrode assembly including a flexible electrode, a shuttle and a guide cable extending between the flexible electrode and the shuttle; inserting the shuttle into the inlet; causing fluid to flow through the passageway to transport the shuttle through the passageway from the inlet towards the outlet; pulling the guide cable through the passageway to position the electrode in the passageway adjacent to a region of the passageway to be polished; and electropolishing the passageway using the electrode while moving the electrode within the passageway. Also, an electrode assembly for electropolishing an internal passageway of a component, including: a flexible electrode, a shuttle, and a guide cable extending between the flexible electrode and the shuttle.

Abstract: A thermal management system for an aircraft comprises a first gas turbine engine, a first thermal bus, a first heat exchanger, and a chiller. The first thermal bus comprises a first heat transfer fluid, with the first heat transfer fluid being in fluid communication, in a closed loop flow sequence, between the first gas turbine engine, the first heat exchanger, and the chiller. Waste heat energy generated by the first gas turbine engine, is transferred to the first heat transfer fluid. The chiller is configured to lower a temperature of the first heat transfer fluid prior to the first heat transfer fluid being circulated through the gas turbine engine. The first heat exchanger is configured to transfer the waste heat energy from the first heat transfer fluid to a dissipation medium.

Abstract: An inner cowl arrangement for a gas turbine engine includes a first hinge and a second hinge pivotally connecting a first cowl member and a second cowl member, respectively, to a mounting structure. The inner cowl arrangement further includes a latch detachably securing the first and second cowl members. At least one of the first hinge, the second hinge, and the latch includes a pressure relief component that deforms or breaks when an applied load on the pressure relief component due to a pressure within an engine core is greater a normal operating load, causing at least one of the first cowl member and the second cowl member to move relative to the engine core, and forming an opening.

Abstract: A rotary assembly for driving spool rotation includes a rotor and a flow modifier. The rotor is mechanically coupled to a spool of a gas turbine engine. The flow modifier receives flow from and/or direct flow to the rotor. The rotary assembly permits relative movement between the rotor and the flow modifier to move between: a turbine configuration wherein the rotor receives air from an external air source to drive the spool to rotate; and a compressor configuration wherein the rotor is driven to rotate by the spool and to receive and compress air from the gas turbine engine, and discharge the compressed air for supply to the airframe system. The rotary assembly also includes controller to control relative movement between the rotor and the flow modifier through a range of turbine positions of the turbine configuration to vary a torque applied to the rotor for driving the spool.

Abstract: A micromanipulator for mounting on the end of a macromanipulator, the micromanipulator comprising: a connection plate with a at least a first and second motor connected to a rigidly mounted base section, a first rotational section connected to the base section about a pivotable axis, the first rotational section being further connected to a slider rod which is connected to the first motor, and a second rotational section connected to the first rotational section about a pivotable axis, the second rotational section being further connected to a slider rod which is connected to the second motor and wherein the rotational joints between the base section and first joint section and the rotational joint between the first and second rotational sections are offset by 90°.

Abstract: A gas turbine engine for an aircraft comprises, in axial flow sequence, a compressor module, a combustor module, and a turbine module, with a first electric machine being rotationally connected to the turbine module. The first electrical machine is configured to generate a maximum electrical power PEM1 (W), and the gas turbine engine is configured to generate a maximum dry thrust T (N); and a ratio S of: S = ( Maximum ? Electrical ? Power ? Generated = P E ? M ? 1 ) ( Maximum ? Dry ? Thrust = T ) is in a range of between 2.0 and 10.0.

Abstract: An article may include a substrate including a ceramic matrix composite (CMC); a composite coating layer including a first coating material that includes a rare-earth disilicate and a second coating material that includes at least one of a rare-earth monosilicate, a CMAS-resistant material, or a high-temperature dislocating material, where the second coating material forms a substantially continuous phase in the composite coating layer.

Abstract: Described herein is a flow splitter for a gas turbine engine, the flow splitter comprising a leading edge, wherein the radial and/or axial position of the leading edge varies circumferentially around the flow splitter, such that the leading edge is non-axisymmetric. Also described is a method of manufacture of a flow splitter and an engine comprising a flow splitter.

Abstract: The present disclosure provides a method of manufacturing a turbomachinery component for a gas turbine engine, comprising: receiving an ideal design of the turbomachinery component, the turbomachinery component comprising: an aerofoil portion comprising an aerofoil surface and having an ideal aerofoil wall thickness; and a platform portion comprising a platform surface coterminous with the aerofoil surface, the platform portion having an ideal radial platform thickness along a radial direction; determining an intermediate design of the turbomachinery component comprising an intermediate platform portion having an intermediate platform surface and an intermediate radial platform thickness which is greater than the ideal radial platform thickness; forming, by an investment casting process, an intermediate turbomachinery component based on the intermediate design, wherein the intermediate turbomachinery component comprises at least one detectable reference feature formed by an internal core element during the in

Abstract: A fan blade includes an aerofoil portion including a leading edge extending from a root to a tip and defining a blade span therebetween. A leading edge thickness is defined as a thickness of a cross-section at a given radius at a location along a camber line that is 9% of the total length of the camber line from the leading edge. For cross-sections through the aerofoil portion at radii between 50% and 70% of the blade span from a root radius, the leading edge thickness includes a first maximum value. For cross-sections through the aerofoil portion at radii greater than 70% of the blade span from the root radius, the leading edge thickness includes a second maximum value that is between 105% and 125% of the first maximum value.

Abstract: The disclosure relates to an electrical power system with current fault protection provided by current limiting diodes. Example embodiments include an electrical power system comprising: an electrical machine; an AC:DC power electronics converter connected to receive an input AC supply from the electrical machine and provide an output DC supply across first and second output terminals; a DC bus connected to first and second output terminals of the AC:DC power electronics converter; a load connected across the DC bus; a first circuit breaker switch and a first current limiting diode connected in series between the AC:DC power electronics converter and the DC bus; and a second circuit breaker switch and a second current limiting diode connected in series between the DC bus and the load, wherein the first current limiting diode is configured to limit current to a higher level than the second current limiting diode.

Abstract: A fuel delivery system (201) is shown for delivering the hydrogen fuel from a cryogenic storage system to a fuel injection system in a gas turbine engine. The fuel delivery system includes a pump (301), a metering device (302), and a fuel heating system (303,304) for heating the hydrogen fuel to an injection temperature for the fuel injection system.

Abstract: There is provided a method of starting a gas turbine engine, comprising: selecting a baseline starting procedure of the gas turbine engine based on environmental data; receiving condition information for the gas turbine engine and/or for a starting system of the gas turbine engine, the condition information comprising at least one of: health information for the gas turbine engine and/or the starting system; maintenance information for the gas turbine engine and/or the starting system; and operation information relating to an expected future usage of the gas turbine engine. The method further comprises determining a predicted degradation profile for the gas turbine engine and/or the starting system based on the condition information; determining a starting procedure of the gas turbine engine by adapting the baseline starting procedure based on the predicted degradation profile; and controlling the gas turbine engine and/or the starting system according to the determined starting procedure.

Abstract: A combined gas turbine engine and hydrogen fuel cell system includes a hydrogen fuelled gas turbine engine, a cryogenic liquid hydrogen fuel tank, a first fuel offtake configured and arranged to divert a portion of hydrogen fuel from a main fuel conduit, a burner configured and arranged to burn the portion of hydrogen fuel diverted from the main fuel conduit, a heat exchanger configured and arranged to transfer heat from exhaust gasses produced by the burner to hydrogen fuel in the main fuel conduit, a second fuel offtake arranged to divert a portion of hydrogen fuel from the main fuel conduit downstream of the heat exchanger, and a hydrogen fuel cell configured and arranged to produce electric power using hydrogen fuel diverted from the second fuel offtake.