Multi-rotor hydrogen energy unmanned aerial vehicle

Abstract

The invention discloses a multi-rotor hydrogen energy unmanned aerial vehicle which comprises an unmanned aerial vehicle body, a gaseous hydrogen storage bottle, a plurality of arm spans and a plurality of propeller pile fusion type structures. The gaseous hydrogen storage bottle is arranged on the unmanned aerial vehicle body, and the plurality of arm spans are uniformly arranged on the side surface of the unmanned aerial vehicle body; the propeller pile fusion type structure is arranged at the end, away from the unmanned aerial vehicle body, of the arm extension, and the propeller pile fusion type structure and the arm extension are arranged in a matched mode. According to the structure, the air-cooled reactor is arranged below the blades of the unmanned aerial vehicle to form a propeller-reactor fused structure, high-speed airflow generated by the propeller blade thruster is directly used for air inlet reaction and cooling of the air-cooled reactor, and the heat dissipation performance of a battery loaded on the unmanned aerial vehicle can be greatly improved on the basis that the structure of the unmanned aerial vehicle is not changed; and the requirements of actual use are well met.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a multi-rotor hydrogen energy unmanned aerial vehicle (UAV). Background Art

[0002] With the rapid development of the low-altitude economy in various industries, UAVs have been widely used in their fields. Multi-rotor UAVs have multiple significant characteristics in structural design. They are made of high-strength lightweight materials (such as lightweight carbon fiber), which not only ensure the firmness of the airframe but also effectively reduce the overall weight of the UAV, thereby improving the load capacity of the UAV. At the same time, due to its system composition and power characteristics, the flight characteristics of multi-rotor UAVs are different from those of fixed-wing and helicopter UAVs, and they have characteristics such as flexible response, stable hovering, and vertical takeoff and landing.

[0003] Currently, most industrial multi-rotor UAVs on the market use lithium-ion batteries and fossil fuels as power sources. UAVs powered by lithium batteries perform poorly in terms of endurance, recharging ability, and performance in low-temperature environments, which has become a pain point in the UAV industry. In addition, multi-rotor UAVs powered by fossil fuels face great challenges in terms of fuel economy and environmental protection. UAVs equipped with lithium battery power sources still occupy the mainstream position in the market. The advantage of lithium battery UAVs is that the UAV system layout is simple, suitable for small aircraft models and short-distance airworthiness, and has high cost performance; however, in the face of large-load and long-endurance usage scenarios, lithium battery multi-rotor UAVs seem inadequate.

[0004] Hydrogen-powered UAVs use air-cooled fuel cells as power sources. Currently, most of the technical solutions adopted by hydrogen-powered multi-rotor UAVs on the market are cathode-open air-cooled stacks. Considering the parasitic power consumption of the UAV's own load and air compressors, it is impractical to use a closed fuel cell stack on the UAV. In addition, most hydrogen-powered UAVs arrange the stack below the main body of the UAV fuselage (usually made into a shell integrating the fuel cell control system), and this layout method usually compresses the ability of the UAV to carry mission loads. Summary of the Invention

[0005] Embodiments of the present invention provide a multi-rotor hydrogen energy UAV, aiming to solve problems such as poor performance of existing UAVs at low temperatures, short endurance under large loads, low load-carrying capacity, and the need for independent configuration of fans to meet the air required for the heat dissipation and reaction of the stack.

[0006] To solve the above technical problems, an embodiment of the present invention provides a multi-rotor hydrogen energy unmanned aerial vehicle, which includes an unmanned aerial vehicle body, a gaseous hydrogen storage cylinder, several arm spans, and several propeller-pile integrated structures; the gaseous hydrogen storage cylinder is arranged on the unmanned aerial vehicle body, and several of the arm spans are evenly arranged on the side surface of the unmanned aerial vehicle body; the propeller-pile integrated structure is arranged at one end of the arm span away from the unmanned aerial vehicle body, and the propeller-pile integrated structure is arranged to be adapted to the arm span.

[0007] As a preferred embodiment, several of the propeller-pile integrated structures are arranged at intervals, and the propeller-pile integrated structures are arranged in one-to-one correspondence with the arm spans. That is, on the premise of satisfying the arrangement of the propeller-pile integrated structures at intervals, one propeller-pile integrated structure is arranged to be adapted to one arm span.

[0008] As a preferred embodiment, each of the propeller-pile integrated structures includes an air-cooled stack, a first hydrogen pipeline, a second hydrogen pipeline, a propeller blade, and a brushless motor; the brushless motor is arranged at the end of the arm span; the propeller blade is arranged on the brushless motor; the air-cooled stack is suspended on the arm span, and the air-cooled stack is obliquely arranged below the brushless motor; one end of the first hydrogen pipeline is connected to the air-cooled stack through a hydrogen intake main port, and the other end is connected to the second hydrogen pipeline; the second hydrogen pipeline is connected to the gaseous hydrogen storage cylinder.

[0009] As a preferred embodiment, the air-cooled stack is connected to the arm span through a hanging bracket; the hanging bracket is a hollow "X"-shaped bracket.

[0010] As a preferred embodiment, the arm span is a hollow arm span, and the arm span is connected and communicated with the "X"-shaped bracket.

[0011] As a preferred embodiment, the first hydrogen pipeline is accommodated in the "X"-shaped bracket; the second hydrogen pipeline is arranged in the arm span.

[0012] As a preferred embodiment, a wind guide cover is arranged on the air-cooled stack, and the wind guide cover extends from one long side of the air-cooled stack to the other long side; and the cover opening of the wind guide cover is arranged opposite to the brushless motor.

[0013] As a preferred embodiment, the propeller blade is a single propeller blade (helical propeller blade); the total rated output power of the air-cooled stack ≥ 10kW; the air-cooled stack is an air-cooled stack using a thin graphite bipolar plate; the performance parameters of the air-cooled stack are 0.51V@0.9A / cm 2 , active area 250cm 2 .

[0014] As a preferred embodiment, a mission payload is provided on one side of the UAV body away from the gaseous hydrogen storage cylinder; the mission payload is mounted on the UAV body.

[0015] As a preferred embodiment, at least two gaseous hydrogen storage cylinders are provided, and the two gaseous hydrogen storage cylinders are arranged in parallel.

[0016] As a preferred embodiment, eight arm spans are provided, and the eight arm spans are evenly arranged on the side of the UAV body to form a cross-octocopter hydrogen energy UAV body; the maximum wheelbase of the octocopter hydrogen energy UAV body is 2250 mm. The octocopter layout scheme can effectively balance the take-off weight, and the cross-octocopter rotor layout scheme can provide a stronger load capacity for heavy-load multi-rotor UAVs.

[0017] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects: In the structure of this application, an air-cooled stack (i.e., a fuel cell stack system) is arranged below the propeller blades of the UAV, forming a structure integrating the propeller and the stack. The high-speed airflow generated by the propeller blade thruster is directly used for the intake reaction and cooling of the air-cooled stack. The structure of this application can make full use of the airflow generated by the propeller blades of the multi-rotor UAV. On the one hand, the propeller blades of the UAV directly blow the stack to provide sufficient heat dissipation capacity for it. On the other hand, the high-speed airflow can overcome the resistance of the stack system and provide sufficient air for the air-cooled stack reaction. The structure of this application can also make full use of the rotor layout and fuselage structure of the multi-rotor UAV: on the one hand, the electrical and system pipelines are arranged inside the arm span of the UAV, thereby optimizing the pipeline layout inside the UAV and providing a supporting pipeline connection scheme for the structure design of the integrated propeller and stack; on the other hand, the air-cooled stack is arranged under the UAV propeller blades to prevent the stack system from occupying the space below the compressor body, reducing the ability of the UAV to carry the mission payload. At the same time, the various rotor arrangement schemes of the multi-rotor UAV provide a feasible technical solution for adding multiple stacks. The structure of this application is simple, easy to disassemble and assemble, convenient for maintenance, has good stability, is economical, safe and practical, and can greatly improve the heat dissipation performance of the battery loaded by the UAV without changing the structure of the UAV, well meeting the actual use requirements. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0019] Figure 1 It is a schematic diagram of the overall structure of a multi-rotor hydrogen energy UAV according to an embodiment of the present invention;

[0020] Figure 2 is Figure 1 a schematic structural diagram of the propeller-stack fusion structure;

[0021] Figure 3 It shows Figure 2 the velocity field (A) of an octocopter drone designed with the propeller-stack fusion structure and the distribution diagram of the fluid vectors (B) near the propeller stack;

[0022] Figure 4 It shows Figure 2 the vorticity (A) and velocity (B) distribution diagrams near the rotor of an octocopter drone designed with the propeller-stack fusion structure.

[0023] The realization, functional features and advantages of the object of the present invention will be further described with reference to the embodiments and the accompanying drawings. Specific Embodiments

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of the technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0026] At present, the power sources of drones mostly rely on lithium-ion batteries and fossil fuels, and there are few hydrogen-powered drone products in long-endurance, heavy-load and low-temperature application scenarios. Existing hydrogen-powered drones usually arrange the fuel cell stack and its system structure at the mounting location of the mission payload. This layout method will reduce the payload carrying capacity of the drone. Moreover, most of the fuel cell systems carried by existing hydrogen-powered drones are open-type air-cooled stacks, and fans need to be independently configured to meet the air required for the heat dissipation and reaction of the stack, and there are also few mentions of the relevant layout schemes for the electrical system and pipelines.

[0027] The structure of this application is a novel structural design that directly uses the high-speed airflow generated by the propeller blade thruster for the intake reaction and cooling of the fuel cell, and combines the number of rotors of the drone and the output power requirement of the drone power system to reasonably configure the propeller-stack fusion structure (for example, two of the four rotors adopt the propeller-stack fusion design or all four rotors adopt it) and the electrical pipeline layout. Among them:

[0028] (1) Rotor blade matching and selection: Output the fuel cell power according to the application scenario and requirements, obtain information such as the heat generation of the fuel cell from the output power of the stack as the basis for blade selection and matching, and design or match the rotor blades of the UAV based on the heat generation of the fuel cell, load design, and the overall weight of the UAV.

[0029] (2) Layout of the integrated structure of the stack and blades: Determine the number of integrated stack and blade structures designed according to the output power of the stack mentioned in the requirements, and finally determine the relevant design parameters such as the wingspan and wheelbase of the UAV.

[0030] (3) Numerical simulation to verify the rationality of the integrated structure of the stack and blades: Obtain whether the intake performance of the fuel cell and the aerodynamic performance of the blades are affected under the integrated structure design of the stack and blades through numerical simulation and other means, and finally output the design scheme of the multi-rotor hydrogen energy UAV under the integrated structure design of the stack and blades.

[0031] Specifically, as Figures 1 to 2 shown, an embodiment of the present invention provides a multi-rotor hydrogen energy UAV, including a UAV body 10, a gaseous hydrogen storage cylinder 20, several wingspans 30, and several integrated stack and blade structures 40; the gaseous hydrogen storage cylinder 20 is arranged on the UAV body 10, and several wingspans 30 are evenly arranged on the side of the UAV body 10; the integrated stack and blade structure 40 is arranged at one end of the wingspan 30 far from the UAV body 10, and the integrated stack and blade structure 40 is arranged in adaptation with the wingspan 30.

[0032] As a preferred implementation manner, several integrated stack and blade structures 40 are arranged at intervals, and the integrated stack and blade structures 40 are arranged in one-to-one correspondence with the wingspans 30. That is, on the premise of satisfying the arrangement of the integrated stack and blade structures 40 at intervals, one integrated stack and blade structure 40 is arranged in adaptation with one wingspan 30.

[0033] As a preferred implementation manner, each integrated stack and blade structure 40 includes an air-cooled stack 41, a first hydrogen pipeline 42, a second hydrogen pipeline 43, a blade 44, and a brushless motor 45; the brushless motor 45 is arranged at the end of the wingspan 30; the blade 44 is arranged on the brushless motor 45; the air-cooled stack 41 is hung on the wingspan 30, and the air-cooled stack 41 is obliquely placed below the brushless motor 45; one end of the first hydrogen pipeline 42 is connected to the air-cooled stack 41 through a hydrogen intake main port 46, and the other end is connected to the second hydrogen pipeline 43; the second hydrogen pipeline 43 is connected to the gaseous hydrogen storage cylinder 20.

[0034] As a preferred implementation manner, the air-cooled stack 41 is connected to the wingspan 30 through a hanging bracket 50; the hanging bracket 50 is a hollow "X"-shaped bracket.

[0035] As a preferred embodiment, the armspan 30 is a hollow armspan, and the armspan 30 is communicatively connected to the "X"-shaped bracket.

[0036] As a preferred embodiment, the first hydrogen pipeline 42 is accommodated within the "X"-shaped bracket; the second hydrogen pipeline 43 is disposed within the armspan 30.

[0037] As a preferred embodiment, a wind guide cover 47 is provided on the air-cooled stack 41, and the wind guide cover 47 extends from one long side of the air-cooled stack 41 to the other long side; and the opening of the wind guide cover 47 is oppositely disposed with respect to the brushless motor 45. In this way, through the wind guide cover 47, the air-cooled stack 41 can better collect the air provided by the blade 44.

[0038] As a preferred embodiment, the blade 44 is a single blade (propeller blade); the total output rated power of the air-cooled stack 41 ≥ 10 kW; the air-cooled stack 41 is an air-cooled stack using a thin graphite bipolar plate; the performance parameters of the air-cooled stack 41 are 0.51 V @ 0.9 A / cm 2 with an active area of 250 cm 2 .

[0039] Since the edge of the blade can supply the air required for the reaction of the air-cooled stack with greater wind force and wind pressure and meet the cooling and heat dissipation requirements, therefore, a single blade is adopted under the armspan for mounting the air-cooled stack (in this embodiment, there are four armspans for mounting the air-cooled stack), which can provide stronger power for the unmanned aerial vehicle and provide a stable operating environment for the air-cooled stack. The first hydrogen pipeline and the second hydrogen pipeline provide the hydrogen required for the reaction to the air-cooled stack through the total hydrogen inlet. When the unmanned aerial vehicle is operating, the brushless motor drives the blade to rotate, and a high-speed air flow is generated under the blade. The high-speed air flow collected by the wind guide cover is used to provide the air required for heat dissipation and reaction to the air-cooled stack.

[0040] For example, the multi-rotor unmanned aerial vehicle adopting the present application meets the application requirements of agricultural plant protection scenarios, and the output rated power of the fuel cell stack designed for heavy load application scenarios ≥ 10 kW. According to the performance of the air-cooled stack, a single-stack performance not exceeding 3 kW can better balance the service life and output performance of the unmanned aerial vehicle. Therefore, the whole machine adopts 4 air-cooled fuel cell stacks with a rated power of 2.5 kW, with a total rated power of 10 kW; the fuel cell stack in the fuel cell system adopts a thin graphite bipolar plate, and the performance parameters of the fuel cell stack are 0.51 V @ 0.9 A / cm 2 with an active area of 250 cm 2 , and the heat generation amount and the required heat dissipation amount of a single air-cooled stack can be obtained through numerical simulation or theoretical calculation, and the rotor can be designed or matched according to the volume of the fuel cell stack and the required heat dissipation amount.

[0041] As a preferred embodiment, a mission payload 60 is provided on a side of the UAV body 10 away from the gaseous hydrogen storage cylinder 20; the mission payload 60 is mounted on the UAV body 10.

[0042] As a preferred embodiment, at least two gaseous hydrogen storage cylinders 20 are provided, and the two gaseous hydrogen storage cylinders 20 are arranged in parallel.

[0043] As a preferred embodiment, eight booms 30 are provided, and the eight booms 30 are evenly arranged on the side of the UAV body 10 to form a cross-octocopter hydrogen energy UAV body; the maximum wheelbase of the octocopter hydrogen energy UAV body is 2250 mm. The use of the octocopter layout scheme can effectively balance the takeoff weight, and the use of the cross-octocopter rotor layout scheme can provide a more powerful load capacity for heavy-duty multi-rotor UAVs.

[0044] From Figure 3 the simulation results, when the UAV of the structure of the present application is in simulated hover, the high-speed airflow under the propellers can well overcome the resistance of the fuel cell system, and after being collected by the air guide cover, it passes through the fuel cell to provide the gas required for heat dissipation and reaction of the fuel cell; in addition, the highest gas flow velocity under the propeller blades reaches 4.85 m / s, and after passing through the fuel cell, the velocity drops to 3.94 m / s, with a small velocity loss. The airflow velocity under the booms where no fuel cell is arranged will not be affected, and the UAV can still obtain sufficient lift, so the overall design is reasonable.

[0045] Figure 4 Mainly verify the aerodynamic characteristics of the rotor. From Figure 4 the test results, the use of the propeller-fuel cell integrated structure is reasonable in terms of vorticity distribution and velocity distribution, and the design of the propeller-fuel cell integrated structure will not have a harmful reaction effect on the aerodynamic characteristics of the propeller blades, ensuring the flight stability of the UAV.

[0046] The structure of this application forms a structure integrating the propeller and the stack by arranging an air-cooled stack (i.e., a fuel cell stack system) below the propeller blades of the unmanned aerial vehicle. The high-speed airflow generated by the propeller blade thruster is directly used for the intake reaction and cooling of the air-cooled stack. The structure of this application can make full use of the airflow generated by the multi-rotor unmanned aerial vehicle's propeller blades. On the one hand, the propeller blades of the unmanned aerial vehicle directly blow the stack to provide sufficient heat dissipation capacity for it. On the other hand, the high-speed airflow can overcome the resistance of the stack system and provide sufficient air for the air-cooled stack reaction. The structure of this application can also make full use of the rotor layout and fuselage structure of the multi-rotor unmanned aerial vehicle: on the one hand, the electrical and system pipelines are arranged inside the armspan of the unmanned aerial vehicle, thereby optimizing the pipeline layout inside the unmanned aerial vehicle and providing a supporting pipeline connection scheme for the structure design of the propeller-stack integration; on the other hand, the air-cooled stack is arranged under the propeller blades of the unmanned aerial vehicle to prevent the stack system from occupying the space below the fuselage, reducing the ability of the unmanned aerial vehicle to carry mission payloads. At the same time, the various rotor arrangement schemes of the multi-rotor unmanned aerial vehicle provide a feasible technical solution for adding multiple stacks. The structure of this application is simple, easy to disassemble and assemble, convenient for maintenance, has good stability, is economically safe and practical, and can greatly improve the heat dissipation performance of the battery loaded by the unmanned aerial vehicle without changing the structure of the unmanned aerial vehicle, well meeting the actual use needs.

[0047] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-rotor hydrogen energy drone, characterized in that, It includes a UAV body, a gaseous hydrogen storage cylinder, several arm spans and several paddle-stack integrated structures; the gaseous hydrogen storage cylinder is arranged on the UAV body, and several of the arm spans are evenly arranged on the side of the UAV body; the paddle-stack integrated structure is arranged at one end of the arm span far from the UAV body, and the paddle-stack integrated structure is arranged in adaptation with the arm span.

2. The multi-rotor hydrogen energy unmanned aerial vehicle according to claim 1, wherein Several of the paddle-stack integrated structures are arranged alternately, and the paddle-stack integrated structures are arranged in one-to-one correspondence with the arm spans.

3. The multi-rotor hydrogen energy drone according to claim 1, wherein, Each of the paddle-stack integrated structures includes an air-cooled stack, a first hydrogen pipeline, a second hydrogen pipeline, a paddle and a brushless motor; the brushless motor is arranged at the end of the arm span; the paddle is arranged on the brushless motor; the air-cooled stack is suspended on the arm span, and the air-cooled stack is obliquely placed below the brushless motor; one end of the first hydrogen pipeline is connected to the air-cooled stack through a hydrogen intake main port, and the other end is connected to the second hydrogen pipeline; the second hydrogen pipeline is connected to the gaseous hydrogen storage cylinder.

4. The multi-rotor hydrogen energy unmanned aerial vehicle according to claim 3, characterized in that, The air-cooled stack is connected to the arm span through a suspension bracket; the suspension bracket is a hollow "X"-shaped bracket.

5. The multi-rotor hydrogen energy drone according to claim 4, characterized in that, The arm span is a hollow arm span, and the arm span is communicated with the "X"-shaped bracket.

6. The multi-rotor hydrogen energy drone according to claim 5, wherein The first hydrogen pipeline is accommodated in the "X"-shaped bracket; the second hydrogen pipeline is arranged in the arm span.

7. The multi-rotor hydrogen energy drone according to claim 3, wherein A wind guide cover is arranged on the air-cooled stack, and the wind guide cover extends from one long side of the air-cooled stack to the other long side; and the cover opening of the wind guide cover is arranged opposite to the brushless motor.

8. The multi-rotor hydrogen energy unmanned aerial vehicle according to claim 3, wherein, The paddle blade is a single paddle blade; the total rated output power of the air-cooled reactor ≥ 10 kW; the air-cooled reactor is an air-cooled reactor using thin graphite bipolar plates; the performance parameter of the air-cooled reactor is 0.51 V @ 0.9 A / cm 2 , active area 250 cm 2 .

9. The multi-rotor hydrogen energy unmanned aerial vehicle according to claim 1, wherein A mission payload is arranged on one side of the UAV body far from the gaseous hydrogen storage cylinder; the mission payload is mounted on the UAV body.

10. The multi-rotor hydrogen energy unmanned aerial vehicle according to claim 1, wherein, At least two gaseous hydrogen storage cylinders are provided, and the two gaseous hydrogen storage cylinders are arranged in parallel. Eight arm spans are provided, and the eight arm spans are evenly arranged on the side of the UAV body to form a cross-octarotor hydrogen energy UAV body; the maximum wheelbase of the octarotor hydrogen energy UAV body is 2250 mm.

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