Patent Publication Number: US-2020277065-A1

Title: Distributed propulsion configurations for aircraft having mixed drive systems

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62/812,315, filed Mar. 1, 2019, and U.S. Provisional Patent Application No. 62/821,367, filed Mar. 20, 2019, the disclosures of each of which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The subject invention is directed to propulsion configurations in aircraft, and more particularly, to a series of distributed propulsion configurations for an aircraft having mixed drive systems, including hybrid-electric propulsion systems. 
     2. Description of Related Art 
     The level of air traffic continues to increase worldwide, leading to increased fuel consumption and air pollution. Consequently, efforts are underway to make aircraft more environmentally compatible through the use of specific types of fuel and/or by reducing fuel consumption through the use of more efficient drive systems. 
     For example, aircraft having mixed drive systems that include a combination of various types of engines are known for reducing pollutants and increasing efficiency. Some current combinations include reciprocating engines and jet engines, reciprocating engines and rocket engines, jet engines and rocket engines, or turbojet engines and ramjet engines. 
     While these mixed drive systems are useful, they are not readily adaptable for use on commercial passenger aircraft. However, hybrid-electric propulsion systems that provide power through a combustion engine and an electric motor are indeed adaptable for use with commercial passenger aircraft and can provide efficiency benefits including reduced fuel consumption. The subject invention is directed to aircraft having such propulsion systems. 
     SUMMARY OF THE DISCLOSURE 
     The subject invention is directed to an aircraft propulsion system that includes at least one hybrid-electric powerplant for delivering power to an air mover for propelling the aircraft, wherein the at least one hybrid-electric powerplant includes a heat engine and an electric motor arranged in a parallel drive configuration or in an in-line drive configuration. The power delivery from the hybrid-electric powerplant can be about evenly split between the heat engine and the electric motor, or the power delivery from the hybrid-electric powerplant can be proportionally split between the heat engine and the electric motor. 
     It is envisioned that the heat engine could be configured as a rotary engine, a reciprocating engine of any fuel type with a configuration of turbomachinery elements, selected from a group consisting of a turbocharger, turbo-supercharger, or supercharger and exhaust recovery turbo compounding, which is mechanically, electrically, hydraulically or pneumatically driven. 
     In one embodiment, at least one hybrid-electric powerplant is associated with each wing of the aircraft. By way of example, three hybrid-electric powerplants may be distributed along each wing of the aircraft, with one hybrid-electric powerplant located on each wing tip, another hybrid-electric powerplant located at outboard location on each wing and a third hybrid-electric powerplant located at an inboard location on each wing. It is also envisioned that a hybrid-electric powerplant may be associated with the tail section of the aircraft. 
     The subject invention is also directed to an aircraft propulsion system that includes at least one electric powerplant and at least one combustion powerplant, wherein each powerplant delivers power to a respective air mover for propelling the aircraft. In one embodiment, an inboard heat engine and an outboard electric motor are associated with each wing of the aircraft. In another embodiment, an inboard heat engine and two outboard electric motors are associated with each wing, and a heat motor is associated with the tail section of the aircraft. 
     In yet another embodiment, three electric motors are distributed along each wing of the aircraft, and a heat motor is associated with the tail section of the aircraft. In another embodiment, each wing has a heat motor located on the leading edge side of the wing and an electric motor located on the trailing edge side of the wing, or vice versa. In yet another embodiment, a heat engine and an electric motor are associated with the tail section of the aircraft. 
     It is envisioned that the aircraft propulsion system can further include at least one hybrid-electric powerplant that includes a heat engine and an electric motor arranged in a parallel drive configuration or in an in-line drive configuration for delivering power to an air mover for propelling the aircraft. In one embodiment of such a system an inboard hybrid-electric powerplant is associated with each wing, an outboard electric motor is associated with each wing, and a heat engine is associated with the tail section of the aircraft. 
     In another embodiment of such a system an inboard heat engine is associated with each wing, two outboard electric motors are associated with each wing, and a hybrid-electric powerplant is associated with the tail section of the aircraft. In yet another embodiment of such a system each wing has a heat motor located on the leading edge side of the wing and an electric motor located on the trailing edge side of the wing, and a hybrid-electric powerplant is associated with the tail section of the aircraft. 
     In accordance with the subject invention, it is envisioned that the propulsive power provided by a particular propulsion configuration to propel the aircraft could be evenly distributed amongst several powerplants of the propulsion system or the propulsive power provided by a particular propulsion configuration can be distributed proportionally amongst several powerplants of the propulsion system. 
     More particularly, the subject invention is directed to an aircraft propulsion system that includes a plurality of hybrid-electric powerplants for delivering power to respective air movers to propel the aircraft, wherein each hybrid-electric powerplant includes a heat engine and an electric motor that are arranged in a parallel drive configuration or in an in-line drive configuration. In certain embodiments, the propulsive power provided to the air movers is evenly distributed amongst the plurality of hybrid-electric powerplants, and in other embodiments the propulsive power provided to the air movers is proportionally distributed amongst the plurality of hybrid-electric powerplants. 
     The subject invention is also directed to an aircraft propulsion system that includes a plurality of powerplants for delivering power to respective air movers to propel the aircraft, wherein each powerplant includes a heat engine and/or an electric motor. In certain embodiments, the propulsive power provided to the air movers is evenly distributed amongst the plurality of powerplants, and in other embodiments the propulsive power provided to the air movers is proportionally distributed amongst the plurality powerplants. 
     These and other features of the aircraft propulsion systems of the subject invention will become more readily apparent to those having ordinary skill in the art to which the subject invention appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that those having ordinary skill in the art will readily understand how to make and use the subject invention without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein: 
         FIG. 1  is a top plan view of a commercial passenger aircraft with which an embodiment of a distributed propulsion system configured in accordance with the subject invention is deployed; 
         FIG. 2  is a front elevational view pf the aircraft illustrated in  FIG. 1 ; 
         FIG. 3  is a left side front elevational view of the aircraft illustrated in  FIG. 1 ; 
         FIG. 4  is a schematic representation a hybrid-electric propulsion system deployed in several of the embodiments of the invention described herein, which includes an electric motor (eM) and a heat engine (hM) arranged in a parallel drive configuration; 
         FIG. 5  is a schematic diagram of an aircraft having a single hybrid-electric propulsion system located on each wing, wherein a battery is required; 
         FIG. 6  is a schematic diagram of an aircraft having three hybrid-electric propulsion systems located on each wing, wherein a battery is required; 
         FIG. 7  is a schematic diagram of an aircraft having an inboard heat engine and an outboard electric motor located on each wing, wherein a battery is required; 
         FIG. 8  is a schematic diagram of an aircraft having an inboard heat engine and two outboard electric motors located on each wing, and a heat engine associated with the tail section of the aircraft, wherein a battery is required; 
         FIG. 9  is a schematic diagram of an aircraft wherein each wing has a heat motor located on the leading edge side of the wing and an electric motor located on the trailing edge side of the wing, and wherein a battery is required; 
         FIG. 10  is a schematic diagram of an aircraft having three electric motors distributed along each wing and having a heat engine associated with the tail section of the aircraft, wherein a battery is required; 
         FIG. 11  is a schematic diagram of an aircraft having three electric motors distributed along each wing and having a hybrid-electric propulsion system associated with the tail section of the aircraft, wherein a battery is optional; 
         FIG. 12  is a schematic diagram of an aircraft having a heat engine and an electric motor associated with the tail section of the aircraft, wherein a battery is required; 
         FIG. 13  is a schematic diagram of an aircraft having a hybrid-electric propulsion system on each wing and another hybrid-electric propulsion system associated with the tail section of the aircraft, wherein a battery is required; 
         FIG. 14  is a schematic diagram of an aircraft having three hybrid-electric propulsion systems distributed along each wing and having another hybrid-electric propulsion system associated with the tail section of the aircraft, wherein a battery is required; 
         FIG. 15  is a schematic diagram of an aircraft having an inboard hybrid-electric propulsion system and an outboard electric motor located on each wing, and having a heat engine associated with the tail section of the aircraft, wherein a battery is optional; 
         FIG. 16  is a schematic diagram of an aircraft having an inboard heat engine and two outboard electric motors located on each wing, and having a hybrid-electric propulsion system associated with the tail section of the aircraft, wherein a battery is optional; 
         FIG. 17  is a schematic diagram of an aircraft wherein each wing has a heat motor located on the leading edge side of the wing and an electric motor located on the trailing edge side of the wing, and wherein a hybrid-electric propulsion system is associated with the tail section of the aircraft, and a battery is optional; and 
         FIG. 18  is a schematic diagram of an aircraft wherein each wing has an inboard heat motor located on the leading edge side of the wing and an inboard electric motor located on the trailing edge side of the wing, along with an outboard electric motor located on each wing, and wherein a heat engine is associated with the tail section of the aircraft, and a battery is required. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings wherein like reference numerals identify similar structures or features of the subject invention, there illustrated in  FIGS. 1 through 3  a commercial passenger aircraft  10  that includes a fuselage  12 , left and right wings  14  and  16  and a tail section  18  that has a vertical stabilizer  20 , which includes left and right horizontal stabilizers  22  and  24 . 
     In the description that follows, the aircraft  10  may include one or more powerplant locations on each wing  14 ,  16 , with these powerplant locations being numbered sequentially from left to right as is conventional, whereby the left-most powerplant location on wing  14  will always be designated herein as location number one. In certain embodiments described below, additional powerplants will be located in the tail section of the aircraft. 
     In the description that follows, there will be certain propulsion configurations that include one or more Hybrid-Electric Powerplants (HEP). As shown in  FIG. 4 , each HEP is designated generally by reference numeral  100  and it includes an electric motor (eM)  110  and a heat engine or heat motor (hM)  112 . The electric motor  110  and the heat engine  112  of each HEP are arranged in a parallel drive configuration. Alternatively, the electric motor  110  and the heat engine of each HEP are arranged in an in-line drive configuration. The power delivery from each HEP can be about evenly split between the electric motor  110  and the heat engine  112  (i.e., 50:50), or the power delivery from each HEP can be proportionally split between the electric motor  110  and the heat engine  112  (e.g., from 90:10 to 10:90). 
     A battery system provides energy to the electric motor  110  of the HEP, and it is envisioned that the battery system could be located within the fuselage  12  of the aircraft  10  and/or within the wings  14 ,  26  of the aircraft  10 , or in other locations that provide the required installation space and adjacency of the used electrical power. 
     With continuing reference to  FIG. 4 , the HEP further includes a Motor Controller (MC)  114  and an Engine Control Unit (ECU)  115  which communicate with one another by way of a communication network such as a CAN Bus or the like. The HEP receives control input from the pilot by way of a Power Lever Angle (PLA) throttle  116  located on the flight deck of the aircraft  10 . The HEP further includes a Propeller Control Unit (PCU)  118  for air mover or propeller  113  that receives input from the pilot by way of a Condition Lever Angle (CLA) throttle  120  located on the flight deck of the aircraft  10 . 
     It is envisioned that the heat engine  112  of the HEP could be configured as a gas turbine, a spark ignited, a diesel, a rotary engine or a reciprocating engine of any fuel type with a configuration of turbomachinery elements, selected from a group consisting of a turbocharger, turbo-supercharger, or supercharger and exhaust recovery turbo compounding, which is mechanically, electrically, hydraulically or pneumatically driven. An example of a rotary engine suitable for such an application is disclosed in U.S. Pat. No. 10,145,291, the disclosure of which is herein incorporated by reference in its entirety. 
     In the description that follows, there will also be certain propulsion configurations that include one more powerplants that have only an electric motor (eM), one or more powerplants that have only a heat engine (hM), or one more powerplants that have a heat motor (hM) in a forward or leading edge position and an electric motor (eM) in an aft or trailing edge position, or vice versa. In some of these configuration a battery is required to provide power to the electric motor(s) and in other configurations a battery would be optional. 
     In accordance with the subject invention, it is envisioned that the propulsive power provided by the propulsion system to propel the aircraft can be evenly distributed amongst several powerplants of the propulsion system. Alternatively, the propulsive power provided by the propulsion system can be distributed proportionally amongst several powerplants of the propulsion system. In each instance, proportional propulsive power within a particular propulsion system would be achieved by selectively sizing the electric motors and/or heat engines to generate a desired amount of propulsive power. 
     Referring to  FIG. 5 , there is illustrated an aircraft  205  having a single hybrid-electric propulsion system HEP located on each wing. More particularly, an HEP is located in position  1  on the left wing  14  of aircraft  205  for delivering power to an air mover to propel the aircraft  205 , and an HEP is located in position  2  on the right wing  16  of aircraft  205  to deliver power to an air mover to propel the aircraft  205 . Preferably, the propulsive power to propel aircraft  205  would be evenly distributed between the HEPs in positions  1  and  2 . 
     In this configuration, a battery is required to provide power to the electric motors of the HEP on each wing. It is envisioned that in the event of a failure of one hM in one HEP, power from the healthy hM in the other HEP can be extracted with its associated eM and transferred to the eM of the HEP with the failed hM so as to balance load from one wing to the other. This power transfer concept can be extended to other embodiments of the invention presented herein below. 
     Referring to  FIG. 6 , there is illustrated an aircraft  206  having three HEP systems located on each wing. More particularly, an HEP is located in positions  1 - 3  on the left wing  14  of aircraft  206  to deliver power to respective air movers to propel the aircraft  206 , and an HEP is located in positions  4 - 6  on the right wing  16  of aircraft  206  to deliver power to respective air movers to propel the aircraft  206 . 
     The propulsive power to propel aircraft  206  could be evenly distributed amongst the powerplants in positions  1  through  6 , or power could be proportionally distributed amongst the six powerplants. For example, the propulsive power generated by the HEP in the two outboard-most positions  1  and  6  could be proportionally less than the propulsive power generated by the HEP in each of the inboard positions  2  through  5 . A battery is required to provide power to the electric motor in each of the six HEP positions of aircraft  206 . In the event of a low battery or battery depletion condition, it is envisioned that one HEP could act as a generator. This power generation concept could be applied in other embodiments of the invention disclosed herein. 
     Referring to  FIG. 7 , there is illustrated an aircraft  207  having an inboard heat engine hM and an outboard electric motor eM located on each wing. More particularly, an electric motor eM is located in position  1  on the left wing  14  of aircraft  207  and a heat engine hM is located in position  2  on the left wing  14  of aircraft  207 . Similarly, a heat engine is located in position  3  on the right wing  16  of aircraft  207  and a heat engine hM is located in position  4  on the right wing  16  of aircraft  207 . In this configuration, a battery is required to provide power to the electric motor eM on each wing of aircraft  207 . 
     Referring to  FIG. 8 , there is illustrated an aircraft  208  having two outboard electric motors eM at locations  1  and  2  on left wing  14  and an inboard heat engine hM at location  3  on left wing  14 . Similarly, an inboard heat engine hM is located in position  4  on right wing  16  of aircraft  208  and two outboard electric motors eM are located in positions  5  and  6  on right wing  16  of aircraft  208 . In addition, a heat engine hM is associated with the tail section  18  of the aircraft  208  for delivering power to a respective air mover. It is envisioned that an eM in this configuration could be used as a Ram Air Turbine (RAT) in case of an emergency. In this embodiment, a battery is required to provide power to each of the electric motors on each wing of aircraft  208 . 
     Referring to  FIG. 9 , there is illustrated an aircraft  209  having a heat motor hM located on the leading edge side of position  1  of the left wing  14  and an electric motor eM located on the trailing edge side of position  1  of the left wing  14 . Similarly, a heat engine hM is located on the leading edge side of position  2  of the right wing  16  and an electric motor eM is located on the trailing edge side of position  2  of the right wing  16 . In this embodiment of the invention, each heat engine and each electric motor delivers power to a respective air mover to propel the aircraft  209 . It is also envisioned that the electric motors could be located on the leading edge side of wings and the heat engines could be located on the trailing side of each wing. In addition, a battery is required to provide power to each of the electric motors on each wing of aircraft  209 . 
     Referring to  FIG. 10 , there is illustrated an aircraft  210  having three electric motors eM distributed along each wing of aircraft  210  and a heat engine hM associated with the tail section  18  of the aircraft  210 . More particularly, an electric motor eM is located in positions  1 - 3  on the left wing  14  of aircraft  210  to deliver power to respective air movers to propel the aircraft  210 , and an electric motor eM is located in positions  4 - 6  on the right wing  16  of aircraft  210  to deliver power to respective air movers to propel the aircraft  210 . 
     Those skilled in the art will readily appreciate that more than three electric motors can be distributed along each wing. For example, there could be four, five or even six or more electric motors distributed along each wing of an aircraft. In addition, in the propulsion configuration of aircraft  210 , a heat engine hM is associated with the tail section  18  of the aircraft  210 . 
     It is envisioned that the propulsive power to propel aircraft  210  could be evenly distributed amongst the electric motors (eM) located in positions  1  through  6 , or power could be proportionally distributed amongst these six powerplants. For example, the propulsive power generated by the eM in the two outboard-most positions  1  and  6  could be proportionally less than the propulsive power generated by the eM in each of the inboard positions  2  through  5 . A battery is required to provide power to the six electric motors of aircraft  210 . 
     Referring to  FIG. 11 , there is illustrated an aircraft  211  having three electric motors eM distributed along each wing of aircraft  211  and a hybrid-electric propulsion system HEP associated with the tail section  18  of the aircraft  211 . More particularly, an electric motor eM is located in positions  1  through  3  on the left wing  14  of aircraft  211  to deliver power to respective air movers to propel the aircraft  211 , and an electric motor eM is located in positions  4  through  6  on the right wing  16  of aircraft  211  to deliver power to respective air movers to propel the aircraft  211 . In addition, a hybrid-electric propulsion system HEP is associated with the tail section  18  of the aircraft  211 . In this embodiment of the invention, propulsive power could be evenly distributed or proportionally distributed amongst each of the electric motors and it is envisioned that a battery would be optional. 
     Referring to  FIG. 12 , there is illustrated an aircraft  212  having a heat engine hM is associated with the left horizontal stabilizer  22  of the tail section  18  of aircraft  212  and an electric motor eM is associated with the right horizontal stabilizer  24  of the tail section  18  of aircraft  212 . It is envisioned that propulsive power would be evenly distributed amongst the heat engine and the electric motor on aircraft  212 . In this embodiment of the invention, a battery is required to provide power to the electric motor of aircraft  212 . 
     Referring to  FIG. 13 , there is illustrated an aircraft  213  having a single hybrid-electric propulsion system HEP located on each wing and another hybrid-electric propulsion system HEP associated with the tail section  18  of aircraft  213 . More particularly, an HEP is located in position  1  on the left wing  14  of aircraft  213  for delivering power to an air mover to propel the aircraft  213 , and an HEP is located in position  2  on the right wing  16  of aircraft  213  to deliver power to an air mover to propel the aircraft  213 . In addition, a third HEP is associated with the tail section  18  of aircraft  213  to deliver power to a respective air mover to propel the aircraft  213 . 
     It is envisioned that propulsive power could be evenly distributed amongst each HEP on aircraft  213  or propulsive power could be proportionally distributed, whereby the HEP on each wing  14 ,  16  would provide more propulsive power than the third HEP located in the tail section  18  of aircraft  213 . It is envisioned that the HEP in the tail section  18  of aircraft  213  could be adapted to generate engine power and transfer it to the on-wing HEPs. In this configuration, a battery is required to provide power to the electric motors in the HEP on each wing  14 ,  16  and in the tail section  18  of aircraft  213 . 
     Referring to  FIG. 14 , there is illustrated an aircraft  214  having three HEP systems located on each wing and another hybrid-electric propulsion system HEP associated with the tail section  18  of aircraft  214 . More particularly, an HEP is located in positions  1  through  3  on the left wing  14  of aircraft  214  to deliver power to respective air movers to propel the aircraft  214 , and an HEP is located in positions  4  through  6  on the right wing  16  of aircraft  214  to deliver power to respective air movers to propel the aircraft  214 . Those skilled in the art will readily appreciate that more than three HEP drive systems could be distributed along each wing. For example, there could be four, five or even six or more HEP drive systems distributed along each wing of an aircraft. In addition, on aircraft  214 , a seventh HEP is located the tail section  18  of aircraft  214  to deliver power to a respective air mover to propel the aircraft  214 . 
     It is envisioned that propulsive power on aircraft  214  could be evenly distributed amongst each HEP or propulsive power could be proportionally distributed amongst each HEP. For example, the HEP in the tail section  18  of aircraft  214  could provide proportionally less propulsive power than each other HEP located in the six positions of wings  14  and  16 . In this configuration, a battery is required to provide power to the electric motors in the HEP on each wing  14 ,  16  and in the tail section  18  of aircraft  214 . It is further envisioned, that in the event of a low battery or battery depletion condition, an HEP could act as a generator to supply electric power to the eM of another HEP on the aircraft  214 . 
     Referring to  FIG. 15 , there is illustrated an aircraft  215  having an inboard hybrid-electric propulsion system HEP and an outboard electric motor eM located on each wing of aircraft  215 . More particularly, an electric motor eM is located in position  1  on the left wing  14  of aircraft  215  and a hybrid-electric propulsion system HEP is located in position  2  on the left wing  14  of aircraft  215 . Similarly, a hybrid-electric propulsion system HEP is located in position  3  on the right wing  16  of aircraft  215  and an electric motor eM is located in position  4  on the right wing  16  of aircraft  215 . In addition, a heat engine hM is associated with the tail section  18  of the aircraft  215  to deliver power to a respective air mover to propel the aircraft  215 . In this embodiment of the invention, it is envisioned that a battery would be optional. 
     Referring to  FIG. 16 , there is illustrated an aircraft  216  having two outboard electric motors eM located at positions  1  and  2  on left wing  14  and an inboard heat engine hM located at position  3  on left wing  14 . Similarly, an inboard heat engine hM is located in position  4  on right wing  16  of aircraft  216  and two outboard electric motors eM are located in positions  5  and  6  on right wing  16  of aircraft  216 . In addition, a hybrid-electric propulsion system HEP is associated with the tail section  18  of the aircraft  216  to deliver power to a respective air mover to propel the aircraft  216 . In this embodiment of the invention, it is envisioned that a battery would be optional. 
     Referring to  FIG. 17 , there is illustrated an aircraft  217  having a heat motor hM located on the leading edge side of position  1  of the left wing  14  and an electric motor eM located on the trailing edge side of position  1  of the left wing  14 . Similarly, a heat motor hM is located on the leading edge side of position  2  of the right wing  16  and an electric motor eM is located on the trailing edge side of position  2  of the right wing  16 . In addition, a hybrid-electric propulsion system HEP is associated with the tail section  18  of the aircraft  217 . In this embodiment of the invention, the hybrid-electric propulsion system HEP, each heat engine hM and each electric motor eM deliver power to a respective air mover to propel the aircraft  217 . In this embodiment of the invention, it is envisioned that a battery would be optional. 
     Referring to  FIG. 18 , there is illustrated an aircraft  218  having an electric motor eM located in position  1  associated with the wing tip of the left wing  14 , a heat motor hM located on the leading edge side of position  2  of the left wing  14  and an electric motor eM located on the trailing edge side of position  2  of the left wing  14 . Similarly, a heat motor hM is located on the leading edge side of position  3  of the right wing  16 , an electric motor eM is located on the trailing edge side of position  3  of the right wing  16 , and an electric motor eM is located in position  4  associated with the wing tip of the right wing  16 . In addition, a heat engine hM is associated with the tail section  18  of the aircraft  218 . In this embodiment of the invention, each heat engine hM and each electric motor eM deliver power to a respective air mover to propel the aircraft  218 . In this embodiment of the invention, a battery is required to provide power to the electric motors of aircraft  218 . 
     While the subject disclosure has been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.