A method for inverse design of aircraft structure based on structural dynamic characteristics

Abstract

The present invention relates to the field of aerospace engineering technology, and in particular to an aircraft structure inverse design method based on structural dynamic characteristics. The aircraft structure inverse design method based on structural dynamic characteristics first finds an aircraft similar to the design target aircraft based on the known aircraft appearance and function. Then, according to the similarity relationship, the basic structure of the load-bearing parts of the design target aircraft, as well as the mass ratio and distribution position of each part such as the structure, load, and fuel are given. By adjusting the cross-sectional form and material density, a finite element model of the relevant structure is established, and then the inverse design structure of the aircraft is finally determined through calculation and iteration. The inverse design method gives priority to satisfying structural dynamic similarity, is easier to satisfy and converge in terms of the mass and stiffness design of the structure, reduces the number of iterative designs, and requires less aircraft design experience. Therefore, it has advantages in the inverse design process of those who lack aircraft design experience or in some new aircraft.

Description

Technical Field

[0001] The present invention relates to the field of aerospace engineering technology, and in particular to an aircraft structure inverse design method based on structural dynamics characteristics. Background Art

[0002] When analyzing the structure of some aircraft, it is usually necessary to reverse-design its internal structure based on the aircraft's appearance. The traditional method is to design a model based on the aircraft's appearance and personal experience.

[0003] The existing modal test methods have the following problems:

[0004] (1) Since the design input only includes the aircraft shape and there is relatively little effective information, the internal structure of the aircraft relies heavily on the designer's experience, and the design often deviates greatly from the actual aircraft structure results.

[0005] (2) For some new aircraft structures, structural inverse design often cannot be carried out smoothly due to the lack of experience in internal structure design. Summary of the Invention

[0006] The purpose of the present invention is to provide an aircraft structure inverse design method based on structural dynamic characteristics. Since the aircraft structure inverse design method based on structural dynamic characteristics gives priority to satisfying structural dynamic similarity, it is easier to satisfy and converge in terms of structural mass and stiffness design, reducing the number of iterative designs. Moreover, since it requires less aircraft design experience, it has advantages in the inverse design process of aircraft design experience that is insufficient or in some new aircraft.

[0007] The present invention provides an aircraft structure inverse design method based on structural dynamics characteristics, comprising:

[0008] S1. Find a known aircraft that is similar to the target aircraft based on its appearance and function;

[0009] S2. Calculate the mass parameters of the target aircraft using the similarity theory formula. The calculation formula is:

[0010] K m =K1 3

[0011] Where K m is the mass ratio of the design target aircraft to the known aircraft, K1 is the size ratio of the design target aircraft to the known aircraft;

[0012] S3. allocating the design target aircraft mass according to the specific functions of the aircraft and referring to relevant aircraft data;

[0013] S4. Analyze the materials commonly used in this type of aircraft and determine the density of the corresponding parts of the materials;

[0014] S5. Design the main load-bearing components, including wing spars, ribs, and fuselage frames, according to the basic structural form of this type of aircraft. Adjust the cross-sectional dimensions and spacing of each component so that the total mass of the aircraft structure is consistent with that obtained in S3 and the relative density of the structure is consistent with that obtained in S4.

[0015] S6. Establish a corresponding finite element model, attach the fuel tank and load mass obtained in S3 to the relevant positions of the aircraft load-bearing components described in S5, perform corresponding finite element structural dynamics analysis, and compare the results with the structural dynamics characteristics of the design target aircraft;

[0016] When the frequency error is higher than 5%, return to S5;

[0017] When the frequency error is less than 5%, proceed to S7;

[0018] S7. Locally adjust the distribution and structure of each part.

[0019] Preferably, in S1, a known aircraft is selected that has the strongest structural configuration consistency with the design target aircraft, the structural configuration including the number and position of tail fins, the number and position of horizontal stabilizers, the shape and position of wings, and the position and number of engines.

[0020] Preferably, in S2, when K1 in each direction is different, the wingspan ratio is used as a measure of the size ratio between the design target aircraft and the known aircraft.

[0021] Preferably, in S3,

[0022] If the design target aircraft is to be used after 2014, the lower limit of the empty-to-aircraft mass ratio for fighters can be 0.45 to 0.60, the lower limit of the empty-to-aircraft mass ratio for attack aircraft can be 0.41 to 0.54, and the lower limit of the empty-to-aircraft mass ratio for bombers can be 0.37 to 0.42.

[0023] The effective load ratio of fighters can be taken as the upper limit of 0.21 to 0.28, the effective load ratio of attack aircraft can be taken as the upper limit of 0.18 to 0.37, and the effective load ratio of bombers can be taken as the upper limit of 0.14 to 0.19;

[0024] The fuel ratio for fighters can be set at an upper limit of 0.21 to 0.33, the fuel ratio for attack aircraft can be set at an upper limit of 0.17 to 0.33, and the fuel ratio for bombers can be set at an upper limit of 0.40 to 0.62;

[0025] If the design target aircraft was used before 2000, the upper limit of the empty-to-mass ratio for fighters can be 0.45-0.60, the upper limit of the empty-to-mass ratio for attack aircraft can be 0.41-0.54, and the upper limit of the empty-to-mass ratio for bombers can be 0.37-0.42.

[0026] The effective load ratio of fighters can be taken as the lower limit of 0.21 to 0.28, the effective load ratio of attack aircraft can be taken as the lower limit of 0.18 to 0.37, and the effective load ratio of bombers can be taken as the lower limit of 0.14 to 0.19;

[0027] The fuel ratio of fighters can be taken as the lower limit of 0.21 to 0.33, the fuel ratio of attack aircraft can be taken as the lower limit of 0.17 to 0.33, and the fuel ratio of bombers can be taken as the lower limit of 0.40 to 0.62;

[0028] The total of the empty mass ratio, the effective load ratio and the fuel ratio is 100%.

[0029] Preferably, in S4, when the main load-bearing structural materials of the aircraft are different, if a certain material is used for more than 90%, the density of the material shall prevail;

[0030] If a variety of materials are used, use the following formula to estimate the overall material density:

[0031]

[0032] Among them, ρ 总体 is the overall structural material density, ρ i is the material density of the i-th material, μ i is the mass percentage of the i-th material in the overall load-bearing structure.

[0033] Preferably, in S5, the following is included:

[0034] S5.1, adjust the structural quality;

[0035] If the modeling quality is higher than the target quality, increase the area of ​​the rib weight-reducing holes;

[0036] If the modeling quality is lower than the target quality, reduce the area of ​​the rib weight-reducing holes;

[0037] S5.2. Adjust the structure according to the structural bending frequency;

[0038] If the bending frequency calculated during the simulation is too low, the height of the beam structure is increased while the width of the beam structure is reduced while ensuring that the cross-section of the structure remains unchanged.

[0039] If the bending frequency calculated during the simulation is too high, the height of the beam structure should be reduced and the width of the beam structure should be increased while ensuring that the cross-section of the structure remains unchanged.

[0040] S5.3. Adjust the structure according to the torsional bending frequency;

[0041] If the torsional frequency calculated during the simulation is too low, increase the distance between the front and rear wing beams while maintaining the same cross-section of the structure.

[0042] If the torsional frequency calculated during the simulation is too high, the distance between the front and rear wing beams can be reduced while maintaining the structural cross-section.

[0043] Preferably, in S6, when establishing the finite element model, isotropic materials should be used.

[0044] Preferably, in S6, the established finite element model ignores components and structures that have little influence on the quality and stiffness of the structure, such as screws, connections, friction and gaps between the structures.

[0045] Preferably, in S6, the established finite element model can ignore the requirements and influences of the installation, disassembly, and relocation of the structure on the structure.

[0046] Preferably, in S6, in order to facilitate calculation and simulation, the appearance of specific components can be appropriately simplified, and relatively simple geometric configurations can be used instead of complex structures.

[0047] Beneficial effects:

[0048] The technical solution of the present invention first identifies an aircraft similar to the target aircraft based on the known aircraft's appearance and functionality. Based on this similarity, the basic structure of the target aircraft's load-bearing components, along with the mass ratios and distribution of various components, such as the structure, load, and fuel, are determined. By adjusting the cross-sectional form and material density, a finite element model of the relevant structure is established. Calculation and iteration are then used to determine the aircraft's inverse design structure, achieving inverse design of the aircraft structure through simulation, analysis, and comparison.

[0049] The technical solution of the present invention increases the design input, using the known aircraft shape and structural dynamic characteristics (modal frequencies and modal vibration shapes of the aircraft) as input variables to obtain the specific internal structure of the design target aircraft, making the structural inverse design result more accurate;

[0050] The results of this inverse design method are easier to meet and converge in terms of mass and stiffness design of the structure because they give priority to satisfying the similarity of structural dynamics, thus reducing the number of iterative designs.

[0051] Since there is less requirement for aircraft design experience, it has advantages in areas with insufficient aircraft design experience or in the reverse design process of some new aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0053] Figure 1 This is a schematic diagram of the adjustment of the reverse-designed wing cross-section in the present invention;

[0054] Figure 2 This is a flow chart of the inverse design method of the present invention;

[0055] Figure 3 Schematic diagram of the wing structure using the inverse design method of the present invention.

[0056] Description of reference numerals:

[0057] 1: Wing front spar; 2: Wing rear spar; 3: Rib weight-reducing holes; 4: Wing ribs. DETAILED DESCRIPTION

[0058] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0059] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0060] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0061] like Figures 1 to 3 As shown, the present invention provides an aircraft structure inverse design method based on structural dynamics characteristics, which includes:

[0062] S1. Find a known aircraft that is similar to the target aircraft based on its appearance and function;

[0063] S2. Calculate the mass parameters of the target aircraft using the similarity theory formula. The calculation formula is:

[0064] K m =K1 3

[0065] Where K m is the mass ratio of the design target aircraft to the known aircraft, K1 is the size ratio of the design target aircraft to the known aircraft;

[0066] S3. allocating the design target aircraft mass according to the specific functions of the aircraft and referring to relevant aircraft data;

[0067] S4. Analyze the materials commonly used in this type of aircraft and determine the density of the corresponding parts of the materials;

[0068] S5. Design the main load-bearing components, including wing spars, ribs, and fuselage frames, according to the basic structural form of this type of aircraft. Adjust the cross-sectional dimensions and spacing of each component so that the total mass of the aircraft structure is consistent with that obtained in S3 and the relative density of the structure is consistent with that obtained in S4.

[0069] S6. Establish a corresponding finite element model, attach the fuel tank and load mass obtained in S3 to the relevant positions of the aircraft load-bearing components described in S5, perform corresponding finite element structural dynamics analysis, and compare the results with the structural dynamics characteristics of the design target aircraft;

[0070] When the frequency error is higher than 5%, return to S5;

[0071] When the frequency error is less than 5%, proceed to S7;

[0072] S7. Locally adjust the distribution and structure of each part.

[0073] The present invention proposes an aircraft structure inverse design method based on structural dynamic characteristics. The aircraft structure inverse design based on structural dynamic characteristics refers to an analysis and design method that uses the aircraft shape and structural dynamic characteristics (modal frequencies and modal vibration shapes of the aircraft) as input variables to obtain the specific internal structure of the aircraft.

[0074] The technical solution of the present invention first identifies an aircraft similar to the target aircraft based on the known aircraft's appearance and functionality. Based on this similarity, the basic structure of the target aircraft's load-bearing components, along with the mass ratios and distribution of various components, such as the structure, load, and fuel, are determined. By adjusting the cross-sectional form and material density, a finite element model of the relevant structure is established. Calculation and iteration are then used to determine the aircraft's inverse design structure, achieving inverse design of the aircraft structure through simulation, analysis, and comparison.

[0075] In S1, the known aircraft with the strongest structural configuration consistency with the design target aircraft is selected. The structural configuration includes the number and position of tail fins. Specifically, tail fin types include normal, canard, twin vertical tails, and tailless.

[0076] The number and position of the horizontal stabilizer. Specifically, the types of horizontal stabilizers include upper horizontal stabilizer, middle horizontal stabilizer, lower horizontal stabilizer, "T" horizontal stabilizer and high-mounted horizontal stabilizer;

[0077] The shape and position of the wings. Specifically, wing types include straight wings, swept wings, delta wings, low aspect ratio wings, high wings, mid wings, and low wings.

[0078] The location and number of engines. Specifically, the engines include single-engine and twin-engine, and the engine locations include fuselage installation, fuselage tail installation, wing lower installation, wing and tail root installation, and nacelle installation.

[0079] In S1, some other configuration aspects are also included, such as three-wing, flying wing, connecting wing, twin fuselage, canted wing and oblique wing, etc., to find the aircraft with the most structural configuration similarities with the design target aircraft.

[0080] In S2, when K1 in each direction is different, the wingspan ratio is used as a measure of the size ratio between the design target aircraft and the known aircraft.

[0081] In S3, please refer to Table 1 for the mass ratios of various parts of different types of aircraft:

[0082] parameter fighter Attack aircraft bomber Empty mass ratio 0.45～0.60 0.41～0.54 0.37～0.42 Fuel ratio 0.21～0.33 0.17～0.33 0.40～0.62 Effective load ratio 0.21～0.28 0.18～0.37 0.14～0.19 <![CDATA[Wing load (kgf / m 2 )]]> 262～467 315～544 447～516 Thrust-to-weight ratio (T / W) 0.65～1.26 0.56～0.88 0.26～0.40

[0083] Table 1 Mass ratio of various parts of different aircraft

[0084] If the design target aircraft is to be used after 2014, the lower limit of the empty-to-aircraft mass ratio for fighters can be 0.45 to 0.60, the lower limit of the empty-to-aircraft mass ratio for attack aircraft can be 0.41 to 0.54, and the lower limit of the empty-to-aircraft mass ratio for bombers can be 0.37 to 0.42.

[0085] The effective load ratio of fighters can be taken as the upper limit of 0.21 to 0.28, the effective load ratio of attack aircraft can be taken as the upper limit of 0.18 to 0.37, and the effective load ratio of bombers can be taken as the upper limit of 0.14 to 0.19;

[0086] The fuel ratio for fighters can be set at an upper limit of 0.21 to 0.33, the fuel ratio for attack aircraft can be set at an upper limit of 0.17 to 0.33, and the fuel ratio for bombers can be set at an upper limit of 0.40 to 0.62;

[0087] If the design target aircraft was used before 2000, the upper limit of the empty-to-mass ratio for fighters can be 0.45-0.60, the upper limit of the empty-to-mass ratio for attack aircraft can be 0.41-0.54, and the upper limit of the empty-to-mass ratio for bombers can be 0.37-0.42.

[0088] The effective load ratio for fighters can be taken as the lower limit of 0.21 to 0.28, the effective load ratio for attack aircraft can be taken as the lower limit of 0.18 to 0.37, and the effective load ratio for bombers can be taken as the lower limit of 0.14 to 0.19;

[0089] The fuel ratio of fighters can be taken as the lower limit of 0.21 to 0.33, the fuel ratio of attack aircraft can be taken as the lower limit of 0.17 to 0.33, and the fuel ratio of bombers can be taken as the lower limit of 0.40 to 0.62;

[0090] The total of the empty mass ratio, effective load ratio and fuel ratio is 100%.

[0091] In S4, when the main load-bearing structural materials of an aircraft are different, if a certain material is used for more than 90%, the density of that material shall prevail;

[0092] If a variety of materials are used, use the following formula to estimate the overall material density:

[0093]

[0094] Among them, ρ 总体 is the overall structural material density, ρ i is the material density of the i-th material, μ i is the mass percentage of the i-th material in the overall load-bearing structure.

[0095] In S5, it includes:

[0096] S5.1, adjust the structural quality;

[0097] If the modeling quality is higher than the target quality, the area of ​​the rib weight-reducing hole 3 is increased;

[0098] If the modeling quality is lower than the target quality, the area of ​​the rib weight-reducing hole 3 is reduced;

[0099] S5.2. Adjust the structure according to the structural bending frequency;

[0100] like Figure 1 As shown, if the bending frequency calculated during the simulation is too low, then while ensuring that the cross-section of the structure remains unchanged, the height of the beam structure is increased. In this embodiment, it specifically refers to the height b1 of the wing front beam 1 and the height b2 of the wing rear beam 2, while the width of the beam structure is reduced. Specifically, it refers to the width a1 of the wing front beam 1 and the width a2 of the wing rear beam 2.

[0101] If the bending frequency calculated during the simulation is too high, the height of the beam structure should be reduced and the width of the beam structure should be increased while ensuring that the cross-section of the structure remains unchanged.

[0102] S5.3. Adjust the structure according to the torsional bending frequency;

[0103] If the torsional frequency calculated during the simulation is too low, the distance c between the wing front beam 1 and the wing rear beam 2 is increased while ensuring that the cross section of the structure remains unchanged;

[0104] If the torsional frequency calculated during the simulation is too high, the distance c between the wing front beam 1 and the wing rear beam 2 is reduced while ensuring that the structural cross-section remains unchanged.

[0105] The aircraft structure inverse design method based on structural dynamics characteristics in the present invention adjusts the structural mass. If the modeled mass exceeds the target mass, the area of ​​the rib weight reduction holes 3 on the wing rib 4 is increased. The structure is then adjusted based on the structural bending frequency. If the bending frequency calculated during the simulation is too low, the heights (b1 and b2) of the wing front beam 1 and the wing rear beam 2 are increased, while the widths (a1 and a2) of the wing front beam 1 and the wing rear beam 2 are reduced, while the cross-section of the structure remains unchanged. Finally, the structure is adjusted based on the torsional bending frequency. If the torsional frequency calculated during the simulation is too low, the distance c between the wing front beam 1 and the wing rear beam 2 is increased, while the cross-section of the structure remains unchanged. If the opposite is true, the distance c between the wing front beam 1 and the wing rear beam 2 is changed accordingly.

[0106] In S6, isotropic materials should be used when establishing finite element models.

[0107] In S6, the established finite element model ignores components and structures with little influence on the structural mass and stiffness due to screws, connections, friction and gaps between structures.

[0108] In S6, the established finite element model can ignore the requirements and influences of the installation, disassembly, and relocation of the structure.

[0109] In S6, in order to facilitate calculation and simulation, the appearance of specific components can be appropriately simplified, and relatively simple geometric configurations can be used instead of complex structures.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for inverse design of aircraft structure based on structural dynamics characteristics, characterized in that: include: S1. Find a known aircraft that is similar to the target aircraft based on its appearance and function; S2. Calculate the mass parameters of the target aircraft using the similarity theory formula. The calculation formula is: Where K m is the mass ratio of the design target aircraft to the known aircraft, K1 is the size ratio of the design target aircraft to the known aircraft; S3. allocating the design target aircraft mass according to the specific functions of the aircraft and referring to relevant aircraft data; S4. Analyze the materials commonly used in this type of aircraft and determine the density of the corresponding parts of the materials; S5. Design the main load-bearing components, including wing spars, ribs, and fuselage frames, according to the basic structural form of this type of aircraft. Adjust the cross-sectional dimensions and spacing of each component so that the total mass of the aircraft structure is consistent with that obtained in S3 and the relative density of the structure is consistent with that obtained in S4. S6. Establish a corresponding finite element model, attach the fuel tank and load mass obtained in S3 to the relevant positions of the aircraft load-bearing components described in S5, perform corresponding finite element structural dynamics analysis, and compare the results with the structural dynamics characteristics of the design target aircraft; When the frequency error is higher than 5%, return to S5; When the frequency error is less than 5%, proceed to S7; S7. Locally adjust the distribution and structure of each part.

2. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S1, a known aircraft is selected that has the strongest structural configuration consistency with the design target aircraft, including the number and position of tail fins, the number and position of horizontal stabilizers, the shape and position of wings, and the position and number of engines.

3. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S2, when K1 in each direction is different, the wingspan ratio is used as a measure of the size ratio between the design target aircraft and the known aircraft.

4. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S3, If the design target aircraft is to be used after 2014, the lower limit of the empty-to-mass ratio for fighters is 0.45-0.60, the lower limit of the empty-to-mass ratio for attack aircraft is 0.40-0.54, and the lower limit of the empty-to-mass ratio for bombers is 0.37-0.

42. The upper limit of the effective load ratio for fighters is 0.21-0.28, the upper limit of the effective load ratio for attack aircraft is 0.18-0.37, and the upper limit of the effective load ratio for bombers is 0.14-0.

19. The fuel ratio for fighters is set at an upper limit of 0.21-0.33, the fuel ratio for attack aircraft is set at an upper limit of 0.17-0.33, and the fuel ratio for bombers is set at an upper limit of 0.40-0.62; If the design target aircraft was used before 2000, the upper limit of the empty-to-mass ratio for fighters is 0.45-0.60, the upper limit of the empty-to-mass ratio for attack aircraft is 0.40-0.54, and the upper limit of the empty-to-mass ratio for bombers is 0.37-0.

42. The effective load ratio for fighters is set at a lower limit of 0.21 to 0.28, the effective load ratio for attack aircraft is set at a lower limit of 0.18 to 0.37, and the effective load ratio for bombers is set at a lower limit of 0.14 to 0.

19. The fuel ratio for fighters is set at a lower limit of 0.21 to 0.33, the fuel ratio for attack aircraft is set at a lower limit of 0.17 to 0.33, and the fuel ratio for bombers is set at a lower limit of 0.40 to 0.

62. The total of the empty mass ratio, effective load ratio and fuel ratio is 100%.

5. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S4, when the main load-bearing structural materials of an aircraft are different, if a certain material is used for more than 90%, the density of that material shall prevail; If a variety of materials are used, use the following formula to estimate the overall material density: Among them, ρ 总体 is the overall structural material density, ρ i is the material density of the i-th material, μ i is the mass percentage of the i-th material in the overall load-bearing structure.

6. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S5, it includes: S5.1, adjust the structural quality; If the modeling quality is higher than the target quality, increase the area of ​​the rib weight-reducing holes; If the modeling quality is lower than the target quality, reduce the area of ​​the rib weight-reducing holes; S5.

2. Adjust the structure according to the structural bending frequency; If the bending frequency calculated during the simulation is too low, the height of the beam structure is increased while the width of the beam structure is reduced while ensuring that the cross-section of the structure remains unchanged. If the bending frequency calculated during the simulation is too high, the height of the beam structure should be reduced and the width of the beam structure should be increased while ensuring that the cross-section of the structure remains unchanged. S5.

3. Adjust the structure according to the torsional bending frequency; If the torsional frequency calculated during the simulation is too low, increase the distance between the front and rear wing beams while maintaining the same cross-section of the structure. If the torsional frequency calculated during the simulation is too high, the distance between the front and rear wing beams can be reduced while maintaining the structural cross-section.

7. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S6, isotropic materials should be used when establishing finite element models.

8. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S6, the established finite element model ignores components and structures with little influence on the structural mass and stiffness due to screws, connections, friction and gaps between structures.

9. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S6, the established finite element model ignores the requirements and influences of the installation, disassembly, and relocation of the structure.

10. The aircraft structure inverse design method based on structural dynamics characteristics according to claim 1, characterized in that: In S6, in order to facilitate calculation and simulation, the appearance of specific components is appropriately simplified, and relatively simple geometric configurations are used instead of complex structures.

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