Hybrid aircraft propulsors having electrically-driven augmentor fans are disclosed. An example apparatus includes a turbofan having a core engine and a ducted fan to be rotated via the core engine. The ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. The example apparatus further includes an augmentor fan having an augmentor hub ring and a plurality of augmentor fan blades. The augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. The augmentor fan is to rotate separately from the ducted fan. The example apparatus further includes an electrical drive to rotate the augmentor hub ring in response to a supply of electrical energy provided to the electrical drive.

FIELD OF THE DISCLOSURE

This disclosure relates generally to aircraft propulsors having augmentor fans and, more particularly, to hybrid aircraft propulsors having electrically-driven augmentor fans.

BACKGROUND

Turbofan aircraft engines may be equipped with augmentor fans to increase a bypass ratio of the turbofan while maintaining the benefit of a reduction in noise attributable to the turbofan being shrouded (e.g., via a nacelle surrounding a ducted fan of the turbofan). Example aircraft propulsors having mechanically-driven augmentor fans are disclosed in U.S. Pat. No. 8,689,538, issued on Apr. 8, 2014, entitled “Ultra-Efficient Propulsor with an Augmentor Fan Circumscribing a Turbofan.” Example aircraft propulsors having air-driven augmentor fans are disclosed in U.S. Patent Publication No. 2017/0122257, published on May 4, 2017, entitled “Nacelle-Integrated Air-Driven Augmentor Fan for Increasing Propulsor Bypass Ratio and Efficiency.” U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257 are hereby incorporated by reference herein in their entireties.

SUMMARY

Hybrid aircraft propulsors having electrically-driven augmentor fans are disclosed. In some examples, an apparatus is disclosed. In some disclosed examples, the apparatus comprises a turbofan including a core engine and a ducted fan to be rotated via the core engine. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the apparatus further comprises an augmentor fan including an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the augmentor fan is to rotate separately from the ducted fan. In some disclosed examples, the apparatus further comprises an electrical drive to rotate the augmentor hub ring in response to a supply of electrical energy provided to the electrical drive.

In some examples, an apparatus is disclosed. In some disclosed examples, the apparatus comprises a turbofan including a core engine and a ducted fan to be rotated via the core engine. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the apparatus further comprises an augmentor fan including an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the augmentor fan is to rotate separately from the ducted fan. In some disclosed examples, the apparatus further comprises means for driving the augmentor hub ring to rotate in response to a supply of electrical energy provided to the means for driving.

In some examples, a method is disclosed. In some disclosed examples, the method comprises rotating a ducted fan of a turbofan via a core engine of the turbofan. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the method further comprises rotating an augmentor fan via an electrical drive in response to a supply of electrical energy provided to the electrical drive. In some disclosed examples, the augmentor fan includes an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the rotating of the augmentor fan is separate from the rotating of the ducted fan.

Certain examples are shown in the above-identified figures and described in detail below. In describing these examples, like or identical reference numbers are used to identify the same or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic for clarity and/or conciseness.

DETAILED DESCRIPTION

Turbofan aircraft engines equipped with augmentor fans provide several advantages relative to conventional turbofan engines. For example, incorporating an augmentor fan into a conventional turbofan engine increases a bypass ratio and reduces a fan pressure ratio of the turbofan engine while maintaining the benefit of a reduction in noise attributable to the turbofan engine being shrouded (e.g., via a nacelle surrounding a ducted fan of the turbofan engine). The increased bypass ratio and reduced fan pressure ratio attributable to the augmentor fan advantageously improves the fuel efficiency and reduces the operating costs associated with the modified turbofan engine relative to the fuel efficiency and operating costs associated with the conventional turbofan engine. Such advantages may be provided, for example, by the aircraft propulsors having mechanically-driven and/or air-driven augmentor fans disclosed in U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257, as referenced above.

Unlike the aircraft propulsors having mechanically-driven and/or air-driven augmentor fans as described in U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257, the hybrid aircraft propulsors disclosed herein include electrically-driven augmentor fans. As a result of being powered by electrical energy as opposed to jet fuel, the disclosed electrically-driven augmentor fans advantageously provide even further increases in fuel efficiency and reductions in operating costs relative to the above-referenced mechanically-drive and/or air-driven augmentor fans. The disclosed hybrid propulsors and/or electrically-driven augmentor fans also advantageously provide environmental benefits such as reduced carbon emissions.

The hybrid propulsors and/or electrically-driven augmentor fans disclosed herein advantageously leverage electrical energy produced and/or stored by conventional electrical energy sources of an aircraft. For example, the disclosed electrically-driven augmentor fans may receive a supply of electrical energy generated by an electrical generator of an auxiliary power unit and/or by an electrical generator of a gas turbine of an aircraft implementing the disclosed hybrid propulsors. The disclosed electrically-driven augmentor fans may additionally or alternatively receive a supply of electrical energy from one or more electrical energy storage device(s) of the aircraft, including, for example, a battery, a flywheel, and/or a supercapacitor.

As a result of being powered by an electrical energy source as opposed to being powered through a mechanical drive train, an electrically-driven augmentor fan of the disclosed hybrid propulsors is separately and/or independently rotatable relative to a mechanically-driven ducted fan of a turbofan of the disclosed hybrid propulsors. In some examples, the electrically-driven augmentor fan may advantageously remain operable in instances in which the mechanically-driven ducted fan stalls and/or fails. In some examples, some fan thrust associated with the electrically-driven augmentor fan may remain available following failure of a turbofan engine. The remaining available fan thrust may provide substantial benefits for an aircraft, and particularly for a twin-engine aircraft. For example, the remaining available fan thrust may advantageously provide additional total available thrust and reduced engine-failure yawing moment following a failure of a turbofan engine, thereby providing synergistic benefits in aircraft thrust sizing, vertical fin and rudder sizing, aircraft weight, and aircraft fuel efficiency. In some examples, the electrically-driven augmentor fan may be rotated at a different time and/or in a different direction relative to the time and/or direction at which the mechanically-driven ducted fan is rotated. In some such examples, the electrically-driven augmentor fan may function and/or operate as a thrust reverser having an associated direction of thrust that is opposite a direction of thrust provided by the mechanically-driven ducted fan in normal forward flight operations.

FIG. 1illustrates a first example aircraft100in which an example hybrid propulsor102having an example electrically-driven augmentor fan104may be implemented in accordance with the teachings of this disclosure. The augmentor fan104ofFIG. 1is integrated into an example nacelle106ofFIG. 1such that example augmentor fan blades108of the augmentor fan104project outwardly from the nacelle106. The nacelle106circumscribes an example ducted fan110of an example turbofan112ofFIG. 1. In the illustrated example ofFIG. 1, the turbofan112is coupled to an example wing114of the aircraft100, and the wing114is coupled to an example fuselage116of the aircraft100at a lower portion thereof. The augmentor fan104is positioned forward of the wing114of the aircraft100. The augmentor fan104ofFIG. 1and the ducted fan110ofFIG. 1are separately and/or independently rotatable. In some examples, the augmentor fan104is electrically driven (e.g., via an electrical drive incorporated into the nacelle106ofFIG. 1) and the ducted fan110is mechanically driven (e.g., via the turbofan112ofFIG. 1), thereby providing for an aircraft propulsor that is hybrid in nature.

FIG. 2is a plan view of a second example aircraft200in which an example hybrid propulsor202having an example electrically-driven augmentor fan204may be implemented in accordance with the teachings of this disclosure.FIG. 3is a side view of the second example aircraft200ofFIG. 2.FIG. 4is a front view of the second example aircraft200ofFIGS. 2 and 3. The augmentor fan204ofFIGS. 2-4is integrated into an example nacelle206ofFIGS. 2-4such that example augmentor fan blades208of the augmentor fan204project outwardly from the nacelle206. The nacelle206circumscribes an example ducted fan410of an example turbofan212ofFIGS. 2-4. In the illustrated example ofFIGS. 2-4, the turbofan212is coupled to an example wing214of the aircraft200, and the wing214is coupled to an example fuselage216of the aircraft200at a middle portion thereof. The augmentor fan204is positioned forward of the wing214of the aircraft200. The augmentor fan204ofFIGS. 2-4and the ducted fan410ofFIGS. 2-4are separately and/or independently rotatable. In some examples, the augmentor fan204is electrically driven (e.g., via an electrical drive incorporated into the nacelle206ofFIGS. 2-4) and the ducted fan410is mechanically driven (e.g., via the turbofan212ofFIGS. 2-4), thereby providing for an aircraft propulsor that is hybrid in nature.

FIG. 5is a plan view of a third example aircraft500in which an example hybrid propulsor502having an example electrically-driven augmentor fan504may be implemented in accordance with the teachings of this disclosure.FIG. 6is a side view of the third example aircraft500ofFIG. 5.FIG. 7is a front view of the third example aircraft500ofFIGS. 5 and 6. The augmentor fan504ofFIGS. 5-7is integrated into an example nacelle506ofFIGS. 5-7such that example augmentor fan blades508of the augmentor fan504project outwardly from the nacelle506. The nacelle506circumscribes an example ducted fan710of an example turbofan512ofFIGS. 5-7. In the illustrated example ofFIGS. 5-7, the turbofan512is coupled to an example fuselage516of the aircraft at an area located aft and/or rearward of an example wing514of the aircraft500. The augmentor fan504is also positioned aft and/or rearward of the wing514of the aircraft500. The augmentor fan504ofFIGS. 5-7and the ducted fan710ofFIGS. 5-7are separately and/or independently rotatable. In some examples, the augmentor fan504is electrically driven (e.g., via an electrical drive incorporated into the nacelle506ofFIGS. 5-7) and the ducted fan710is mechanically driven (e.g., via the turbofan512ofFIGS. 5-7), thereby providing for an aircraft propulsor that is hybrid in nature.

FIG. 8illustrates a fourth example aircraft800in which an example hybrid propulsor802having an example electrically-driven augmentor fan804may be implemented in accordance with the teachings of this disclosure. The augmentor fan804ofFIG. 8is integrated into an example nacelle806ofFIG. 8such that example augmentor fan blades808of the augmentor fan804project outwardly from the nacelle806. The nacelle806circumscribes an example ducted fan810of an example turbofan812ofFIG. 8. In the illustrated example ofFIG. 8, the turbofan812is coupled to an example wing814of the aircraft800, and the wing814is coupled to an example fuselage816of the aircraft100at an upper portion thereof. The augmentor fan804is positioned forward of the wing814of the aircraft800. The augmentor fan804ofFIG. 8and the ducted fan810ofFIG. 8are separately and/or independently rotatable. In some examples, the augmentor fan804is electrically driven (e.g., via an electrical drive incorporated into the nacelle806ofFIG. 8) and the ducted fan810is mechanically driven (e.g., via the turbofan812ofFIG. 8), thereby providing for an aircraft propulsor that is hybrid in nature.

The illustrated examples ofFIGS. 1-8provide several example aircraft configurations for implementing hybrid propulsors having electrically-driven augmentor fans. Additional example aircraft configurations including propulsors having mechanically-driven and/or air-driven augmentor fans that may be modified according to the teachings of this disclosure to include hybrid propulsors having electrically-driven augmentor fans are provided in U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257, as referenced above. Additional details of example hybrid propulsors having example electrically-driven augmentor fans that may be implemented in connection with such example aircraft configurations are provided herein in connection withFIGS. 9-27.

In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be coupled to a wing of an aircraft. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be coupled to a fuselage of an aircraft. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be coupled to a tail of an aircraft. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be coupled to an aircraft such that the augmentor fan is positioned forward of a wing of the aircraft. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be coupled to an aircraft such that the augmentor fan is positioned rearward of a wing of the aircraft.

In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be integrated within a nacelle of an aircraft such that the augmentor fan is positioned between a leading edge and a trailing edge of the nacelle. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be integrated within a nacelle of an aircraft such that the augmentor fan is positioned at and/or proximate a leading edge of the nacelle. In some examples, a hybrid propulsor having an electrically-driven augmentor fan as disclosed herein may be integrated within a nacelle of an aircraft such that the augmentor fan is positioned at and/or proximate a trailing edge of the nacelle.

FIG. 9is a side cross-sectional view of a first example hybrid propulsor902having an example electrically-driven augmentor fan constructed in accordance with the teachings of this disclosure.FIG. 10is a plan cross-sectional view of the first example hybrid propulsor902ofFIG. 9.FIG. 11is a front cross-sectional view of the first example hybrid propulsor902ofFIGS. 9 and 10.FIG. 12is an enlarged view of a portion ofFIG. 9.

The hybrid propulsor902ofFIGS. 9-12includes an example turbofan904having an example core engine906and an example ducted fan908to be rotated via the core engine906. In some examples, the ducted fan908is rotated in response to a combustion process occurring within the core engine906. For example, the ducted fan908ofFIGS. 9-12may be driven (e.g., mechanically driven) to rotate via an example engine shaft910of the core engine906ofFIGS. 9-12that rotates in response to a combustion process occurring within an example combustion chamber912of the core engine906, typically using a turbine driven by effluent from the combustion process. As is known from the prior art of gas turbine engines, the combustion chamber912is typically located downstream of at least one compressor (not shown) and upstream of at least one turbine (not shown).

The ducted fan908ofFIGS. 9-12includes example ducted fan blades914arranged circumferentially around the core engine906ofFIGS. 9-12. In the illustrated example ofFIGS. 9-12, the ducted fan blades914project outwardly from an example spinner916coupled to the core engine906. The ducted fan blades914and/or, more generally, the ducted fan908, is/are circumscribed by an example fan cowl918, and the fan cowl918is circumscribed by an example nacelle920. Thus, the ducted fan blades914and/or, more generally, the ducted fan908is/are circumscribed by the nacelle920ofFIGS. 9-12. The nacelle920includes an example inner surface922, an example outer surface924located opposite the inner surface922, an example leading edge926, and an example trailing edge928located opposite the leading edge926.

In the illustrated example ofFIGS. 9-12, the core engine906of the turbofan904is coupled to the nacelle920via example duct support struts930. The core engine906of the turbofan904is also coupled to an example wing932of an aircraft via an example propulsor support934. As shown inFIGS. 10 and 11, the wing932ofFIGS. 9-12is coupled to an example fuselage1002of the aircraft.

The hybrid propulsor902ofFIGS. 9-12also includes an example an augmentor fan936having an example augmentor hub ring938and example augmentor fan blades940. The augmentor fan blades940are arranged circumferentially around the augmentor hub ring938and project outwardly relative to the outer surface924of the nacelle920ofFIGS. 9-12. In the illustrated example ofFIGS. 9-12, the augmentor hub ring938circumscribes the inner surface922of the nacelle920and is located proximate the outer surface924of the nacelle920. In some examples, an outer surface of the augmentor hub ring938ofFIGS. 9-12is aligned with (e.g., is flush with) the outer surface924of the nacelle920ofFIGS. 9-12. As shown inFIG. 12, the augmentor hub ring938ofFIGS. 9-12is rotatably coupled to the nacelle920ofFIGS. 9-12via example stewing ring bearings1202located within the nacelle920proximate the outer surface924of the nacelle920.

In the illustrated example ofFIGS. 9-12, the augmentor hub ring938of the augmentor fan936is electrically driven by one or more example electrical drive(s)942located within the nacelle920. In some examples, a plurality of electrical drives942may be located within the nacelle920(e.g., between the inner surface922and the outer surface924of the nacelle920) and arranged circumferentially around the inner surface922of the nacelle920. As described in greater detail below in connection withFIGS. 14-26, respective ones of the electrical drive(s)942ofFIGS. 9-12may include one or more electric motor(s) such as, for example, a brushless ring motor or an axial flux synchronous permanent magnet motor.

In the illustrated example ofFIGS. 9-12, the electrical drive(s)942ofFIGS. 9-12rotate the augmentor hub ring938of the augmentor fan936in response to a supply of electrical energy provided to the electrical drive(s)942from one or more electrical energy source(s) (not shown inFIGS. 9-12) located within and/or coupled to the aircraft. As described in greater detail below in connection withFIG. 13, the electrical energy to be provided to the electrical drive(s)942ofFIGS. 9-12may be generated and/or supplied via an electrical generator of an auxiliary power unit of the aircraft, or via an electrical generator of a gas turbine of the aircraft. The electrical energy may additionally or alternatively be supplied via one or more electrical energy storage device(s) of the aircraft such as, for example, one or more batter(ies), flywheel(s), or supercapacitor(s). Energy to be supplied to the electrical drive(s)942ofFIGS. 9-12via one or more of the aforementioned electrical energy source(s) may be supplied via one or more wire(s) and/or electrical conduit(s) operatively coupling the electrical energy source(s) to the electrical drive(s)942. In some examples, such wire(s) and/or electrical conduit(s) may be routed from the electrical energy source(s) to the electrical drive(s)942ofFIGS. 9-12through one or more of the nacelle920, the duct support struts930, the core engine906, the propulsor support934, the wing932, and/or the fuselage1002ofFIGS. 9-12.

As shown inFIG. 12, the hybrid propulsor902ofFIGS. 9-12includes an example pitch control mechanism1204to control the pitch angle (e.g., the blade angle) of respective ones of the augmentor fan blades940coupled to the augmentor hub ring938. Example mechanically-driven pitch control mechanism(s) that may be utilized to implement the pitch control mechanism1204ofFIG. 12are provided in U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257, as referenced above. Electrically-driven pitch control mechanism(s) including one or more electrical drive(s) and/or electric motor(s) may also be utilized to implement the pitch control mechanism1204ofFIG. 12.

In some examples, the pitch control mechanism1204ofFIG. 12may adjust the positions of respective ones of the augmentor fan blades940ofFIGS. 9-12from a fine position to a feather position (and vice-versa), and/or to any position therebetween. In some examples, the pitch control mechanism1204ofFIG. 12may vary the positions of respective ones of the augmentor fan blades940ofFIGS. 9-12during flight and/or ground operations to provide desirable blade angles of attack that are optimized with respect to a measure of one or more of aerodynamic efficiency, fuel efficiency, community noise, cabin noise, emissions, takeoff performance, climb performance, cruise performance, descent performance, and/or reverse thrust performance associated with the hybrid propulsor902ofFIGS. 9-12and/or the aircraft to which the hybrid propulsor is coupled. The pitch control mechanism1204ofFIG. 12may also vary the positions of respective ones of the augmentor fan blades940ofFIGS. 9-12during flight to provide desirable blade angles of attack that are optimized with respect to a division of power between the ducted fan908and the augmentor fan936ofFIGS. 9-12.

In some examples, the pitch control mechanism1204ofFIG. 13may adjust the positions of respective ones of the augmentor fan blades940ofFIGS. 9-12such that rotation of the augmentor fan blades940via the augmentor hub ring938ofFIGS. 9-12generates a thrust in a direction that is opposite relative to a direction of a thrust generated via rotation of the ducted fan blades914ofFIGS. 9-12during normal forward flight. The pitch control mechanism1204ofFIG. 12may accordingly cause the augmentor fan blades940and/or, more generally, the augmentor fan936ofFIGS. 9-12to function and/or operate as a thrust reverser, with reverse thrust blade orientations achieved either through fine pitch or through feather pitch. In some examples, implementing the pitch control mechanism1204ofFIG. 12as a thrust reverser may allow for the omission and/or elimination of a conventional thrust reverser (e.g., blocker doors, cascade reversers, translating cascades, clamshell reverser members, multi-door reverser members, etc.) from the nacelle920. Augmentor blade pitch angle values may also be set to an orientation to enable regenerative braking during aircraft descent, by slowing aircraft speed and reversing power flow from the motors so they can serve as generators.

In the illustrated example ofFIGS. 9-12, the augmentor hub ring938, the augmentor fan blades940and/or, more generally, the augmentor fan936is/are positioned forward of the wing932of the aircraft. In other example, the augmentor hub ring938, augmentor fan blades940and/or, more generally, the augmentor fan936ofFIGS. 9-12may alternatively be positioned rearward of the wing932of the aircraft. In the illustrated example ofFIGS. 9-12, the augmentor hub ring938is positioned approximately midway between the leading edge926and the trailing edge928of the nacelle920ofFIGS. 9-12. In other examples, the augmentor hub ring938ofFIGS. 9-12may alternatively be positioned at and/or proximate the leading edge926of the nacelle920. In still other examples, the augmentor hub ring938ofFIGS. 9-12may alternatively be positioned at and/or proximate the trailing edge928of the nacelle920.

In the illustrated example ofFIGS. 9-12, the augmentor fan936and the ducted fan908are separately and/or independently rotatable. In some examples, the augmentor fan936is electrically driven via the electrical drive(s)942ofFIGS. 9-12, and the ducted fan908is mechanically driven via the engine shaft910and/or the core engine906ofFIGS. 9-12, thereby providing for an aircraft propulsor that is hybrid in nature (e.g., the hybrid propulsor902ofFIGS. 9-12). In some examples, the augmentor fan936ofFIGS. 9-12may rotate in a first direction (e.g., clockwise), and the ducted fan908ofFIGS. 9-12may rotate in a second direction (e.g., clockwise) that is the same as the first direction. In other examples, the augmentor fan936ofFIGS. 9-12may rotate in a first direction (e.g., clockwise), and the ducted fan908ofFIGS. 9-12may rotate in a second direction (e.g., counterclockwise) that is opposite the first direction.

FIG. 13is a block diagram of an example electrical drive control apparatus1300constructed in accordance with the teachings of this disclosure. The electrical drive control apparatus1300ofFIG. 13may be integrated and/or otherwise incorporated into an aircraft to operate a hybrid aircraft propulsor of the aircraft having an electrically-driven augmentor fan (e.g., the hybrid propulsor902ofFIGS. 9-12, the hybrid propulsor1602ofFIGS. 16 and 17, the hybrid propulsor1802ofFIGS. 18 and 19, the hybrid propulsor2302ofFIGS. 23 and 24, the hybrid propulsor2502ofFIGS. 25 and 26, etc.). In the illustrated example ofFIG. 13, the electrical drive control apparatus1300includes an example electrical drive1302, an example controller1304, an example auxiliary power unit (APU)1306having an example electrical generator1308, an example gas turbine1310having an example electrical generator1312, an example battery1314, an example flywheel1316, and an example supercapacitor1318. In other examples, the electrical drive control apparatus1300may lack one or more of the auxiliary power unit1306, the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13.

In the illustrated example ofFIG. 13, the connecting lines shown between various ones of the electrical drive1302, the controller1304, the auxiliary power unit1306having the electrical generator1308, the gas turbine1310having the electrical generator1312, the battery1314, the flywheel1316, and the supercapacitor1318represent operative couplings that include power connections as well as signal connections. For example, the connecting lines ofFIG. 13represent power connections that may include electrical wire for conducting electrical energy or power. The connecting lines ofFIG. 13further represent signal connections that may include electrical or optical wire and/or cable, or electrical or optical data buses, for transmitting and/or carrying signals such as sensor signals, command signals, control signals, etc.

In the illustrated example ofFIG. 13, the electrical drive1302is operatively coupled (e.g., via one or more wire(s) and/or electrical conduit(s)) to respective ones of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318. The electrical drive1302ofFIG. 13may be implemented via one or more of the example electrical drive(s)942ofFIGS. 9-12described above. The electrical drive1302ofFIG. 13rotates an augmentor hub ring of an augmentor fan (e.g., the augmentor hub ring938of the augmentor fan936ofFIGS. 9-12) in response to a supply of electrical energy provided to the electrical drive1302from one or more electrical energy source(s). In the illustrated example ofFIG. 13, the electrical energy source(s) include any and/or all of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318. The electrical generator1308of the auxiliary power unit1306ofFIG. 13and the electrical generator1312of the gas turbine1310ofFIG. 13are example electrical energy generating devices capable of generating electrical energy to be supplied to the electrical drive1302ofFIG. 13. The battery1314, the flywheel1316, and the supercapacitor1318ofFIG. 13are example electrical energy storage devices capable of storing electrical energy to be supplied to the electrical drive1302ofFIG. 13. The electrical drive control apparatus1300ofFIG. 13may additionally or alternatively include other types of electrical energy generating devices and/or other types of electrical energy storage devices commonly found in aircraft.

In the illustrated example ofFIG. 13, the controller1304is operatively coupled to the electrical drive1302, and is also operatively coupled to the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318. The controller1304ofFIG. 13controls, manages and/or regulates the supply of electrical energy to and/or the conversion of electrical energy by the electrical drive1302ofFIG. 13. For example, the controller1304may control a flow of electrical energy to be supplied to the electrical drive1302as provided by one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13. In the illustrated example ofFIG. 13, the electrical drive1302rotates an augmentor hub ring of an augmentor fan (e.g., the augmentor hub ring938of the augmentor fan936ofFIGS. 9-12) at specific speeds (e.g., specific angular velocities) and/or specific times based on the extent and/or degree of the controlled electrical energy supplied to the electrical drive1302via the controller1304, and/or based on the timing at which the controller1304provides such controlled electrical energy to the electrical drive1302. In some examples, the controller1304ofFIG. 13may additionally be operatively coupled to one or more sensor(s) and/or interface(s) including, for example, a pilot interface (e.g., one or more input device(s) and/or output device(s)), a thrust management system interface, and/or a flight management system interface. In such examples, the controller1304ofFIG. 13may receive input(s) from and/or provide output(s) to the sensor(s) and/or the interface(s) to facilitate and/or provide an indication of one or more operation(s) associated with the controller1304, including for example the control, management and/or regulation of the supply of electrical energy to, and/or the conversion of electrical energy by, the electrical drive1302ofFIG. 13.

FIG. 14is a side cross-sectional view of a first known brushless ring motor1400. The brushless ring motor1400ofFIG. 14includes a stator1402and a rotor1404. The stator1402ofFIG. 14is stationary. The rotor1404ofFIG. 14rotates relative to the stator1402. The rotor1404includes an inner wall1406and an outer wall1408. As shown inFIG. 14, one or more inner magnet(s)1410are coupled to an outer surface of the inner wall1406of the rotor1404, and one or more outer magnet(s)1412are coupled to an inner surface of the outer wall1408of the rotor1404such that the outer magnet(s)1412face the inner magnet(s)1410. The stator1402ofFIG. 14is positioned between the inner magnet(s)1410of the inner wall1406of the rotor1404and the outer magnet(s)1412of the outer wall1408of the rotor1404ofFIG. 14. An electric field generated via the stator1402ofFIG. 14is applied to the inner magnet(s)1410and the outer magnet(s)1412. The inner wall1406and the outer wall1408of the rotor1404ofFIG. 14rotate together in response to the application of the electric field. Rotation of the rotor1404ofFIG. 14causes an output shaft1414coupled to the rotor1404to rotate. One or more of the electrical drive(s)942ofFIGS. 9-12described above may be implemented via the brushless ring motor1400ofFIG. 14or a modified form and/or version thereof.

FIG. 15is a front cross-sectional view of a second known brushless ring motor1500. The brushless ring motor1500ofFIG. 15includes a stator1502and a rotor1504. The stator1502ofFIG. 15is stationary. The rotor1504ofFIG. 15rotates relative to the stator1502. The rotor1504includes an inner wall1506and an outer wall1508. As shown inFIG. 15, one or more inner magnet(s)1510are coupled to an outer surface of the inner wall1506of the rotor1504. One or more outer magnet(s) (not shown inFIG. 15) may additionally be coupled to an inner surface of the outer wall1508of the rotor1504such that the outer magnet(s) face the inner magnet(s)1510. The stator1502ofFIG. 15is positioned between the inner wall1506of the rotor1504and the outer wall1508of the rotor1504ofFIG. 15. An electric field generated via the stator1502ofFIG. 15is applied to the inner magnet(s)1510, and to the outer magnet(s) if present. The inner wall1506and the outer wall1508of the rotor1504ofFIG. 15rotate together in response to the application of the electric field. One or more of the electrical drive(s)942ofFIGS. 9-12described above may be implemented via the brushless ring motor1500ofFIG. 15or a modified form and/or version thereof.

FIG. 16is a side cross-sectional view of a second example hybrid propulsor1602including a first example brushless ring motor1604.FIG. 17is an enlarged view of a portion ofFIG. 16. The second example hybrid propulsor1602ofFIGS. 16 and 17includes the turbofan904, the core engine906, the ducted fan908, the engine shaft910, the combustion chamber912, the ducted fan blades914, the spinner916, the fan cowl918, the nacelle920, the inner surface922, the outer surface924, the leading edge926, the trailing edge928, the duct support struts930, the augmentor fan936, the augmentor hub ring938, the augmentor fan blades940, the stewing ring bearings1202, and the pitch control mechanism1204described above in connection with the first example hybrid propulsor ofFIGS. 9-12. In the interest of conciseness, the respective descriptions of such items provided above are not repeated here in reference to the second example hybrid propulsor1602ofFIGS. 16 and 17.

The example brushless ring motor1604ofFIGS. 16 and 17is an electric motor that may be implemented and/or function as an electrical drive to rotate the augmentor hub ring938of the augmentor fan936ofFIGS. 16 and 17. The brushless ring motor1604ofFIGS. 16 and 17is located within and/or integrated into the nacelle920ofFIGS. 16 and 17. The brushless ring motor1604rotates the augmentor hub ring938in response to a supply of electrical energy provided to the brushless ring motor1604from one or more electrical energy source(s) (not shown inFIGS. 16 and 17) located within and/or coupled to the aircraft. For example, the brushless ring motor1604ofFIGS. 16 and 17may rotate the augmentor hub ring938in response to a supply of electrical energy provided to the brushless ring motor1604from one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13described above.

In the illustrated example ofFIGS. 16 and 17, the brushless ring motor1604includes an example stator1702and an example rotor1704. The stator1702ofFIG. 17is stationary. The rotor1704ofFIG. 17rotates relative to the stator1702. The rotor1704includes an inner wall1706and an outer wall1708. As shown inFIG. 17, one or more inner magnet(s)1710are coupled to an outer surface of the inner wall1706of the rotor1704, and one or more outer magnet(s)1712are coupled to an inner surface of the outer wall1708of the rotor1704such that the outer magnet(s)1712face the inner magnet(s)1710. The stator1702ofFIG. 17is positioned between the inner magnet(s)1710of the inner wall1706of the rotor1704and the outer magnet(s)1712of the outer wall1708of the rotor1704ofFIG. 17. An electric field generated via the stator1702ofFIG. 17is applied to the inner magnet(s)1710and the outer magnet(s)1712. The inner wall1706and the outer wall1708of the rotor1704ofFIG. 17rotate together in response to the application of the electric field. The augmentor hub ring938of the augmentor fan936ofFIGS. 16 and 17is coupled to the rotor1704of the brushless ring motor1604ofFIGS. 16 and 17such that the augmentor hub ring938rotates along with the rotor1704(e.g., such that rotation of the rotor1704causes rotation of the augmentor hub ring938).

FIG. 18is a side cross-sectional view of a third example hybrid propulsor1802including a second example brushless ring motor1804.FIG. 19is an enlarged view of a portion ofFIG. 18. The third example hybrid propulsor1802ofFIGS. 18 and 19includes the turbofan904, the core engine906, the ducted fan908, the engine shaft910, the combustion chamber912, the ducted fan blades914, the spinner916, the fan cowl918, the nacelle920, the inner surface922, the outer surface924, the leading edge926, the trailing edge928, the duct support struts930, the augmentor fan936, the augmentor hub ring938, the augmentor fan blades940, the stewing ring bearings1202, and the pitch control mechanism1204described above in connection with the first example hybrid propulsor ofFIGS. 9-12. In the interest of conciseness, the respective descriptions of such items provided above are not repeated here in reference to the third example hybrid propulsor1802ofFIGS. 18 and 19.

The example brushless ring motor1804ofFIGS. 18 and 19is an electric motor that may be implemented and/or function as an electrical drive to rotate the augmentor hub ring938of the augmentor fan936ofFIGS. 18 and 19. The brushless ring motor1804ofFIGS. 18 and 19is located within and/or integrated into the nacelle920ofFIGS. 18 and 19. The brushless ring motor1804rotates the augmentor hub ring938in response to a supply of electrical energy provided to the brushless ring motor1804from one or more electrical energy source(s) (not shown inFIGS. 18 and 19) located within and/or coupled to the aircraft. For example, the brushless ring motor1804ofFIGS. 18 and 19may rotate the augmentor hub ring938in response to a supply of electrical energy provided to the brushless ring motor1804from one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13described above.

In the illustrated example ofFIGS. 18 and 19, the brushless ring motor1804includes an example stator1902and an example rotor1904. The stator1902ofFIG. 19is stationary. The rotor1904ofFIG. 19rotates relative to the stator1902. The stator1902includes an inner wall1906and an outer wall1908. As shown inFIG. 19, one or more inner magnet(s)1910are coupled to an outer surface of the inner wall1906of the stator1902, and one or more outer magnet(s)1912are coupled to an inner surface of the outer wall1908of the stator1902such that the outer magnet(s)1912face the inner magnet(s)1910. The rotor1904ofFIG. 19is positioned between the inner magnet(s)1910of the inner wall1906of the stator1902and the outer magnet(s)1912of the outer wall1908of the stator1902ofFIG. 19. An electric field generated via the rotor1904ofFIG. 19is applied to the inner magnet(s)1910and the outer magnet(s)1912. The rotor1904ofFIG. 19rotates in response to the application of the electric field. The augmentor hub ring938of the augmentor fan936ofFIGS. 18 and 19is coupled to the rotor1904of the brushless ring motor1804ofFIGS. 18 and 19such that the augmentor hub ring938rotates along with the rotor1904(e.g., such that rotation of the rotor1904causes rotation of the augmentor hub ring938).

FIG. 20is a front view of a known axial flux synchronous permanent magnet motor2000.FIG. 21is a side cross-sectional view of the known axial flux synchronous permanent magnet motor2000ofFIG. 20.FIG. 22is a rear view of the known axial flux synchronous permanent magnet motor2000ofFIGS. 20 and 21. The axial flux synchronous permanent magnet motor2000ofFIGS. 20-22includes a stator2102and a rotor2104. The stator2102ofFIG. 21is stationary. The rotor2104ofFIG. 21rotates relative to the stator2102in response to an electric filed applied to one or more permanent magnet(s) of the axial flux synchronous permanent magnet motor2000ofFIGS. 20-22via the stator2102ofFIG. 21. The rotor2104ofFIG. 21includes and/or is coupled to an output socket2106that rotates along with the rotor2104. Rotational motion of the rotor2104and/or the output socket2106ofFIG. 21may be transferred to another structure and/or device via a transmission shaft (not shown inFIGS. 20-22) coupled to the output socket2106of the axial flux synchronous permanent magnet motor2000ofFIGS. 20-22. One or more of the electrical drive(s)942ofFIGS. 9-12described above may be implemented via the axial flux synchronous permanent magnet motor2000ofFIGS. 20-22or a modified form and/or version thereof.

FIG. 23is a side cross-sectional view of a fourth example hybrid propulsor2302including a first example axial flux synchronous permanent magnet motor2304.FIG. 24is an enlarged view of a portion ofFIG. 23. The fourth example hybrid propulsor2302ofFIGS. 23 and 24includes the turbofan904, the core engine906, the ducted fan908, the engine shaft910, the combustion chamber912, the ducted fan blades914, the spinner916, the fan cowl918, the nacelle920, the inner surface922, the outer surface924, the leading edge926, the trailing edge928, the duct support struts930, the augmentor fan936, the augmentor hub ring938, the augmentor fan blades940, the stewing ring bearings1202, and the pitch control mechanism1204described above in connection with the first example hybrid propulsor ofFIGS. 9-12. In the interest of conciseness, the respective descriptions of such items provided above are not repeated here in reference to the fourth example hybrid propulsor2302ofFIGS. 23 and 24.

The example axial flux synchronous permanent magnet motor2304ofFIGS. 23 and 24is an electric motor that may be implemented and/or function as an electrical drive to rotate the augmentor hub ring938of the augmentor fan936ofFIGS. 23 and 24. The axial flux synchronous permanent magnet motor2304ofFIGS. 23 and 24is located within and/or integrated into the nacelle920ofFIGS. 23 and 24. The axial flux synchronous permanent magnet motor2304rotates the augmentor hub ring938in response to a supply of electrical energy provided to the axial flux synchronous permanent magnet motor2304from one or more electrical energy source(s) (not shown inFIGS. 23 and 24) located within and/or coupled to the aircraft. For example, the axial flux synchronous permanent magnet motor2304ofFIGS. 23 and 24may rotate the augmentor hub ring938in response to a supply of electrical energy provided to the axial flux synchronous permanent magnet motor2304from one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13described above.

In the illustrated example ofFIGS. 23 and 24, the axial flux synchronous permanent magnet motor2304is operatively coupled to the augmentor hub ring938of the augmentor fan936ofFIGS. 22 and 23via an example output shaft2306, an example powered drive gear2308, and an example augmentor hub ring drive gear2310. The output shaft2306ofFIGS. 23 and 24is coupled to a rotor of the axial flux synchronous permanent magnet motor2304such that rotational motion of the rotor is transferred to the output shaft2306. The powered drive gear2308ofFIGS. 23 and 24is coupled to the output shaft2306ofFIGS. 23 and 24such that rotational motion of the output shaft2306is transferred to the powered drive gear2308. The augmentor hub ring drive gear2310ofFIGS. 23 and 24is rigidly coupled to the augmentor hub ring938of the augmentor fan936ofFIGS. 23 and 24. The augmentor hub ring drive gear2310ofFIGS. 23 and 24engages the powered drive gear2308ofFIGS. 23and24such that rotational motion of the powered drive gear2308is transferred to the augmentor hub ring938of the augmentor fan936ofFIGS. 23 and 24via the augmentor hub ring drive gear2310.

FIG. 25is a side cross-sectional view of a fifth example hybrid propulsor2502including a second example axial flux synchronous permanent magnet motor2504.FIG. 26is an enlarged view of a portion ofFIG. 25. The fifth example hybrid propulsor2502ofFIGS. 25 and 26includes the turbofan904, the core engine906, the ducted fan908, the engine shaft910, the combustion chamber912, the ducted fan blades914, the spinner916, the fan cowl918, the nacelle920, the inner surface922, the outer surface924, the leading edge926, the trailing edge928, the duct support struts930, the augmentor fan936, the augmentor hub ring938, the augmentor fan blades940, the electrical drive(s)942, the stewing ring bearings1202, and the pitch control mechanism1204described above in connection with the first example hybrid propulsor ofFIGS. 9-12. In the interest of conciseness, the respective descriptions of such items provided above are not repeated here in reference to the fifth example hybrid propulsor2502ofFIGS. 25 and 26. Unlike the example ofFIGS. 9-12in which the augmentor fan936(e.g., including the augmentor hub ring938and the augmentor fan blades940) is positioned approximately midway between the leading edge926and the trailing edge928of the nacelle920ofFIGS. 9-12, the augmentor fan936(e.g., including the augmentor hub ring938and the augmentor fan blades940) ofFIGS. 25 and 26is positioned proximate and/or implemented as the leading edge926of the nacelle920ofFIGS. 25 and 26.

The example axial flux synchronous permanent magnet motor2504ofFIGS. 25 and 26is an electric motor that may be implemented and/or function as an electrical drive to rotate the augmentor hub ring938of the augmentor fan936ofFIGS. 25 and 26. The axial flux synchronous permanent magnet motor2504ofFIGS. 24 and 25is located within and/or integrated into the nacelle920ofFIGS. 25 and 26. The axial flux synchronous permanent magnet motor2504rotates the augmentor hub ring938in response to a supply of electrical energy provided to the axial flux synchronous permanent magnet motor2504from one or more electrical energy source(s) (not shown inFIGS. 25 and 26) located within and/or coupled to the aircraft. For example, the axial flux synchronous permanent magnet motor2504ofFIGS. 25 and 26may rotate the augmentor hub ring938in response to a supply of electrical energy provided to the axial flux synchronous permanent magnet motor2504from one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13described above.

In the illustrated example ofFIGS. 25 and 26, the axial flux synchronous permanent magnet motor2504is operatively coupled to the augmentor hub ring938of the augmentor fan936ofFIGS. 25 and 26via an example output shaft2506, an example powered drive gear2508, and an example augmentor hub ring drive gear2510. The output shaft2506ofFIGS. 25 and 26is coupled to a rotor of the axial flux synchronous permanent magnet motor2504such that rotational motion of the rotor is transferred to the output shaft2506. The powered drive gear2508ofFIGS. 25 and 26is coupled to the output shaft2506ofFIGS. 25 and 26such that rotational motion of the output shaft2506is transferred to the powered drive gear2508. The augmentor hub ring drive gear2510ofFIGS. 25 and 26is rigidly coupled to the augmentor hub ring938of the augmentor fan936ofFIGS. 25 and 26. The augmentor hub ring drive gear2510ofFIGS. 25 and 26engages the powered drive gear2508ofFIGS. 25 and 26such that rotational motion of the powered drive gear2508is transferred to the augmentor hub ring938of the augmentor fan936ofFIGS. 25 and 26via the augmentor hub ring drive gear2510.

FIG. 27is a flowchart representative of an example method2700for operating a hybrid aircraft propulsor having an electrically-driven augmentor fan (e.g., the hybrid propulsor902ofFIGS. 9-12having the electrically-driven augmentor fan936ofFIGS. 9-12). The method2700ofFIG. 27may be implemented in part by an electrical drive control apparatus such as the example electrical drive control apparatus1300ofFIG. 13. The example method2700ofFIG. 27includes rotating a ducted fan of a turbofan via a core engine of the turbofan (block2702). For example, the ducted fan908of the turbofan904ofFIGS. 9-12may be mechanically driven to rotate via the core engine906of the turbofan904ofFIGS. 9-12in response to a combustion process occurring in the core engine906.

The example method2700ofFIG. 27also includes rotating an augmentor fan via an electrical drive in response to a supply of electrical energy provided to the electrical drive (block2704). For example, the augmentor fan936ofFIGS. 9-12may be electrically driven to rotate via the electrical drive(s)942ofFIGS. 9-12in response to a supply of electrical energy provided to the electrical drive(s)942from one or more electrical energy source(s). Such energy source(s) may include, for example, one or more of the electrical generator1308of the auxiliary power unit1306, the electrical generator1312of the gas turbine1310, the battery1314, the flywheel1316, and/or the supercapacitor1318ofFIG. 13. In some examples, the flow and/or supply of electrical energy to be provided to the electrical drive may be controlled, managed and/or regulated via a controller. For example, the controller1304of the electrical drive control apparatus1300ofFIG. 13may control, manage and/or regulate the flow and/or supply of electrical energy from the above-described electrical energy source(s) ofFIG. 13to the electrical drive1302ofFIG. 13, which may be implemented via the electrical drive(s)942ofFIGS. 9-12. In some examples, the rotating of the augmentor fan (block2704) is separate from the rotating of the ducted fan (block2702) such that the augmentor fan rotates separately and/or independently from the ducted fan. For example, the rotating of the electrically-driven augmentor fan936ofFIGS. 9-12is separate from the rotating of the mechanically-driven ducted fan908ofFIGS. 9-12such that the augmentor fan936rotates separately and/or independently from the ducted fan908. Following block2704, the example method2700ofFIG. 27ends.

From the foregoing, it will be appreciated that hybrid aircraft propulsors having electrically-driven augmentor fans are disclosed. As a result of being powered by electrical energy as opposed being powered mechanically and/or by jet fuel, the disclosed electrically-driven augmentor fans advantageously provide increases in fuel efficiency and reductions in operating costs relative to the mechanically-drive and/or air-driven augmentor fans described in U.S. Pat. No. 8,689,538 and U.S. Patent Publication No. 2017/0122257, as referenced above. The disclosed hybrid propulsors and/or electrically-driven augmentor fans also advantageously provide environmental benefits such as reduced carbon emissions.

The disclosed hybrid propulsors and/or electrically-driven augmentor fans advantageously leverage electrical energy produced and/or stored by conventional electrical energy sources of an aircraft. For example, the disclosed electrically-driven augmentor fans may receive a supply of electrical energy generated by an electrical generator of an auxiliary power unit and/or by an electrical generator of a gas turbine of an aircraft implementing the disclosed hybrid propulsors. The disclosed electrically-driven augmentor fans may additionally or alternatively receive a supply of electrical energy from one or more electrical energy storage device(s) of the aircraft, including, for example, a battery, a flywheel, and/or a supercapacitor.

As a result of being powered by an electrical energy source as opposed to being powered mechanically and/or by jet fuel, an electrically-driven augmentor fan of the disclosed hybrid propulsors is separately and/or independently rotatable relative to a mechanically-driven ducted fan of a turbofan of the disclosed hybrid propulsors. In some examples, the electrically-driven augmentor fan may advantageously remain operable in instances in which the mechanically-driven ducted fan stalls and/or fails. In some examples, some fan thrust associated with the electrically-driven augmentor fan may remain available following failure of a turbofan engine. The remaining available fan thrust may provide substantial benefits for an aircraft, and particularly for a twin-engine aircraft. For example, the remaining available fan thrust may advantageously provide additional total available thrust and reduced engine-failure yawing moment following a failure of a turbofan engine, thereby providing synergistic benefits in aircraft thrust sizing, vertical fin and rudder sizing, aircraft weight, and aircraft fuel efficiency. In some examples, the electrically-driven augmentor fan may be rotated at a different time and/or in a different direction relative to the time and/or direction at which the mechanically-driven ducted fan is rotated. In some such examples, the electrically-driven augmentor fan may function and/or operate as a thrust reverser having an associated direction of thrust that is opposite a direction of thrust provided by the mechanically-driven ducted fan.

In some examples, an apparatus is disclosed. In some disclosed examples, the apparatus comprises a turbofan including a core engine and a ducted fan to be rotated via the core engine. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the apparatus further comprises an augmentor fan including an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the augmentor fan is to rotate separately from the ducted fan. In some disclosed examples, the apparatus further comprises an electrical drive to rotate the augmentor hub ring in response to a supply of electrical energy provided to the electrical drive.

In some disclosed examples, the electrical drive is located between the outer surface and an inner surface of the nacelle. In some disclosed examples, the electrical drive includes an electric motor. In some disclosed examples, the electric motor is one of a brushless ring motor or an axial flux synchronous permanent magnet motor. In some disclosed examples, the electrical drive includes a plurality of electric motors located between the outer surface and the inner surface of the nacelle and arranged circumferentially around the inner surface.

In some disclosed examples, the apparatus further comprises a controller to control the supply of electrical energy provided to the electrical drive. In some disclosed examples, the supply of electrical energy is generated via an electrical generator of an auxiliary power unit, the electrical generator being operatively coupled to the electrical drive. In some disclosed examples, the supply of electrical energy is generated via an electrical generator of a gas turbine, the electrical generator being operatively coupled to the electrical drive. In some disclosed examples, the supply of electrical energy is provided via an electrical energy storage device operatively coupled to the electrical drive. In some disclosed examples, the electrical energy storage device is one of a battery, a flywheel, or a supercapacitor.

In some disclosed examples, an outer surface of the augmentor hub ring is substantially aligned with the outer surface of the nacelle. In some disclosed examples, the augmentor hub ring is located aft of the ducted fan blades. In some disclosed examples, the augmentor hub ring is located forward of the ducted fan blades. In some disclosed examples, the augmentor fan further includes a pitch control mechanism to adjust a pitch angle of the augmentor fan blades.

In some examples, an apparatus is disclosed. In some disclosed examples, the apparatus comprises a turbofan including a core engine and a ducted fan to be rotated via the core engine. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the apparatus further comprises an augmentor fan including an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the augmentor fan is to rotate separately from the ducted fan. In some disclosed examples, the apparatus further comprises means for driving the augmentor hub ring to rotate in response to a supply of electrical energy provided to the means for driving.

In some disclosed examples, the apparatus further comprises means for generating the supply of electrical energy to be provided to the means for driving. In some disclosed examples, the means for generating is operatively coupled to the means for driving. In some disclosed examples, the apparatus further comprises means for storing the supply of electrical energy to be provided to the means for driving. In some disclosed examples, the means for storing is operatively coupled to the means for driving.

In some examples, a method is disclosed. In some disclosed examples, the method comprises rotating a ducted fan of a turbofan via a core engine of the turbofan. In some disclosed examples, the ducted fan includes a plurality of ducted fan blades arranged circumferentially around the core engine and circumscribed by a nacelle. In some disclosed examples, the method further comprises rotating an augmentor fan via an electrical drive in response to a supply of electrical energy provided to the electrical drive. In some disclosed examples, the augmentor fan includes an augmentor hub ring and a plurality of augmentor fan blades. In some disclosed examples, the augmentor fan blades are arranged circumferentially around the augmentor hub ring and project outwardly relative to an outer surface of the nacelle. In some disclosed examples, the rotating of the augmentor fan is separate from the rotating of the ducted fan.

In some disclosed examples, the method further comprises generating the electrical energy to be supplied to the electrical drive. In some disclosed examples, the electrical energy is to be generated via an electrical generator operatively coupled to the electrical drive, the electrical generator being included in one of an auxiliary power unit or a gas turbine. In some disclosed examples, the method further comprises storing the electrical energy to be supplied to the electrical drive. In some disclosed examples, the electrical energy is to be stored via an electrical energy storage device operatively coupled to the electrical drive. In some disclosed examples, the electrical energy storage device is one of a battery, a flywheel, or a supercapacitor.

Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent. In some examples, hybrid aircraft propulsors having electrically-driven augmentor fans as disclosed above may be combined with one or more of the alternate drive systems described in U.S. Pat. No. 8,689,538 and/or U.S. Patent Publication No. 2017/0122257 to provide variant hybrid systems incorporating plural and/or selectable power transmission mechanisms into an augmentor fan.