Design method of super / hypersonic natural laminar flow wing considering strong cross flow effect

Abstract

The design method of a super / hypersonic natural laminar wing considering strong cross-flow effect belongs to the field of aerodynamic shape design of aircraft. In order to improve the aerodynamic efficiency of super / hypersonic aircraft, the present invention designs the optimal target pressure distribution curve of the high Reynolds number and large swept wing of the super / hypersonic aircraft according to the initial super / hypersonic aircraft high Reynolds number and large swept wing section pressure distribution, and parametrically describes the airfoil in the wing. The airfoil of each section of the wing controls the wing geometry and performs parametric design of the airfoil based on the Hicks-Henne parameterization method; the amplitude and direction changes of the cross-flow velocity type are comprehensively adjusted by optimizing design means, the natural laminar range under high Mach number and high Reynolds number conditions are expanded, and the adaptability range and effect of the natural laminar design are improved. The present invention is applied to the design process of super / hypersonic natural laminar wings, which can improve the laminar range of the wing surface of the super / hypersonic aircraft and improve the aerodynamic efficiency of the super / hypersonic aircraft.

Description

Technical Field

[0001] The invention belongs to the field of aircraft aerodynamic shape design, and in particular relates to a design method for a super / hypersonic natural laminar flow wing taking into account strong cross flow effects. Background Art

[0002] Human beings have a constant pursuit of increasing the speed of transportation. With the development of global economic integration, super / hypersonic aircraft are an important development direction for future civil passenger aircraft, which can greatly shorten travel time for business and tourism, and improve the efficiency of global transportation operations. The lift-to-drag ratio of current aircraft under subsonic conditions can reach about 20.0, while the lift-to-drag ratio under supersonic conditions is only about 7.0, which shows that the aerodynamic efficiency of super / hypersonic aircraft is relatively low. When the aircraft is cruising at super / hypersonic speeds, the proportion of frictional resistance is relatively high (for example, under Mach number 2.0 conditions, frictional resistance can account for about 40% of the total resistance). Under the same Reynolds number, laminar frictional resistance is much smaller than turbulent frictional resistance (can be 90% lower), so the laminar design of super / hypersonic aircraft is an effective means to improve the aerodynamic efficiency of super / hypersonic aircraft.

[0003] For super / hypersonic aircraft, in order to obtain an aerodynamic configuration with lower wave resistance, the use of swept wings has become a consensus in the aerodynamic community; after years of accumulation, the large swept wing layout has become the basic configuration of super / hypersonic aircraft. For swept wings, the instability mechanism of the flow transition from laminar to turbulent is mainly attributed to four categories, namely leading edge line instability, cross-flow CF wave instability, streamwise TS wave instability and Görtler vortex instability. Under high Reynolds number and large sweep conditions, cross-flow instability is the main factor. The cross-flow instability is directly related to the amplitude of the cross-flow velocity pattern, so controlling the amplitude of the cross-flow velocity pattern will effectively increase the laminar range. Previous studies usually only reduce the amplitude of the cross-flow velocity pattern by regulating the cross-flow pressure gradient, but this method is not effective under strong cross-flow effects, and the laminar control effect is very limited. The present invention proposes a special target pressure distribution form and an optimization design method for realizing the target pressure distribution, which can comprehensively regulate the amplitude and direction of the cross-flow velocity pattern, greatly weaken the amplitude of the cross-flow velocity pattern by changing the direction of the cross-flow velocity, effectively increase the natural laminar flow range under the strong cross-flow effect, and improve the aerodynamic efficiency of super / hypersonic aircraft. Summary of the invention

[0004] The problem to be solved by the present invention is to improve the aerodynamic efficiency of a super / hypersonic aircraft, and a design method for a super / hypersonic natural laminar flow wing taking into account a strong cross flow effect is proposed.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions:

[0006] A design method for a super / hypersonic natural laminar flow wing considering strong cross flow effects comprises the following steps:

[0007] S1. Design the optimal target pressure distribution curve of the hypersonic / hypersonic aircraft with high Reynolds number and large swept wing according to the initial pressure distribution of the hypersonic / hypersonic aircraft with high Reynolds number and large swept wing section;

[0008] S2. parametrically describing the airfoil of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft obtained in step S1, controlling the wing geometry of each section airfoil of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft, and performing parametric design of the airfoil based on the Hicks-Henne parametric method;

[0009] S3. The airfoil obtained in step S2 is configured on a super / hypersonic aircraft with a high Reynolds number and a large swept wing, and a full-machine mesh is generated;

[0010] S4. The aircraft generated by the grid in step S3 is subjected to a CFD numerical simulation method to simulate the aerodynamic characteristics of a super / hypersonic aircraft, and a simulation result of the aerodynamic characteristics of a super / hypersonic aircraft is obtained;

[0011] S5. Extract the lift coefficient, drag coefficient, moment coefficient, and wing section pressure distribution of the hypersonic / hypersonic aircraft from the aerodynamic characteristics simulation results obtained in step S4; at the same time, extract the front and rear beam heights and maximum thickness of the airfoil of each wing section;

[0012] S6. setting the optimization target to the optimal target pressure distribution curve of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft and the drag coefficient of the entire aircraft of the hypersonic / hypersonic aircraft obtained in step S1, and setting the optimization constraints to the front and rear beam heights of the airfoils of each wing section, the maximum thickness of the airfoil, the lift coefficient of the wing, and the moment coefficient of the wing;

[0013] S7. Based on the proxy optimization algorithm, the optimization target set in step S6 is optimized, the airfoil parameterized design variables are adjusted through the proxy optimization algorithm, and steps S2-S6 are repeated until a super / hypersonic natural laminar wing considering strong cross flow effects is found that meets the optimization constraints and design requirements in step S6.

[0014] Furthermore, the specific implementation method of step S1 includes the following steps:

[0015] S1.1. Perform mesh generation and CFD aerodynamic characteristics evaluation on the initial super / hypersonic aircraft. The mesh generation is performed using the commercial software Pointwise, and the aerodynamic characteristics simulation is performed using the CFD solver ARI_CFD.

[0016] S1.2. Extract the initial super / hypersonic aircraft high Reynolds number and large swept wing profile pressure distribution, calculate the mean value of the pressure coefficient in the range of 0.2c~0.8c, and use it as the peak-to-peak pressure coefficient of the target pressure distribution suction peak. Set the suction peak position in the range of 0.005c~0.015c. After the suction peak, the pressure coefficient decreases by 0.01~0.02, and the chordwise position of the lowest point of the decrease is 0.01c~0.02c. Then, maintain the optimal target pressure distribution curve in an upward trend, and the slope of the upward part of the pressure distribution curve is less than 0.01 to generate the optimal target pressure distribution curve.

[0017] Furthermore, the specific implementation method of step S2 includes the following steps:

[0018] S2.1. Normalize the torsion angles of each control section and the coordinates of the upper and lower surfaces of the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing obtained in step S1;

[0019] S2.2. Then, the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing processed in step S2.1 is parametrically described, and the airfoil is parametrically designed based on the Hicks-Henne shape function method, and the expression is:

[0020] ;

[0021] ;

[0022] ;

[0023] ;

[0024] in, , are the ordinates of the upper and lower surfaces of the basic airfoil, respectively; is the perturbation function, and are the variables corresponding to the upper and lower surfaces of the i-th airfoil function respectively; is the peak position of the disturbance of the i-th airfoil function, is the chord coordinate, The chord coordinate Perturbation function, For the i The adjustment coefficient of the airfoil function.

[0025] Furthermore, the whole machine mesh generation process in step S3 is implemented by using a mesh deformation method based on radial basis function, and the expression of radial basis function is:

[0026] ;

[0027] ;

[0028] ;

[0029] in, is the interpolation function, The total number of radial basis functions used for the moving mesh, that is, the total number of object surface points participating in the moving mesh; is the weight coefficient sequence to be determined, which is determined by the object surface points participating in the moving grid; is the radial basis function, for Point and The Euclidean distance of the point, d is the radius of action of the dynamic grid, is the grid space point that needs to be deformed currently, The first point that currently affects the point that needs to be deformed i A surface point, is the radial distance ratio.

[0030] Furthermore, in step S5, the front and rear beam heights of each wing section airfoil are extracted to be the height at the position of 30%c and the height at the position of 70%c of each section airfoil.

[0031] Furthermore, the proxy optimization algorithm in step S7 is a strategy algorithm combining the Kriging model with the EI point adding criterion, the MSP point adding criterion, the LCB point adding criterion, and the PI point adding criterion.

[0032] Beneficial effects of the present invention:

[0033] The invention discloses a design method for a super / hypersonic natural laminar wing taking into account a strong cross-flow effect, and proposes a special target pressure distribution form and an optimization design method for achieving the target pressure distribution for a high Reynolds number and large swept wing of a super / hypersonic aircraft. By designing a super / hypersonic natural laminar wing taking into account a strong cross-flow effect, the laminar range of the wing surface during super / hypersonic cruising of the aircraft is increased, the cruising efficiency of the aircraft is improved, the range of the aircraft can be increased, the weight of the aircraft can be reduced, and the like.

[0034] The design method of a super / hypersonic natural laminar flow wing taking into account the strong cross flow effect described in the present invention is applied to the design process of a super / hypersonic natural laminar flow wing, which can increase the laminar flow range on the surface of a super / hypersonic aircraft wing and improve the aerodynamic efficiency of the super / hypersonic aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A flow chart of a design method for a super / hypersonic natural laminar flow wing taking into account a strong cross flow effect according to the present invention;

[0036] Figure 2Schematic diagram of the cross-flow / stream velocity profile of the super / hypersonic natural laminar flow wing of the present invention, wherein 1 is the swept wing surface, 2 is the stream velocity profile, 3 is the cross-flow velocity profile, and 4 is the wing surface streamline;

[0037] Figure 3 It is a schematic diagram of the optimal target pressure distribution curve for the high Reynolds number and large swept wing of the super / hypersonic aircraft described in the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the specific embodiments described are only part of the embodiments of the present invention, rather than all of the specific embodiments. The components of the specific embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations, and the present invention can also have other embodiments.

[0039] Therefore, the following detailed description of the specific embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents the selected specific embodiments of the present invention. Based on the specific embodiments of the present invention, all other specific embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0040] In order to further understand the content, features and effects of the present invention, the following specific implementation methods are given as examples, and the attached Figure 1 -Attached Figure 3 The detailed instructions are as follows: Specific implementation method one:

[0042] A design method for a super / hypersonic natural laminar flow wing considering strong cross flow effects comprises the following steps:

[0043] S1. Design the optimal target pressure distribution curve of the hypersonic / hypersonic aircraft with high Reynolds number and large swept wing according to the initial pressure distribution of the hypersonic / hypersonic aircraft with high Reynolds number and large swept wing section;

[0044] Furthermore, the specific implementation method of step S1 includes the following steps:

[0045] S1.1. Perform mesh generation and CFD aerodynamic characteristics evaluation on the initial super / hypersonic aircraft. The mesh generation is performed using the commercial software Pointwise, and the aerodynamic characteristics simulation is performed using the CFD solver ARI_CFD.

[0046] S1.2. Extract the initial super / hypersonic aircraft high Reynolds number and large swept wing profile pressure distribution, calculate the mean value of the pressure coefficient in the range of 0.2c~0.8c, and use it as the peak pressure coefficient of the suction peak of the target pressure distribution. Set the suction peak position in the range of 0.005c~0.015c. After the suction peak, the pressure coefficient decreases by 0.01~0.02, and the chord position of the lowest point of the decrease is 0.01c~0.02c. Then, keep the optimal target pressure distribution curve in an upward trend, and the slope of the upward part of the pressure distribution curve is less than 0.01, so as to generate the optimal target pressure distribution curve;

[0047] Further, the optimal target pressure distribution of the optimal target pressure distribution curve of the super / hypersonic aircraft with high Reynolds number and large swept wing designed in step S1 is within the range of 0.05c in the chord direction, and the shape of the optimal target pressure distribution curve is first rising to form a suction peak, the position of the suction peak is within the range of 0.005c~0.015c, and the value of the pressure coefficient at the suction peak is equal to the mean value of the pressure coefficient within the range of 0.2c~0.8c of the cross-sectional airfoil at the suction peak, and the pressure coefficient of the optimal target pressure distribution curve decreases by 0.01~0.02 after the suction peak, and the chord-wise position range of the lowest point of the decrease is 0.01c~0.02c; then the optimal target pressure distribution curve is maintained in an upward trend, and the slope of the curve is less than 0.01;

[0048] S2. parametrically describing the airfoil of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft obtained in step S1, controlling the wing geometry of each section airfoil of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft, and performing parametric design of the airfoil based on the Hicks-Henne parametric method;

[0049] Furthermore, the specific implementation method of step S2 includes the following steps:

[0050] S2.1. Normalize the torsion angles of each control section and the coordinates of the upper and lower surfaces of the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing obtained in step S1;

[0051] S2.2. Then, the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing processed in step S2.1 is parametrically described, and the airfoil is parametrically designed based on the Hicks-Henne shape function method, and the expression is:

[0052] ;

[0053] ;

[0054] ;

[0055] ;

[0056] in, , are the ordinates of the upper and lower surfaces of the basic airfoil, respectively; is the perturbation function, and are the variables corresponding to the upper and lower surfaces of the i-th airfoil function respectively; is the peak position of the disturbance of the i-th airfoil function, is the chord coordinate, The chord coordinate Perturbation function, For the i The adjustment coefficient of the airfoil function;

[0057] Furthermore, the disturbance peak position should be as close to the airfoil head as possible to improve the sensitivity of the airfoil head, expand the search range of the optimal design, and ensure better optimization effect;

[0058] S3. The airfoil obtained in step S2 is configured on a super / hypersonic aircraft with a high Reynolds number and a large swept wing, and a full-machine mesh is generated;

[0059] Furthermore, the whole machine mesh generation process in step S3 is implemented by using a mesh deformation method based on radial basis function, and the expression of radial basis function is:

[0060] ;

[0061] ;

[0062] ;

[0063] in, is the interpolation function, The total number of radial basis functions used for the moving mesh, that is, the total number of object surface points participating in the moving mesh; is the weight coefficient sequence to be determined, which is determined by the object surface points participating in the moving grid; is the radial basis function, for Point and The Euclidean distance of the point, d is the radius of action of the dynamic grid, is the grid space point that needs to be deformed currently, The first point that currently affects the point that needs to be deformed i A surface point, is the radial distance ratio;

[0064] Furthermore, the Wendland's C2 function used for mesh deformation is selected;

[0065] S4. The aircraft generated by the grid in step S3 is subjected to a CFD numerical simulation method to simulate the aerodynamic characteristics of a super / hypersonic aircraft, and a simulation result of the aerodynamic characteristics of a super / hypersonic aircraft is obtained;

[0066] S5. Extract the lift coefficient, drag coefficient, moment coefficient, and wing section pressure distribution of the hypersonic / hypersonic aircraft from the aerodynamic characteristics simulation results obtained in step S4; at the same time, extract the front and rear beam heights and maximum thickness of the airfoil of each wing section;

[0067] Further, in step S5, the front and rear beam heights of each wing section airfoil are extracted to be the height at the position of 30%c and the height at the position of 70%c of each section airfoil;

[0068] S6. setting the optimization target to the optimal target pressure distribution curve of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft and the drag coefficient of the entire aircraft of the hypersonic / hypersonic aircraft obtained in step S1, and setting the optimization constraints to the front and rear beam heights of the airfoils of each wing section, the maximum thickness of the airfoil, the lift coefficient of the wing, and the moment coefficient of the wing;

[0069] S7. Optimize the optimization target set in step S6 based on the proxy optimization algorithm, adjust the airfoil parameterized design variables through the proxy optimization algorithm, and repeat steps S2-S6 until a super / hypersonic natural laminar wing considering strong cross flow effect is found that meets the optimization constraints and design requirements in step S6;

[0070] Furthermore, the proxy optimization algorithm in step S7 is a strategy algorithm combining the Kriging model with the EI point adding criterion, the MSP point adding criterion, the LCB point adding criterion, and the PI point adding criterion.

[0071] Furthermore, the proxy optimization algorithm in S6 is a proxy optimization algorithm that combines the Kriging model and the EI+MSP+LCB+PI point adding strategy.

[0072] Furthermore, the Kriging model is an interpolation technique based on statistical theory that fully considers the spatial correlation characteristics of variables. The model predicted value at The expression is:

[0073] ;

[0074] in, is the unit column vector, for dimensional vector, is the estimated value of the regression model parameters, Two points in space and The related function of and All represent points in space;

[0075] matrix The expression is:

[0076] ;

[0077] ;

[0078] ;

[0079] ;

[0080] in, , is the kriging model parameter vector No. k The model shape and scope of applicability can be adjusted by using maximum likelihood estimation or optimization algorithms.

[0081] The EI point adding criterion is to improve the expected point adding criterion. The EI function is used as the learning function, and points are added at the position where the EI value takes the maximum value in the design space. The EI point adding model The expression is:

[0082] ;

[0083] ;

[0084] in, and is the minimum and maximum value of the variation range of each control parameter during the optimization process; is the model prediction value, is the current optimal value; Φ is the standard normal cumulative distribution function, ϕ is the probability density function of the standard normal distribution; is the standard deviation.

[0085] The MSP point adding criterion is to minimize the agent model point adding criterion. Its principle is to add points directly at the minimum value position predicted by the agent model, that is, the learning function is the agent model prediction value. The expression of the MSP point adding model is:

[0086] ;

[0087] in, and is the minimum and maximum value of the variation range of each control parameter during the optimization process; is the model's predicted value.

[0088] The LCB point adding criterion is the confidence lower bound point adding criterion, which uses both the predicted value and the error estimate to add points. The LCB point adding model The expression is:

[0089] ;

[0090] ;

[0091] in, and is the minimum and maximum value of the variation range of each control parameter during the optimization process; is the model prediction value, is the standard deviation, A It is an empirical parameter and may take different values ​​for different problems.

[0092] PI plus point criterion is to improve the probability plus point criterion, based on the model prediction value Relative to the current optimal value The improvement (PI) is the learning function, and a point is added at the position with the largest PI value in the design space. The expression of the point-adding model is:

[0093] ;

[0094] ;

[0095] in, and is the minimum and maximum value of the variation range of each control parameter during the optimization process; is the model prediction value, is the current optimal value; Φ is the standard normal cumulative distribution function; is the standard deviation.

[0096] The present embodiment describes a design method for a super / hypersonic natural laminar wing considering strong cross flow effects, with a Mach number of 2 and a Reynolds number of 1.6×10 7 Taking the natural laminar flow design process of supersonic aircraft wings as an example, the following optimal target pressure distribution curve method for designing high Reynolds number and large swept wings of super / hypersonic aircraft is given:

[0097] Firstly, according to the initial pressure distribution of each section of the supersonic aircraft wing, the optimal target pressure distribution that meets the working conditions is designed.

[0098] Furthermore, according to the initial supersonic aircraft wing section pressure distribution, designing the optimal target pressure distribution includes the following steps:

[0099] The mesh generation and CFD aerodynamic characteristics evaluation of the initial supersonic aircraft were carried out. The commercial software Pointwise was used for mesh generation, and the aerodynamic characteristics simulation was carried out using the self-developed CFD solver ARI_CFD of our unit.

[0100] The pressure distribution of the wing control section is extracted, and the mean value of the pressure coefficient in the range of 0.2c~0.8c is calculated as the peak-to-peak pressure coefficient of the suction peak of the target pressure distribution, with a value of 0.18, and the given suction peak position is 0.006c.

[0101] Given that the pressure coefficient drops by 0.015 after the suction peak, the chordwise position of the lowest point of the drop is 0.016c, and the slope of the rising part of the pressure distribution curve is determined to be 0.005, the optimal target pressure distribution curve is generated.

[0102] Furthermore, the aerodynamic characteristics of the entire aircraft (including wing components) were simulated using the CFD solver ARI_CFD.

[0103] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0104] Although the present application has been described above with reference to specific embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural conflict, the various features in the specific embodiments disclosed in the present application may be used in combination with each other in any manner, and the fact that these combinations are not exhaustively described in this specification is only for the sake of omitting space and saving resources. Therefore, the present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A design method for a super / hypersonic natural laminar flow wing considering strong cross flow effects, characterized in that: The steps include: S1. Design the optimal target pressure distribution curve of the hypersonic / hypersonic aircraft with high Reynolds number and large swept wing according to the initial super / hypersonic aircraft with high Reynolds number and large swept wing section pressure distribution; S2. parametrically describe the airfoil of the high Reynolds number and large swept wing of the super / hypersonic aircraft obtained in step S1, control the wing geometry of each section airfoil of the high Reynolds number and large swept wing of the super / hypersonic aircraft, and perform parametric design of the airfoil based on the Hicks-Henne parametric method; S3. The airfoil obtained in step S2 is configured on a super / hypersonic aircraft with a high Reynolds number and a large swept wing, and a full-machine mesh is generated; S4. The aircraft generated by the grid in step S3 is subjected to a CFD numerical simulation method to simulate the aerodynamic characteristics of a super / hypersonic aircraft, and a simulation result of the aerodynamic characteristics of a super / hypersonic aircraft is obtained; S5. Extract the lift coefficient, drag coefficient and moment coefficient of the hypersonic aircraft from the aerodynamic characteristics simulation results obtained in step S4, and extract the wing section pressure distribution; at the same time, extract the front and rear beam heights and the maximum thickness of the airfoil of each wing section; S6. Setting the optimization target as the optimal target pressure distribution curve of the high Reynolds number and large swept wing of the hypersonic / hypersonic aircraft and the drag coefficient of the entire aircraft of the hypersonic / hypersonic aircraft obtained in step S1, and setting the optimization constraints as the front and rear beam heights of the airfoils of each wing section, the maximum thickness of the airfoil, the lift coefficient of the wing, and the moment coefficient of the wing; S7. Based on the proxy optimization algorithm, the optimization target set in step S6 is optimized, the airfoil parameterized design variables are adjusted through the proxy optimization algorithm, and steps S2-S6 are repeated until a super / hypersonic natural laminar wing considering strong cross flow effects is found that meets the optimization constraints and design requirements in step S6.

2. The design method of a super / hypersonic natural laminar flow wing considering strong cross flow effect according to claim 1, characterized in that: The specific implementation method of step S1 includes the following steps: S1.

1. Perform mesh generation and CFD aerodynamic characteristics evaluation on the initial super / hypersonic aircraft. The mesh generation is performed using the commercial software Pointwise, and the aerodynamic characteristics simulation is performed using the CFD solver ARI_CFD. S1.

2. Extract the initial super / hypersonic aircraft high Reynolds number and large swept wing profile pressure distribution, calculate the average pressure coefficient in the range of 0.2c~0.8c, and use it as the peak-to-peak pressure coefficient of the target pressure distribution suction peak. Set the suction peak position in the range of 0.005c~0.015c. After the suction peak, the pressure coefficient decreases by 0.01~0.02, and the chordwise position of the lowest point of the decrease is 0.01c~0.02c. Then, maintain the optimal target pressure distribution curve in an upward trend, and the slope of the rising part of the pressure distribution curve is less than 0.01 to generate the optimal target pressure distribution curve.

3. The design method of a super / hypersonic natural laminar flow wing considering strong cross flow effect according to claim 2, characterized in that: The specific implementation method of step S2 includes the following steps: S2.

1. Normalize the torsion angles of each control section and the coordinates of the upper and lower surfaces of the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing obtained in step S1; S2.

2. Then, the airfoil of the super / hypersonic aircraft with high Reynolds number and large swept wing processed in step S2.1 is parametrically described, and the airfoil is parametrically designed based on the Hicks-Henne shape function method, and the expression is: e(i)=ln(0.5) / lnx i 0≤x i ≤1 in, are the ordinates of the upper and lower surfaces of the basic airfoil, respectively; f i is the perturbation function, a i and b i are the variables corresponding to the upper and lower surfaces of the i-th airfoil function; x i is the peak position of the disturbance of the ith airfoil function, x is the chord coordinate, f i (x) is the x disturbance function of the chord-wise coordinate, and e(i) is the adjustment coefficient of the i-th airfoil function.

4. The design method of a super / hypersonic natural laminar flow wing considering strong cross flow effect according to claim 3 is characterized in that: The whole machine mesh generation process in step S3 is implemented by using a mesh deformation method based on radial basis function. The expression of radial basis function is: Where F(r) is the interpolation function, n is the total number of radial basis functions used by the moving mesh, that is, the total number of object surface points involved in the moving mesh; w i is the weight coefficient sequence to be determined, which is determined by the object surface points participating in the moving grid; is the radial basis function, is point r and r i The Euclidean distance of the point, d is the radius of action of the dynamic grid, is the grid space point that needs to be deformed currently, is the i-th object surface point that currently affects the point that needs to be deformed, and η is the radial distance ratio.

5. The design method of a super / hypersonic natural laminar flow wing considering strong cross flow effect according to claim 4, characterized in that: In step S5, the front and rear beam heights of each wing section airfoil are extracted, which are the height at the position of 30%c and the height at the position of 70%c of each section airfoil.

6. The design method of a super / hypersonic natural laminar flow wing considering strong cross flow effect according to claim 5, characterized in that: The proxy optimization algorithm in step S7 is a strategy algorithm that combines the Kriging model with the EI point adding criterion, the MSP point adding criterion, the LCB point adding criterion, and the PI point adding criterion.

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