Aircraft structure inverse design method based on structural dynamics characteristics

Abstract

The invention relates to the technical field of aerospace engineering, in particular to an aircraft structure inverse design method based on structural dynamics characteristics. The aircraft structure inverse design method based on the structural dynamics characteristics comprises the following steps: firstly, finding an aircraft similar to a designed target aircraft according to the shape and the function of the known aircraft; according to the similarity relation, the basic structure of a force bearing part of the designed target aircraft and the mass ratio and the distribution position of the structure, the load, the fuel oil and other parts are given out. A finite element model of a related structure is established by adjusting the section form and the material density, and the inverse design structure of the aircraft is finally determined through calculation and iteration. The inverse design method preferentially meets structural dynamics similarity, is easier to meet and converge in the aspects of structural quality and rigidity design, reduces the number of times of iterative design, and has less requirements on aircraft design experience, so that the inverse design method has advantages in the case of insufficient aircraft design experience or in the inverse design process of some novel aircrafts.

Description

Technical Field

[0001] The invention relates to the technical field of aerospace engineering, 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 is only the aircraft shape, there is relatively little effective information, and the internal structure of the aircraft relies heavily on the designer's experience. The design often deviates greatly from the actual aircraft structure results.

[0005] (2) For some new aircraft structures, structural reverse 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 less aircraft design experience is required, it has advantages in areas where aircraft design experience is insufficient or in the inverse design process of 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 according to its appearance and function;

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

[0010] K m =K1 3

[0011] In the formula, 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 such aircraft and determine the density of the corresponding parts of the materials;

[0014] S5. Design the main load-bearing components including wing beams, ribs and fuselage frames according to the basic structural form of this type of aircraft, and 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, establishing a corresponding finite element model, attaching the fuel tank and load mass obtained in S3 to the relevant positions of the load-bearing components of the aircraft described in S5, performing corresponding finite element structural dynamics analysis, and comparing 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 consistency with the structural configuration of the design target aircraft, the structural configuration including the number and position of tail fins, the number and position of horizontal tails, 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 empty-aircraft mass ratio of fighter aircraft can be taken as the lower limit of 0.45-0.60, the empty-aircraft mass ratio of attack aircraft can be taken as the lower limit of 0.41-0.54, and the empty-aircraft mass ratio of bomber can be taken as the lower limit of 0.37-0.42;

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

[0025] If the design target aircraft is used before 2000, the upper limit of the empty-aircraft mass ratio of fighters can be 0.45-0.60, the upper limit of the empty-aircraft mass ratio of attack aircraft can be 0.41-0.54, and the upper limit of the empty-aircraft mass ratio of 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, effective load ratio and 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 more than one type of material is 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 ith 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 and 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 is reduced and the width of the beam structure is 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 torsion frequency calculated during the simulation is too low, increase the distance between the front and rear beams of the wing while keeping the cross section of the structure unchanged;

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

[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 effect on the quality and stiffness of the structure due to screws, connections, friction and gaps between 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 parts can be appropriately simplified, and relatively simple geometric configurations can be used to replace complex structures.

[0047] Beneficial effects:

[0048] The technical solution of the present invention first finds an aircraft similar to the design target aircraft based on the known aircraft shape 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. The finite element model of the relevant structure is established by adjusting the cross-sectional form and material density, and then the inverse design structure of the aircraft is finally determined through calculation and iteration, and the inverse design of the aircraft structure is realized through the method of simulation analysis and comparison.

[0049] The technical solution of the present invention increases the design input, takes the known aircraft shape and structural dynamic characteristics (modal frequency and modal vibration shape of the aircraft) as input variables, obtains the specific internal structure of the design target aircraft, and makes the structural inverse design result more accurate;

[0050] The results of the 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 implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

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

[0054] Figure 2 It is a flow chart of the reverse design method in the present invention;

[0055] Figure 3 It is a schematic diagram of the wing structure of the reverse design method in the present invention.

[0056] Description of reference numerals:

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

[0058] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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 indicate orientations or positional relationships based on the orientations 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 referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0060] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the 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 indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to 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 according to its appearance and function;

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

[0064] K m =K1 3

[0065] In the formula, 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 such aircraft and determine the density of the corresponding parts of the materials;

[0068] S5. Design the main load-bearing components including wing beams, ribs and fuselage frames according to the basic structural form of this type of aircraft, and 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, establishing a corresponding finite element model, attaching the fuel tank and load mass obtained in S3 to the relevant positions of the load-bearing components of the aircraft described in S5, performing corresponding finite element structural dynamics analysis, and comparing 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 for obtaining the specific internal structure of the aircraft using the aircraft shape and structural dynamic characteristics (modal frequencies and modal vibration shapes of the aircraft) as input variables.

[0074] The technical solution of the present invention first finds an aircraft similar to the design target aircraft based on the known aircraft shape 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. The finite element model of the relevant structure is established by adjusting the cross-sectional form and material density, and then the inverse design structure of the aircraft is finally determined through calculation and iteration, and the inverse design of the aircraft structure is realized through the method of simulation analysis and comparison.

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

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

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

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

[0079] In S1, some other configuration aspects are also included, such as three-wing, flying wing, connected wing, twin fuselage, forward 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 different aircraft parts

[0084] If the design target aircraft is to be used after 2014, the empty-aircraft mass ratio of fighter aircraft can be taken as the lower limit of 0.45-0.60, the empty-aircraft mass ratio of attack aircraft can be taken as the lower limit of 0.41-0.54, and the empty-aircraft mass ratio of bomber can be taken as the lower limit of 0.37-0.42;

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

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

[0088] 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;

[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 the aircraft are different, if a certain material is used for more than 90%, the density of the material shall prevail;

[0092] If more than one type of material is 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 ith 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 the height of the beam structure is increased while ensuring that the cross section of the structure remains unchanged. 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 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 is reduced and the width of the beam structure is 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 torsion 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 torsion 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 dynamic characteristics in the present invention adjusts the structural mass. If the modeling mass is higher than the target mass, the area of ​​the rib weight reduction hole 3 on the wing rib 4 is increased. Then the structure is adjusted according to the structural bending frequency. If the bending frequency calculated during the simulation is low, the height (b1 and b2) of the wing front beam 1 and the wing rear beam 2 is increased while the width (a1 and a2) of the wing front beam 1 and the wing rear beam 2 is reduced while the cross section of the structure remains unchanged. Finally, the structure is adjusted according to the torsion bending frequency. If the torsion frequency calculated during the simulation is 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 it is the opposite to the above situation, the corresponding change is made.

[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 that have little effect 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 on the structure.

[0109] In S6, in order to facilitate calculation and simulation, the appearance of specific parts can be appropriately simplified, and relatively simple geometric configurations can be used to replace 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by 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 according to its appearance and function; S2. Calculate the mass parameters of the target aircraft according to the similarity theory formula. The calculation formula is: K m =K1 3 In the formula, 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 such aircraft and determine the density of the corresponding parts of the materials; S5. Design the main load-bearing components including wing beams, ribs and fuselage frames according to the basic structural form of this type of aircraft, and 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, establishing a corresponding finite element model, attaching the fuel tank and load mass obtained in S3 to the relevant positions of the load-bearing components of the aircraft described in S5, performing corresponding finite element structural dynamics analysis, and comparing 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 is characterized in that: In S1, a known aircraft is selected that has the strongest consistency with the design target aircraft in terms of structural configuration, including the number and position of tail fins, the number and position of horizontal tails, 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 empty-aircraft mass ratio of fighter aircraft can be taken as the lower limit of 0.45-0.60, the empty-aircraft mass ratio of attack aircraft can be taken as the lower limit of 0.40-0.54, and the empty-aircraft mass ratio of bomber can be taken as the lower limit of 0.37-0.42; 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; The fuel ratio of fighters can be taken as the upper limit of 0.21 to 0.33, the fuel ratio of attack aircraft can be taken as the upper limit of 0.17 to 0.33, and the fuel ratio of bombers can be taken as the upper limit of 0.40 to 0.62; If the design target aircraft is used before 2000, the upper limit of the empty-aircraft mass ratio of fighters can be 0.45-0.60, the upper limit of the empty-aircraft mass ratio of attack aircraft can be 0.40-0.54, and the upper limit of the empty-aircraft mass ratio of bombers can be 0.37-0.42; 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; 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; 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 the aircraft are different, if a certain material is used for more than 90%, the density of the material shall prevail; If more than one type of material is 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 ith 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 and 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 is reduced and the width of the beam structure is 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 torsion frequency calculated during the simulation is too low, increase the distance between the front and rear beams of the wing while keeping the cross section of the structure unchanged; If the torsional frequency calculated during the simulation is too high, the distance between the front and rear wing beams is reduced while ensuring that the structural cross-section remains unchanged.

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 that have little effect 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 can ignore the requirements and influences of the installation, disassembly, and relocation of the structure on 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 parts can be appropriately simplified, and relatively simple geometric configurations can be used to replace complex structures.

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