Wing elliptical lift force distribution design method based on graphical method, equipment and medium

Abstract

The invention discloses a wing elliptical lift force distribution design method based on a graphical method, equipment and a medium, and relates to the field of unmanned aerial vehicle design. The method comprises the following steps: determining lift force demand and wing plane shape constraint, establishing a reference rectangle required by a graphical method, mapping half of the required lift force into a reference rectangle area, solving geometric parameters of the reference rectangle, establishing a reference ellipse with the area equal to that of the reference rectangle, and mapping the spanwise distribution of the lift force of the ellipse to the height of the ellipse. And mapping the height of the ellipse to a wing torsion angle, solving a distribution curve of the wing torsion angle along a spanwise direction, arranging a wing profile according to the wing torsion angle, stretching out a half wing, and performing symmetry on the half wing to obtain a complete wing. According to the method, the design of the elliptical lift force distribution flat and straight wing is obtained by using the graphical method, and the method has the advantages of concrete implementation process, simple engineering operation, easy parameterization or programming design and the like.

Description

Technical Field

[0001] This application belongs to the field of unmanned aerial vehicle (UAV) design technology, and in particular relates to a method, device and medium for designing elliptical lift distribution of wings based on graphical methods. Background Technology

[0002] Lift-induced drag, also known as induced drag, occurs when an aircraft wing generates lift. Due to the pressure difference between the upper and lower wing surfaces, the high-pressure airflow on the lower surface flows around the wingtip and upwards, forming rotating wingtip vortices. These vortices alter the airflow direction, causing the lift vector, originally perpendicular to the flight direction, to tilt backwards. The horizontal component of these vortices constitutes induced drag. Lift-induced drag is a necessary cost in generating lift. For low Mach number fixed-wing aircraft, lift-induced drag is one of the main sources of cruise drag. For fixed-wing UAVs, lift-induced drag accounts for approximately 40% to 50% of the total drag.

[0003] There are many ways to reduce lift-induced drag. For medium and large aircraft, such as passenger planes and large fixed-wing UAVs, the influence of wingtip vortices can be weakened by adding wingtip devices (winglets, vortex diffusers, etc.). However, for small fixed-wing UAVs, especially those with folding requirements for components such as wings, such as tube-launched or air-launched UAVs, it is basically impossible to add effective wingtip devices due to geometric constraints.

[0004] Another more traditional method to reduce lift-induced drag is to design the wing loading as an "elliptical distribution." According to Prandtl's lift line theory, the induced drag coefficient... satisfy:

[0005] in, For lift coefficient, For aspect ratio, This is the spanwise efficiency factor (Oswald factor). When the lift is elliptical along the spanwise direction... The induced drag reaches the theoretical minimum, while the non-elliptical wing loading will lead to... This leads to increased induced drag. Traditional elliptical wing loading distribution design primarily employs two approaches: 1) Designing the wing planform directly as an ellipse, as seen in the Japanese Zero fighter during World War II. This design places high demands on structural strength and manufacturing processes, and achieving an elliptical lift distribution design for small fixed-wing UAVs is costly. 2) Based on the elliptical circulation distribution law, the calculus equations are solved, and the spanwise profile of the wing requires the lift coefficient distribution to derive the spanwise airfoil distribution. However, this method requires iterative numerical solutions, making its engineering implementation complex and hindering the rapid realization of the elliptical lift distribution of the wing.

[0006] The technical problem to be solved by this application is: for low Mach number straight wings of UAVs, under the premise of given total lift requirements and wing planar shape constraints, to propose a theoretically clear and simple implementation method for elliptical lift (or elliptical wing loading) distribution design: based on the graphical method of lift distribution, the originally complex wing airfoil spanwise design process is simplified, and the elliptical lift distribution of the wing is designed efficiently. Summary of the Invention

[0007] The purpose of this application is to overcome the problems of the prior art by disclosing a design method and medium for elliptical lift distribution of airfoils based on the graphical method. This application uses the graphical method to obtain the design of a straight airfoil with elliptical lift distribution, which has the advantages of visualized implementation process, simple engineering operation, and easy parameterization or programming design.

[0008] The objective of this application is achieved through the following technical solution: A graphical method for designing elliptical lift distribution in airfoils, comprising: S1: Determine lift requirements and wing planar shape constraints; S2: Establish a reference rectangle; S3: Map half of the required lift coefficient to the area of ​​the reference rectangle; S4: Solve for the geometric parameters of the reference rectangle; S5: Create a reference ellipse with the same area as the reference rectangle; S6: The spanwise distribution law of elliptical lift is mapped to the ellipse height, that is, the distribution of the reference ellipse height along the horizontal axis is mapped to the spanwise distribution of the wing lift coefficient; S7: Ellipse height mapped to wing twist angle; S8: Solve for the wing twist angle distribution curve in the extension direction; S9: Based on the angular relationship of the airfoil at any position along the span, twist and stretch out half of the wing; S10: Symmetrical processing of half a wing piece yields a complete wing.

[0009] According to a preferred embodiment, in step S1, the required total lift coefficient is set to... The straight wingspan is The straight wing chord is Step S2 includes: establishing a reference rectangle OARH, and setting points. The origin of the coordinate system.

[0010] According to a preferred embodiment, step S3 includes: for the reference rectangle OARH, determining the required lift coefficient. If half of the area is mapped to the area of ​​the reference rectangle, then:

[0011]

[0012] in, Indicates the wing's half span. The lift coefficient that a wing with a unit span can produce is determined by the airfoil. This indicates the height parameter of the reference rectangle OARH. The lift coefficient surface density specified when mapping lift demand to the area of ​​a reference rectangle.

[0013] According to a preferred embodiment, step S4 includes: calculating the lift coefficient that can be generated by the airfoil corresponding to the unit span of the wing. And mapped to the height parameter of the reference rectangle OARH. Then we have: ; Step S4 also includes: Based on the solution obtained Select the desired airfoil from the airfoil library and, based on the airfoil's lift characteristics, determine the overall installation angle under the condition of no airfoil twist angle. .

[0014] According to a preferred embodiment, step S5 includes: mapping the height of the reference rectangle. As a reference ellipse for construction; To solve for the reference ellipse OAB, let P be the intersection point of the reference rectangle and the reference ellipse. Make the areas of the reference ellipse and the reference rectangle equal so that the reference ellipse receives the same mapped lift force as the reference rectangle. ,have to:

[0015] in, This represents the ordinate of the intersection point P of the reference rectangle and the reference ellipse. Let OAB be the intersection point of the reference ellipse and the ordinate axis. Then, the analytical expression of the reference ellipse OAB is: .

[0016] According to a preferred embodiment, step S7 includes: Based on the lift coefficient versus angle of attack curve of the selected airfoil Curve, find the lift coefficient that satisfies The angle of attack at that time is the airfoil rotation angle at the wingtip. ; For the wing root, find the wing root airfoil rotation angle that satisfies the following formula for the lift coefficient. :

[0017] Obtain the airfoil root angle : .

[0018] According to a preferred embodiment, step S8 includes: Based on the mapping relationship of the reference ellipse, for any spanwise position M of the wing, the following relationship is established with respect to its corresponding point N on the reference ellipse:

[0019] in, This represents the local twist angle of the airfoil at any spanwise position M of the wing. This represents the spanwise coordinates at any spanwise position M; According to a preferred embodiment, step S9 includes: based on solving the airfoil local twist angle at any spanwise position M of the wing. and with airfoil local twist angle The variation law controls the airfoil to twist and stretch along the spanwise direction at the same time, thereby obtaining a half-wing with spanwise lift distributed in an elliptical pattern.

[0020] On the other hand, this application also discloses: An electronic device includes: at least one processor; and a memory communicatively connected to said at least one processor; The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the instructions stored in the memory to perform the aforementioned method.

[0021] On the other hand, this application also discloses: A computer-readable storage medium for storing instructions that, when executed, cause the aforementioned method to be implemented.

[0022] The aforementioned main solution and its various further alternative solutions can be freely combined to form multiple solutions, all of which are solutions that can be adopted and are claimed in this application. Those skilled in the art, after understanding the solution of this application, will realize that there are many combinations based on the prior art and common general knowledge, all of which are technical solutions to be protected in this application, and will not be exhaustively listed here.

[0023] The beneficial effects of this application are: This application proposes a design method for a straight airfoil with elliptical lift distribution by establishing a reference rectangle and a reference ellipse and using a graphical method. This method offers advantages such as visualized implementation process, simple engineering operation, and ease of parameterization or programming design. However, this method is only applicable to designing straight fixed wings without shock waves and maintaining good airfoil linearity at common angles of attack. For high-aspect-ratio fixed-wing UAVs operating at low Mach numbers, this method generally meets the relevant requirements. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating the method of this application; Figure 2 This is a schematic diagram of the reference rectangle and reference ellipse for the wing loading design of this application; Figure 3 This is a schematic diagram of the equipment structure in this application. Detailed Implementation

[0025] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0028] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0029] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] Furthermore, it should be noted that unless otherwise specified in this application, the specific structures, connections, positions, power sources, etc. involved are all things that a person skilled in the art can know without creative effort based on the prior art.

[0031] Example 1 refer to Figure 1 and Figure 2 As shown in the figure, this embodiment discloses a design method for elliptical lift distribution of an airfoil based on a graphical method. The design method for elliptical lift distribution of an airfoil based on a graphical method includes the following steps.

[0032] Step S1: Determine the lift requirements and wing planar shape constraints.

[0033] Preferably, in step S1, the required total lift coefficient is set to... The value can be solved simultaneously from the overall design parameters of the first approximate stage, such as the design cruise altitude, design cruise speed, and wing loading. The straight wing span is... The straight wing chord is .

[0034] Step S2: Establish a reference rectangle, including: establishing a reference rectangle OARH, and setting points. Origin of position coordinates Step S3: Map half of the required lift coefficient to the area of ​​the reference rectangle. This includes: mapping the required lift coefficient to the area of ​​the reference rectangle OARH. If half of the area is mapped to the area of ​​the reference rectangle, then:

[0035]

[0036] in, Indicates the wing's half span. The lift coefficient that a wing with a unit span can produce is determined by the airfoil. This indicates the height parameter of the reference rectangle OARH. The lift coefficient surface density, specified to map lift demand to the area of ​​a reference rectangle, is a reference quantity set for dimensionless measurement. Its specific value can be specified based on dimensional constraints during drawing, but it has a definite unit: m. -2 The reference rectangle and the reference ellipse have the same... .

[0037] Step S4: Solve for the geometric parameters of the reference rectangle. This includes solving for the lift coefficient that a unit span wing can produce with respect to the corresponding airfoil. And mapped to the height parameter of the reference rectangle OARH. Then we have: ; Based on the solution obtained Select the desired airfoil from the airfoil library and, based on the airfoil's lift characteristics, determine the overall installation angle under the condition of no airfoil twist angle. .

[0038] Step S5: Create a reference ellipse with the same area as the reference rectangle. This includes: mapping the height of the obtained reference rectangle. Used as a reference for constructing the ellipse. Then solve for the reference ellipse OAB. Let P be the intersection point of the reference rectangle and the reference ellipse. Make the areas of the reference ellipse and the reference rectangle equal so that the reference ellipse obtains the same mapped lift force as the reference rectangle. ,have to:

[0039] in, This represents the ordinate of the intersection point P of the reference rectangle and the reference ellipse. Let OAB be the intersection point of the reference ellipse and the ordinate axis. Then, the analytical expression of the reference ellipse OAB is: .

[0040] Step S6: Map the spanwise distribution law of elliptical lift to the ellipse height, that is, map the distribution of the reference ellipse height along the horizontal axis to the spanwise distribution of the wing lift coefficient.

[0041] Specifically, for the reference rectangle and the reference ellipse, such as Figure 1 As shown, the straight line is mapped to the wingspan, and the height distribution of the straight line and the arc is mapped to the lift distribution along the span of the wing without twist and the wing with twist, respectively.

[0042] Based on the small disturbance linearization theory, within the commonly used cruise angle of attack range, the slope of the lift line of a low Mach number airfoil remains unchanged. Therefore, the spanwise lift distribution law can be directly mapped to the local airfoil twist angle, that is, the height of the arc can be directly mapped to the local airfoil twist angle.

[0043] Step S7: Map the ellipse height to the wing twist angle. S7 includes: mapping the lift coefficient as a function of angle of attack based on the selected airfoil. Curve, find the lift coefficient that satisfies The angle of attack at that time is the airfoil rotation angle at the wingtip. (Usually not greater than 0°).

[0044] For the wing root, find the wing root airfoil rotation angle that satisfies the following formula for the lift coefficient. :

[0045] Obtain the airfoil root angle : .

[0046] Step S8: Solve for the wing twist angle spread distribution curve. This includes: Based on the reference ellipse mapping relationship, for any spanwise position M of the wing, the corresponding point N on the reference ellipse is used to establish the torsion angle control equation:

[0047] in, This represents the local twist angle of the airfoil at any spanwise position M of the wing. This represents the spanwise coordinate at any spanwise position M.

[0048] Step S9: Twist and stretch out half of the wing according to the airfoil's twist angle relationship at any spanwise position. This includes: calculating the local twist angle of the airfoil at any spanwise position M of the wing. and with airfoil local twist angle The variation law controls the airfoil to twist and stretch along the spanwise direction at the same time, thereby obtaining a half-wing with spanwise lift distributed in an elliptical pattern.

[0049] Step S10: Perform symmetry on the obtained half wing to obtain the complete wing.

[0050] In practical applications, the local rotation angle of the airfoil at multiple stations can be solved piecewise by the torsion angle control equation. After arranging a finite number of airfoils according to this rotation angle, an airfoil with an approximately elliptical lift distribution that meets the accuracy requirements of engineering practice can be obtained by establishing a multi-section curved surface.

[0051] This application establishes two reference rectangles and reference ellipses with equal areas; maps the overall installation angle of the non-twisted wing to the height of the reference rectangle; maps the spanwise installation angle variation law of the elliptical lift distribution wing to the height variation law of the reference ellipse; for practical engineering applications, the wing can be obtained by controlling the airfoil to twist while stretching along the spanwise direction using the torsion angle control equation, or the local rotation angle of the airfoil at multiple stations along the spanwise direction can be solved piecewise using the equation, and after arranging a finite number of airfoils according to this rotation angle, an approximate elliptical lift distribution wing with accuracy meeting the requirements of engineering practice can be obtained by establishing a multi-section curved surface.

[0052] This application establishes a reference rectangle and a reference ellipse, and uses a graphical method to obtain a design method for a straight wing with elliptical lift distribution. It has the advantages of visualized implementation process, simple engineering operation, and easy parameterization or programming design.

[0053] Example 2 like Figure 3 As shown, based on Embodiment 1, this embodiment also discloses an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; the specific connection medium between the processor and the memory is not limited in this embodiment of the invention.

[0054] Figure 3 The example used is the connection between the processor and memory via a bus. The bus... Figure 3 The connections between other components are indicated by thick lines and are for illustrative purposes only, not as limiting information. Buses can be divided into address buses, data buses, control buses, etc., but for ease of representation, [the specific bus type is not shown here]. Figure 3 The processor is represented by a single thick line, but this does not imply that there is only one bus or one type of bus. Alternatively, a processor can also be called a controller; there are no restrictions on the name.

[0055] In this embodiment, the memory stores instructions executable by the at least one processor. By executing the instructions stored in the memory, the at least one processor performs the method described in Embodiment 1. The processor can implement... Figure 3 The functions of each module in the device shown.

[0056] The processor is the control center of the device. It can connect to various parts of the control device through various interfaces and lines, and can run or execute instructions stored in memory and call data stored in memory.

[0057] In an alternative design, the processor may include one or more processing units. The processor may integrate an application processor and a modem processor, wherein the application processor primarily handles the operating system, user interface, and applications, while the modem processor primarily handles wireless communication. It is understood that the modem processor may also not be integrated into the processor. In some embodiments, the processor and memory may be implemented on the same chip; in some embodiments, they may also be implemented separately on separate chips.

[0058] The processor can be a general-purpose processor, such as a CPU, digital signal processor, application-specific integrated circuit, field-programmable gate array or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the graphical method for designing elliptical lift distribution of an airfoil disclosed in the embodiments of this invention can be directly manifested as being executed by a hardware processor, or executed by a combination of hardware and software modules within the processor.

[0059] Memory, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules. Memory can include at least one type of storage medium, such as flash memory, hard disk, multimedia card, card-type memory, random access memory (RAM), static random access memory (SRAM), programmable read-only memory (PROM), read-only memory (ROM), and electrically erasable programmable read-only memory (EPROM). Only memory (EEPROM), magnetic storage, magnetic disks, optical disks, etc. A memory is any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited thereto. The memory in embodiments of this invention can also be a circuit or any other device capable of performing storage functions for storing program instructions and / or data.

[0060] By designing and programming the processor, the code corresponding to the graphical method for designing elliptical lift distribution of an airfoil described in the foregoing embodiments can be embedded into the chip, enabling the chip to execute the steps of the method described in the foregoing embodiments during runtime. How to design and program a processor is a technique well-known to those skilled in the art and will not be elaborated upon here.

[0061] Example 3 Based on Embodiment 1, this embodiment also discloses: a computer-readable storage medium for storing instructions that, when executed, cause the method described in Embodiment 1 to be implemented.

[0062] In some alternative embodiments, the present invention also provides that various aspects of the graphical method for designing elliptical lift distribution of an airfoil can be implemented as a program product comprising program code, which, when the program product is run on a device, causes the control device to perform the steps in the graphical method for designing elliptical lift distribution of an airfoil according to various exemplary embodiments of the present invention as described above.

[0063] It should be noted that although several units or sub-units of the apparatus have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of the invention, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided and embodied by multiple units. Furthermore, although the operation of the method of the invention is described in a specific order in the drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0064] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can be implemented in one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs) containing computer-usable program code. The form of a computer program product implemented on ROM, optical memory, etc.

[0065] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a server, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0066] Program code for performing the operations of this invention can be written using any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0067] In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0068] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0069] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1The steps of the functions specified in one or more boxes. The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for designing elliptical lift distribution of an airfoil based on a graphical approach, characterized in that, The graphical method for designing elliptical lift distribution in airfoils includes: S1: Determine lift requirements and wing planar shape constraints; S2: Establish a reference rectangle; S3: Map half of the required lift coefficient to the area of ​​the reference rectangle; S4: Solve for the geometric parameters of the reference rectangle; S5: Create a reference ellipse with the same area as the reference rectangle; S6: The spanwise distribution law of elliptical lift is mapped to the ellipse height, that is, the distribution of the reference ellipse height along the horizontal axis is mapped to the spanwise distribution of the wing lift coefficient; S7: Ellipse height mapped to wing twist angle; S8: Solve for the wing twist angle distribution curve in the extension direction; S9: Based on the angular relationship of the airfoil at any position along the span, twist and stretch out half of the wing; S10: Symmetrical processing of half a wing piece yields a complete wing.

2. The wing elliptical lift distribution design method based on graphical method as described in claim 1, characterized in that, In step S1, let the required total lift coefficient be... The straight wingspan is The straight wing chord is ; Step S2 includes: establishing a reference rectangle OARH, and setting points. The origin of the coordinate system.

3. The wing elliptical lift distribution design method based on graphical method as described in claim 2, characterized in that, Step S3 includes: for the reference rectangle OARH, determining the required lift coefficient. If half of the area is mapped to the area of ​​the reference rectangle, then: in, Indicates the wing's half span. The lift coefficient that a wing with a unit span can produce is determined by the airfoil. This indicates the height parameter of the reference rectangle OARH. The lift coefficient surface density specified when mapping lift demand to the area of ​​a reference rectangle.

4. The wing elliptical lift distribution design method based on graphical method as described in claim 3, characterized in that, Step S4 includes: calculating the lift coefficient that can be generated by the airfoil corresponding to the unit span of the wing. And mapped to the height parameter of the reference rectangle OARH. Then we have: ； Step S4 also includes: Based on the solution obtained Select the desired airfoil from the airfoil library and, based on the airfoil's lift characteristics, determine the overall installation angle under the condition of no airfoil twist angle. .

5. The wing elliptical lift distribution design method based on graphical method as described in claim 4, characterized in that, Step S5 includes: mapping the height of the reference rectangle. As a reference ellipse for construction; To solve for the reference ellipse OAB, let P be the intersection point of the reference rectangle and the reference ellipse. Make the areas of the reference ellipse and the reference rectangle equal so that the reference ellipse receives the same mapped lift force as the reference rectangle. ,have to: in, This represents the ordinate of the intersection point P of the reference rectangle and the reference ellipse. Let OAB be the intersection point of the reference ellipse and the ordinate axis. Then, the analytical expression of the reference ellipse OAB is: 。 6. The wing elliptical lift distribution design method based on graphical method as described in claim 5, characterized in that, Step S7 includes: Based on the lift coefficient versus angle of attack curve of the selected airfoil Curve, find the lift coefficient that satisfies The angle of attack at that time is the airfoil rotation angle at the wingtip. ; For the wing root, find the wing root airfoil rotation angle that satisfies the following formula for the lift coefficient. : Obtain the airfoil root angle : 。 7. The wing elliptical lift distribution design method based on graphical method as described in claim 6, characterized in that, Step S8 includes: Based on the mapping relationship of the reference ellipse, for any spanwise position M of the wing, the following relationship is established with respect to its corresponding point N on the reference ellipse: in, This represents the local twist angle of the airfoil at any spanwise position M of the wing. This represents the spanwise coordinate at any spanwise position M.

8. The wing elliptical lift distribution design method based on graphical method as described in claim 7, characterized in that, Step S9 includes: based on solving the local twist angle of the airfoil at any spanwise position M of the wing. and with airfoil local twist angle The variation law controls the airfoil to twist and stretch along the spanwise direction at the same time, thereby obtaining a half-wing with spanwise lift distributed in an elliptical pattern.

9. An electronic device, characterized in that, include: At least one processor; and a memory communicatively connected to the at least one processor; The memory stores instructions executable by the at least one processor, which executes the instructions stored in the memory to perform the method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store instructions that, when executed, cause the method as described in any one of claims 1 to 8 to be implemented.

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