Aerodynamic performance of ducted propeller shaft of land-air vehicle with optional fixed structure

Abstract

This invention discloses a fixed-type aerodynamic performance-selective ducted propeller shaft structure for land-to-air aircraft. The fixed-type structure includes a central main shaft, at least one first rotor, at least one second rotor, at least one third rotor, a first duct corresponding to each of the first rotors, a second duct corresponding to each of the second rotors, and a third duct corresponding to each of the third rotors. The first rotors are fixedly mounted on the central main shaft. The first duct is fitted around the outer periphery of the first rotor. The second rotor is loosely fitted onto the central main shaft, and its second blade is fixedly connected to the second duct. The third rotor is fixedly connected between the central main shaft and the third duct. This fixed-type structure uses the duct and rotor as equivalent to a pump wheel, a turbine, and a guide wheel, respectively, thereby achieving different aerodynamic performances to meet different aerodynamic and lift requirements, thus enabling selection of aerodynamic performance.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, and more specifically to a selective aerodynamic performance-based fixed structure for a ducted propeller shaft of a land-to-air aircraft. Background Technology

[0002] Traditionally, small unmanned aerial vehicles (UAVs) have been widely used due to their low cost and simple structure. However, their use has also revealed many related problems. For example, when the effective lift generated by the ducted rotor system itself is insufficient to support the weight of all components, including the ducted rotor itself, the use of a ducted rotor configuration can actually be detrimental to improving the overall aerodynamic performance. Therefore, optimizing the aerodynamic performance of the ducted lift system is crucial in the design of ducted aircraft. Summary of the Invention

[0003] In view of this, the present invention provides a fixed structure for a ducted rotor shaft with selectable aerodynamic performance for land-to-air aircraft. This fixed structure uses three different connection schemes to construct the duct and rotor on the same central main shaft, which are equivalent to pump wheel, turbine and guide wheel respectively, thereby achieving different aerodynamic performance and meeting different aerodynamic and lift requirements, thus realizing the selection of aerodynamic performance.

[0004] The present invention adopts the following specific technical solution:

[0005] The ducted propeller shaft of the land-to-air vehicle can be selected by an aerodynamic performance-type fixed structure. The fixed structure includes a central main shaft, at least one first rotor, at least one second rotor, at least one third rotor, a first duct corresponding to the first rotor, a second duct corresponding to the second rotor, and a third duct corresponding to the third rotor.

[0006] The first rotor, the second rotor, and the third rotor are all distributed at intervals along the axial direction of the central main shaft, and are all coaxially arranged with the central main shaft;

[0007] Each of the first rotor blades is fixedly mounted on the central main shaft and is provided with a plurality of first blades distributed circumferentially; a corresponding first duct is sleeved on the outer circumferential side of the first blade, and there is a radial gap between the blade tip of the first blade and the inner circumferential surface of the first duct; when the central main shaft drives the first rotor blade to rotate, the first duct has a flow guiding function, and the central main shaft, the corresponding first rotor blade, and the first duct form a pump wheel to provide power;

[0008] Each second rotor is loosely fitted around the outer periphery of the central main shaft and is provided with multiple second blades distributed circumferentially; a corresponding second duct is fitted around the outer periphery of the second rotor; the tip of the second blade is fixedly connected to the inner circumferential surface of the corresponding second duct; the second duct is used to connect to the fuselage, and the fuselage drives the second duct and the second rotor to rotate to obtain power, and the corresponding second rotor and the second duct form a turbine;

[0009] Each of the third rotors is fixedly connected to the central main shaft and is provided with multiple third blades distributed circumferentially; a corresponding third duct is sleeved on the outer circumference of each third rotor; the tip of the third blade is fixedly connected to the inner circumferential surface of the corresponding third duct; the central main shaft and the corresponding third rotor and the third duct form a guide wheel.

[0010] Furthermore, the first duct, the second duct, and the third duct are ducts for small oil-powered aircraft or coaxial twin-rotor aircraft.

[0011] Furthermore, the first rotor, the second rotor, and the third rotor are all provided with a central mounting hole;

[0012] Both the first rotor and the third rotor are fixedly connected to the central main shaft through the central mounting hole using a column hole mounting structure.

[0013] Furthermore, the first blade, the second blade, and the third blade are all evenly distributed circumferentially.

[0014] Furthermore, the first rotor, the second rotor, and the third rotor are arranged sequentially along the axial direction of the central main shaft.

[0015] Furthermore, there is one first rotor and one second rotor, and two third rotors are provided, with the first rotor and the second rotor distributed between the two third rotors.

[0016] Beneficial effects:

[0017] The selective aerodynamic performance fixed structure of the ducted propeller shaft of the land-to-air vehicle of the present invention forms three different connection structures by using multiple rotors sharing a central main shaft and ducts corresponding to each rotor. The three connection structures correspond to aerodynamic equivalent wheels with different efficiencies, which can be approximately equivalent to pump wheels, turbines, and guide wheels, respectively. By arbitrarily combining the number and types of the above three connection structures, a variety of different schemes can be constructed on the central main shaft, thereby achieving different aerodynamic efficiencies as a whole, which can meet different aerodynamic and lift requirements, thus enabling the selection of aerodynamic performance and improving the overall aerodynamic efficiency of the land-to-air vehicle. Therefore, this fixed structure can achieve different aerodynamic efficiencies, meet different aerodynamic and lift requirements, and achieve the selection of aerodynamic performance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a structurally optional aerodynamic performance-based rigid connection structure for the ducted propeller shaft of the land-to-air aircraft of the present invention.

[0019] Figure 2 This is a schematic diagram of another structural design of the optional aerodynamic performance-based fixed connection structure for the ducted propeller shaft of the land-to-air aircraft of the present invention.

[0020] Wherein, 1-central main shaft, 2-first rotor, 3-second rotor, 4-third rotor, 5-first duct, 6-second duct, 7-third duct Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] Example 1

[0023] This invention provides a selective aerodynamic performance-based fixed structure for ducted propeller shafts in land-to-air aircraft, such as... Figure 1 As shown in the structure, the fixed connection structure includes a central main shaft 1, a first rotor 2, a second rotor 3, a third rotor 4, a first duct 5 corresponding to the first rotor 2, a second duct 6 corresponding to the second rotor 3, and a third duct 7 corresponding to the third rotor 4. In this embodiment, an optional aerodynamic performance fixed connection structure for a land-air vehicle ducted propeller shaft with one first rotor 2, one second rotor 3, one third rotor 4, one first duct 5, one second duct 6, and one third duct 7 is used as an example for explanation. The first rotor 2, the second rotor 3, and the third rotor 4 are all distributed at intervals along the axial direction of the central main shaft 1 and are all coaxially arranged with the central main shaft 1. The first rotor 2, the second rotor 3, and the third rotor 4 are arranged sequentially along the axial direction of the central main shaft 1.

[0024] The first rotor 2 is fixedly mounted on the central main shaft 1 and is provided with four first blades distributed circumferentially. The four first blades are evenly distributed circumferentially. A corresponding first duct 5 is sleeved on the outer circumference of the first blades. The first duct 5 is coaxially arranged with the first rotor 2, and there is a radial gap between the blade tip and the inner circumferential surface of the first duct 5, so that the first rotor 2 can rotate relative to the first duct 5. When the central main shaft 1 drives the first rotor 2 to rotate, the first duct 5 has a flow guiding function. The central main shaft 1, the corresponding first rotor 2, and the first duct 5 form a pump wheel to provide power.

[0025] The second rotor 3 is loosely fitted around the outer periphery of the central main shaft 1, allowing relative rotation between the second rotor 3 and the central main shaft 1. The second rotor 3 is provided with four second blades distributed circumferentially. The four second blades are evenly distributed circumferentially. A corresponding second duct 6 is fitted around the outer periphery of the second rotor 3. The second duct 6, the second rotor 3, and the central main shaft 1 are coaxially arranged. The tips of the second blades are fixedly connected to the inner circumferential surface of the corresponding second duct 6, allowing the second rotor 3 and the second duct 6 to rotate together. The second duct 6 is used to connect to the fuselage. The fuselage drives the second duct 6 and the second rotor 3 to rotate to obtain power. The corresponding second rotor 3 and the second duct 6 form a turbine.

[0026] Each third rotor 4 is fixedly connected to the central main shaft 1 and is provided with four third blades distributed circumferentially; the four third blades are evenly distributed circumferentially; a corresponding third duct 7 is fitted on the outer circumference of each third rotor 4; the tip of the third blade is fixedly connected to the inner circumferential surface of the corresponding third duct 7, so that the third rotor 4, the central main shaft 1 and the third duct 7 are coaxially arranged and rotate together; the central main shaft 1 and the corresponding third rotor 4 and third duct 7 form a guide wheel.

[0027] In the above-mentioned optional aerodynamic performance fixed structure of the ducted propeller shaft of the land and air aircraft, the first duct 5, the second duct 6 and the third duct 7 adopt the ducts of small oil-powered aircraft or coaxial twin-rotor aircraft.

[0028] In order to enable the first rotor 2, the second rotor 3 and the third rotor 4 to be installed on the central spindle 1, the first rotor 2, the second rotor 3 and the third rotor 4 are all provided with central mounting holes; the first rotor 2 and the third rotor 4 are fixedly connected to the central spindle 1 through the central mounting holes using a column hole mounting structure; the central spindle 1 can pass through the central mounting hole of the second rotor 3.

[0029] When the above structure is adopted, with the central main shaft 1 driven by the motor, the first rotor 2 outputs the main lift, the second duct 6 and the second rotor 3 can assist in constructing the flow field, and the third rotor 4 can further improve the lift of the system, thereby reducing the requirements of the motor for the whole machine. At the same time, the ducts in the above structure can provide a certain protective function for the rotor, and the structure is lightweight and easy to install. Different installation positions of the above three connection structures can achieve different aerodynamic effects, so as to achieve the selection of aerodynamic effects.

[0030] Example 2

[0031] This invention provides a selective aerodynamic performance-based fixed structure for ducted propeller shafts in land-to-air aircraft, such as... Figure 2 As shown in the structure, the fixed structure includes a central main shaft 1, a first rotor 2, a second rotor 3, two third rotors 4, a first duct 5 corresponding to the first rotor 2, a second duct 6 corresponding to the second rotor 3, and two third ducts 7 corresponding one-to-one with the two third rotors 4; the first rotor 2 and the second rotor 3 are distributed between the two third rotors 4; the first rotor 2, the second rotor 3, and the third rotor 4 are all distributed at intervals along the axial direction of the central main shaft 1, and are all coaxially arranged with the central main shaft 1; the third rotor 4, the first rotor 2, the second rotor 3, and the third rotor 4 are arranged sequentially along the axial direction of the central main shaft 1;

[0032] The first rotor 2 is fixedly mounted on the central main shaft 1 and is provided with four first blades distributed circumferentially. The four first blades are evenly distributed circumferentially. A corresponding first duct 5 is sleeved on the outer circumference of the first blade. The first duct 5 is coaxially arranged with the first rotor 2, and there is a radial gap between the blade tip and the inner circumferential surface of the first duct 5, so that the first rotor 2 can rotate relative to the first duct 5. When the central main shaft 1 drives the first rotor 2 to rotate, the first duct 5 has a flow guiding function. The central main shaft 1 and the corresponding first rotor 2 and first duct 5 form a pump wheel to provide power.

[0033] The second rotor 3 is loosely fitted around the outer periphery of the central main shaft 1, allowing relative rotation between the second rotor 3 and the central main shaft 1. The second rotor 3 is provided with four second blades distributed circumferentially. The four second blades are evenly distributed circumferentially. A corresponding second duct 6 is fitted around the outer periphery of the second rotor 3. The second duct 6, the second rotor 3, and the central main shaft 1 are coaxially arranged. The tips of the second blades are fixedly connected to the inner circumferential surface of the corresponding second duct 6, allowing the second rotor 3 and the second duct 6 to rotate together. The second duct 6 is used to connect to the fuselage. The fuselage drives the second duct 6 and the second rotor 3 to rotate to obtain power. The corresponding second rotor 3 and the second duct 6 form a turbine.

[0034] Both third rotors 4 are fixedly connected to the central main shaft 1, and each is provided with four third blades distributed circumferentially. The four third blades are evenly distributed circumferentially. A corresponding third duct 7 is fitted on the outer circumference of each third rotor 4. The tip of the third blade is fixedly connected to the inner circumferential surface of the corresponding third duct 7, so that the third rotor 4, the central main shaft 1 and the third duct 7 are coaxially arranged and rotate together. The central main shaft 1 and the corresponding third rotor 4 and third duct 7 form a guide wheel.

[0035] In the above-mentioned optional aerodynamic performance fixed structure of the ducted propeller shaft of the land and air aircraft, the first duct 5, the second duct 6 and the third duct 7 adopt the ducts of small oil-powered aircraft or coaxial twin-rotor aircraft.

[0036] In order to enable the first rotor 2, the second rotor 3 and the third rotor 4 to be installed on the central spindle 1, the first rotor 2, the second rotor 3 and the third rotor 4 are all provided with central mounting holes; the first rotor 2 and the third rotor 4 are fixedly connected to the central spindle 1 through the central mounting holes using a column hole mounting structure; the central spindle 1 can pass through the central mounting hole of the second rotor 3.

[0037] The coaxial multirotor system employing the aforementioned ducted rotor shaft-mounted, aerodynamically selective, rigid structure for land-to-air aircraft can fully utilize the shared aerodynamic performance of the ducted rotors. Furthermore, the flow fields of each rotor can be coupled and interconnected, a feature not found in standalone ducted rotor installations. This results in a wider range of overall lift output, allowing for free control of lift output rather than a constant value. Figure 2 The aerodynamic performance can be diversified by simply using different installation methods. The processing requirements for the duct configuration are low, which reduces the manufacturing difficulty and usage cost.

[0038] The aforementioned ducted rotor shaft of the land-to-air vehicle can be configured with an aerodynamic performance-based fixed structure. This structure comprises multiple rotors sharing a central main shaft 1 and corresponding ducts, forming three different connection structures. These three connection structures correspond to aerodynamically equivalent wheels with varying efficiencies, and can be approximated as a pump wheel, turbine, and guide wheel, respectively. By arbitrarily combining the number and type of these three connection structures, various schemes can be constructed on the central main shaft 1, thereby achieving different overall aerodynamic performances. This satisfies different aerodynamic and lift requirements, enabling the selection of aerodynamic performance and improving the overall aerodynamic efficiency of the land-to-air vehicle. Therefore, this fixed structure can achieve different aerodynamic performances, meet different aerodynamic and lift requirements, and allow for the selection of aerodynamic performance.

[0039] It should be noted that Embodiment 1 and Embodiment 2 are merely two specific examples of the present invention. In actual use, the number and position of rotors and corresponding ducts on the central main shaft can be configured according to actual needs, thereby constructing aerodynamic systems with different aerodynamic effects.

[0040] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A ducted propeller shaft of a land-aircraft with alternative aerodynamic performance of the fixed structure, characterized by, The center main shaft, at least one first rotor, at least one second rotor, at least one third rotor, a first duct corresponding to the first rotor, a second duct corresponding to the second rotor, and a third duct corresponding to the third rotor are included. The first rotor, the second rotor, and the third rotor are spaced along the axial direction of the center main shaft and are coaxially arranged with the center main shaft. Each first rotor is fixedly installed on the center main shaft and is provided with a plurality of first blades distributed in the circumferential direction. A corresponding first duct is sleeved on the outer circumferential side of the first blade, and a radial gap is formed between the blade tip of the first blade and the inner circumferential surface of the first duct. When the center main shaft drives the first rotor to rotate, the first duct has a flow guiding function, and the center main shaft, the corresponding first rotor, and the first duct form a pump wheel to provide power. Each second rotor is sleeved on the outer circumferential side of the center main shaft and is provided with a plurality of second blades distributed in the circumferential direction. A corresponding second duct is sleeved on the outer circumferential side of the second rotor. The blade tip of the second blade is fixedly connected to the inner circumferential surface of the corresponding second duct. The second duct is used to be connected to the body, and the second duct and the second rotor are driven to rotate by the body to obtain power. The corresponding second rotor and the second duct form a turbine. Each third rotor is fixedly connected to the center main shaft and is provided with a plurality of third blades distributed in the circumferential direction. A corresponding third duct is sleeved on the outer circumferential side of each third rotor. The blade tip of the third blade is fixedly connected to the inner circumferential surface of the corresponding third duct. The center main shaft, the corresponding third rotor, and the third duct form a guide wheel.

2. The securement structure of claim 1, wherein The first duct, the second duct, and the third duct adopt the ducts of a small oil-powered aircraft or a coaxial dual-rotor aircraft.

3. The securement structure of claim 1, wherein The first rotor, the second rotor, and the third rotor are provided with a center mounting hole. The first rotor and the third rotor are fixedly connected to the center main shaft through the center mounting hole in a post hole mounting mode.

4. The securement structure of claim 1, wherein The first blades, the second blades, and the third blades are uniformly distributed in the circumferential direction.

5. The securement structure of any of claims 1-4, wherein, The first rotor, the second rotor, and the third rotor are arranged in sequence along the axial direction of the center main shaft.

6. The securement structure of any of claims 1-4, wherein The first rotor and the second rotor are each provided with one, the third rotor is provided with two, and the first rotor and the second rotor are distributed between the two third rotors.

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