Abstract: An over-pressure vent (OPV) system is provided for a fuel tank of an aircraft. The OPV system includes an OPV valve configured to be coupled in fluid communication with a supply line of a nitrogen enriched air distribution system (NEADS) such that the OPV valve is configured to vent pressure from the supply line. The OPV valve is configured to be coupled in fluid communication with the supply line upstream from an outlet of the supply line from which the NEADS delivers nitrogen enriched gas to the fuel tank. The OPV valve is configured to sense a pressure within the supply line upstream from the outlet of the supply line.

Abstract: A noncombustible gas distribution method includes distributing noncombustible gas to a center wing tank throughout a continuous, first flight period and, as a result, reducing flammability exposure time during the first flight period or during a subsequent flight period. The method includes not distributing noncombustible gas to left and right main wing tanks while the noncombustible gas is distributed to the center wing tank throughout the first flight period and while the left and right main wing tanks are non-flammable. A noncombustible gas distribution system includes a noncombustible gas source and distribution tubing from the gas source to left and right main wing tanks and a center wing tank. A distribution mechanism yields a greater proportion of gas flow per tank unit volume distributed to an outboard section of the left and right main wing tanks compared to an inboard section during a climb phase of the aircraft's flight.

Abstract: A noncombustible gas distribution method includes distributing noncombustible gas to a center wing tank throughout a continuous, first flight period and, as a result, reducing flammability exposure time during the first flight period or during a subsequent flight period. The method includes not distributing noncombustible gas to left and right main wing tanks while the noncombustible gas is distributed to the center wing tank throughout the first flight period and while the left and right main wing tanks are non-flammable. A noncombustible gas distribution system includes a noncombustible gas source and distribution tubing from the gas source to left and right main wing tanks and a center wing tank. A distribution mechanism yields a greater proportion of gas flow per tank unit volume distributed to an outboard section of the left and right main wing tanks compared to an inboard section during a climb phase of the aircraft's flight.

Abstract: A noncombustible gas distribution method includes distributing noncombustible gas to a center wing tank throughout a continuous, first flight period and, as a result, reducing flammability exposure time during the first flight period or during a subsequent flight period. The method includes not distributing noncombustible gas to left and right main wing tanks while the noncombustible gas is distributed to the center wing tank throughout the first flight period and while the left and right main wing tanks are non-flammable. A noncombustible gas distribution system includes a noncombustible gas source and distribution tubing from the gas source to left and right main wing tanks and a center wing tank. A distribution mechanism yields a greater proportion of gas flow per tank unit volume distributed to an outboard section of the left and right main wing tanks compared to an inboard section during a climb phase of the aircraft's flight.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig. The method includes producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. An aircraft fuel tank flammability reduction system includes a source for pressurized air, an air separation module configured to receive air feed from the pressurized air source, and a carbon membrane. The carbon membrane is configured to permeate oxygen from the air feed through the carbon membrane at a temperature of at least 120° C. (248° F.) and to produce nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed.

Abstract: A noncombustible gas distribution method includes distributing noncombustible gas to a center wing tank throughout a continuous, first flight period and, as a result, reducing flammability exposure time during the first flight period or during a subsequent flight period. The method includes not distributing noncombustible gas to left and right main wing tanks while the noncombustible gas is distributed to the center wing tank throughout the first flight period and while the left and right main wing tanks are non-flammable. A noncombustible gas distribution system includes a noncombustible gas source and distribution tubing from the gas source to left and right main wing tanks and a center wing tank. A distribution mechanism yields a greater proportion of gas flow per tank unit volume distributed to an outboard section of the left and right main wing tanks compared to an inboard section during a climb phase of the aircraft's flight.

Abstract: A cooling system for a fuel tank of an aircraft includes a temperature sensor, a cooling system, and a control module. The temperature sensor detects a fuel temperature within the fuel tank. The cooling system maintains the fuel temperature below a control temperature. The phase change cooling system includes a heat exchanger. A cooling fluid flows through the heat exchanger and is in thermal communication with a surface of the fuel tank. The control module is in signal communication with the temperature sensor and the cooling system. The control module includes control logic for monitoring the temperature sensor, determining if the fuel temperature is above the control temperature, and generating an activation signal.

Abstract: A gas separation method includes contacting a membrane filter with gas feed, permeating the gas from the gas feed through the membrane, and producing filtered gas from the filter. The filtered gas is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. A gas separation method includes feeding gas into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered gas into a gas separation module that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.

Abstract: A fluid separation assembly and method are provided. The assembly has a hollow fiber bundle with a plurality of hollow fiber membranes. The assembly further has a pair of tubesheets, each encapsulating respective ends of the hollow fiber bundle. The assembly further has a plurality of radial through openings formed along a circumference of one or both of the tubesheets and radially through a body portion in one or both of the tubesheets. The radial through openings include center connected radial through openings and partial radial through openings, and intersect each, or substantially each, of the hollow fiber membranes. The assembly further has a housing surrounding the hollow fiber bundle and the tubesheets. The housing has a feed inlet port, a permeate outlet port, and a non-permeate outlet port. The feed inlet port and the non-permeate outlet port are in parallel alignment with a longitudinal central axis of the housing.

Abstract: A cooling system for a fuel tank of an aircraft includes a temperature sensor, a cooling system, and a control module. The temperature sensor detects a fuel temperature within the fuel tank. The cooling system maintains the fuel temperature below a control temperature. The phase change cooling system includes a heat exchanger. A cooling fluid flows through the heat exchanger and is in thermal communication with a surface of the fuel tank. The control module is in signal communication with the temperature sensor and the cooling system. The control module includes control logic for monitoring the temperature sensor, determining if the fuel temperature is above the control temperature, and generating an activation signal.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing an oxygen separation membrane. The method includes contacting the separation membrane with the air feed, permeating oxygen from the air feed through the separation membrane, and producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. The NEA from the air separation module is substantially cooled in a NEA flow heat exchanger and the substantially cooled, nitrogen-enriched air is fed into the fuel tank on board the aircraft. An aircraft fuel tank flammability reduction system includes a NEA flow heat exchanger configured to cool substantially the nitrogen-enriched air from the air separation module and a fuel tank on board the aircraft configured to receive the cooled nitrogen-enriched air.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig. The method includes producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. An aircraft fuel tank flammability reduction system includes a source for pressurized air, an air separation module configured to receive air feed from the pressurized air source, and a carbon membrane. The carbon membrane is configured to permeate oxygen from the air feed through the carbon membrane at a temperature of at least 120° C. (248° F.) and to produce nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed.

Abstract: A fluid separation assembly and method are provided. The assembly has a hollow fiber bundle with a plurality of hollow fiber membranes. The assembly further has a pair of tubesheets, each encapsulating respective ends of the hollow fiber bundle. The assembly further has a plurality of radial through openings formed along a circumference of one or both of the tubesheets and radially through a body portion in one or both of the tubesheets. The radial through openings include center connected radial through openings and partial radial through openings, and intersect each, or substantially each, of the hollow fiber membranes. The assembly further has a housing surrounding the hollow fiber bundle and the tubesheets. The housing has a feed inlet port, a permeate outlet port, and a non-permeate outlet port. The feed inlet port and the non-permeate outlet port are in parallel alignment with a longitudinal central axis of the housing.

Abstract: In an embodiment there is provided a fluid separation assembly. The assembly has a hollow fiber bundle with a plurality of hollow fiber membranes. The assembly further has a first tubesheet and a second tubesheet encapsulating respective ends of the hollow fiber bundle, wherein one of the tubesheets has a plurality of radial through openings formed in the tubesheet. The assembly further has a housing surrounding the hollow fiber bundle and the first and second tubesheets, the housing having a feed inlet port, a permeate outlet port, and a non-permeate outlet port. The feed gas, permeate gas, or non-permeate gas are introduced into or removed from the hollow fiber membranes via the plurality of radial through openings formed in the tubesheet, such that the radial through openings of the tubesheet intersect each or substantially each of the hollow fiber membranes.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon. The method includes producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. An aircraft fuel tank flammability reduction system includes a source for pressurized air, an air separation module configured to receive air feed from the pressurized air source, and a carbon membrane containing at least 95 weight percent carbon. The carbon membrane is configured to permeate oxygen from the air feed through the carbon membrane at a temperature of at least 120° C. (248° F.) and to produce nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed.

Abstract: A gas separation method includes contacting a membrane filter with gas feed, permeating the gas from the gas feed through the membrane, and producing filtered gas from the filter. The filtered gas is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. A gas separation method includes feeding gas into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered gas into a gas separation module that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing an oxygen separation membrane. The method includes contacting the separation membrane with the air feed, permeating oxygen from the air feed through the separation membrane, and producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. The NEA from the air separation module is substantially cooled in a NEA flow heat exchanger and the substantially cooled, nitrogen-enriched air is fed into the fuel tank on board the aircraft. An aircraft fuel tank flammability reduction system includes a NEA flow heat exchanger configured to cool substantially the nitrogen-enriched air from the air separation module and a fuel tank on board the aircraft configured to receive the cooled nitrogen-enriched air.

Abstract: An aircraft fuel tank flammability reduction method includes contacting a membrane filter with air feed, permeating oxygen and nitrogen from the air feed through the membrane, and producing filtered air from the filter. The filtered air is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. An air separation method includes feeding air into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered air into an air separation module containing a hollow fiber membrane that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.

Abstract: An aircraft fuel tank flammability reduction method includes contacting a membrane filter with air feed, permeating oxygen and nitrogen from the air feed through the membrane, and producing filtered air from the filter. The filtered air is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. An air separation method includes feeding air into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered air into an air separation module containing a hollow fiber membrane that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.

Abstract: An aircraft fuel tank flammability reduction method includes feeding pressurized air into an air separation module containing a carbon membrane, the air feed exhibiting a normal pressure of no more than 55 psig and the carbon membrane containing at least 95 weight percent carbon. The method includes producing nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed. An aircraft fuel tank flammability reduction system includes a source for pressurized air, an air separation module configured to receive air feed from the pressurized air source, and a carbon membrane containing at least 95 weight percent carbon. The carbon membrane is configured to permeate oxygen from the air feed through the carbon membrane at a temperature of at least 120° C. (248° F.) and to produce nitrogen-enriched air from the air separation module as a result of removing oxygen from the air feed.