CN107672802B - Slotted duct type rotor wing aircraft with rolling flow - Google Patents

Slotted duct type rotor wing aircraft with rolling flow Download PDF

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Publication number
CN107672802B
CN107672802B CN201711000170.XA CN201711000170A CN107672802B CN 107672802 B CN107672802 B CN 107672802B CN 201711000170 A CN201711000170 A CN 201711000170A CN 107672802 B CN107672802 B CN 107672802B
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China
Prior art keywords
yaw
slotted
duct
rotating shaft
blade
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CN201711000170.XA
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Chinese (zh)
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CN107672802A (en
Inventor
雷良
徐起
肖升兴
沙伟
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Nanjing University of Aeronautics and Astronautics
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Nanjing University of Aeronautics and Astronautics
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/04Helicopters
    • B64C27/12Rotor drives
    • B64C27/16Drive of rotors by means, e.g. propellers, mounted on rotor blades
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/20Rotorcraft characterised by having shrouded rotors, e.g. flying platforms
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/32Rotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64CAEROPLANES; HELICOPTERS
    • B64C27/00Rotorcraft; Rotors peculiar thereto
    • B64C27/32Rotors
    • B64C27/46Blades
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64UUNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00Type of UAV
    • B64U10/10Rotorcrafts
    • B64U10/13Flying platforms
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64UUNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00Propulsion; Power supply
    • B64U50/10Propulsion
    • B64U50/13Propulsion using external fans or propellers
    • B64U50/14Propulsion using external fans or propellers ducted or shrouded
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B64AIRCRAFT; AVIATION; COSMONAUTICS
    • B64UUNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00Propulsion; Power supply
    • B64U50/10Propulsion
    • B64U50/19Propulsion using electrically powered motors

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  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Remote Sensing (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

The invention relates to a slotted duct type rolling rotor aircraft, which comprises a slotted duct, a rolling rotor, a supporting beam, a yaw control surface, a telescopic manipulator and an undercarriage, wherein the rolling rotor is a main lift structure, the slotted duct is an auxiliary lift structure, and the combination form not only can improve the lift of the aircraft to a great extent, but also can not generate reactive torque. The slotted ducted rotor craft is flexible and can be used as a module to perform related flight tasks such as transporting small objects or performing surveillance and investigation tasks.

Description

Slotted duct type rotor wing aircraft with rolling flow
Technical Field
The invention belongs to the technical field of aviation, and mainly relates to a slotted duct type plume rotor craft.
Background
The general fan-wing aircraft can generate larger low-pressure vortex in the cross flow fan through the high-speed rotation of the front edge cross flow fan of the wing type, so that larger pressure difference is generated on the upper surface and the lower surface of the front edge of the wing type, the fan-wing aircraft can generate larger lift force at the low speed, and the air flow is discharged to the rear edge to generate thrust. Unlike conventional fan aircraft, the rotor is configured to rotate the fan blades and drive the cross-flow fan using a power unit. Because the fan wings can provide great lifting force and forward thrust at low speed, the whole rolling rotor wing can realize autorotation without extra power. The biggest difference between the rotary wing with the rolling flow and the common rotary wing is that the rotary wing is autorotative, and the countertorque is balanced without adopting related measures, so that a plurality of transmission devices are reduced, the structure is simpler, and the weight is reduced. The wing type of the wing of the fan can hardly stall, so that the limitation of a stall attack angle is avoided, and the aerodynamic efficiency is higher. In addition, while the rotor can spin, it is quite different from a gyroplane. The autorotation gyroplane needs an external thrust device as forward power, and a certain forward flying speed is needed to realize the autorotation of the gyroplane, and hovering cannot be realized. While a plume rotorcraft does not require external devices to provide thrust, and hover may be achieved.
At the same angle of incidence, the induced speed of the rotor with the duct is greater than that of the isolated rotor, resulting in a reduction in the actual angle of attack of the blades in the duct, resulting in a reduction in the rotor drag, but the duct is also capable of generating a portion of additional lift, resulting in a total lift of the entire structure greater than that of the isolated rotor. Therefore, the reasonable design of the duct body is directly related to the overall performance of the duct rotor wing.
Disclosure of Invention
The invention aims to solve the technical problem of providing a slotted duct type plume rotor craft aiming at the defects related to the background technology.
The invention adopts the following technical scheme for solving the technical problems:
the slotted duct type plume rotor craft comprises a slotted duct, a plume rotor, a supporting beam and a yaw module;
the grooved duct is provided with a groove used for inhibiting the generation of blade tip vortex and reducing wing tip loss on the inner wall of the duct;
the support beam comprises a connecting ring and at least two support rods, wherein the connecting ring and the slotted duct are coaxially arranged; the support rods are uniformly arranged between the connecting rings and the slotted ducts, one ends of the support rods are fixedly connected with the connecting rings, and the other ends of the support rods are fixedly connected with the inner walls of the slotted ducts;
the yaw module comprises at least three yaw units which are uniformly arranged between the connecting ring and the slotted duct;
the yaw unit comprises a yaw rotating shaft, a yaw control surface and a yaw steering engine, wherein one end of the yaw rotating shaft is fixedly connected with the connecting ring, and the other end of the yaw rotating shaft is fixedly connected with the inner wall of the slotted duct; the yaw control surface is arranged on the yaw rotating shaft and can rotate freely around the yaw rotating shaft; the yaw steering engine is arranged on the yaw rotating shaft and used for adjusting the angle of the yaw control surface on the yaw rotating shaft;
the plume rotor comprises a hub and at least three fan blades;
the lower end of the rotating shaft of the paddle hub is fixedly connected with the connecting ring;
the fan blade comprises a blade root, a blade tip, a front edge and a rear edge, wherein the blade root is fixedly connected with the blade hub, the blade tip stretches into a notch of the slotted duct, a cross flow fan is arranged on the front edge, a variable-pitch control surface is arranged on the rear edge, and a motor for driving the cross flow fan is arranged on the blade root;
the cross flow fan is used for generating low-pressure vortex inside when rotating at a high speed, generating larger pressure difference on the upper surface and the lower surface of the front edge of the blade, and generating thrust by exhausting airflow to the rear edge, so that the corresponding fan blade can realize autorotation under the driving of no additional power.
As a further optimization scheme of the slotted duct type plume rotor craft, the slotted duct type plume rotor craft further comprises a telescopic manipulator, wherein the telescopic manipulator is arranged at the lower end of the connecting ring and is used for grabbing and loading.
As a further optimization scheme of the slotted ducted type plume rotorcraft, the slotted ducted type plume rotorcraft further comprises a landing gear, and the landing gear is arranged at the lower end of the connecting ring.
As a further optimization scheme of the slotted ducted type plume rotor craft, the number of the supporting rods is three.
As a further optimization scheme of the slotted ducted rotor craft, the number of the yaw units is three.
Compared with the prior art, the invention has the following technical effects:
1. compared with the common rotor wing, the wing type of the rotor wing with the rolling flow hardly stalls, so that the limit of a stall attack angle is avoided, and the aerodynamic efficiency is higher. The winding rotor wing rotates automatically, no reactive torque is generated, and no guide vane is needed to be added in the duct body to balance the reactive torque, so that the structure is simpler, and the weight is reduced to a great extent. Therefore, with the same power, greater lift can be obtained using the rotor.
2. On the premise of considering the flapping motion of the blade, a mode of slotting on the inner wall of the duct is adopted. Compared with a common ungrooved duct, the inner wall grooved duct can effectively inhibit the generation of tip vortex with energy loss and lift loss, improve rotor efficiency, and increase the radius of the blade, so that larger lift force is provided.
Drawings
FIG. 1 is an overall layout of a slotted ducted rotor aircraft of the present invention;
FIG. 2 is a schematic structural view of a slotted ducted roll-up rotorcraft of the present invention;
figure 3 is a schematic view of the structure of the rotor of the present invention;
figure 4 is a schematic cross-sectional view of a single fan blade of the plume rotor of the present invention;
FIG. 5 is a schematic view of the power plant of the present invention;
FIG. 6 is a schematic cross-sectional view of a slotted duct of the present invention.
In the figure, the rotor comprises a 1-slotted duct, a 2-rolling rotor, a 3-supporting beam, a 4-yaw control surface, a 5-telescopic manipulator, a 6-landing gear, a 7-hub, 8-fan blades, a 9-pitch control surface, a 10-cross flow fan, a 11-fan blade upper cross flow fan fixing surface and a 12-motor.
Detailed description of the preferred embodiments
The invention will be further described and illustrated with reference to the accompanying drawings.
As shown in fig. 1 and 2, the invention discloses a slotted duct type plume rotor craft, which comprises a slotted duct, a plume rotor, a supporting beam, a yaw module, a telescopic manipulator and a landing gear;
as shown in fig. 6, the slotted duct is provided with a groove on the inner wall of the duct for inhibiting the generation of blade tip vortex and reducing the loss of wing tips;
the support beam comprises a connecting ring and at least two support rods, wherein the connecting ring and the slotted duct are coaxially arranged; the support rods are uniformly arranged between the connecting rings and the slotted ducts, one ends of the support rods are fixedly connected with the connecting rings, and the other ends of the support rods are fixedly connected with the inner walls of the slotted ducts;
the yaw module comprises at least three yaw units which are uniformly arranged between the connecting ring and the slotted duct;
the yaw unit comprises a yaw rotating shaft, a yaw control surface and a yaw steering engine, wherein one end of the yaw rotating shaft is fixedly connected with the connecting ring, and the other end of the yaw rotating shaft is fixedly connected with the inner wall of the slotted duct; the yaw control surface is arranged on the yaw rotating shaft and can rotate freely around the yaw rotating shaft; the yaw steering engine is arranged on the yaw rotating shaft and used for adjusting the angle of the yaw control surface on the yaw rotating shaft;
the plume rotor comprises a hub and at least three fan blades;
the lower end of the rotating shaft of the paddle hub is fixedly connected with the connecting ring;
the fan blade comprises a blade root, a blade tip, a front edge and a rear edge, wherein the blade root is fixedly connected with the blade hub, the blade tip stretches into a notch of the slotted duct, a cross flow fan is arranged on the front edge, a variable-pitch control surface is arranged on the rear edge, and a motor for driving the cross flow fan is arranged on the blade root;
the cross flow fan is used for generating low-pressure vortex inside when rotating at a high speed, generating larger pressure difference on the upper surface and the lower surface of the front edge of the blade, and generating thrust by exhausting airflow to the rear edge, so that the corresponding fan blade can realize autorotation under the driving of no additional power;
the telescopic manipulator is arranged at the lower end of the connecting ring and used for grabbing and loading.
The landing gear is arranged at the lower end of the connecting ring.
The number of the supporting rods is three, and the number of the yaw units is three.
The following is a detailed description:
1. lift system
(1) Composition of lift system
As shown in fig. 3, the lift system of a slotted ducted rotor craft is mainly composed of two parts: the first part is a rolling rotor wing in the duct body and consists of three fan wing blades for providing most of lift force; the second portion is an external slotted duct for providing a small portion of auxiliary lift.
(2) Roll-flow rotor
As shown in fig. 3, 4 and 5, the rotor is composed of three rotating blades and vanes, and the motor is used to drive the cross-flow fan at the front edge of the vane wing profile to rotate at high speed, so that a large low-pressure vortex is generated in the cross-flow fan, a large pressure difference is generated on the upper and lower surfaces of the front edge of the wing profile, the blades and vanes can generate a large lifting force when rotating at low speed, and the air flow is discharged to the rear edge to generate thrust. Therefore, the whole rolling rotor can realize autorotation without extra power. The biggest difference between the rotary wing with the rolling flow and the common rotary wing is that the rotary wing is autorotative, and the countertorque is balanced without adopting related measures, so that a plurality of transmission devices are reduced, the structure is simpler, and the weight is reduced. It is more worth mentioning that the wing type of the fan does not stall almost, so that the limitation of the stall attack angle is avoided, and the aerodynamic efficiency is higher.
If a straight blade is used for the cross flow fan, the air flow may not be discharged after rotation, and vibration may be caused. If the inclined strip fan blades are adopted, the air flow can not enter the fan body at the same time after rotating, so that the blocking of the air flow can be avoided, and the vibration is reduced.
(3) Duct body structure
The tail end of the wing section is cut off by the slotted duct of the slotted duct type plume rotorcraft, and the groove is formed in the plane of the paddle disc, so that the paddle tip part of the plume rotorcraft is positioned in the duct, the wing tip loss can be effectively reduced, and the lift force is improved.
2. Supporting mechanism
The support structure inside the slotted duct type plume rotorcraft is three support rods, and a foldable undercarriage is arranged under the support cross beam. In the same horizontal plane, three yaw control surfaces are additionally arranged. The support structure is fixedly connected with the duct body structure.
3. Power plant
A motor is arranged at the root part of each fan blade of the slotted duct type plume rotorcraft, and the cross flow fan is directly driven to rotate.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
While the foregoing is directed to embodiments of the present invention, other and further details of the invention may be had by the present invention, it should be understood that the foregoing description is merely illustrative of the present invention and that no limitations are intended to the scope of the invention, except insofar as modifications, equivalents, improvements or modifications are within the spirit and principles of the invention.

Claims (3)

1. The slotted duct type plume rotor craft comprises a slotted duct, a plume rotor, a supporting beam, a telescopic manipulator, a landing gear and a yaw module;
the grooved duct is provided with a groove used for inhibiting the generation of blade tip vortex and reducing wing tip loss on the inner wall of the duct;
the support beam comprises a connecting ring and at least two support rods, wherein the connecting ring and the slotted duct are coaxially arranged; the support rods are uniformly arranged between the connecting rings and the slotted ducts, one ends of the support rods are fixedly connected with the connecting rings, and the other ends of the support rods are fixedly connected with the inner walls of the slotted ducts;
the yaw module comprises at least three yaw units which are uniformly arranged between the connecting ring and the slotted duct;
the yaw unit comprises a yaw rotating shaft, a yaw control surface and a yaw steering engine, wherein one end of the yaw rotating shaft is fixedly connected with the connecting ring, and the other end of the yaw rotating shaft is fixedly connected with the inner wall of the slotted duct; the yaw control surface is arranged on the yaw rotating shaft and can rotate freely around the yaw rotating shaft; the yaw steering engine is arranged on the yaw rotating shaft and used for adjusting the angle of the yaw control surface on the yaw rotating shaft;
the plume rotor comprises a hub and at least three fan blades;
the lower end of the rotating shaft of the paddle hub is fixedly connected with the connecting ring;
the fan blade comprises a blade root, a blade tip, a front edge and a rear edge, wherein the blade root is fixedly connected with the blade hub, the blade tip stretches into a notch of the slotted duct, a cross flow fan is arranged on the front edge, a variable-pitch control surface is arranged on the rear edge, and a motor for driving the cross flow fan is arranged on the blade root;
the cross flow fan is used for generating low-pressure vortex inside when rotating at a high speed, generating larger pressure difference on the upper surface and the lower surface of the front edge of the blade, and generating thrust by exhausting airflow to the rear edge, so that the corresponding fan blade can realize autorotation under the driving of no additional power;
the telescopic manipulator is arranged at the lower end of the connecting ring and used for grabbing and loading;
the landing gear is arranged at the lower end of the connecting ring.
2. The slotted ducted rotor craft of claim 1, wherein the number of support bars is three.
3. The slotted ducted rotor craft of claim 1, wherein the number of yaw units is three.
CN201711000170.XA 2017-10-24 2017-10-24 Slotted duct type rotor wing aircraft with rolling flow Active CN107672802B (en)

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CN107672802B true CN107672802B (en) 2023-10-27

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CN109018321A (en) * 2018-07-02 2018-12-18 寇冠 Driven rotor craft
CN109334970B (en) * 2018-11-13 2021-11-30 四川大学 Dual rotor ducted system
CN109334952A (en) * 2018-11-26 2019-02-15 南京航空航天大学 A kind of Novel paddle based on the driving of embedded shrouded propeller
CN111232191A (en) * 2018-11-29 2020-06-05 戴瑾 Rotor craft using control surface to control attitude
CN109515704B (en) * 2018-12-18 2024-04-16 南京航空航天大学 Ducted plume rotorcraft based on cycloidal propeller technology
US11286955B2 (en) * 2019-10-11 2022-03-29 General Electric Company Ducted fan with fan casing defining an over-rotor cavity
CN110963035A (en) * 2019-12-18 2020-04-07 王力丰 Personal aircraft with compressed air as power source and operation method thereof
CN111086624A (en) * 2020-01-20 2020-05-01 张世栋 Shroud-band type blade tip turbulence blocking device for ducted propeller
CN117836208A (en) * 2021-08-17 2024-04-05 挪威航空股份有限公司 Attitude control system for EVTOL aviation vehicle of multi-rotor crossflow fan type
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CN207450245U (en) * 2017-10-24 2018-06-05 南京航空航天大学 Fluting culvert type plume rotor craft

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