Abstract: A method of analysing a non-contact excitation system for a spin rig includes, calculating a magnetic field per test piece element, integrating the magnetic field over the test piece element surface to get a force per test piece element, performing a Fourier analysis of the forces acting on the test piece element as it moves past the periodic array of exciter elements, calculating the damping added to the test piece element due to magnetic induction, calculating a vibration response of the test piece element as it moves past the stationary array of exciter elements, calculating a transient response of the test piece element where the stationary array of exciter elements is rapidly moved away from the test piece elements, and using the calculated transient response of the test piece element to calculate a required electromagnetic holding force for the array of exciter elements.

Abstract: An additive manufacturing system includes an energy delivery device configured to deliver, a powder delivery device, and one or more thermal sensors configured to measure a temperature of a first portion of the additively-manufactured component and a second portion of the additively manufactured component. The additive manufacturing system includes a computing device configured to receive data indicative of the temperature of the first portion and of the second portion, determine a residual stress of the additively-manufactured component based at least partially on the received thermal sensor data from the first portion of the additively-manufactured component and the received data from the second portion of the additively-manufactured component; and predict final dimensions of the additively-manufactured component based at least partially on the determined residual stress of the additively-manufactured component.

Abstract: An additive manufacturing system includes an energy delivery device to deliver energy to a build surface of a deposit overlying a substrate to form a melt pool in the build surface, a powder delivery device to direct a powder stream toward the melt pool, and a computing device to determine a first set of deposition parameters for an innermost layer of the deposit overlying the substrate, determine a second set of deposition parameters for an inner plurality of layers of the deposit overlying the innermost layer, determine a third set of deposition parameters for an outer plurality of layers of the deposit overlying the inner plurality of layers, and control the energy delivery device and the powder delivery device to deposit the innermost layer, the inner plurality of layers, and the outer plurality of layers based on the respective first, second, and third sets of deposition parameters.

Abstract: A method for determining grain structure in a component includes disposing the component on a support platform. The method includes generating an imaging beam. The method includes rotating and/or revolving an imaging beam source and an imaging beam receiver relative to the support platform. The method includes acquiring, during the rotation and/or revolution a plurality of projections each taken at the imaging beam receiver. The method includes performing reconstruction, by a processor, of first projections and second projections from the plurality of projections to obtain a first three-dimensional image and at least one second three-dimensional image. The first projections are acquired in at least one first angular range and the second projections are acquired in at least one second angular range.

Abstract: This disclosure relates to cooling modules for power electronics converters. Example embodiments include a cooling module (100) for a power electronics converter, comprising: first face (101) having a cooling liquid inlet (102); an opposing second face (103) having a cooling liquid outlet (104); a plurality of side walls (105a-d) extending between the first and second faces (101, 103), each side wall (105a-d) being configured for cooling a semiconductor switching device (1061-6) of the power electronics converter; and a helical cooling channel (107) extending through the cooling module between the cooling liquid inlet (102) and the cooling liquid outlet (104).

Abstract: A gas turbine engine for an aircraft comprises an engine core. The engine comprises a fan located upstream of the engine core. The engine comprises a nacelle surrounding the fan and the engine core and defining a bypass duct, where the bypass ratio, defined as the ratio of the mass flow rate of the flow through the bypass duct to the mass flow rate of the flow through the core at cruise conditions, is at least 4. The engine comprises a plurality of actuators and a fuel supply system arranged to supply fuel for combustion in the combustor, and to supply fuel to fueldraulically drive at least one actuator. The fuel comprises at least 25% SAF by volume, and the fuel supply system is arranged such that a peak differential pressure of the fuel across the at least one fueldraulic actuator during cruise conditions is at least 2400 kPa.

Abstract: A gas turbine engine includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the combustion chamber. The nozzles include a first and second subset. Each of the nozzles of the first subset is supplied with fuel at a greater flow rate than each of the second subset. A ratio of nozzles in the first subset to the second subset is 1:2 to 1:5. An MTO nvPM emissions index ratio-modified fuel flow is EI maxTO , SAF EI maxTO , FF × W f , maxTO . EImaxTO,SAF is nvPM emissions index in mg/kg of the engine operating at around 100% available thrust with sustainable aviation fuel. EImaxTO,FF is nvPM emissions index in mg/kg of the engine operating at around 100% available thrust with fossil-based hydrocarbon. Wf,maxTO is mass flow rate of fuel to the nozzles in kg/s operating at around 100% available thrust. The MTO nvPM emissions index ratio-modified fuel flow in kg/s is less than 2.

Abstract: There is disclosed an exhaust nozzle 30 for a gas turbine engine, comprising an exhaust structure 32 and a flap 34 configured to bound a passageway 36 through the exhaust structure. The flap 34 is coupled to the exhaust structure in a linkage arrangement configured to move the flap by compound translation and rotation with a single degree of freedom between a first orientation corresponding to a maximum throat area of the passageway and a second orientation corresponding to a minimum throat area of the passageway.

Abstract: A gas turbine engine for an aircraft. The gas turbine engine includes a rich burn, quick quench, lean burn combustor having 14-22 fuel spray nozzles or 2-6 fuel spray nozzles per unit engine core size. A thrust nvPM emissions index ratio is EI maxTO / EI maxTO EI idle / F idle . EIidle is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine operating at around 7% available thrust; EImaxTO is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine operating at around 100% available thrust; FmaxTO is the thrust of the gas turbine engine at around 100% available thrust in kN, Fidle is the thrust of the gas turbine engine at around 7% available thrust in kN; the thrust nvPM emissions index ratio is greater than 0.09; and the gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel to the fuel spray nozzles.

Abstract: A method of operating a gas turbine engine with a heat exchange system including an air-oil heat exchanger through which oil flows; a fuel-oil heat exchanger through which the oil and fuel flow to transfer heat between the oil and fuel; and a temperature sensor to indicate fuel temperature downstream of the fuel-oil heat exchanger; and a valve to allow at least one of oil and air flow rate through at least one of the fuel-oil heat exchanger and the air-oil heat exchanger to be varied. The method includes determining if the fuel temperature has increased above a set threshold at cruise conditions; and in response to determining that the fuel temperature has increased above the set threshold at cruise conditions, controlling the at least one valve to change the flow rate through heat exchanger.

Abstract: A gas turbine engine for an aircraft includes an engine core with a turbine, a combustor, a compressor, and a core shaft connecting the turbine to the compressor. The engine includes a fan upstream of the engine core and driven by the core shaft. The engine includes a nacelle surrounding the fan and engine core and defining a bypass duct radially outside of the engine core. The bypass ratio, defined as the ratio of the mass flow rate through the bypass duct to the mass flow rate through the core at cruise conditions, is at least 4. The engine includes a generator heat management system and an actuator to actuate a valve within the generator heat management system. The engine comprises a fuel supply system arranged to supply fuel to fueldraulically drive the actuator. The actuator enables non-binary position adjustment between an open valve position and a closed valve position.

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 is provided that has high efficiency together with low noise, in particular from the fan and the turbine that drives the fan. Values are defined for a combined contribution of the turbine noise and the noise from the fan emanating from the front of the engine to the Effective Perceived Noise Level (EPNL) at take-off to be in the range of from 2 EPNdB and 15 EPNdB lower than the EPNL of the whole engine at take-off.

Abstract: A climatic test conditioning apparatus for conditioning a machine for climatic testing comprises a base and an inflatable wall connected to the base. The inflatable wall has at least one port for at least partial inflation and deflation of the inflatable wall. The at least partially inflated inflatable wall and base define a volume that envelopes the machine. Also disclosed is a system and method for climatic test conditioning a machine.

Abstract: A fuel system for a gas turbine engine is disclosed. The fuel system is configured to combust hydrogen fuel and comprises a fuel conduit, a first fuel pump configured to operate on liquid hydrogen within the fuel conduit and a second fuel pump downstream in hydrogen fuel flow of the first fuel pump. The first fuel pump comprises one of a side channel and a regenerative pump and the second fuel pump comprises a centrifugal pump. Methods of operation, a gas turbine engine comprising the fuel system, and an aircraft comprising the gas turbine engine are also disclosed.

Abstract: An intercomponent seal arrangement includes a plurality of wall segments extending circumferentially. Adjacent wall segments from the plurality of wall segments include opposing first and second end wall portions defining a gap therebetween. The gap includes a saddle portion facing radially outwards and including a first sealing face on the first end wall portion and a second sealing face on the second end wall portion. The intercomponent seal arrangement further includes an intercomponent seal located within the saddle portion and including at least a first contact point contacting the first sealing face, a second contact point contacting the second sealing face, and a third contact point radially inwards from the first and second contact points and contacting one of the first and second sealing faces.

Abstract: A method of operating a gas turbine engine and a gas turbine engine includes a fuel delivery system arranged to provide fuel, a combustor arranged to combust at least a proportion of the fuel, a primary fuel-oil heat exchanger arranged to have up to 100% of the fuel provided by the fuel delivery system flow therethrough, and a secondary fuel-oil heat exchanger arranged to have a proportion of the fuel from the primary fuel-oil heat exchanger flow therethrough. Fuel is arranged to flow from the primary fuel-oil heat exchanger to the secondary fuel-oil heat exchanger whereas oil is arranged to flow from the secondary fuel-oil heat exchanger to the primary fuel-oil heat exchanger. A fuel viscosity is adjusted to a maximum of 0.58 mm2/s on entry to the combustor at cruise conditions.

Abstract: A needle apparatus for making a pinning hole in a composite material, the apparatus having a needle with a longitudinal axis, a collar fixed about the needle, a motor having an axis of rotation, and being fixed to the needle such that the needle can be rotated by the motor, the motor and the collar being situated within a motor housing, the motor housing having a first bush, and a second bush, wherein the collar is positioned between the first bush and second bush so as to prevent the needle from moving away from or towards the motor, but allow the needle to rotate freely around its longitudinal axis, wherein each needle apparatus further comprises a linear actuator connected to the motor such that the motor can be moved along the axis of rotation of the motor by the linear actuator.

Abstract: A gas turbine engine for aircraft includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the combustion chamber. The fuel spray nozzles include a first subset and a second subset of nozzles. Each of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of the first subset to the second subset is 1:2 to 1:5. A MTO nvPM emissions index ratio is EI maxTO , SAF EI maxTO , FF . EImaxTO,SAF is nvPM emissions index in mg/kg of the engine when operating at around 100% available thrust if fuel provided to the fuel spray nozzles includes sustainable aviation fuel. EImaxTO,FF is nvPM emissions index in mg/kg of the engine when operating at around 100% available thrust if fuel provided to the fuel spray nozzles is fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio is less than 1.

Abstract: There is provided a method of monitoring the health of an asset. The method comprises obtaining a measured value of an input parameter representing an operational state of the asset, determining, based on the value, a residual that represents the behaviour of the asset, providing the determined residual to an encoder model to map the determined residual to a data point in a feature space, determining a distance of the data point relative to a cluster of data points in the feature space, wherein the cluster of data points are determined by the encoder based on residuals representing nominally healthy assets, and in response to the determined distance exceeding a predetermined distance threshold, generating an abnormal asset behaviour prediction.

Abstract: There is provided a method of monitoring the health of an asset. The method comprises providing an input representing the behaviour of the asset to an encoder model to map the input to a data point in a feature space, wherein the encoder model is configured to cause data points relating to measured values of input parameters acquired from the asset at a similar time to cluster in feature space, determining a distance of the data point relative to a cluster of data points in feature space, where the cluster of data points are determined by the encoder based on inputs representing the asset over a first time period, and in response to the determined distance exceeding a predetermined distance threshold, generating an abnormal asset behaviour prediction.