Patent Description:
Vehicles, such as aircraft, commonly carry liquid fuel in fuel tanks. The fuel tanks generally define an interior ullage space between the liquid fuel and the interior of the fuel tank. The ullage space is typically occupied by a mixture of fuel vapor and ambient air. Such fuel vapor-air mixtures can present a fire hazard concentration of oxygen within the ullage space is sufficient to support combustion. To limit (or eliminate entirely) the combustion risk posed by such fuel vapor-air mixtures some vehicles employ inerting systems to control oxygen concentration with the vehicle fuel tank. Examples of inerting systems include nitrogen generation systems with air separation modules. The air separation modules in such inerting system can be employed to communicate oxygen-depleted air flows to the vehicle fuel tank to limit oxygen concentration within the fuel tank ullage space.

Air separation modules typically separate pressurized air into an oxygen-depleted fraction and an oxygen-enriched fraction. The oxygen-depleted air flow is generally communicated to the vehicle fuel tank, that the oxygen-depleted air flow limits concentration of oxygen within the fuel tank. The oxygen-enriched air flow is typically diverted to the external environment. The oxygen-depleted air flow generation capacity of the air separation module is typically limited by external support structure and/or framing employed to structurally support the air separation module.

Such systems and methods have generally been acceptable for their intended purpose. However, there remains a need for improved air separation modules, nitrogen generation systems, and methods of making air separation modules for nitrogen generation systems. <CIT> relates to a gas separation membrane module. <CIT> relates to a canister system for an air separation module.

<CIT> relates to an air separation module. <CIT> relates to a gas separation module.

An air separation module according to claim <NUM> is provided.

In addition to the features of claim <NUM>, further examples of the air separation module may include that the canister has an oxygen-enriched air duct, the oxygen-enriched air duct extending tangentially from the inlet cap.

Further examples of the air separation module may include that the inlet cap and the canister define between one another an annular oxygen collection plenum, the annular oxygen collection plenum fluidly coupling the separator with the oxygen-enriched air outlet port.

Further examples of the air separation module may include that the inlet cap has an inlet cap flange connecting the inlet cap to the canister, and further including a face seal member arranged axially between the inlet cap flange and the canister.

Further examples of the air separation module may include that the separator includes a resin body portion coupled to a canister portion by an inlet cap portion, the resin body portion and the canister portion of the separator contained within the inlet cap.

Further examples of the air separation module may include that the inlet cap portion of the separator is contained within the canister, and that the inlet cap portion of the separation is radially overlapped by the inlet cap.

Further examples of the air separation module may include that the separator includes a hollow fiber mat supported within the inlet cap by the resin body portion of the separator.

Further examples of the air separation module may include that the resin body portion of the separator is contained within the inlet cap and bounds an inlet cap plenum defined axially between the inlet cap and the resin body portion of the separator, and further that the air separation module further include a radial seal member radially compressed between the inlet cap and the resin body portion of the separator.

Further examples of the air separation module may include that the canister is a one-piece body including a perforated portion, the canister and the performed portion homogenous in composition and monolithic in construction.

Further examples of the air separation module may include a compressed air source fluidly coupled to the separator by the inlet cap, and therethrough disposed in fluid communication with the oxygen-enriched air outlet port.

Further examples of the air separation module may include that the canister has a perforated portion, the perforated portion of the canister fluidly coupling the separator with the oxygen-enriched air outlet port.

Further examples of the air separation module may include that the perforated portion of the canister is contained within the inlet cap.

An outlet cap is seated on the outlet end of the canister, wherein the outlet cap has an outlet cap axial length, wherein the inlet cap has an inlet cap axial length, and wherein the inlet cap axial length is greater than the outlet cap axial length.

Further examples of the air separation module may include that the canister has a canister inlet flange extending about the canister, the canister inlet flange connecting the inlet cap to the canister, the canister inlet flange arranged axially between the perforated portion of the canister and the outlet end of the canister.

Further examples of the air separation module may include that the canister contains a tube sheet locating feature, the tube sheet locating feature contained within the canister and radially separated from the inlet cap by the separator.

Further examples of the air separation module may include a fuel tank in fluid communication with the outlet end of the canister, the separator fluidly coupling the fuel tank to the inlet cap, the separator fluidly separating the fuel tank from the oxygen-enriched air outlet port.

Further examples of the air separation module may include that the canister has a canister inlet flange extending about the inlet end of the canister, that the canister has a canister outlet flange extending about the outlet end of the canister, and that the canister extends continuously and without a port between the canister inlet flange and the canister outlet flange.

A nitrogen generation system according to claim <NUM> is provided.

Further examples of the nitrogen generation system may include the canister has a perforated portion, the perforated portion of the canister fluidly coupling the separator with the oxygen-enriched air outlet port; and that the separator includes a resin body portion coupled to a canister portion by an inlet cap portion, the resin body portion and the canister portion of the separator contained within the inlet cap.

Further examples of the air separation module may include an ozone converter supported by the inlet cap; an inlet temperature sensor fluidly coupling the ozone converter to the separator; an oxygen sensor fluidly coupled to the inlet temperature sensor by the separator; an outlet temperature sensor fluidly coupled to the separator by the oxygen sensor; and a flow control valve fluidly coupled to the oxygen sensor by the outlet temperature sensor.

Technical effects of the present disclosure include air separation modules having relatively large oxygen-depleted air flow generating capacity (inerting capability) relative to space occupied by the air separation module. The air separation modules described herein have inlet caps that include an oxygen-enriched air output port. The air separation modules have inlet caps containing a portion of the separator, allowing the separator to be larger than the canister containing the separator. It is also contemplated that, in accordance with certain examples, air separation modules include canisters with perforated portions in communication with the oxygen-enriched air outlet port for diverting oxygen-enriched air, separated from compressed air received by the separator, to the ambient environment. Diversion can be accomplished, for example, via a collection annulus defined by the inlet cap.

Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an example of an air separation module constructed in accordance with the disclosure is shown in <FIG> and is designated generally by reference character <NUM>. Other examples of air separation modules, nitrogen generation systems, and methods of making air separation modules, are provided in <FIG>, as will be described. The systems and methods described herein can be used for generating oxygen-depleted (e.g., nitrogen-enriched) air flows for inerting fuel tanks, such as fuel tanks carried by aircraft, though the present disclosure is not limited to inerting fuel tanks on aircraft or to fuel systems in general.

Referring to <FIG>, a vehicle <NUM>, e.g., an aircraft is shown. The vehicle <NUM> includes a fuel system <NUM>, a compressed air source <NUM>, and a nitrogen generation system <NUM>. The nitrogen generation system <NUM> includes the air separation module <NUM>, a source conduit <NUM>, and a supply conduit <NUM>. The source conduit <NUM> fluidly connects the compressed air source <NUM> to the air separation module <NUM> to communicate a compressed air flow <NUM> to the air separation module <NUM>. The air separation module <NUM> is configured to separate an oxygen-depleted air flow fraction <NUM> from the compressed air flow <NUM>. The supply conduit <NUM> fluidly connects the air separation module <NUM> to the fuel system <NUM> to provide thereto the oxygen-depleted air flow fraction <NUM>. In certain examples the nitrogen generation system <NUM> is an onboard inert gas generation system (OBIGGS) for an aircraft.

The fuel system <NUM> includes a fuel tank <NUM>. The fuel tank <NUM> is fluidly coupled to the air separation module <NUM> by the supply conduit <NUM> and contains within its interior a liquid fuel <NUM>. The liquid fuel <NUM> and the interior of the fuel tank <NUM> define between one another an ullage space <NUM>. The ullage space <NUM> harbors an atmosphere with a mixture including a fuel vapor <NUM> and nitrogen <NUM>. The fuel vapor <NUM> is combustible in the presence of oxygen in concentration above a combustion threshold. The nitrogen <NUM> is provided by the oxygen-depleted air flow fraction <NUM> and is maintained in concentration sufficient to maintain concentration of oxygen with the ullage space below the combustion threshold of the fuel vapor <NUM>. Limiting oxygen concentration limits (or prevents entirely) possibility of combustion of the fuel vapor <NUM> in the event that an ignition source communicates with the fuel vapor <NUM>.

The compressed air source <NUM> is configured to provide the compressed air flow <NUM> (or pressurized air flow) using air ingested from the external environment <NUM>. In certain examples the compressed air source <NUM> includes an engine, such as the compressor section of gas turbine engine carried by an aircraft. In accordance with certain examples the compressed air source <NUM> includes an external compressed air source, such as a ground support equipment cart or facility compressed air source.

The nitrogen generation system <NUM> includes the air separation module <NUM>, a filter module <NUM> containing a debris filter <NUM> and an ozone converter <NUM>, and an inlet temperature sensor <NUM>. The nitrogen generation system <NUM> also includes an outlet temperature sensor <NUM>, an oxygen sensor <NUM>, and a flow control valve <NUM>.

The filter module <NUM> fluidly couples the source conduit <NUM> to the inlet temperature sensor <NUM> to communicate thereto the compressed air flow <NUM>. The debris filter <NUM> is configured to impound debris entrained within the compressed air flow <NUM>. The ozone converter <NUM> is also to convert ozone molecules included within the compressed air flow <NUM> into dioxygen molecules, preventing the entrained ozone molecules from reaching the air separation module <NUM>. As will be appreciated by those of skill in the art in view of the present disclosure, entrained debris and/or ozone can limit the reliability of the air separation module <NUM>.

The inlet temperature sensor <NUM> is configured to measure temperature of the compressed air flow <NUM> provided to the air separation module <NUM>. In this respect the inlet temperature sensor <NUM> fluidly couples the filter module <NUM> to the air separation module <NUM> for measuring temperature of the compressed air flow <NUM> received from the supply conduit <NUM> via the filter module <NUM> subsequent to filtering and ozone conversion. In certain examples the inlet temperature sensor <NUM> is disposed in communication with a controller, which adjusts temperature of the compressed air flow <NUM> to maintain the compressed air flow <NUM> within a predetermined inlet temperature range.

The air separation module <NUM> includes a separator <NUM>. The separator <NUM> is configured to separate the compressed air flow <NUM> into the oxygen-depleted air flow fraction <NUM> and an oxygen-enriched air flow fraction <NUM>. The oxygen-enriched air flow fraction <NUM> is diverted from the fuel system <NUM> by the air separation module <NUM>, e.g., is dumped overboard. The oxygen-depleted air flow fraction <NUM> is communicated by the air separation module <NUM> to the fuel system <NUM> via the outlet temperature sensor <NUM>, the oxygen sensor <NUM>, and the flow control valve <NUM>. In certain examples the separator <NUM> includes a hollow fiber mat <NUM> (shown in <FIG>) configured to separate the compressed air flow <NUM> into the oxygen-depleted air flow fraction <NUM> and the oxygen-enriched air flow fraction <NUM>. Examples of suitable hollow fiber mats include PEEK-Sep™ hollow fiber mats, available from Air Liquide Advanced Separations of Woburn, Massachusetts.

The outlet temperature sensor <NUM> is configured to measure temperature of the oxygen-depleted air flow fraction <NUM> prior to the oxygen-depleted air flow fraction <NUM> reaching the fuel system <NUM>. In this respect the outlet temperature sensor <NUM> fluidly couples the air separation module <NUM>, and therein the separator <NUM>, to the oxygen sensor <NUM> to measure temperature of the oxygen-depleted air flow fraction <NUM>. It is contemplated the outlet temperature sensor <NUM> provide a signal to a controller indicative of temperature of the oxygen-depleted air flow fraction <NUM>, the controller thereby able to control of the oxygen-depleted air flow fraction <NUM> communicated to the fuel system <NUM>.

The oxygen sensor <NUM> is configured to measure concentration of oxygen within the oxygen-depleted air flow fraction <NUM> prior to the oxygen-depleted air flow fraction <NUM> reaching the fuel system <NUM>. In this respect the oxygen sensor <NUM> fluidly couples the outlet temperature sensor <NUM> to the flow control valve <NUM>, and therethrough to the supply conduit <NUM>, to measure oxygen concentration within the oxygen-depleted air flow fraction <NUM> received from the separator <NUM> as the oxygen-depleted air flow fraction <NUM> traverses the air separation module <NUM>. It is contemplated that the oxygen sensor <NUM> provide a signal to a controller indicative of oxygen concentration within the oxygen-depleted air flow fraction <NUM>, the controller thereby able to monitor performance of the air separation module <NUM>.

The flow control valve <NUM> is configured to control flow rate, e.g., mass flow rate, of the oxygen-depleted air flow fraction <NUM> to the supply conduit <NUM>. In this respect the flow control valve <NUM> fluidly couples the oxygen sensor <NUM> to the supply conduit <NUM> throttle flow of the oxygen-depleted air flow fraction <NUM> to the fuel system <NUM>. It is contemplated that the flow control valve <NUM> be operatively associated with a controller to throttle the flow rate of the oxygen-depleted air flow fraction <NUM> according to the inerting requirements of the fuel system <NUM> and/or according to the operating requirements of the vehicle <NUM>.

As will be appreciated by those of skill in the art in view of the present disclosure, the inerting capability provided by air separation modules generally corresponds to the weight and size of the air separation module. To limit weight and size per unit inerting capability the air separation module <NUM> is provided.

The air separation module <NUM> generally includes the separator <NUM>, a canister <NUM> (shown in <FIG>), and an inlet cap <NUM> (shown in <FIG>). The canister <NUM> has an inlet end <NUM> and an outlet end <NUM> arranged along a canister axis <NUM> (shown in <FIG>). The separator <NUM> is supported within the canister <NUM> and is arranged to separate a compressed air flow, e.g., the compressed air flow <NUM>, received at the air separation module <NUM> into an oxygen-depleted air flow fraction, e.g., the oxygen-depleted air flow fraction <NUM>, and an oxygen-enriched air flow fraction, e.g., the oxygen-enriched air flow fraction <NUM>. The inlet cap <NUM> (e.g., an inlet end cap) is seated about the inlet end <NUM> of the canister <NUM>, contains therein a portion <NUM> (shown in <FIG>) of the separator <NUM> and has an oxygen-enriched air outlet port <NUM>. The oxygen-enriched air outlet port <NUM> is fluidly separated from the outlet end <NUM> of the canister <NUM> by the separator <NUM> for diverting the oxygen-enriched air flow fraction to the external environment <NUM>.

With reference to <FIG>, the air separation module <NUM> includes the canister <NUM>, the inlet cap <NUM>, and an outlet cap <NUM> (e.g., an outlet end cap). The canister <NUM> defines the canister axis <NUM> and has canister inlet flange <NUM>, and a canister outlet flange <NUM>. The canister inlet flange <NUM> extends about the canister <NUM>. The canister inlet flange <NUM> extends about the inlet end <NUM> of the canister <NUM>. The canister outlet flange <NUM> extends about the outlet end <NUM> of the outlet end <NUM> of the canister <NUM>. The canister <NUM> has no oxygen-enriched air outlet port defined between the canister inlet flange <NUM> and the canister outlet flange <NUM>, the oxygen-enriched air outlet port <NUM> instead defined by the inlet cap <NUM>. In the illustrated example the canister <NUM> has a band <NUM>, e.g., a doubler) with a canister fixation feature <NUM> extending laterally therefrom arranged between the canister inlet flange <NUM> and the canister outlet flange <NUM> for fixation of the air separation module <NUM> to vehicle structure, e.g., the vehicle <NUM> (shown in <FIG>), through the canister <NUM>.

The outlet cap <NUM> has an output cap flange <NUM> and an output cap fixation feature <NUM>. The output cap flange <NUM> connects the outlet cap <NUM> to the canister outlet flange <NUM> and therethrough to the canister <NUM>. The output cap fixation feature <NUM> extends laterally from the outlet cap <NUM> and is arranged for fixation of the air separation module <NUM> to vehicle structure, e.g., the vehicle <NUM> (shown in <FIG>), through the outlet cap <NUM>. In the illustrated example the oxygen sensor <NUM>, outlet temperature sensor <NUM>, and the flow control valve <NUM> are each supported by the outlet cap <NUM>. In this respect the output cap flange <NUM> of the outlet cap <NUM> and the canister outlet flange <NUM> of the canister <NUM> cooperate to communicate the load of the canister <NUM>, the outlet cap <NUM>, the oxygen sensor <NUM>, the outlet temperature sensor <NUM>, and the flow control valve <NUM> through the canister fixation feature <NUM> and the outlet cap fixation feature <NUM>.

The inlet cap <NUM> is similar the outlet cap <NUM> and additionally has an inlet cap flange <NUM>, an oxygen-enriched air duct <NUM>, a filter module mount <NUM>, and an inlet cap fixation feature <NUM>. The inlet cap flange <NUM> connects the inlet cap <NUM> to the canister inlet flange <NUM> and therethrough to the canister <NUM>. The filter module mount <NUM> supports the filter module <NUM> and fluidly couples the filter module <NUM> to the canister <NUM>. The inlet cap fixation feature <NUM> extends laterally from the inlet cap <NUM> and is arranged for fixation of the air separation module <NUM> to vehicle structure, e.g., the vehicle <NUM> (shown in <FIG>), through the inlet cap <NUM>. It is contemplated that the filter module <NUM> be supported by the inlet cap <NUM>, e.g., cantilevered therefrom, a portion of the load associated with the filter module <NUM> communicated through the inlet cap flange <NUM> and the canister inlet flange <NUM>.

The oxygen-enriched air duct <NUM> extends tangentially from the inlet cap <NUM> and defines the oxygen-enriched air outlet port <NUM>. In certain examples the inlet cap <NUM> and oxygen-enriched air duct <NUM> are monolithically formed as a one-piece body of homogeneous composition, e.g., as a casting or as an additively manufactured article, simplifying assembly of the air separation module. In accordance with certain examples the inlet cap <NUM>, the oxygen-enriched air duct <NUM>, and the filter module mount <NUM> can be monolithically formed as a one-piece body of homogenous composition, e.g., as a casting or as an additively manufactured article, further simplifying assembly of the air separation module <NUM>. As shown in <FIG> the inlet cap <NUM> has an inlet cap axial length <NUM> that is greater than an outlet cap axial length <NUM> of the outlet cap <NUM>, the inlet cap <NUM> thereby arranged to contain therein a portion of the separator <NUM>. This increases the volume within the air separation module <NUM> available for the separator <NUM> for a given canister length between the canister inlet flange <NUM> and the canister outlet flange <NUM>.

With reference to <FIG>, a portion of the air separation module <NUM> including the inlet cap <NUM> and the canister <NUM> is shown. The separator <NUM> includes a resin body portion <NUM>, an inlet cap portion <NUM>, and a canister portion <NUM>. The canister portion <NUM> is contained within the canister <NUM> and is connected to the resin body portion <NUM> by the inlet cap portion <NUM>. The inlet cap portion <NUM> of the separator <NUM> is contained within the canister <NUM>, is further contained within the inlet cap <NUM>, and couples the canister portion <NUM> of the separator <NUM> to the resin body portion <NUM> of the separator <NUM>. The resin body portion <NUM> extends axially from the canister <NUM> in the direction of the filter module mount <NUM>, is contained within the inlet cap <NUM> and bounds an inlet cap plenum <NUM> defined between the resin body portion <NUM> and the inlet cap <NUM>. In certain examples the resin body portion <NUM> provides structural support to the hollow fiber mat <NUM> of the separator <NUM>, e.g., by presenting a machined surface to the inlet cap plenum <NUM> through which hollow fibers of the hollow fiber mat <NUM> fluidly communicate with the inlet cap plenum <NUM>. In accordance the certain examples the canister <NUM> contains a tube sheet locating feature <NUM>, the tube sheet locating feature <NUM> contained within the canister <NUM> and radially separated from the inlet cap <NUM> by the separator <NUM> to axially fix the separator relative to the canister <NUM>.

The canister <NUM> is partially contained with the inlet cap <NUM> and this respect has an inter-flange portion <NUM>, a perforated portion <NUM>, and rim portion <NUM>. The inter-flange portion <NUM> of the canister <NUM> extends between the canister outlet flange <NUM> (shown in <FIG>) and the canister inlet flange <NUM>. The perforated portion <NUM> of the canister <NUM> extends axially from inter-flange portion <NUM> of the canister <NUM> in a direction opposite the canister inlet flange <NUM>, connects the inter-flange portion <NUM> of the canister <NUM> to the rim portion <NUM> of the canister <NUM>, and has a plurality of perforations <NUM> extending radially therethrough. In certain examples canister <NUM> is a one-piece body including the perforated portion <NUM>, the canister both homogenous in composition and monolithic in construction to provide structural strength to the canister <NUM>.

The plurality of perforations <NUM> fluidly couple the separator <NUM> with the oxygen-enriched air outlet port <NUM> through the oxygen-enriched air duct <NUM> (shown in <FIG>), and in the illustrated example are distributed circumferentially about the circumference of the canister <NUM>. The rim portion <NUM> of the canister <NUM> extends axially from the perforated portion <NUM> of the canister <NUM> in a direction axially opposite the canister inlet flange <NUM>, is contained within the inlet cap <NUM> and is connected to the inter-flange portion <NUM> of the canister <NUM>. In the illustrated example both the perforated portion <NUM> of the canister <NUM> and the rim portion <NUM> of the canister <NUM> are radially overlapped by the inlet cap <NUM>, the perforated portion <NUM> and the rim portion <NUM> thereby cooperating with the resin body portion <NUM> of the separator <NUM> to support and protect the hollow fiber mat <NUM> during assembly of the inlet cap <NUM> on the canister <NUM>.

The inlet cap <NUM> defines a radial seal slot <NUM>, a canister seat <NUM>, an annular oxygen collection plenum <NUM>, and a face seal slot <NUM>. The radial seal slot <NUM> extends circumferentially about an interior surface <NUM> of the inlet cap <NUM>, is defined axially between inlet cap plenum <NUM> and the canister seat <NUM>, and seats therein a radial seal member <NUM>. The radial seal member <NUM> is radially compressed between the resin body portion <NUM> of the separator <NUM> and the interior surface <NUM> of the inlet cap <NUM> to fluidly separate the oxygen-enriched air outlet port <NUM> from the inlet cap plenum <NUM>. The canister seat <NUM> is defined by the interior surface <NUM> of the inlet cap <NUM>, extends circumferentially about the rim portion <NUM> of the canister <NUM> and radially outward thereof, and receives therein the rim portion <NUM> of the canister <NUM>.

The annular oxygen collection plenum <NUM> is defined between the interior surface <NUM> of the inlet cap <NUM> and the separator <NUM>, and more particularly between the interior surface <NUM> of the inlet cap <NUM> and the perforated portion <NUM> of the canister <NUM>, and fluidly couples the separator <NUM> to the oxygen-enriched air outlet port <NUM> of the inlet cap <NUM>. The face seal slot <NUM> is defined within an axial face <NUM> of the inlet cap flange <NUM>, extends circumferentially about the separator <NUM>, and seats therein a face seal member <NUM>. The face seal member <NUM> is axially compressed between the canister inlet flange <NUM> and the inlet cap flange <NUM>, the face seal member <NUM> thereby fluidly separating the annular oxygen collection plenum <NUM> from the external environment <NUM> (shown in <FIG>) and thereby limiting fluid communication between the annular oxygen collection plenum <NUM> and the external environment <NUM> to the oxygen-enriched air outlet port <NUM>.

During operation the compressed air flow <NUM> (shown in <FIG>) enters the inlet cap plenum <NUM> through the filter module mount <NUM>. The inlet cap plenum <NUM> communicates the compressed air flow <NUM> to the separator <NUM>, e.g., to hollow fibers of the hollow fiber mat <NUM>. The hollow fibers convey the compressed air flow <NUM> through the resin body portion <NUM> of the separator <NUM> and therethrough to the canister portion <NUM> of the separator <NUM>. As the compressed air flow <NUM> traverses the canister portion <NUM> of the separator <NUM> oxygen molecules of the compressed air flow traverse (e.g., driven by pressure) walls of the hollow fibers and collect in the annular oxygen collection plenum <NUM>. The annular oxygen collection plenum <NUM> diverts the oxygen molecules to the external environment <NUM> (shown in <FIG>) as the oxygen-enriched air flow fraction <NUM> (shown in <FIG>) through the oxygen-enriched air outlet port <NUM>. The hollow fibers of the hollow fiber mat <NUM> in turn convey nitrogen molecules of the compressed air flow <NUM> to the outlet end <NUM> of the canister <NUM>, and therethrough to the fuel tank <NUM> (shown in <FIG>) as the oxygen-depleted air flow fraction <NUM> (shown in <FIG>) wherein the oxygen-depleted air flow fraction <NUM> limits concentration of oxygen within the ullage space <NUM> (shown in <FIG>) of the fuel tank <NUM>.

With reference to <FIG>, a method <NUM> of making an air separation module, e.g., the air separation module <NUM> (shown in <FIG>), is shown. The method includes defining a canister with an inlet end and an outlet end arranged along a canister axis, e.g., the canister <NUM> (shown in <FIG>) with the inlet end <NUM> (shown in <FIG>) and the outlet end <NUM> (shown in <FIG>) arranged along the canister axis <NUM> (shown in <FIG>), as shown with box <NUM>. The method <NUM> also includes supporting a separator within the canister, e.g., the separator <NUM> (shown in <FIG>), as shown with box <NUM>. It is contemplated that separator be arranged to separate a compressed air flow, e.g., the compressed air flow <NUM> (shown in <FIG>), into an oxygen-depleted air flow fraction and an oxygen-enriched air flow fraction, e.g., the oxygen-depleted air flow fraction <NUM> (shown in <FIG>) and the oxygen-enriched air flow fraction <NUM> (shown in <FIG>), as also shown with box <NUM>.

As shown with box <NUM>, an inlet cap is seated about the inlet end of the canister, e.g., the inlet cap <NUM> (shown in <FIG>). It is contemplated that the inlet cap contains a portion of the separator, e.g., the resin body portion <NUM> (shown in <FIG>) of the separator <NUM> (shown in <FIG>) and the inlet cap portion <NUM> (shown in <FIG>) of the separator <NUM>, as also shown with box <NUM>. In certain examples seating the inlet cap on the canister includes defining an annular oxygen collection plenum between the canister and the inlet cap, e.g., the annular oxygen collection plenum <NUM>, as shown with box <NUM>.

As shown with box <NUM>, the method <NUM> also includes fluidly separating an oxygen-enriched air outlet port, e.g., the oxygen-enriched air outlet port <NUM> (shown in <FIG>), from the outlet end of the canister using the separator for diverting the oxygen-enriched air flow fraction to the external environment. In certain examples fluidly separating the oxygen-enriched air outlet port from the outlet end of the canister includes compressing a face seal member, e.g., the face seal member <NUM> (shown in <FIG>), axially between the canister and inlet cap, as shown with box <NUM>. In accordance with certain examples fluidly separating the oxygen-enriched air outlet port from the outlet end of the canister includes compressing a radial seal member, e.g., the radial seal member <NUM> (shown in <FIG>), radially between the canister and the separator and the inlet cap, as shown with box <NUM>. As shown with box <NUM> the separator is thereafter fluidly coupled with the oxygen-enriched air outlet port using the annular oxygen collection plenum, as shown with box <NUM>.

Fuel tanks, such as fuel tanks used to store liquid fuel in vehicles like aircraft, commonly contain fuel vapors within the ullage space of the fuel tank. Because such fuel vapors can present a fire hazard some vehicles include nitrogen generation systems with air separation modules. The air separation module is typically arranged to provide a flow of oxygen-depleted air to the fuel tank ullage space, limiting concentration of oxygen within the fuel tank ullage space and reducing (or eliminating entirely) the fire hazard potentially posed by the fuel vapors. The volume of nitrogen enriched air is generally constrained by the size of the air separation module and space allocated to the air separation module within the vehicle.

In examples provided herein air separation modules are provided having an inlet cap with an oxygen-enriched air outlet port. Portions of the canister and the separator are contained within the inlet cap and the canister perforated to provide fluid communication between the separator and the external environment. The fluid communication provided by the perforated portion of the canister allows oxygen-enriched air driven out of the separator by pressure of compressed air admitted to the separator to exit the air separation module through the inlet cap through oxygen-enriched air outlet port.

The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting of the present disclosure.

Claim 1:
An air separation module, comprising:
a canister (<NUM>), comprising an inlet end (<NUM>) and an outlet end (<NUM>), arranged along a canister axis (<NUM>);
a separator (<NUM>) supported within the canister and arranged to separate a compressed air flow received at the air separation module into an oxygen-depleted air flow fraction and an oxygen-enriched air flow fraction;
a filter module;
an inlet cap (<NUM>) seated about the inlet end of the canister and containing therein a portion of the separator, wherein the inlet cap (<NUM>) includes :
a filter module mount (<NUM>) that supports the filter module (<NUM>) and fluidly couples the filter module with the canister, and an oxygen-enriched air outlet port (<NUM>) fluidly separated from the outlet end of the canister by the separator for diverting the oxygen-enriched air flow fraction to an external environment; and
an outlet cap (<NUM>) seated on the outlet end of the canister, wherein the outlet cap has an outlet cap axial length, wherein the inlet cap has an inlet cap axial length, and wherein the inlet cap axial length is greater than the outlet cap axial length to contain therein a portion of the separator.