A seal system includes a ceramic component, a metallic component, a silicon-containing layer, and a barrier layer. The ceramic component has a first surface region that defines a first surface roughness. The metallic component is situated adjacent to the first surface region and has a second surface region facing the first surface region. The silicon-containing layer is on the first surface region of the ceramic component and has a contact surface that defines a second surface roughness which is less than the first surface roughness. The barrier layer is on the metallic component and in contact with the silicon-containing layer and serves to limit interaction between silicon of the silicon-containing layer and the metallic component. The barrier layer includes at least one of alumina or MCrAlY.

A power source for an aircraft having a gas turbine engine, including: an electrical connection assembly; a fuel cell assembly integrated into the gas turbine engine, electrically coupled to the connection assembly and configured to provide a first power output; and an electric machine coupled to the gas turbine engine, electrically coupled to the connection assembly and configured to provide a second power output, wherein both the first power output from the fuel cell assembly and the second power output from the electric machine are provided to the connection assembly during operating of the gas turbine engine and wherein the connection assembly is electrically coupled to an aircraft electrical load.

A seal system includes a ceramic component, a metallic component, a coating system. The ceramic component has a first surface region that defines a first surface roughness. The metallic component is situated adjacent to the first surface region and has a second surface region facing the first surface region. The coating system includes a silicon-containing layer on the surface region of the ceramic component and barrier layer on the silicon-containing layer. The silicon containing layer has a surface in contact with the barrier layer and the barrier layer has a surface in contact with the metallic component. The surface of the barrier layer has a second surface roughness that is less than the first surface roughness. The barrier layer serves to limit interaction between silicon of the silicon-containing layer and elements of the metallic component. The barrier layer includes at least one of mullite, zircon, or hafnon.

A method of producing compressed air for use onboard an aircraft includes receiving compressor discharge air into an air channel of a fuel injector. The method also includes cooling the compressor discharge air within the air channel by heat exchange with fuel flowing in the fuel injector, and issuing cooled air from the internal air channel out of an engine case as a source of compressed air.

A gas turbine engine includes a compressor section with a compressor rotor shaft assembly including a plurality of compressor rotors longitudinally spaced apart from each other via respective ones of a plurality of shaft sections of a rotor shaft, each compressor rotor of the plurality of compressor rotors having a plurality of rotor vanes extending radially outward therefrom and being circumferentially spaced about the compressor rotor. A stator shroud assembly has a stator shroud casing surrounding the compressor rotor shaft assembly, a compressor flow passage being defined between the compressor rotor shaft assembly and the stator shroud casing. A pressurized air source generates a flow of pressurized air to be provided to the compressor section, and a plurality of pressurized airflow nozzles are connected with the pressurized air source and provide the flow of pressurized air into the compressor flow passage to cause the compressor rotor shaft assembly to rotate.

A rocket engine system comprising a rocket engine, coolant and a coolant source, propellant and a propellant source, a turbopump, and a heat source. The coolant is pressurized and then heated through a heat source to a supercritical state for augmented heat transfer. The heat source may be a heat exchanger with returning coolant, or a preburner. The rocket engine system may further comprise at least one additional rocket engine with a pump to provide pressure for multiple engine. The rocket engine system may further comprise multiple turbopump shafts for independent control of propellants.

A turbine engine system includes aircraft systems including at least one hydrogen fuel tank, engine systems comprising a compressor section, a combustor section having a burner, and a turbine section, and a hydrogen fuel flow supply line configured to supply hydrogen fuel from the at least one hydrogen fuel tank into the burner for combustion. The turbine engine system has a bypass ratio between 5 to 20.

A method to produce a ceramic matrix composite with controlled surface characteristics includes: applying a scrim ply to a surface of a fiber preform, where the fiber preform includes silicon carbide fibers coated with boron nitride; infiltrating the fiber preform and the scrim ply with a slurry, thereby forming an impregnated ply on an impregnated fiber preform; infiltrating the impregnated fiber preform and the impregnated ply with a melt comprising silicon, and then cooling, thereby forming a ceramic matrix composite having a ceramic surface layer thereon, where the ceramic surface layer has a predetermined thickness and is devoid of boron; machining or grit blasting the ceramic surface layer to form an intermediate layer suitable for coating; and depositing an environmental barrier coating on the intermediate layer. Thus, a ceramic matrix composite coated with the environmental barrier coating is formed with the intermediate layer in between.

A fuel/air supply device including a fuel supply arrangement designed to convey fuel to a fuel outlet of the fuel/air supply device, a primary air supply arrangement designed to convey air to an air outlet of the fuel/air supply device, and a secondary air supply arrangement connecting the primary air supply arrangement to the fuel supply arrangement at a position upstream of a fuel compressor that is included in the fuel supply arrangement. The secondary air supply arrangement includes an air conduit that has a restricted portion for defining a relatively small air passage in the air conduit, and can be used for realizing a fuel/air mixture of low calorific value if so desired on the basis of a supply of air to the fuel without needing complex control measures.

An apparatus and method regarding an airfoil for a turbine engine, the airfoil comprising an outer wall defining an interior bound by a pressure side and a suction side extending axially between a leading edge and a trailing edge defining a chord-wise direction and extending radially between a root and a tip defining a span-wise direction. The airfoil further comprising at least one cooling passage extending radially within the interior and defining a primary cooling airflow; and at least one cooling hole having an inlet defining a first cross-sectional area, the inlet in communication with the cooling passage, an outlet defining a second cross-sectional area greater than the first cross-sectional area; wherein the primary cooling airflow enters the inlet in a first direction and exits the outlet in a second direction different than the first direction.