Arrangement design method of umbrella-shaped support frame for changing thickness of leading edge of wing

Abstract

The invention provides an arrangement design method of an umbrella-shaped support frame for changing the thickness of a leading edge of a wing, which comprises the following steps of: acquiring scattered point data of n airfoils on the wing, determining an initial airfoil profile contour arc length L1, a target airfoil profile contour arc length L2 and a difference value between the two contour arc lengths, and determining an opening size of the leading edge of the wing; the radius r of the circular section of each connecting rod in the umbrella-shaped supporting frame, the connecting positions A and B of the umbrella-shaped supporting frame and the wing and the connecting position C of the umbrella-shaped supporting frame and the driver are designed, and a two-dimensional arrangement scheme of the umbrella-shaped supporting frame on the two-dimensional wing is obtained; the umbrella-shaped supporting frames are arrayed in the wingspan direction, a three-dimensional arrangement scheme on the three-dimensional wing is obtained, and optimization design is conducted on the number N and the spacing distance Di of the steel frames arranged in the wingspan direction. According to the umbrella-shaped supporting frame for changing the thickness of the front edge of the wing, the weight of the wing structure can be obviously reduced, the fuel efficiency and the loading capacity of an aircraft are improved, the risks of abrasion and faults are fundamentally reduced, and the reliability is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of variable wing technology, and particularly relates to a layout design method of an umbrella-shaped support frame for changing the thickness of the wing leading edge. Background Art

[0002] With the rapid development of modern aviation industry, the design of aircraft is evolving towards multi-functionality, high efficiency and high adaptability. Especially in the transonic flight mission, the aircraft needs to maintain excellent aerodynamic performance and structural stability under different flight speeds and working conditions, which puts forward higher requirements for the wing design. Due to its fixed geometric shape, the traditional rigid wing is difficult to meet the requirements of drag reduction and lift increase simultaneously at different flight speeds.

[0003] The relative thickness of the wing leading edge has a significant impact on the maximum lift coefficient and hypersonic drag of the wing. At low speeds, a blunt leading edge helps to delay the separation of the airflow, enhance the lift performance, and thus improve the low-speed stability and controllability of the aircraft. Especially at a large angle of attack, the blunt leading edge design can effectively postpone the stall phenomenon, provide a higher lift coefficient, and make the aircraft perform better during takeoff, landing and low-speed cruise. However, at high speeds, a thin leading edge design can significantly reduce wave drag and pressure drag, and improve the aerodynamic efficiency of the aircraft. The thin leading edge allows the airflow to flow around the wing more smoothly, reducing drag while ensuring the aerodynamic stability of the aircraft at high speeds. Therefore, in the transonic flight mission, different flight speeds have different geometric shape requirements for the wing leading edge to meet the corresponding aerodynamic requirements.

[0004] In the prior art, when the traditional rigid hinge or slider mechanism is used to adjust the thickness of the wing leading edge, the following problems still exist: (1) The traditional mechanical adjustment mechanism often requires multiple rigid components and complex hinge or slider structures, resulting in a significant increase in the weight of the overall system. This increase in weight not only limits the fuel efficiency of the aircraft, but also has an adverse impact on the payload capacity; (2) Due to the existence of multiple mechanical connection points in the rigid mechanism, problems such as wear, clearance or jamming are likely to occur during long-term use, resulting in insufficient system reliability and the need for frequent maintenance, thus increasing the operating cost; (3) During the process of dynamically adjusting the thickness of the wing leading edge by the traditional rigid mechanism, the response speed is slow and the control accuracy is limited, and the comprehensive aerodynamic performance of the aircraft under full-speed flight conditions cannot be fully improved. Summary of the Invention

[0005] The purpose of the present invention is to solve one or more of the above problems, and provide a layout design method of an umbrella-shaped support frame for changing the thickness of the wing leading edge.

[0006] To achieve the above purpose, the technical solution provided by the present invention is:

[0007] A method for arranging and designing an umbrella-shaped support frame for changing the thickness of the leading edge of a wing is provided, including the following steps:

[0008] Step 1: Collect n airfoil scatter point data on the wing, and determine the initial airfoil profile arc length L1 and the target airfoil profile arc length L2;

[0009] Step 2: Determine the opening size of the leading edge of the wing based on the difference between the initial airfoil profile arc length L1 and the target airfoil profile arc length L2;

[0010] Step 3: Design the circular cross-section radius r of each connecting rod in the umbrella-shaped support frame, the connection positions A and B of the umbrella-shaped support frame with the wing, and the connection position C of the umbrella-shaped support frame with the actuator; Use the finite element method to simulate the two-dimensional wing, and extract the deformed airfoil data. Define the error between the deformed airfoil and the target airfoil as the deformation accuracy of the two-dimensional wing; Taking the maximum stress, driving force, driving stroke, and bearing constant aerodynamic load as constraint conditions, and taking the deformation accuracy requirement of the two-dimensional wing as the optimization goal, optimize the design of the circular cross-section radius r and the connection positions A, B, and C to obtain the two-dimensional layout plan of the umbrella-shaped support frame on the two-dimensional wing;

[0011] Step 4: Define the two-dimensional layout plan of the umbrella-shaped support frame obtained in Step 3 as a set of steel frames, and array the steel frames along the wingspan direction to obtain a three-dimensional layout plan of multiple sets of steel frames on the three-dimensional wing; Use the finite element method to simulate the three-dimensional wing, and define the error between the deformed airfoil and the target airfoil as the deformation accuracy of the three-dimensional wing; Taking the deformation accuracy requirement of the three-dimensional wing as the optimization goal, optimize the design of the number N of steel frames arranged along the wingspan direction and the spacing distance D between adjacent steel frames i for optimization design.

[0012] Furthermore, in Step 1, the calculation methods of the arc length L1 of the initial airfoil profile and the arc length L2 of the target airfoil profile are the same, and specifically include the following sub-steps:

[0013] Step 1.1: Collect n airfoil scatter point data on the wing, calculate the distance d between adjacent two airfoil scatter points i , and use the following formula to calculate the approximate arc length S from n airfoil scatter points to the wing tip j :

[0014]

[0015] where d i represents the distance between the (i - 1)th and the ith airfoil scatter points, i traverses from 2 to j, and j traverses from 2 to n;

[0016] Step 1.2: For the approximate arc length S from n airfoil scatter points to the wing tip in Step 1.1 jParametrize to calculate the normalized parameter t, construct a B-spline curve based on the normalized parameter t, and obtain the fitted airfoil profile function f(t) as shown in the following equation:

[0017]

[0018] where N i,k (t) represents the i-th B-spline basis function with order k, and P i represents the control point, and the control points are obtained by fitting the airfoil scatter points using the least squares method;

[0019] Step 1.3: Calculate the arc length L of the airfoil profile according to the following arc length formula:

[0020]

[0021] where f′(t) represents the derivative of the fitted airfoil profile function f(t).

[0022] Furthermore, in Step 1.2, the normalized parameter t is expressed as: j = 1, 2,..., n, where S j represents the approximate arc length from the j-th airfoil scatter point to the wing tip, and S n represents the approximate arc length from the n-th airfoil scatter point to the wing tip.

[0023] Furthermore, in Step 2, the opening size of the leading edge of the wing is calculated by the following formula:

[0024]

[0025] where s represents the position coordinate of the opening at the leading edge of the wing, L(s) represents the arc length of the opening at the leading edge of the wing, d represents the linear dimension perpendicular to the central axis of the wing at the opening of the leading edge of the wing, and f(s) represents the function value corresponding to the position coordinate s of the opening at the leading edge of the wing.

[0026] Furthermore, in Step 3, the radius r of the circular cross-section and the connection positions A, B, and C are optimized using the following formula:

[0027]

[0028] where f represents the deformed airfoil curve, f * represents the target airfoil curve, σ represents the deformed stress distribution function, [σ] represents the allowable stress, P represents the constant aerodynamic load, X represents the driving stroke, F represents the driving force, [F] represents the allowable value of the driving force, [X] represents the allowable value of the driving stroke, and [P] represents the allowable value of the constant aerodynamic load.

[0029] Further, in step 4, the number of steel frames N arranged along the wingspan direction and the spacing distance D between adjacent steel frames are optimized using the following formula: i For optimization:

[0030]

[0031] where e r represents the maximum error between the deformed three-dimensional wing and the target airfoil over the entire wing surface, [W] represents the maximum allowable weight of the wing, W represents the weight of the wing, and b represents the span length.

[0032] Further, the umbrella-shaped support frame is driven by a linear actuator to achieve changes in the leading-edge thickness of the wing.

[0033] Further, the connections between the umbrella-shaped support frame and the wing, and between the linear actuator and the umbrella-shaped support frame are all hinged.

[0034] The advantages of the present invention are as follows:

[0035] 1. The umbrella-shaped support frame designed in the present invention serves as a compliant mechanism, achieving the transmission of motion and force through elastic deformation, replacing traditional mechanical connections such as rigid hinges or slider mechanisms. This can significantly reduce the weight of the wing structure, improve the fuel efficiency and payload capacity of the aircraft; each group of steel frames is connected to the wing at only 4 positions. Since the number of mechanical connection points is greatly reduced, the risk of wear and failure is fundamentally reduced, the maintenance cost is lowered, and the system reliability is improved.

[0036] 2. The present invention obtains the optimal layout scheme of the umbrella-shaped support frame on the wing through design optimization. The umbrella-shaped support frame has a fast response speed in controlling the change of the leading-edge thickness of the wing, and can achieve high-precision control during the dynamic adjustment process, enabling the wing to adjust the leading-edge thickness in real time according to the flight speed, and being applicable to cross-domain flight. Description of the Drawings

[0037] Through the following description with reference to the drawings, the features and advantages of the present invention will become more easily understood. The drawings are not drawn to scale, and some features are enlarged or reduced to show the details of specific components. In the drawings:

[0038] Figure 1 is the front view of the two-dimensional layout of the umbrella-shaped support frame in the present invention;

[0039] Figure 2 is the orthographic isometric view of the two-dimensional layout of the umbrella-shaped support frame in the present invention;

[0040] Figure 3 is the schematic diagram of the initial airfoil profile and the target airfoil profile in the present invention;

[0041] Figure 4It is a schematic diagram before and after the thickness change of the three-dimensional airfoil in the example of the present invention. Detailed implementation manners

[0042] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments of the present invention. It should be noted that the following detailed description of the present invention is only for the purpose of illustration and does not limit the present invention.

[0043] The present invention provides a layout design method for an umbrella-shaped support frame that changes the thickness of the leading edge of a wing, which is used to install an umbrella-shaped support frame inside the leading edge of the wing and is applicable to aircraft flying in a cross-speed range, so as to change the thickness of the leading edge of the wing according to actual needs, enabling the wing to flexibly adjust the leading edge shape according to the actual flight speed, enhancing lift at low speeds and reducing drag at high speeds, thereby improving the comprehensive performance of the aircraft in the full speed range.

[0044] As Figure 1 、 2 shown, the umbrella-shaped support frame is composed of four connecting rods with a circular cross-section. The connecting rods are symmetrically arranged in pairs. One end of the four connecting rods is respectively hinged to the wing skin on the same side, and the other ends are all connected to the same point and hinged to the driving mechanism; regarding the umbrella-shaped support frame on the two-dimensional wing as a group of steel frames, on the three-dimensional wing, multiple groups of steel frames are arrayed in the span direction, and the formed compliant mechanism drives the deformation of the wing skin through structural deformation, thereby changing the thickness of the leading edge of the wing. Compared with the traditional mechanical transmission mechanism, it can effectively reduce the weight.

[0045] The present invention provides a layout design method for an umbrella-shaped support frame that changes the thickness of the leading edge of a wing, including the following steps:

[0046] Step 1: Collect n airfoil scatter point data on the wing and determine the initial airfoil contour arc length L1 and the target airfoil contour arc length L2;

[0047] Step 2: Determine the opening size of the leading edge of the wing based on the difference between the initial airfoil contour arc length L1 and the target airfoil contour arc length L2;

[0048] Step 3: Design the circular cross-section radius r of each connecting rod in the umbrella-shaped support frame, the connection positions A and B of the umbrella-shaped support frame with the wing, and the connection position C of the umbrella-shaped support frame with the driver; perform simulation on the two-dimensional wing using the finite element method and extract the airfoil data after deformation. Define the error between the deformed airfoil and the target airfoil as the deformation accuracy of the two-dimensional wing; taking the maximum stress, driving force, driving stroke, and constant aerodynamic load as constraints and the deformation accuracy requirement of the two-dimensional wing as the optimization objective, optimize and design the circular cross-section radius r and the connection positions A, B, and C to obtain the two-dimensional layout plan of the umbrella-shaped support frame on the two-dimensional wing;

[0049] Step 4: Define the two-dimensional layout scheme of the umbrella-shaped support frame obtained in Step 3 as a group of steel frames, and array the steel frames along the wingspan direction to obtain a three-dimensional layout scheme of multiple groups of steel frames on the three-dimensional wing; perform simulation on the three-dimensional wing using the finite element method, and define the error between the deformed airfoil and the target airfoil as the deformation accuracy of the three-dimensional wing; take the deformation accuracy requirement of the three-dimensional wing as the optimization objective, and optimize the number N of the steel frames arranged along the wingspan direction and the spacing distance D between adjacent steel frames i for optimal design.

[0050] The umbrella-shaped support frame designed in the present invention realizes the transmission of motion and force through structural elastic deformation, replaces the traditional rigid hinge or slider design, significantly reduces the weight of the wing structure, and improves the fuel efficiency and load capacity of the aircraft. The connection design between the umbrella-shaped support frame and the wing greatly reduces the mechanical connection points, fundamentally reduces the risk of wear and failure, simplifies the system maintenance, and significantly improves the reliability and economy of the system. In addition, the response speed is fast, and high-precision control can be achieved during the dynamic adjustment process, enabling the wing to adjust the leading-edge thickness in real time according to the flight speed. At low speeds, the leading-edge shape adjusted by the umbrella-shaped support frame can effectively enhance the lift, while at high speeds, it can significantly reduce the drag, thereby optimizing the aerodynamic performance and improving the comprehensive performance of the aircraft under full-speed flight conditions. Therefore, it not only solves the deficiencies in the traditional technology, but also provides a more efficient and reliable solution for the cross-speed flight of the aircraft.

[0051] Next, each step will be described in detail.

[0052] The calculation methods of the arc length L1 of the initial airfoil profile and the arc length L2 of the target airfoil profile are the same, and specifically include the following sub-steps:

[0053] Step 1.1: Collect n airfoil scatter point data on the wing, calculate the distance d between adjacent two airfoil scatter points i , and calculate the approximate arc length S from n airfoil scatter points to the wing tip using the following formula j :

[0054]

[0055] where d i represents the distance between the (i - 1)-th and the i-th airfoil scatter points, i traverses from 2 to j, and j traverses from 2 to n.

[0056] Step 1.2: Parameterize the approximate arc length S from n airfoil scatter points to the wing tip in Step 1.1 j , calculate the normalized parameter t, and construct a B-spline curve based on the normalized parameter t to obtain the fitted airfoil profile function f(t), as shown in the following formula:

[0057]

[0058] Among them, N i,k (t) represents the i-th B-spline basis function with order k, usually 4, and P i represents the control points, and the control points are obtained by fitting the airfoil scatter points through the least squares method; the normalized parameter t is expressed as: j = 1, 2,..., n, where S j represents the approximate arc length from the j-th airfoil scatter point to the wing tip, and S n represents the approximate arc length from the n-th airfoil scatter point to the wing tip.

[0059] Step 1.3: Calculate the airfoil profile arc length L according to the following arc length formula:

[0060]

[0061] Among them, f′(t) represents the derivative of the fitted airfoil profile function f(t).

[0062] In Step 2, in order to meet the design requirements of the deformable wing, there is a difference in the arc length of the airfoil profile before and after deformation, which leads to different geometric dimensions of the two. To ensure the coordination of the geometric relationship of the wing during the deformation process, a design strategy of opening the leading edge of the wing is adopted. This opening effectively solves the problem of geometric mismatch caused by the change in the airfoil profile arc length and ensures the smooth deformation of the wing structure; the size of the opening at the leading edge of the wing is calculated by the following formula:

[0063]

[0064] Among them, s represents the position coordinate of the opening at the leading edge of the wing, L(s) represents the arc length of the opening at the leading edge of the wing, d represents the linear dimension perpendicular to the wing's central axis at the opening of the leading edge of the wing, and f(s) represents the function value corresponding to the position coordinate s of the opening at the leading edge of the wing. According to the first equation, the coordinate position of the opening at the leading edge of the wing can be determined, and substituting it into the second equation can determine the vertical dimension of the opening at the leading edge of the wing.

[0065] In Step 3, the following formula is used to optimize the radius r of the circular cross-section and the connection positions A, B, and C:

[0066]

[0067] Among them, f represents the deformed airfoil curve, and f * represents the target airfoil curve, σ represents the deformed stress distribution function, [σ] represents the allowable stress, P represents the constant aerodynamic load, X represents the driving stroke, F represents the driving force, [F] represents the allowable value of the driving force, [X] represents the allowable value of the driving stroke, and [P] represents the allowable value of the constant aerodynamic load.

[0068] In step 4, the number of steel frames N arranged along the wingspan direction and the spacing distance D between adjacent steel frames are optimized using the following formula: i For optimization:

[0069]

[0070] where e r represents the maximum error between the deformed three-dimensional wing and the target airfoil over the entire wing surface, [W] represents the maximum allowable weight of the wing, W represents the weight of the wing, and b represents the wingspan.

[0071] The umbrella-shaped support frame is driven by a linear actuator to achieve changes in the leading-edge thickness of the wing; the connection points A and B of the umbrella-shaped support frame to the wing are hinged; the linear actuator is arranged at point C of the umbrella-shaped support frame and is hinged to the umbrella-shaped support frame. The umbrella-shaped support frame is connected at points A-C-A and B-C-B, so the positions of A, B, and C determine the length of the umbrella-shaped support frame. The linear actuator drives point C to move linearly backward, and the force and motion will be transmitted through the umbrella-shaped support frame to control the contraction and thinning of the wing leading edge.

[0072] Next, it will be described according to specific examples.

[0073] In this example, the wingspan b = 300 mm, and it bears a constant aerodynamic load of P = 100 Pa during the deformation process. The target airfoil contracts inward after deformation, and the overall wing becomes thinner. A linear drive mechanism is used, with a driving force F ≤ 500 N, a linear drive stroke X ≤ 15 mm, a maximum stress [σ] = 0.8σ s , where σ s is the yield strength of the material, the two-dimensional airfoil forming accuracy δ1 ≤ 2.0 mm, the three-dimensional airfoil forming accuracy δ2 ≤ 3.0 mm, and the weight of the three-dimensional wing W ≤ 600 g. The umbrella-shaped support frame and the wing are both made of aluminum alloy material, and the wing has an upper and lower symmetric structure. Based on the symmetry principle, the upper wing surface of the wing is selected as the design object.

[0074] The relevant data of the initial airfoil profile and the target airfoil profile are shown in the following table, with the origin of the coordinate axes and the x-axis and y-axis as Figure 3 shown.

[0075] Table 1 Initial airfoil and target airfoil data

[0076]

[0077]

[0078] Using the above data, the arc length L of the airfoil profile is calculated by the B-spline method. After calculation, the arc length L1 of the initial airfoil profile is 516 mm, and the arc length L2 of the target airfoil profile is 496 mm. The difference between the arc length L1 of the initial airfoil profile and the arc length L2 of the target airfoil profile is 20 mm. Through the formula the opening coordinate s of the leading edge of the wing is obtained as 4 mm, and the vertical dimension d of the opening of the leading edge of the wing is calculated as 15 mm.

[0079] Based on the performance index that the forming accuracy of the two-dimensional airfoil (i.e., the difference between the ordinate of any chordwise point of the airfoil curve of the deformed wing and the target airfoil curve) is less than the required accuracy, the maximum stress, driving force, driving stroke, and the constant aerodynamic load are constrained, and the installation position of the umbrella-shaped support frame on the wing is optimized. After the optimization design, the abscissa positions of the connection positions A, B, and C are obtained, that is, X A = 57.39 mm, X B = 190.33 mm, X C = 260 mm, and the radius of the circular cross-section of the umbrella-shaped support frame is r = 1 mm.

[0080] The optimized position of the above umbrella-shaped support frame is extended and applied to the three-dimensional wing design. With the three-dimensional airfoil forming accuracy as the goal, the number and spacing of the steel frame arrays are optimized. After optimization, N = 7 is finally determined, and the spacing between adjacent steel frames is An umbrella-shaped support frame composed of 7 groups of spanwise uniformly distributed steel frames is used to drive the wing to achieve the deformation of the thickness change. The configuration of each group of steel frames is basically the same as the two-dimensional airfoil design form.

[0081] In summary, the final design determines that the materials of the upper and lower skins of the wing surface are 2024 aluminum alloy, the skin thickness is 1 mm, the umbrella-shaped support frame is made of 7075 aluminum alloy, the designed cross-sectional area of the umbrella-shaped support frame is 1 mm, and the weight of the three-dimensional wing is 480 g. The leading edge of the wing adopts an opening design with an upper and lower spacing of 15 mm, fully considering the external aerodynamic load and the nonlinear large deformation effect of the structure. Under the initial airfoil, the opening at the leading edge of the wing is blocked by the skin, and this part of the skin will retract into the wing during the wing deformation process. Under the driving action of the umbrella-shaped support frame, when the initial airfoil deforms to the target airfoil, the deformation accuracy meets the design requirements, and the design results are as Figure 4 shown.

[0082] Finally, it should be noted that the features mentioned and / or shown in the above description of the exemplary embodiments of the present invention can be combined in the same or similar manner into one or more other embodiments, combined with the features in other embodiments or replace the corresponding features in other embodiments. The technical solutions obtained through such combination or substitution should also be regarded as being included within the protection scope of the present invention.

Claims

1. A method for designing an arrangement of an umbrella-shaped support frame for changing the thickness of a wing leading edge, characterized in that: The following steps are involved: Step 1: Collect n airfoil scattered point data on the wing, and determine the initial airfoil profile arc length L1 and the target airfoil profile arc length L2; Step 2: Determine the size of the wing leading edge opening based on the difference between the initial airfoil profile arc length L1 and the target airfoil profile arc length L2; Step 3: Design the circular cross-sectional radius r of each connecting rod in the umbrella support frame, the connection positions A and B between the umbrella support frame and the wing, and the connection position C between the umbrella support frame and the driver; The finite element method is used to simulate the two-dimensional wing, and the deformed airfoil data is extracted. The error between the deformed airfoil and the target airfoil is defined as the deformation accuracy of the two-dimensional wing. The maximum stress, driving force, driving stroke and constant aerodynamic load are used as constraints, and the deformation accuracy requirement of the two-dimensional wing is used as the optimization target. The circular section radius r and the connection positions A, B, and C are optimized to obtain the two-dimensional layout of the umbrella support frame on the two-dimensional wing. Step 4: define the two-dimensional arrangement of the umbrella support frame obtained in step 3 as a group of steel frames, arrange the steel frames in an array along the wingspan direction, and obtain a three-dimensional arrangement of multiple groups of steel frames on the three-dimensional wing; use the finite element method to simulate the three-dimensional wing, and define the error between the deformed airfoil and the target airfoil as the deformation accuracy of the three-dimensional wing; Taking the deformation accuracy requirement of the three-dimensional wing as the optimization target, the number N of steel frames arranged along the wingspan direction and the spacing D between adjacent steel frames are calculated. i Carry out optimized design.

2. The layout design method according to claim 1, characterized in that: In step 1, the arc length L1 of the initial airfoil profile and the arc length L2 of the target airfoil profile are calculated in the same way, which specifically includes the following sub-steps: Step 1.1: Collect n airfoil scattered point data on the wing and calculate the distance d between two adjacent airfoil scattered points i , use the following formula to calculate the approximate arc length S from n airfoil scattered points to the wing tip j : Among them, d i Represents the distance between the i-1th and i-th airfoil scatter points, i traverses from 2 to j, and j traverses from 2 to n; Step 1.2: Approximate arc length S from the n airfoil scattered points in step 1.1 to the wing tip j Parameterize and calculate the normalized parameter t. Based on the normalized parameter t, construct the B-spline curve to obtain the fitted airfoil profile function f(t), as shown in the following formula: Among them, N i,k (t) represents the i-th B-spline basis function, with order k, P i represents the control points, which are obtained by fitting the airfoil scattered points by the least square method; Step 1.3: Calculate the airfoil profile arc length L according to the following arc length formula: Where f′(t) represents the derivative of the fitted airfoil profile function f(t).

3. The layout design method according to claim 2, characterized in that: In step 1.2, the normalization parameter t is expressed as: Among them, S j represents the approximate arc length from the jth airfoil scatter point to the wing tip, S n Represents the approximate arc length from the nth airfoil scatter point to the wingtip.

4. The layout design method according to claim 2, characterized in that: In step 2, the wing leading edge opening size is calculated using the following formula: Among them, s represents the position coordinate of the leading edge opening of the wing, L(s) represents the arc length of the leading edge opening of the wing, d represents the straight line dimension perpendicular to the wing centerline at the leading edge opening of the wing, and f(s) represents the function value corresponding to the position coordinate s of the leading edge opening of the wing.

5. The layout design method according to claim 1, characterized in that: In step 3, the circular section radius r and the connection positions A, B, and C are optimized using the following formula: Among them, f represents the airfoil curve after deformation, f * represents the target airfoil curve, σ represents the stress distribution function after deformation, [σ] represents the allowable stress, P represents the constant aerodynamic load, X represents the driving stroke, F represents the driving force, [F] represents the allowable value of the driving force, [X] represents the allowable value of the driving stroke, and [P] represents the allowable value of the constant aerodynamic load.

6. The layout design method according to claim 1, characterized in that: In step 4, the following formula is used to calculate the number of steel frame groups N arranged along the wingspan direction and the spacing distance D between adjacent steel frames: i To optimize: Among them, e r It represents the maximum error between the three-dimensional wing and the target airfoil on the entire wing surface after deformation, [W] represents the maximum allowable weight of the wing, W represents the wing weight, and b represents the span.

7. The layout design method according to claim 1, characterized in that: The parachute support is driven by a linear actuator to achieve the change in the thickness of the wing leading edge.

8. The layout design method according to claim 7, characterized in that: The connection between the umbrella support frame and the wing, and between the linear drive and the umbrella support frame are all hinged.

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