Wing surface aerodynamic parameter dimension reduction method and device based on image processing

Abstract

The invention belongs to the technical field of aircraft aerodynamic load design, and particularly relates to a wing surface aerodynamic parameter dimension reduction method and device based on image processing, and the method comprises the steps: S1, dividing a wing surface into a plurality of data points with three-dimensional coordinates, and S2, dividing the data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set; s3, projecting the three-dimensional data point set of the upper surface and the three-dimensional data point set of the lower surface to a two-dimensional plane, and replacing the original xy with spanwise and chordwise coordinates; and S4, determining the position of the to-be-calculated aerodynamic load on the upper surface or the lower surface on the two-dimensional plane, interpolating the upper surface two-dimensional data point set or the lower surface two-dimensional data point set to the position of the to-be-calculated aerodynamic load on the two-dimensional plane to obtain a corresponding wing surface aerodynamic parameter, and further calculating to obtain the aerodynamic load at the corresponding position. According to the method, the upper surface and the lower surface are layered, three-dimensional calculation is converted into two-dimensional calculation, and the calculation dimension is reduced.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft aerodynamic load design, and in particular relates to a method and device for reducing the dimension of aerodynamic parameters of a wing surface based on image processing. Background Art

[0002] As computing power continues to increase, the numerical calculation accuracy of the aircraft surface flow field continues to improve. However, the data extracted from the numerical calculation results at specific positions on the wing surface needs to rely on numerical calculation post-processing software or other data processing software. It is very difficult to directly complete the three-dimensional interpolation required for flight load design based on the calculation grid point data. In addition, flight load calculations often require pressure data at specific spanwise and chordwise relative positions, and it is difficult to directly provide the absolute three-dimensional coordinates of the relative position. Therefore, direct aerodynamic data dimensionality reduction processing methods that do not rely on numerical analysis software can simplify the aerodynamic data extraction process for flight load design.

[0003] For any wing, as the trailing edge control surface of the wing deflects, the grid must be re-divided for interpolation, and the process requires the use of grid generation software and numerical analysis software, which makes it difficult to process data quickly and in batches. Summary of the invention

[0004] In order to solve the above problems, the present application provides a method for reducing the dimension of aerodynamic parameters of a wing surface based on image processing, comprising:

[0005] Step S1: dividing the wing surface into a number of data points, each data point including the three-dimensional coordinates of its location and the aerodynamic parameters of the wing surface at its location;

[0006] Step S2: dividing all data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set according to the wing upper surface and the wing lower surface according to the three-dimensional coordinates of the data points;

[0007] Step S3: projecting the upper surface three-dimensional data point set and the lower surface three-dimensional data point set onto the two-dimensional planes in the chord direction and the span direction respectively to obtain the upper surface two-dimensional data point set and the lower surface two-dimensional data point set;

[0008] Step S4: Determine the position of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane, interpolate the set of two-dimensional data points of the upper surface or the set of two-dimensional data points of the lower surface to the position of the aerodynamic load to be calculated on the two-dimensional plane to obtain the corresponding aerodynamic parameters of the wing surface, and then calculate the aerodynamic load at the corresponding position.

[0009] Preferably, the data point acquisition method includes:

[0010] Calculate the aerodynamic parameters of the wing surface using numerical calculation software;

[0011] The data points are obtained by deriving the three-dimensional coordinates of the wing surface calculation grid and the aerodynamic parameter results of the wing surface at the corresponding positions.

[0012] Preferably, step S2 specifically includes:

[0013] Step S21: Divide the wing surface into a plurality of wing segments along the span direction, and the data points of each wing segment are a set of calculated data points;

[0014] Step S22: sorting the data points of the calculated data point set according to the chord coordinates;

[0015] The data points whose chord coordinates are less than the first preset value are regarded as the front segment points.

[0016] The data point whose chord coordinate is greater than or equal to the first preset value and less than or equal to the second preset value is taken as the midpoint;

[0017] The data points whose chord coordinates are greater than the second preset value are taken as the latter points;

[0018] Step S23:

[0019] Among the front points, the front points whose vertical coordinates are greater than the wing leading edge line function are attributed to the upper surface, and the front points whose vertical coordinates are less than or equal to the leading edge line function are attributed to the lower surface;

[0020] Among the middle points, those with vertical coordinates greater than those of the previous points are assigned to the upper surface, and vice versa, to the lower surface;

[0021] For the rear point, substitute the vertical coordinates of the rear point into the following formula in order from small to large according to the chord coordinates to calculate the k value. When k is less than 1, the point belongs to the upper surface, otherwise, it belongs to the lower surface.

[0022]

[0023] Wherein, zup is the vertical coordinate of the previous distinguished rear segment point on the upper surface; zdown is the vertical coordinate of the previous distinguished rear segment point on the lower surface;

[0024] Step S24: the data points belonging to the lower surface are grouped into a lower surface three-dimensional data point set; the data points belonging to the upper surface are grouped into an upper surface three-dimensional data point set.

[0025] Preferably, the first preset value includes a preset first curvature value; and the second preset value includes a preset second curvature value.

[0026] Preferably, step S4 specifically includes:

[0027] Step S41: determining a target position (x0, y0) of the aerodynamic load to be calculated on the upper surface or the lower surface on a two-dimensional plane;

[0028] Step S42: draw a circle with the target position (x0, y0) as the center and r0 as the radius, and obtain data points within the circle;

[0029] Step S43: taking m data points closest to the position (x0, y0) from the data points within the circle as sample points, and interpolating the sample points to obtain the aerodynamic parameters of the wing surface at the target position (x0, y0).

[0030] Preferably, the aerodynamic parameters of the wing surface include a pressure coefficient Cp.

[0031] Preferably, the specific interpolation method of the pressure coefficient Cp is: i =sqrt((x i -x0) 2 +(y i -y0) 2 );

[0032] A device for reducing the dimension of aerodynamic parameters of a wing surface based on image processing, using the method for reducing the dimension of aerodynamic parameters of a wing surface based on image processing as described in the claims, comprising:

[0033] Loading module: used to divide the wing surface into a number of data points, each data point includes the three-dimensional coordinates of its location and the aerodynamic parameters of the wing surface at its location;

[0034] Division module: used for dividing all data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set according to the wing upper surface and the wing lower surface according to the 3D coordinates of the data points;

[0035] Projection module: used to project the upper surface three-dimensional data point set and the lower surface three-dimensional data point set onto the two-dimensional planes in the chord direction and the span direction respectively to obtain the upper surface two-dimensional data point set and the lower surface two-dimensional data point set;

[0036] Difference calculation module: used to determine the position of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane, interpolate the two-dimensional data point set of the upper surface or the two-dimensional data point set of the lower surface to the position of the aerodynamic load to be calculated on the two-dimensional plane to obtain the corresponding wing surface aerodynamic parameters, and then calculate the aerodynamic load at the corresponding position.

[0037] Preferably, the data point acquisition module comprises:

[0038] Calling unit: used to call numerical calculation software to calculate the aerodynamic parameter results of the wing surface;

[0039] Calculation unit: used for deriving the aerodynamic parameter results of the wing surface at the corresponding position from the three-dimensional coordinates of the wing surface calculation grid to obtain the data points.

[0040] Preferably, the division module specifically includes:

[0041] Wing segment segmentation unit: used to divide the wing surface into multiple wing segments along the span direction, and the data points of each wing segment are a set of calculation data points;

[0042] Sorting unit: used to sort the data points of the calculated data point set according to the chord coordinates;

[0043] The data points whose chord coordinates are less than the first preset value are regarded as the front segment points;

[0044] The data point whose chord coordinate is greater than or equal to the first preset value and less than or equal to the second preset value is taken as the midpoint;

[0045] The data points whose chord coordinates are greater than the second preset value are taken as the latter points;

[0046] Integration unit: used to integrate data points, specifically:

[0047] Among the front points, the points whose vertical coordinates are greater than the wing leading edge line function are attributed to the upper surface, and the front points whose vertical coordinates are less than or equal to the leading edge line function are attributed to the lower surface;

[0048] Among the middle points, those with vertical coordinates greater than those of the previous points are assigned to the upper surface, and vice versa, to the lower surface;

[0049] Among the middle points, the vertical coordinates of the rear points are substituted into the following formula in order from small to large according to the chord coordinates to calculate the k value. When k is less than 1, the point belongs to the upper surface, otherwise, it belongs to the lower surface.

[0050]

[0051] Wherein, zup is the vertical coordinate of the last segment point of the previous distinguished point in the upper surface; zdown is the vertical coordinate of the last segment point of the previous distinguished point in the lower surface; zi(l) is the vertical coordinate of the current point;

[0052] Collection module: used to collect data points belonging to the lower surface into a three-dimensional data point set for the lower surface; and to collect data points belonging to the upper surface into a three-dimensional data point set for the upper surface.

[0053] Preferably, the first preset value and the second preset value are both determined by the curvature of the wing surface.

[0054] Preferably, the difference calculation module specifically includes:

[0055] Target position determination unit: used to determine the target position (x0, y0) of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane;

[0056] Circular function delineation unit: draw a circle with the target position (x0, y0) as the center and r0 as the radius, and obtain the data points within the circle;

[0057] Circular function delineation unit: among the data points in the circle, the four data points closest to the position (x0, y0) are taken as sample points, and the sample points are interpolated to obtain the aerodynamic parameters of the wing surface at the target position (x0, y0).

[0058] Preferably, the aerodynamic parameters of the wing surface include but are not limited to the pressure coefficient Cp.

[0059] Preferably, it further includes an interpolation calculation module for interpolating and calculating the pressure coefficient Cp. The specific interpolation method is to calculate the distance between the target interpolation point and the four surrounding data points according to the following formula;

[0060] r i =sqrt((x i -x0) 2 +(y i -y0) 2 );

[0061] Among them, (x i ,y i ) is the position coordinate of the known numerical calculation point, and (x0, y0) is the target position coordinate.

[0062] Search the distance r from the target interpolation point based on the distance to the target interpolation point i Sort from small to large and select the four nearest points (x i ,y i ),i=1,2,3,4;

[0063] There is the following relationship between the four known data points on the upper or lower surface of the wing and the target point:

[0064]

[0065] in

[0066]

[0067] Where 1≤i≤4, 1≤j≤4, and i≠j

[0068] Cp=[000Cp1 Cp2 Cp3 Cp4] T

[0069] The unknown coefficient matrix C can be obtained by the following formula.

[0070] C=G -1 Cp

[0071] Furthermore, the value Cp0 of the aerodynamic parameter Cp at the target position (x0, y0) is:

[0072] Cp0=WC

[0073] Where W = [0x0 y0 b1 b2 b3 b4], where b i =r i 2 ln(r i 2 +0.001)

[0074] If det(G) = 0 or Cond(G) ≥ 10000, the parameters of the target point are obtained using the following formula:

[0075]

[0076] Where: Cp i is the aerodynamic parameter at the i-th point; Cp0 is the aerodynamic parameter at the target position (x0, y0).

[0077] Among them, (x i ,y i ) is the position coordinate of the known numerical calculation point, and (x0, y0) is the target position coordinate.

[0078] Search the distance r from the target interpolation point based on the distance to the target interpolation point i Sort from small to large and select the four nearest points (x i ,y i ),i=1,2,3,4;

[0079] There is the following relationship between the four known data points on the upper or lower surface of the wing and the target point:

[0080]

[0081] in

[0082]

[0083] Where 1≤i≤4, 1≤j≤4, and i≠j

[0084] Cp=[000Cp1 Cp2 Cp3 Cp4] T

[0085] The unknown coefficient matrix C can be obtained by the following formula.

[0086] C=G -1 Cp

[0087] Furthermore, the value Cp0 of the aerodynamic parameter Cp at the target position (x0, y0) is:

[0088] Cp0=WC

[0089] Where W = [0x0 y0 b1 b2 b3 b4], where b i =r i 2 ln(r i 2 +0.001)

[0090] If det(G) = 0 or Cond(G) ≥ 10000, the parameters of the target point are obtained using the following formula:

[0091]

[0092] Where: Cp i is the aerodynamic parameter at the i-th point; Cp0 is the aerodynamic parameter at the target position (x0, y0).

[0093] The advantages of this application include: adopting the upper and lower surface layering approach to convert three-dimensional calculations into two-dimensional calculations, reducing the calculation dimension and reducing the difficulty of calculations.

[0094] Designed spanwise and chordwise partitioning methods to accurately divide the three-dimensional coordinates on the aircraft wing into layers;

[0095] The interpolation method of the present application is used to accurately calculate the aerodynamic parameters of the target position, and then accurately calculate the aerodynamic load at the corresponding position. BRIEF DESCRIPTION OF THE DRAWINGS

[0096] Figure 1 This is a flow chart of a method for reducing the dimensionality of aerodynamic parameters of a wing surface based on image processing in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0097] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be further described in detail in detail and in detail in conjunction with the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments in the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0098] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installed", "connected", "connected" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection 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, an indirect connection through an intermediate medium, or the internal connection of two components. Technical personnel in the field can understand their specific meanings in this application according to the specific circumstances.

[0099] like Figure 1 The flowchart of the wing surface aerodynamic parameter dimension reduction method based on image processing is shown, including:

[0100] Step S1: Divide the wing surface into a number of data points, each data point includes the three-dimensional coordinates of its position and the aerodynamic parameters of the wing surface at its position; wherein, the data point calculates the aerodynamic parameter results of the wing surface through numerical calculation software; the three-dimensional coordinates of the wing surface calculation grid and the aerodynamic parameter results of the wing surface at the corresponding position are exported to obtain the data point; the data point is exported in the form of (x, y, z, Cp), x is the chord direction, y is the span direction, z is the vertical direction, and Cp is the aerodynamic parameter of the wing surface, specifically the pressure coefficient.

[0101] Step S2: dividing all data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set according to the wing upper surface and the wing lower surface according to the three-dimensional coordinates of the data points;

[0102] Step S3: projecting the upper surface three-dimensional data point set and the lower surface three-dimensional data point set onto the two-dimensional planes in the chord direction and the span direction respectively to obtain the upper surface two-dimensional data point set and the lower surface two-dimensional data point set;

[0103] Step S4: Determine the position of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane, interpolate the set of two-dimensional data points of the upper surface or the set of two-dimensional data points of the lower surface to the position of the aerodynamic load to be calculated on the two-dimensional plane to obtain the corresponding aerodynamic parameters of the wing surface, and then calculate the aerodynamic load at the corresponding position.

[0104] Preferably, step S2 specifically includes:

[0105] Step S21: Divide the wing surface into a plurality of wing segments along the span direction, and the data points of each wing segment are a set of calculated data points;

[0106] Step S22: sorting the data points of the calculated data point set according to the chord coordinates;

[0107] The data points whose chord coordinates are less than the first preset value are regarded as the front segment points.

[0108] The data point whose chord-wise coordinate is greater than or equal to the first preset value and less than or equal to the second preset value is taken as the midpoint;

[0109] The data points whose chord coordinates are greater than the second preset value are taken as the latter points;

[0110] Step S23:

[0111] Furthermore, the first 5% of all data points in step S22 may be the front section points of this wing segment. Considering that the wing may have an anhedral angle or geometric twist, according to each data point y i Coordinate inversion to find the theoretical front edge z coordinate z leading , in the aircraft body coordinate system, if the z coordinate of the data point is greater than z leading The points on the left and right sides belong to the upper surface, and vice versa, they belong to the lower surface.

[0112]

[0113] Among them, z=f(y) is the function relationship of the wing leading edge line.

[0114] Among the middle points, the middle points with vertical coordinates greater than the front points are classified as the upper surface, otherwise, they are classified as the lower surface; further, the first 5%-30% of all data points are the middle points, among which the data point with the smallest x in the entire wing segment (xi(1), yi(1), zi(1), Cpi(1)) is used as the reference point, and the points with z coordinates greater than zi(1) belong to the upper surface, otherwise, they belong to the lower surface.

[0115] For the rear point, substitute the vertical coordinates of the rear point into the following formula in order from small to large according to the chord coordinates to calculate the k value. When k is less than 1, the point belongs to the upper surface, otherwise, it belongs to the lower surface.

[0116]

[0117] Among them, zup is the vertical coordinate of the previous distinguished rear segment point in the upper surface; zdown is the vertical coordinate of the previous distinguished rear segment point in the lower surface; for example: assuming that there are a total of 100 points in a wing segment, first sort them by x coordinates, and distinguish the first 5%, that is, the first five points. For example, the first point is the upper surface and the second point is the lower surface. Then the first point is the first point in the upper surface set, and the second point is the first point in the lower surface set. And so on. If the judgment of the first 30% of the points is completed, there are 17 points in the upper surface set and 17 points in the lower surface set. There are 13 points in the set. At this time, zup is the 17th point and zdown is the 13th point. We can judge the 31st point based on this. Assuming that the 31st point belongs to the upper surface, there are 18 points in the upper surface set. The 18th point is the 31st point we just put in, and the lower surface set is still 13 points. Next, when judging the 32nd point, zup is the 18th point in the upper surface set, and zdown is still the 13th point in the lower surface set, that is, zup and zdown are constantly changing with the judgment process. There are n points in the set, and it is the nth one.

[0118] Step S24: the data points belonging to the lower surface are grouped into a lower surface three-dimensional data point set; the data points belonging to the upper surface are grouped into an upper surface three-dimensional data point set.

[0119] In step S3, all data points are projected onto the xoy plane, which can also be said to be the wing chord plane, and their relative coordinates are calculated according to their coordinates (x, y).

[0120]

[0121] S29, output the points on the upper and lower surfaces respectively according to (s, c, Cp) (where s and c are the relative coordinates in the span direction and the chord direction, respectively).

[0122] Preferably, the first preset value includes a preset first curvature value; the second preset value includes a preset second curvature value, and the first preset value is set to a, wherein a=(z2-z1) / (x2-x1);

[0123] The second preset value is set to b=(z3-z4) / (x3-x4), where (x1, z1), (x2, z2), (x3, z3), and (x4, z4) are four points at the same spanwise position on the upper surface or the lower surface respectively.

[0124] Preferably, step S4 specifically includes:

[0125] Step S41: determine the target position (x0, y0) of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane; sort from small to large according to the x coordinate;

[0126] Step S42: draw a circle with the target position (x0, y0) as the center and r0 as the radius, and obtain data points within the circle;

[0127]

[0128] Step S43: Select four data points closest to the position (x0, y0) from the data points within the circle as sample points, and interpolate the sample points to obtain the aerodynamic parameters of the wing surface at the target position (x0, y0).

[0129] Preferably, the aerodynamic parameters of the wing surface include a pressure coefficient Cp.

[0130] Preferably, r i =sqrt((x i -x0) 2 +(y i -y0) 2 );

[0131] Among them, (x i ,y i ) is the position coordinate of the known numerical calculation point, and (x0, y0) is the target position coordinate.

[0132] Search the distance r from the target interpolation point based on the distance to the target interpolation point i Sort from small to large and select the four nearest points (x i ,y i ),i=1,2,3,4;

[0133] There is the following relationship between the four known data points on the upper or lower surface of the wing and the target point:

[0134]

[0135] in

[0136]

[0137] Where 1≤i≤4, 1≤j≤4, and i≠j

[0138] Cp=[000Cp1 Cp2 Cp3 Cp4] T

[0139] The unknown coefficient matrix C can be obtained by the following formula.

[0140] C=G -1 Cp

[0141] Furthermore, the value Cp0 of the aerodynamic parameter Cp at the target position (x0, y0) is:

[0142] Cp0=WC

[0143] Where W = [0x0 y0 b1 b2 b3 b4], where b i =r i 2 ln(r i 2 +0.001)

[0144] If det(G) = 0 or Cond(G) ≥ 10000, the parameters of the target point are obtained using the following formula:

[0145]

[0146] Where: Cp i is the aerodynamic parameter at the i-th point; Cp0 is the aerodynamic parameter at the target position (x0, y0).

[0147] The advantages of this application include: adopting the upper and lower surface layering approach to convert three-dimensional calculations into two-dimensional calculations, reducing the calculation dimension and the difficulty of calculation;

[0148] Designed spanwise and chordwise partitioning methods to accurately divide the three-dimensional coordinates on the aircraft wing into layers;

[0149] The interpolation method of the present application is used to accurately calculate the aerodynamic parameters of the target position, and then accurately calculate the aerodynamic load at the corresponding position.

[0150] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A dimensionality reduction method for aerodynamic parameters of wing surface based on image processing, characterized in that: include: Step S1: dividing the wing surface into a number of data points, each data point including the three-dimensional coordinates of its location and the aerodynamic parameters of the wing surface at its location; Step S2: dividing all data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set according to the wing upper surface and the wing lower surface according to the three-dimensional coordinates of the data points; Step S3: projecting the upper surface three-dimensional data point set and the lower surface three-dimensional data point set onto the two-dimensional planes in the chord direction and the span direction respectively to obtain the upper surface two-dimensional data point set and the lower surface two-dimensional data point set; Step S4: Determine the position of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane, interpolate the set of two-dimensional data points of the upper surface or the set of two-dimensional data points of the lower surface to the position of the aerodynamic load to be calculated on the two-dimensional plane to obtain the corresponding aerodynamic parameters of the wing surface, and then calculate the aerodynamic load at the corresponding position.

2. The method for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 1, characterized in that: The data point acquisition method comprises: Calculate the aerodynamic parameters of the wing surface using numerical calculation software; The data points are obtained by deriving the three-dimensional coordinates of the wing surface calculation grid and the aerodynamic parameter results of the wing surface at the corresponding positions.

3. The wing surface aerodynamic parameter dimensionality reduction method based on image processing according to claim 1, characterized in that: Step S2 specifically includes: Step S21: Divide the wing surface into a plurality of wing segments along the span direction, and the data points of each wing segment are a set of calculated data points; Step S22: sorting the data points of the calculated data point set according to the chord coordinates; The data points whose chord coordinates are less than the first preset value are regarded as the front segment points; The data point whose chord coordinate is greater than or equal to the first preset value and less than or equal to the second preset value is taken as the midpoint; The data points whose chord coordinates are greater than the second preset value are taken as the latter points; Step S23: Among the front points, the points whose vertical coordinates are greater than the wing leading edge line function are attributed to the upper surface, and the front points whose vertical coordinates are less than or equal to the leading edge line function are attributed to the lower surface; Among the middle points, those with vertical coordinates greater than those of the previous points are assigned to the upper surface, and vice versa, to the lower surface; Among the middle points, the vertical coordinates of the rear points are substituted into the following formula in order from small to large according to the chord coordinates to calculate the k value. When k is less than 1, the point belongs to the upper surface, otherwise, it belongs to the lower surface. Wherein, zup is the vertical coordinate of the last segment point of the previous distinguished point in the upper surface; zdown is the vertical coordinate of the last segment point of the previous distinguished point in the lower surface; zi(l) is the vertical coordinate of the current point; Step S24: the data points belonging to the lower surface are grouped into a lower surface three-dimensional data point set; the data points belonging to the upper surface are grouped into an upper surface three-dimensional data point set.

4. The method for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 3, characterized in that: The first preset value and the second preset value are both determined by the curvature of the wing surface.

5. The method for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 3, characterized in that: Step S4 specifically includes: Step S41: determining a target position (x0, y0) of the aerodynamic load to be calculated on the upper surface or the lower surface on a two-dimensional plane; Step S42: draw a circle with the target position (x0, y0) as the center and r0 as the radius, and obtain data points within the circle; Step S43: Select four data points closest to the position (x0, y0) from the data points within the circle as sample points, and interpolate the sample points to obtain the aerodynamic parameters of the wing surface at the target position (x0, y0).

6. The method for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 5, characterized in that: The aerodynamic parameters of the wing surface include but are not limited to the pressure coefficient Cp.

7. The method for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 6, characterized in that: The specific interpolation method of the pressure coefficient Cp is to calculate the distance between the target interpolation point and the surrounding four data points according to the following formula; r i =sqrt((x i -x0) 2 +(y i -y0) 2 ); Among them, (x i ,y i ) is the position coordinate of the known numerical calculation point, and (x0, y0) is the target position coordinate. Search the distance r from the target interpolation point based on the distance to the target interpolation point i Sort from small to large and select the four nearest points (x i ,y i ),i=1,2,3,4; There is the following relationship between the four known data points on the upper or lower surface of the wing and the target point: in M Where 1≤i≤4, 1≤j≤4, and i≠j Cp=[0 0 0 Cp1 Cp2 Cp3 Cp4] T The unknown coefficient matrix C can be obtained by the following formula. C=G -1 Cp Furthermore, the value Cp0 of the aerodynamic parameter Cp at the target position (x0, y0) is: Cp0=WC Where W = [0 x0 y0 b1 b2 b3 b4], where If det(G) = 0 or Cond(G) ≥ 10000, the parameters of the target point are obtained using the following formula: Where: Cp i is the aerodynamic parameter at the i-th point; Cp0 is the aerodynamic parameter at the target position (x0, y0).

8. A device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing, characterized in that: The method for reducing the dimension of aerodynamic parameters of a wing surface based on image processing as described in claims 1 to 7 comprises: Loading module: used to divide the wing surface into a number of data points, each data point includes the three-dimensional coordinates of its location and the aerodynamic parameters of the wing surface at its location; Division module: used for dividing all data points into an upper surface three-dimensional data point set and a lower surface three-dimensional data point set according to the wing upper surface and the wing lower surface according to the 3D coordinates of the data points; Projection module: used to project the upper surface three-dimensional data point set and the lower surface three-dimensional data point set onto the two-dimensional planes in the chord direction and the span direction respectively to obtain the upper surface two-dimensional data point set and the lower surface two-dimensional data point set; Difference calculation module: used to determine the position of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane, interpolate the two-dimensional data point set of the upper surface or the two-dimensional data point set of the lower surface to the position of the aerodynamic load to be calculated on the two-dimensional plane to obtain the corresponding wing surface aerodynamic parameters, and then calculate the aerodynamic load at the corresponding position.

9. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 8, characterized in that: The data point acquisition module includes: Calling unit: used to call numerical calculation software to calculate the aerodynamic parameter results of the wing surface; Calculation unit: used for deriving the aerodynamic parameter results of the wing surface at the corresponding position from the three-dimensional coordinates of the wing surface calculation grid to obtain the data points.

10. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 8, characterized in that: The division modules include: Wing segment segmentation unit: used to divide the wing surface into multiple wing segments along the span direction, and the data points of each wing segment are a set of calculation data points; Sorting unit: used to sort the data points of the calculated data point set according to the chord coordinates; The data points whose chord coordinates are less than the first preset value are regarded as the front segment points; The data point whose chord coordinate is greater than or equal to the first preset value and less than or equal to the second preset value is taken as the midpoint; The data points whose chord coordinates are greater than the second preset value are taken as the latter points; Integration unit: used to integrate data points, specifically: Among the front points, the points whose vertical coordinates are greater than the wing leading edge line function are attributed to the upper surface, and the front points whose vertical coordinates are less than or equal to the leading edge line function are attributed to the lower surface; Among the middle points, those with vertical coordinates greater than those of the previous points are assigned to the upper surface, and vice versa, to the lower surface; Among the middle points, the vertical coordinates of the rear points are substituted into the following formula in order from small to large according to the chord coordinates to calculate the k value. When k is less than 1, the point belongs to the upper surface, otherwise, it belongs to the lower surface. Wherein, zup is the vertical coordinate of the last segment point of the previous distinguished point in the upper surface; zdown is the vertical coordinate of the last segment point of the previous distinguished point in the lower surface; zi(l) is the vertical coordinate of the current point; Collection module: used to collect data points belonging to the lower surface into a three-dimensional data point set for the lower surface; and to collect data points belonging to the upper surface into a three-dimensional data point set for the upper surface.

11. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 10, characterized in that: The first preset value and the second preset value are both determined by the curvature of the wing surface.

12. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 10, characterized in that: The difference calculation module specifically includes: Target position determination unit: used to determine the target position (x0, y0) of the aerodynamic load to be calculated on the upper surface or the lower surface on the two-dimensional plane; Circular function delineation unit: draw a circle with the target position (x0, y0) as the center and r0 as the radius, and obtain the data points within the circle; Circular function delineation unit: among the data points in the circle, the four data points closest to the position (x0, y0) are taken as sample points, and the sample points are interpolated to obtain the aerodynamic parameters of the wing surface at the target position (x0, y0).

13. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 12, characterized in that: The aerodynamic parameters of the wing surface include but are not limited to the pressure coefficient Cp.

14. The device for reducing dimensionality of aerodynamic parameters of wing surface based on image processing according to claim 13, characterized in that: It also includes an interpolation calculation module for interpolating and calculating the pressure coefficient Cp. The specific interpolation method is to calculate the distance between the target interpolation point and the four surrounding data points according to the following formula; r i =sqrt((x i -x0) 2 +(y i -y0) 2 ); Among them, (x i ,y i ) is the position coordinate of the known numerical calculation point, and (x0, y0) is the target position coordinate. Search the distance r from the target interpolation point based on the distance to the target interpolation point i Sort from small to large and select the four nearest points (x i ,y i ),i=1,2,3,4; There is the following relationship between the four known data points on the upper or lower surface of the wing and the target point: in M Where 1≤i≤4, 1≤j≤4, and i≠j Cp=[0 0 0 Cp1 Cp2 Cp3 Cp4] T The unknown coefficient matrix C can be obtained by the following formula. C=G -1 Cp Furthermore, the value Cp0 of the aerodynamic parameter Cp at the target position (x0, y0) is: Cp0=WC Where W = [0 x0 y0 b1 b2 b3 b4], where If det(G) = 0 or Cond(G) ≥ 10000, the parameters of the target point are obtained using the following formula: Where: Cp i is the aerodynamic parameter at the i-th point; Cp0 is the aerodynamic parameter at the target position (x0, y0).

Images