A vacuum system for use with a deoxygenator system includes a housing, a movable assembly positioned within the housing, and a biasing mechanism coupling the movable assembly to the housing. The movable assembly is movable between a first position and a second position within the housing to form a low pressure area between the housing and the movable assembly. A control system including at least one pressure source is arranged in fluid communication with the low pressure area. The control system is operable to selectively communicate fluid from the at least one pressure source to the housing to form the low pressure area.

An aircraft fuel deoxygenation system includes a boost pump, a contactor-separator, and a centrifuge-separator pump. The boost pump is adapted to receive fuel from a fuel source and inert gas from an inert gas source, and is configured to mix the fuel and inert gas and supply a fuel/gas mixture. The contactor-separator is coupled to receive the fuel/gas mixture and is configured to remove oxygen from the fuel and thereby generate and supply deoxygenated fuel with entrained purge gas and separated purge gas. The centrifuge-separator pump is coupled to receive the deoxygenated fuel with entrained purge gas and is configured to separate and remove the entrained purge gas from the deoxygenated fuel and supply the deoxygenated fuel and additional purge gas.

A nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer air flow path, and a core conduit defined radially inward from the inner gas flow path. An injector assembly includes an outer housing, a nozzle within the outer housing, and an outer housing gas flow path defined radially outward from the nozzle between an inner surface of the outer housing and an outer surface of the nozzle. The nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer gas flow path and a core conduit defined radially inward from the inner gas flow path.

An aircraft including a combustion engine with a combustion chamber an injection device for injecting fuel in the combustion chamber and an air separation device adapted to separate air into an oxygen-enriched gas mix and an nitrogen-enriched gas mix, wherein the oxygen-enriched gas mix is injected into the combustion chamber with the fuel while the nitrogen-enriched gas mix is used to inert at least some portions of the aircraft in the environment of said combustion engine.

In one exemplary embodiment of the present disclosure, a method of operating a fuel system for an aeronautical gas turbine engine is provided. The method includes: providing a flow of fuel to a fuel nozzle of the aeronautical gas turbine engine during a wind down condition; operating a fuel oxygen reduction unit to reduce an oxygen content of the flow of fuel provided to the fuel nozzle of the aeronautical gas turbine engine during the wind down condition; and ceasing providing the flow of fuel to the fuel nozzle of the aeronautical gas turbine engine, the fuel nozzle comprising a volume of fuel after ceasing providing the flow of fuel to the fuel nozzle; wherein operating the fuel oxygen reduction unit comprises operating the fuel oxygen reduction unit to reduce an oxygen content of the volume of fuel in the fuel nozzle to less than 20 parts per million.

An aircraft including a combustion engine with a combustion chamber an injection device for injecting fuel in the combustion chamber and an air separation device adapted to separate air into an oxygen-enriched gas mix and an nitrogen-enriched gas mix, wherein the oxygen-enriched gas mix is injected into the combustion chamber with the fuel while the nitrogen-enriched gas mix is used to inert at least some portions of the aircraft in the environment of said combustion engine.

In one exemplary embodiment of the present disclosure, a method of operating a fuel system for an aeronautical gas turbine engine is provided. The method includes: providing a flow of fuel to a fuel nozzle of the aeronautical gas turbine engine during a wind down condition; operating a fuel oxygen reduction unit to reduce an oxygen content of the flow of fuel provided to the fuel nozzle of the aeronautical gas turbine engine during the wind down condition; and ceasing providing the flow of fuel to the fuel nozzle of the aeronautical gas turbine engine, the fuel nozzle comprising a volume of fuel after ceasing providing the flow of fuel to the fuel nozzle; wherein operating the fuel oxygen reduction unit comprises operating the fuel oxygen reduction unit to reduce an oxygen content of the volume of fuel in the fuel nozzle to less than 20 parts per million.

A fuel oxygen reduction unit for an engine is provided. The fuel oxygen reduction unit includes an inlet fuel line; a stripping gas source; a contactor selectively in fluid communication with the stripping gas source, the inlet fuel line, or both to form a fuel/gas mixture; and a separator that receives the fuel/gas mixture, the separator configured to separate the fuel/gas mixture into an outlet stripping gas flow and an outlet fuel flow; wherein a flow of stripping gas passes through the fuel oxygen reduction unit a single time.

A fuel delivery system for a gas turbine engine includes a fuel source; a draw pump downstream of the fuel source for generating a liquid fuel flow from the fuel source; a main fuel pump downstream of the draw pump; and a fuel oxygen reduction unit downstream of the draw pump and upstream of the main fuel pump. The fuel oxygen reduction unit includes a stripping gas line; a contactor in fluid communication with the stripping gas line and the draw pump for forming a fuel/gas mixture, wherein the contactor receives an inlet fuel flow from the draw pump; a separator in fluid communication with the contactor, the separator receives the fuel/gas mixture and separates the fuel/gas mixture into an outlet stripping gas flow and an outlet fuel flow at a location upstream of the main fuel pump; a catalyst disposed downstream of the separator, the catalyst receives and treats the outlet stripping gas flow, wherein a stripping gas stream flows out the catalyst; and a water removal component disposed between the catalyst and the contactor, wherein the water removal component removes water from the stripping gas stream.

A fuel oxygen reduction unit for an engine is provided. The fuel oxygen reduction unit includes an inlet fuel line; a stripping gas source; a contactor selectively in fluid communication with the stripping gas source, the inlet fuel line, or both to form a fuel/gas mixture; and a separator that receives the fuel/gas mixture, the separator configured to separate the fuel/gas mixture into an outlet stripping gas flow and an outlet fuel flow; wherein a flow of stripping gas passes through the fuel oxygen reduction unit a single time.