Patent Description:
In some configurations of turbo electric (hybrid) airplane propulsion systems, the electric units such as generators or motors can be located next to the thermal engines. The electrical system can require efficient cooling, and the cooling system can be required in a difficult location in the fuselage. <CIT> relates to a system to produce aircraft cabin supply air. <CIT> relates to a generator with air-cycle cooling.

The present disclosure provides air cooling systems and methods for propulsion systems (e.g., aviation or aerospace propulsion systems). More particularly, the present disclosure provides integrated air cooling systems and methods utilizing air cycle machine cooling for hybrid-electric aircraft or aerospace propulsion systems or the like.

The present disclosure provides for an air cooling system including a compressed air source for a thermal combustor as claimed in claim <NUM>. The thermal combustor in communication with a turbine; and an electric motor or generator in communication with an electric turbine; wherein a portion of air is configured to be directed from the compressed air source to a heat exchanger and then to the electric turbine; and wherein a portion of expanded air is configured to be directed from the electric turbine to the electric motor for cooling of the electric motor.

In addition to one or more of the features described, the thermal combustor and the electric motor or generator are included in a hybrid-electric aircraft or aerospace propulsion system.

In addition to one or more of the features described, the compressed air source is driven by the thermal combustor, or driven by the electric motor or generator.

In addition to one or more of the features described, the heat exchanger is a skin integrated heat exchanger, and the portion of air directed to the heat exchanger is cooled via outside or ambient air flow.

In addition to one or more of the features described, the portion of expanded air is configured to be directed to a water separator prior to being directed to the electric motor or generator for cooling of the electric motor or generator.

In addition to one or more of the features described, wherein a first portion of expanded and water separated air is configured to be directed from the water separator to the electric motor or generator for cooling of the electric motor or generator, and a second portion of expanded and water separated air is configured to be utilized as an air supply for cabin or cargo air cycle cooling of an aircraft or aerospace system.

In addition to one or more of the features described, the portion of expanded air is configured to be directed to a cooling jacket of the electric motor or generator for cooling of the electric motor or generator.

In addition to one or more of the features described, the portion of expanded air is configured to be directed to a plurality of hollow wires for cooling of the electric motor or generator.

In addition to one or more of the features described, the plurality of hollow wires are fabricated via additive manufacturing.

Discharged air from the cooled electric motor or generator is configured to be directed to the thermal combustor.

The present disclosure provides for an air cooling method as claimed in claim <NUM> including providing a compressed air source for a thermal combustor, the thermal combustor in communication with a turbine; and providing an electric motor or generator in communication with an electric turbine; and directing a portion of air from the compressed air source to a heat exchanger and then to the electric turbine; and directing a portion of expanded air from the electric turbine to the electric motor for cooling of the electric motor.

In addition to one or more of the features described, the portion of expanded air is directed to a water separator prior to being directed to the electric motor or generator for cooling of the electric motor or generator.

In addition to one or more of the features described, wherein a first portion of expanded and water separated air is directed from the water separator to the electric motor or generator for cooling of the electric motor or generator, and a second portion of expanded and water separated air is utilized as an air supply for cabin or cargo air cycle cooling of an aircraft or aerospace system.

In addition to one or more of the features described, the portion of expanded air is directed to a cooling jacket of the electric motor or generator for cooling of the electric motor or generator.

In addition to one or more of the features described, the portion of expanded air is directed to a plurality of hollow wires for cooling of the electric motor or generator.

Discharged air from the cooled electric motor or generator is directed to the thermal combustor.

Additional features, functions and applications of the disclosed assemblies, systems and methods of the present disclosure will be apparent from the description which follows, particularly when read in conjunction with the appended figures.

With reference to the accompanying drawings, like elements are numbered alike.

Features and aspects of embodiments are described below with reference to the accompanying drawings, in which elements are not necessarily depicted to scale.

Example embodiments of the present disclosure are further described with reference to the appended figures. It is to be noted that the various features, steps, and combinations of features/steps described below and illustrated in the figures can be arranged and organized differently to result in embodiments which are still within the scope of the present disclosure. To assist those of ordinary skill in the art in making and using the disclosed assemblies, systems and methods, reference is made to the appended figures, wherein:.

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the figures.

The example embodiments disclosed herein are illustrative of air cooling systems, and assemblies of the present disclosure and methods/techniques thereof. It should be understood, however, that the disclosed embodiments are merely examples of the present disclosure, which may be embodied in various forms. Therefore, details disclosed herein with reference to example air cooling systems and assemblies and associated processes/techniques of fabrication/assembly and use are not to be interpreted as limiting, but merely as the basis for teaching one skilled in the art how to make and use the assemblies/systems and/or alternative assemblies/systems of the present disclosure.

Current practice provides that electrical components of turbo electric (hybrid) airplane propulsion systems can require efficient cooling, and such electrical components can be positioned in a difficult location (e.g., next to the thermal engines, etc.). The present disclosure provides integrated air cycle machine cooling into the hybrid propulsion system (e.g., into the wing-mounted hybrid propulsion system). As such, the air cooling systems and methods of the present disclosure can minimize weight while improving electric motor/generator cooling.

<FIG> is a schematic of an example air cooling system <NUM> for propulsion systems (e.g., aviation or aerospace propulsion systems), according to certain embodiments of the present disclosure.

In certain embodiments and as shown in <FIG>, system <NUM> is an integrated air cooling system <NUM> that utilizes air cycle machine cooling for hybrid-electric aircraft or aerospace propulsion systems or the like, as discussed further below.

As shown in <FIG>, a portion of air <NUM> can be diverted or directed from a compressed air source <NUM> for thermal combustor <NUM> of system <NUM>. The portion of air <NUM> can be directed to heat exchanger <NUM>, as discussed further below.

In example embodiments, the compressed air source <NUM> includes a high pressure compressor <NUM>, and high pressure compressor <NUM> can be in communication with low pressure compressor <NUM> of system <NUM>. Thermal combustor <NUM> can be in communication with high pressure turbine <NUM> and low pressure turbine <NUM> of the hybrid-electric aircraft or aerospace propulsion and cooling system <NUM>. It is noted that condensed water can be injected into the combustor <NUM> or high pressure turbine <NUM> to improve performance.

It is noted that the compressed air source <NUM> (e.g., high pressure compressor <NUM>) can be driven from the thermal combustor <NUM> (e.g., including geared arrangement), or driven by the electric motor or generator <NUM> of the hybrid-electric aircraft or aerospace propulsion and cooling system <NUM>. During ground operation, the motor/generator <NUM> of the system works in generator mode. Power from a low-pressure spool shaft is transferred by a power take off shaft arrangement, to provide mechanical power to the generator <NUM>. The generator <NUM> produces electrical power and by suitable power conversion that power is used for electrical load, including battery charging. During takeoff, additional thrust can be desired. The motor/generator <NUM> of the system works in motor mode. During this mode, electrical power from a battery, through suitable power conversion and inversion, is used to provide electrical power to the motor <NUM>. The motor <NUM> provides power to the low-pressure spool that includes a propulsion fan, low pressure compressor <NUM> and low-pressure turbine <NUM>. In this manner additional thrust is provided to the low-pressure spool during takeoff mode. During cruise mode, the motor/generator <NUM> of the system works in generator mode and produces electrical power for electrical load including battery charging. During the motor mode as well as generator mode, some portion of the shaft power is used to expand compressed and cooled air in the electric turbine <NUM>.

In some embodiments not belonging to the claimed subject matter and as shown in <FIG>, the system <NUM> utilizes a turbine-driven booster compressor. In such case, the turbine <NUM> is not being mechanically linked to the motor <NUM>, but works as a stand-alone turbine unit <NUM> connected to the compressor <NUM> or <NUM>. In other embodiments, the turbine <NUM> is connected to the motor <NUM> via a gear <NUM> or the like (e.g. mechanical gear, magnetic gear, hydraulic gear, ferrofluidic gear, etc.).

As noted, a portion of air <NUM> can be diverted or directed from a compressed air source <NUM> and can be directed to heat exchanger <NUM>. In an example embodiment, heat exchanger is a nacelle skin integrated heat exchanger <NUM>, and the air <NUM> is cooled via outside or ambient air flow <NUM>. In other embodiments, other suitable types of heat exchangers <NUM> can be utilized to cool air <NUM>.

Cooled air <NUM> then exits the heat exchanger <NUM> and is expanded in the electric turbine <NUM> of the hybrid-electric aircraft or aerospace propulsion and cooling system <NUM>. In some embodiments, the expanded air <NUM> can then be passed through an optional water separator <NUM>.

A first portion of expanded and water separated air <NUM> can be directed from water separator <NUM> and passed through a cooling jacket <NUM> of the electric motor or generator <NUM> for cooling of the electric motor/generator <NUM>. In some embodiments, the cooling jacket <NUM> can be fabricated via additive manufacturing, as discussed further below. In certain embodiments, cooling jacket <NUM> is positioned around the stator <NUM> of electric motor or generator <NUM> (<FIG>). In other embodiments, cooling air is directed to cool hollow wire <NUM> winding end turns, in addition to cooling jacket <NUM> (e.g., pure copper hollow wiring; hollow wiring fabricated via additive manufacturing, etc.) for the cooling of electric motor/generator <NUM> (<FIG>). It is noted that condensed water can be utilized as a complement for additional motor <NUM> cooling.

After cooling the electric motor/generator <NUM>, discharged air <NUM> can be returned to thermal combustor <NUM> or some other location (e.g., turbines <NUM> and/or <NUM>).

A second portion of expanded and water separated air <NUM> can be directed from water separator <NUM> and passed to other aircraft/aerospace locations of system <NUM> as an air supply <NUM> (e.g., air supply <NUM> for cabin/cargo air cycle machine cooling of other aircraft/aerospace locations of system <NUM>).

As shown in <FIG>, the electric motor <NUM> can include a cooling jacket <NUM> having a plurality of cooling channels <NUM>.

As shown in <FIG>, the electric motor <NUM> can include conventional or additively manufactured (e.g., 3D printed) hollow wires <NUM> (e.g., hollow wires <NUM> having any suitable cross-section, such as oval, circular, etc.). The hollow wires <NUM> can be configured for internal or external coolant flow (e.g., hydrochlorofluorocarbon refrigerant flow) for cooling electric motor <NUM>. In one configuration, dielectric coolant can flow through the hollow wires <NUM> to remove heat from the copper wire <NUM>. Absorbed heat from dielectric coolant is removed by an air cooled heat exchanger disposed on the generator/motor <NUM> outer surface. In another configuration, the hollow wires <NUM> can be sealed at both ends and work as a heat pipe where heat is transferred by evaporation at the warmer end of the wire <NUM> and condensation forms at the cooler end of the wire <NUM>. The cooler end of the wire <NUM> is the end that is directly cooled by air flowing over it, preferably at the end winding <NUM>.

There are many benefits of the systems <NUM>, assemblies and methods of the present disclosure, including, without limitation: lower weight and high/improved reliability of air cycle cooling system <NUM>; additively created hollow wire <NUM> profile can be optimized for improved magneto-electric and/or thermal properties of motor <NUM>; and/or higher power to weight ratio electric units of system <NUM> can be constructed/utilized.

The ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other (e.g., ranges of "up to <NUM> wt. %, or, more specifically, <NUM> wt. % to <NUM> wt. %", is inclusive of the endpoints and all intermediate values of the ranges of "<NUM> wt. % to <NUM> wt. "Combinations" is inclusive of blends, mixtures, alloys, reaction products, and the like. The terms "first," "second," and the like, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. "Or" means "and/or" unless clearly stated otherwise.

Although the assemblies, systems and methods of the present disclosure have been described with reference to example embodiments thereof, the present disclosure is not limited to such example embodiments and/or implementations. Rather, the assemblies, systems and methods of the present disclosure are susceptible to many implementations and applications, as will be readily apparent to persons skilled in the art from the disclosure hereof. The present disclosure expressly encompasses such modifications, enhancements and/or variations of the disclosed embodiments.

Claim 1:
An air cooling system (<NUM>) comprising:
a compressed air source (<NUM>) for a thermal combustor (<NUM>), the thermal combustor in communication with a turbine; and
an electric motor or generator (<NUM>) in communication with an electric turbine (<NUM>);
wherein the air cooling system is configured to direct a portion of air from the compressed air source to a heat exchanger (<NUM>) and then to the electric turbine; and
wherein the air cooling system is configured to direct a portion of expanded air from the electric turbine to the electric motor or generator for cooling of the electric motor or generator;
characterised in that the air cooling system is configured to direct discharged air from the cooled electric motor or generator (<NUM>) to the thermal combustor (<NUM>).