WO2018106137A2

WO2018106137A2 - Distributed electric propulsion system and vertical take-off and landing aircraft

Info

Publication number: WO2018106137A2
Application number: PCT/RO2017/050001
Authority: WO
Inventors: Giurca LIVIU GRIGORIAN
Original assignee: Liviu Grigorian Giurca
Priority date: 2016-11-17
Filing date: 2017-10-23
Publication date: 2018-06-14
Also published as: WO2018106137A3; WO2018106137A4; RO132565A2

Abstract

The present invention relates to a distributed electric propulsion system and vertical take-off and landing ("VTOL") aircraft and especially to this having hybrid or electric drive, used to transport people or goods from one point to the other without the necessity of airport runways. A vertical take-off and landing aircraft (60) utilizes a distributed electric propulsion system (61) comprising at least two propellers with total vectoring (62) located at the ends of two fixed wings (63), the wings (63) being mounted on one side and the other of an fuselage (64). Each propeller with total vectoring 62 is driven in rotation motion by a shaft (68) and by an actuator. The three main operating modes of the aircraft (60), respectively vertical, transition and forward flight, are achieved by inclined in different positions the propellers with total vectoring (62).

Description

DISTRIBUTED ELECTRIC PROPULSION SYSTEM AND VERTICAL TAKE-OFF AND LANDING AIRCRAFT

Cross-Reference to Related Application

This application claims the benefit of Romanian Provisional Application A/00844/2016 filed November 17, 2016 and incorporated by reference in its entirety.

Technical Field

The present invention relates to a distributed electric propulsion system and vertical take-off and landing ("VTOL") aircraft and especially to this having hybrid or electric drive, used to transport people or goods from one point to the other without the necessity of airport runways.

Background Art

The VTOL aircraft combines the advantages of helicopter, respectively the ability to flight vertically with the advantages of the conventional (fixed wings) aircraft, respectively the high speed in forward flight and the high efficiency of the travel. Even some solutions were proposed, a significant progress was not yet obtained.

An innovative solution was applied by Aurora Flight Sciences which proposed to use a number of ducted fans, acted electrically, located on the main wings and on the Canard wings (front wings). This solution has the drawback that the heavy wings are acted by a very complicate and heavy mechanism. On the other hand the presence of the side wind cannot be compensated, in which case the functional safety is affected. This type of propulsion cannot be used by large and very large aircraft.

A similar solution was proposed by the German company Lilium GMBH, having same disadvantages.

Another solution is described by the patent application US20160167776 which proposes the use of four open air fans for a vertical take-off and landing aircraft (figures 26A and 26E). In this case, in the event of a fan failure, the aircraft loses its stability, so the system has not redundancy. In addition, the frame that supports the rotors can be rotated only around a single axis and it is not possible to compensate the side winds.

Consequently, it becomes a necessity to achieve a very efficient redundancy system in all flight conditions, applicable to large and very large aircraft and to compensate for the influence of the side winds on take-off and landing. Disclosure of the Invention

The invention eliminates the disadvantages shown above in that a vertical take-off and landing aircraft uses a distributed electric propulsion system comprising at least two propellers with total vectoring of the air jet, fixed at the ends of two fixed wings, the wings being mounted side by side of a fuselage. The two propellers with total vectoring offer the possibility that the air jet is progressively oriented in two main directions. To accomplish this, the propellers with total vectoring use a C- shaped frame that comprises in the middle a multiple propeller, of the type with jet amplifier or of the simply type consisting of several ducted fans, arranged in line. The multiple propellers can be rotated around an axis perpendicular to the median plane of the fuselage, called the main axis and an axis located along the multiple propeller called the second axis. Depending on the flight mode of the aircraft, the multiple propellers can rotate at a specific angle around the main axis, depending on each mode, respectively in the vertical flight, the transition period and the forward flight. In the event of a side wind, the multiple propellers can be rotated with a specific angle around the secondary axis to maintain the stability of the aircraft. The fixed wings have an all-round aerodynamic profile and are used in horizontal flight. In a first embodiment, each fixed wing has a three-segment configuration, respectively the first horizontal fixing segment substantially located in a horizontal plane is mounted in the median plane of the fuselage. The horizontal fixing segment continues with an inclined segment that connects with a final horizontal segment. The final horizontal segment is located above the top of the fuselage, which guarantees the positioning of the propellers with total vectoring overhead of the aircraft.

In another embodiment, a propeller with total vectoring may employ a T-shaped frame on which two separate multiple propellers are attached.

In a third embodiment, a propeller with total vectoring may employ a T-shaped frame on which a plurality of at least four electric motors, each of them acting in a certain sense to rotate a rotor. Symmetrically, on the other side, an equal number of electric motors are fixed which act other rotors in the opposite direction of rotation with the ones described above.

A fourth variant is represented by a propeller with partial vectoring that has the ability to rotate only around the main axis.

In another embodiment, an aircraft with a reinforced structure supports two propellers with total vectoring located at the ends of the reinforced wings, between the end horizontal segments being fixed a connecting wing, also having an aerodynamic profile, the connecting wing contributing to increase the lift force in the forward flight. In another variant, two fixed wings, which carry two propellers with total vectoring, are directly fixed to the top of the fuselage.

In another embodiment two propellers with partial vectoring are supported by two rear wings fixed at the top of the fuselage and two other propellers with partial vectoring are supported by two front wings fixed in the middle area of the fuselage and to the front of the fuselage. The front wings have a different length compared with the rear wings in such a way that the air jet created during the horizontal flight of the front multiple propellers does not interfere with the jet of the rear multiple propellers.

In another embodiment, two propellers with total vectoring are supported by two rear wings of the segmented type, and two propellers with partial vectoring are mounted directly on the fuselage. On the two propellers with partial vectoring are fixed two wings of Canard type which are used to stabilize the aircraft in the forward flight.

In another embodiment, an individual aircraft has a metallic frame on which two propellers with partial vectoring are attached to the top. A person can be transported inside the metal frame. On each propeller with partial vectoring wing is fixed a wing considered to be inferior. Between the two propellers with partial vectoring another wing is fixed which is considered superior. All inferior and superior wings rotate simultaneously by means of the propellers with partial vectoring depending on the aircraft flight regime.

Advantages of the inventions

The invention has a number of important advantages or unexpected positive effect comparing with the state of the art, that are:

- The propellers with total vectoring improve aircraft stability in case of side wind;

- The propellers with total or partial vectoring show a high level of redundancy;

- Passenger or commuter aircraft using the distributed electric propulsion system mainly have a fuselage similar to that of fixed-wing aircraft and therefore the fabrication technology is similar; - The individual aircraft has a very simple configuration and a low cost;

- Airplanes using propellers with total or partial vectoring have a large number of constructive configurations depending on the distributed electric propulsion system used, starting with small or medium sized aircraft and ending with large or very large aircraft. Brief Description of Drawings

- Fig. 1, an isometric view of a propeller with total vectoring having ducted fans and a C-shaped frame;

- Fig. 2 is a side view of the propeller of Figure 1;

- Fig. 3, an isometric view of a propeller with total vectoring having ducted fans and a T-shaped frame;

- Fig. 4, an isometric view of a propeller with total vectoring having counter-rotating open rotors and a T-shaped frame;

- Fig. 5 is an isometric view of a segmented wing aircraft and two propellers with total vectoring in the take-off or landing phase;

- Fig. 6 is an isometric view of the aircraft of Figure 5 in the transition phase;

- Fig. 7 is an isometric view of the aircraft of Figure 5 in the horizontal flight phase;

- Fig. 8 is an isometric view of an aircraft with reinforced segmented wings and two propellers with total vectoring;

- Fig. 9 is an isometric view of an aircraft with segmented reinforced wings and two propellers with total vectoring having open counter-rotating rotors in the take-off or landing phase;

- Fig. 10 is an isometric view of an aircraft with two wings fixed to the upper part of the fuselage and two propellers with total vectoring;

- Fig. 11 is an isometric view of an aircraft with two wings fixed to the front of the fuselage and two wings fixed in the rear part of the fuselage having four propellers with partial vectoring;

- Fig. 12 is an isometric view of an aircraft with two wings at the front of the fuselage and two wings fixed in the rear part of the fuselage, having two propellers with partial vectoring, supporting the front wings, and two propellers with total vectoring;

- Fig. 13 is an isometric view of an individual aircraft in the take-off or landing phase;

- Fig. 14 is an isometric view of the aircraft of Figure 14 in the horizontal flight phase.

Best Mode for Carrying Out the Invention

A propeller with total vectoring 1 comprises a multiple propeller 2 with thrust amplifier mounted on a C-shaped frame 3 by means of two rotating shafts 4 mounted on two joints 5, as in figures 1 and 2. The shafts 4 are actuated by some actuators (not shown). The frame 3 presents in the middle a shaft 6 which is also rotatable. The multiple propeller 2 with flow amplifier contains a number of ducted fans 7 which can rotate each in a duct 8. Each fan 7 is driven by an electric motor 9. The ducts 8 are tangential to each other and form a duct block 10. The duct block 10 is surrounded by an envelope ring 11 which supports the duct block 10 by means some ribs 12. If the envelope ring 11 lacks the multiple propeller is of the simple type and the frame 3 directly supports the duct block 10. The multiple propeller 2 can be rotated around an axis coinciding with the axis of the shaft 6, called the main axis A, and in this case the rotation angle is ± 90 °. Also, the multiple propeller 2 can be rotated around an axis located along the multipurpose propeller called the secondary axis B, and in this case the angle of rotation at the left a can be different from the right rotation angle β depending on the geometric limitations (figure 2). The propeller with total vectoring 1 presents the possibility that the air jet produced by the fans 7 is progressively oriented in two different directions.

In a second embodiment, a propeller with total vectoring 20 comprises two multiple propellers 21 located in line as in figure 3. Between the two multiple propellers 21 there is a joint 22 which sustains two shafts 23, each connected with one multiple propeller 21. The rotary shafts 23 are actuated by an actuator (not shown). The joint 22 is solidary with a rotary shaft 24. The shaft 24 and the multiple propellers 21 are T-shaped. The multiple propellers 21 can be rotated around an axis coinciding with that of the shaft 24, called the main axis D, and also the multiple propellers 21 can be rotated around an axis located along the shafts 23 called the secondary axis E. The propeller with total vectoring 20 presents the possibility that the produced air jet is progressively oriented after the two different directions.

In a third embodiment, a propeller with total vectoring 40 utilizes a T-shaped frame 41 on which are fixed at one side a plurality of electric motors 42 acting in rotation motion some rotors 43 as shown in figure 4. Symmetrically, on the other side, an equal number of electric motors 44 are fixed which acts other rotors 45 in the opposite direction of rotation relative to the rotors 43. The frame 41 presents in the middle a joint 46 from which two shafts 47 are symmetrically driven and are actuated by an actuator (not shown). Another shaft 48 is solidary with the joint 46. The totality of the electric motors 42 and 44, respectively of the rotors 43 and 45 forms together a multiple propeller 50 of the open type. The multiple propeller 50 can be rotated around an axis coinciding with that of the shaft 48 called the main axis F and also the multiple propeller 50 can be rotated around an axis located along the shafts 47 called the secondary axis G. The propeller with total vectoring 40 has the possibility that the produced air jet is progressively oriented in two different directions.

If any one of the previous variants suppresses the rotation of the multiple propeller after the secondary axis, a propeller with partial vectoring (not shown) is obtained. In the case of the propeller with partial vectoring the rotation is made after a single axis, respectively, along the main axis and in operation the produced air jet is progressively oriented after a single main direction.

The propeller with total vectoring and the propeller with partial vectoring can be used in various combinations on different types of aircraft. A vertical take-off and landing aircraft 60 utilizes a distributed electric propulsion system 61 formed by at least two propeller with total vectoring 62 located at the ends of two fixed wings 63, the wings 63 being mounted on one side and the other of a fuselage 64 as in figures 5, 6 and 7. The wings 63 have an aerodynamic profile and are used in the horizontal flight. In a first embodiment, each wing 63 has a three-segment configuration and a first horizontal fixing segment 65 substantially located in a horizontal plane is mounted in the median plane of the fuselage 64. The horizontal fixing segment 65 continues with an inclined segment 66 which connects with a final horizontal segment 67. The final horizontal segment 67 is located above the topmost point of the fuselage 64 which guarantees the positioning of the propellers with total vectoring 62 above the center of gravity of the aircraft 60. Each propeller with total vectoring 62 is driven in rotation motion by a shaft 68 and by an actuator (not shown). In operation, at the time of take-off or landing, the propellers with total vectoring 62 are oriented in the vertical direction, respectively expelling the air jet downwardly as in figure 5. In the case of side wind, the propellers with total vectoring 62 are inclined along the secondary axis to compensate for the forces exerted on the aircraft 60. During the transition from the vertical flight to the horizontal flight and vice versa, the propellers with total vectoring 62 are inclined as in figure 6. As the speed of the aircraft 60 increases due to the horizontal component of the traction force developed by the propellers with total vectoring 62, the lift is taken over by the wings 63. When the propellers with total vectoring 62 reach the position in which they are perpendicular to the initial position, i.e. when the air jet is oriented in the horizontal direction, the aircraft is fully taken over by wings 63 as shown in figure 7. The system with distributed electric propulsion 61 can also be built with the other types of total or partial vectoring propellers described above.

In a second embodiment an aircraft 90 has a reinforced structure as shown in figure 8. In this case, the two propellers with total vectoring 62 are mounted at the ends of two reinforced wings 91. Between the ends of two horizontal segments 67 of each reinforced wing 91 is fixed a connecting wing 92 having also an aerodynamic profile, the connecting wing 92 contributing to the increase of the lifting force in the forward flight of the aircraft 90.

In a third embodiment an aircraft 101 uses two reinforced wings 102, on which two propellers with total vectoring 103 of the type with open rotors are mounted, as is shown in figure 9. Each propeller with total vectoring 103 is driven in rotation motion by means of a shaft 104 and by an actuator (not shown).

In a fourth embodiment, an aircraft 110 uses two wings 111, directly attached to the top of a fuselage 112, the wings 111 supporting two propellers with total vectoring 113 as in figure 10. In a fifth embodiment, an aircraft 120 uses two propellers with partial vectoring 121 supported by two rear wings 122 fixed to the top of a fuselage 123, and two other propellers with partial vectoring 124 which are supported by two front wings 125 fixed in the middle area o a fuselage 123 as in figure 11. The front wings 125 have a different length compared with the rear wings 122 so that the air jet created during the forward flight by the propellers with partial vectoring 124 does not interfere with the air jet of the propellers with partial vectoring 121.

All aircraft described above can use any type of total or partial vectoring propellers.

In a sixth embodiment, an aircraft 140 uses at the rear a reinforced wing 141 mounted at the rear of a fuselage 142, at the ends of the wing 141 being mounted two propellers with total vectoring 143 as in figure 12. At front side of the fuselage 142 are symmetrically mounted two propellers with partial vectoring 144 that can rotate on two shafts 145, driven by two actuators (not shown). On the propellers with partial vectoring 121 are fixed some wings 146 which are constituted for the aircraft 140 in a Canard-type solution and use to stabilize the aircraft in the horizontal flight. During the takeoff, the wings 146 are oriented in a vertical position and in the horizontal flight the wings 146 are substantially oriented in a forward position.

All types of aircraft described operate similarly to the one described in the first instance, respectively when taking off and landing the total or partially vectoring propellers have the air jets directed in the direction of down. During the transition period the air jets are inclined and during the forward flight the air jets are oriented horizontally by turning the propellers with total or partial vectoring.

In a seventh embodiment, an individual aircraft 160 comprises a metal frame 161 on which two propellers with partial vectoring 162 are attached to the top of the frame 161. Inside the frame 161 a pilot 164 may be transported in a standing position (or seated) as in figures 13 and 14. On each propeller with partial vectoring 162 there is fixed a wing 165 considered to be inferior. Between the two propellers with partial vectoring 162 is a wing 167, considered superior. All the superior wing 167 and the inferior wings 165 rotate simultaneously with the propellers with partial vectoring 162 depending on the flight mode of the aircraft 160. During the take-off and landing, the propellers with partial vectoring 162 have air jets directed in the direction of the down. During the forward flight the air jets are oriented horizontally by rotation of the partial vector propulsion 162 and the frame 161 is inclined due to the aerodynamic force exerted on its surface and on the pilot 164 exposed surfaces.

In all variants, the electrical energy required to drive the propellers with total or partial vectoring is provided by a set of electric batteries or in another case by a hybrid electric system. Any possible combinations of the above described solutions may be considered as part of the description and claims.

Claims

1. A distributed electric propulsion system wherein it employs at least two propellers with total vectoring (1), each comprising a multiple propeller (2), with thrust amplifier, suspended on a r shaped frame (3) by means of two rotating shafts (4) which are mounted in two joints (5), and the rotary shafts (4) are actuated by some actuators, and the frame (3) presents in the middle a shaft (6) which is also rotatable, and the multiple propeller (2) with thrust amplifier comprises a plurality of ducted fans (7), which can rotate each in a duct (8), each fan (7) being driven by an electric motor (9), and the ducts (8) are tangent together and form a duct block (10), and the duct block (10) is surrounded by an envelope ring (11) supporting the duct block (10) by means some ribs (12), and the multiple propeller (2) can rotate along an axis coinciding with the axis of the shaft (6), called the main axis A, in which case the rotation angle is ± 90 °, and the multiple propeller (2) can rotate along an axis located along the multiple propeller (2) called the secondary axis B, and in this case the angle of rotation at left a may be different from the angle of rotation to the right β depending on the geometric limitations, and the propeller with total vectoring (1) presents the possibility that the air jet produced by the fans (7) can be progressively oriented in two different directions.

2. A system as claimed in claim 1 wherein the multiple propeller is of the simple type and the frame (3) directly supports the duct block (10).

3. A system as claimed in claim 1 wherein it uses at least two propellers with total vectoring (20) each comprising two multiple propellers (21) arranged in line, and between the two multiple propellers (21) there is a joint (22), out of which two shafts (23) are connected with the multiple propellers (21), and the rotating shafts (23) are actuated by an actuator, and the joint (22) is solidary with a rotary shaft (24), and the shaft (24) and the multiple propellers (21) are placed in the T-shape, and the multiple propellers (21) can rotate along an axis which coincides with that of the shaft (24), called the main axis D, and multiple propellers (21) can rotate along an axis located along the shafts (23) called the secondary axis E, and the propeller with total vectoring (20) presents the possibility that the produced air jet is progressively oriented in two different directions.

4. A distributed electric propulsion system characterized in that it uses at least two propellers with total vectoring (40) utilizing a T-shaped frame (41) on which a number of electric motors (42) act in a certain sense of rotation some rotors (43), and symmetrically on the other side are an equal number of electric motors (44) which act other propellers (45), having the opposite direction of rotation relative to the rotors (43), and the frame (41) shows in the middle a joint (46) from which two shafts (47) emerge symmetrically, and the shafts (47) are actuated by an actuator, and a shaft (48) is solidary with the joint (46); the entirety of the electric motors (42) and (44) respectively all the rotors (43) and (45) form together a multiple propeller (50) of the open type, and the multiple propeller (50) can rotate along an axis coinciding with that of the shaft (48), called the main axis F, and the multiple propeller (50) can rotate along an axis located along the shafts (47) called the secondary axis G, and the propeller with total vectoring (40) presents the possibility that the produced air jet is progressively oriented in two different directions.

5. A system as claimed in claim 1, 2, 3 or 4, wherein it uses a propeller with partial vectoring at which the multiple propeller rotation is made after a single axis, respectively, along the main axis and in operation the produced air jet is progressively oriented after only the main direction.

6. Vertical take-off and landing aircraft as in claim 1, 2, 3, 4 or 5, characterized in that a vertical takeoff and landing aircraft (60) use a distributed electric propulsion system (61) comprising at least two propellers with total vectoring (62) located at the ends of two fixed wings (63), the wings (63) being mounted on one side of a fuselage (64), and the wings (63) have an aerodynamic profile and are used in the horizontal flight, and each wing (63) has a three-segment configuration, respectively a first horizontal fixing segment (65) substantially located in a horizontal plane and which is mounted in the median area of the fuselage (64), and the horizontal fixing segment (65) continues with a inclined segment (66) which connects with a final horizontal segment (67), and the final horizontal segment (67) is located above the top of the fuselage (64), which guarantees the positioning of the propellers with total vectoring (62) above the aircraft center of gravity (60), and each propeller with total vectoring (62) is driven in rotation motion by a shaft (68) and by an actuator.

7. An aircraft as claimed in claim 6 wherein an aircraft (90) has a reinforced structure and the two propellers with total vectoring (62) are mounted at the ends of two reinforced wings (91), between the horizontal segments (67) of each reinforced wing (91) being fixed a connecting wing (92) having also an aerodynamic profile, the connecting wing (92) contributing to the increase of the lift force in the forward flight of the aircraft (90).

8. An aircraft as claimed in claim 1, 2, 3, 4 or 5, characterized in that an aircraft (110) uses two wings (111) directly attached to the top of a fuselage (112) and supporting two propellers with total vectoring (113).

9. An aircraft as claimed in claim 1, 2, 3, 4 or 5, characterized in that an aircraft (120) uses two propellers with partial vectoring (121) supported by two rear wings (122) fixed to the top of a fuselage (123) and two other propellers with partial vectoring (124) are supported by two front wings (125) fixed in the median area of the fuselage (123), and the front wings (125) have a different length from the rear wings (122) so that the air jet created during the forward flight by the propellers with partial vectoring (124) does not interfere with the air jet of the propellers with partial vectoring (121).

10. An aircraft as claimed in claim 6, 7, 8 or 9, characterized in that during take-off or landing, the propellers with total vectoring (62) are oriented in the vertical direction, respectively expelling the air jet downwardly, and in the case of the existence of the side wind, the propellers with total vectoring (62) are also incline along the secondary axis to compensate the side forces exerted on the aircraft (60), and during the transition from the vertical flight to the forward flight and vice versa, the propellers with total vectoring (62) are inclined after the main axis, and as the speed of the aircraft (60) increases due to the horizontal component of the thrust force developed by the propellers with total vectoring (62), the lift is taken over by the wings (63), and when the propellers with total vectoring (62) reach the position in which they are

perpendicular to the initial position, i.e. when the air jet is oriented in the horizontal direction, the lift of the aircraft (60) is entirely taken over by the fixed wings (63) .

11. An aircraft as in claim 1, 2, 3, 4 or 5, characterized in that an aircraft (140) uses at the rear a reinforced wing (141) mounted at the rear of the fuselage (142), at the ends of the reinforced wing (141) being fixed with two propellers with total vectoring (143), and at the front side of the fuselage (142) are symmetrically mounted two propellers with partial vectoring (144) which can rotate on two shafts (145), being actuated by some actuators, and on the propellers with partial vectoring (144) are fixed some wings (146) which are constituted for the aircraft (140) in a Canard-type solution and use to stabilize the aircraft in the forward flight.

12. An aircraft as claimed in claim 11, characterized in that during the take-off the wings (146) are oriented in a vertical position and in the forward flight the wings (143) are oriented substantially in a horizontal position.

13. An aircraft as claimed in claim 5, characterized in that an individual aircraft (160) has a frame (161) on which two propellers with partial vectoring (162) are fixed at the top, and

Inside the frame (161) a pilot (164) can be transported in the standing position, and on each of the propellers with partial vectoring (162) there is fixed a wing (165) considered inferior, and a wing (167), considered superior, is fixed between the two propellers with partial vectoring (166), and all wings, the upper wing and the lower wings (165) rotate simultaneously with the propellers with partial vectoring (162) depending on the flight mode of the aircraft (160).

14. An aircraft as in claim 13 wherein in operation during the take-off and landing, the propellers with partial vectoring (162) have the air jets directed downwards, and during forward flight, the air jets are oriented horizontally by rotating the propellers with partial vectoring (162) and the frame (161) is inclined due to the aerodynamic force exerted on its surface and on the pilot (164) exposed surfaces.

15. A system as claimed in claim 6, 7, 8, 9, 11 or 13 wherein the energy required for the operation of the distributed electric propulsion system is provided by a set of accumulator batteries.

16. A system as in claim 6, 1, 8, 9, 11 or 13 wherein the energy required for the operation of the distributed electric propulsion system is provided by an electric hybrid system.