A method and system for auxiliary design of ultra-compact air intake profile

Abstract

The present invention belongs to the technical field of air intake duct structure design, and discloses an ultra-compact air intake duct profile auxiliary design method and system. The present invention can not only realize the generation of discrete information of the overall structure of the air intake duct and the display of various key geometric characteristic curves and partial geometric characteristic parameter values ​​by importing a custom model file containing various parameter values ​​of the air intake duct or editing and inputting various parameter values ​​of the air intake duct, but also can quickly realize the simple dynamic display of the three-dimensional model of the air intake duct with auxiliary observation function and the generation of point cloud coordinate files, and on this basis, realize a specific triangulation method without point cloud denoising and generate a three-dimensional file containing triangulation information for the spatial structural characteristics of the point cloud coordinates, further realize the high-quality dynamic display of the air intake duct profile model with auxiliary observation function, thereby realizing the ultra-compact air intake duct profile structure design.

Description

Technical Field

[0001] The invention belongs to the technical field of ultra-compact air intake duct profile structure design, and in particular relates to an ultra-compact air intake duct profile auxiliary design method and system. Background Art

[0002] The air inlet is an important component of air-breathing aircraft. It is located at the front end of the entire propulsion system and has many functions such as capturing and regulating air flow, converting and utilizing incoming kinetic energy, adjusting the size and uniformity of engine inlet flow velocity, and isolating upstream and downstream disturbances. It has a direct impact on the working efficiency and envelope of the propulsion system.

[0003] Characterized by the shape of the inlet cross section, including quasi-triangle, quasi-trapezoidal and slit-shaped, the corresponding aircraft have obvious differences in functional positioning and flight conditions. In addition, characterized by the compactness of the inlet, the ultra-compact inlet can reduce material consumption, reduce the empty weight of the aircraft, and thus reduce the cost of the entire life cycle of the aircraft.

[0004] Therefore, in order to take into account the overall functional positioning and implementation requirements of the aircraft, the design of the air inlet is particularly important. The existing more conventional air inlet design method is to first design a three-dimensional model through computer-aided design software (CAD), and then use computational fluid dynamics (CFD) software to perform flow field analysis of the pipeline. However, the method of designing the three-dimensional model of the aircraft air inlet using the existing general CAD software has the problems of difficult parameter control and poor functional targeting.

[0005] At present, there are few dedicated air intake design auxiliary software. There are two main reasons: 1. The development of air intake design auxiliary software involves the cross-research of aviation and computer science, which requires professionals to have a complex understanding of both fields; 2. The air intake design process is complex, with many types and parameters of air intakes, and it is necessary to display, analyze and visualize a variety of intermediate results, which increases the technical difficulty. It can be seen that the existing technology needs to be further improved. Summary of the invention

[0006] The purpose of the present invention is to propose an ultra-compact air intake duct profile auxiliary design method to achieve ultra-compact air intake duct profile structure design with parameter control and three-dimensional visualization.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme:

[0008] An ultra-compact air inlet profile auxiliary design method comprises the following steps:

[0009] Step 1. Edit and control the various parameter values ​​of the inlet profile on the UI interface by importing the custom model file mode or the self-design mode. After the values ​​of various parameters are confirmed, the discrete information of the three-dimensional model of the inlet profile is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and partial geometric feature parameter values ​​are displayed on the UI interface;

[0010] Step 2. Based on the spatial characteristics of the discrete information of the three-dimensional model of the air intake surface generated in step 1, a simple dynamic display of the three-dimensional model of the air intake surface with an auxiliary observation function is realized based on the method of drawing quadrilateral primitives in the open graphics library OpenGL, including the display of the air intake symmetry surface and the air intake grid effect and the generation of a point cloud coordinate file of the model;

[0011] Step 3. Based on the spatial features of the point cloud information of the three-dimensional model of the air inlet surface generated in step 2, generate triangular mesh information according to the triangular meshing method and save the relevant three-dimensional format file, and use OpenGL to achieve high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function.

[0012] In addition, based on the above-mentioned ultra-compact air intake duct profile auxiliary design method, the present invention also proposes a corresponding ultra-compact air intake duct profile auxiliary design system, and its scheme is as follows:

[0013] An ultra-compact air intake profile auxiliary design system, comprising:

[0014] The air intake duct profile design module is used to edit and control the various parameter values ​​of the air intake duct profile on the UI interface by importing a custom model file mode or a self-design mode. After the values ​​of various parameters are confirmed, the discrete information of the three-dimensional model of the air intake duct profile is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and partial geometric feature parameter values ​​are displayed on the UI interface;

[0015] A simple 3D dynamic display module is used to realize the simple dynamic display of the 3D model of the air intake profile generated by the air intake profile design module based on the spatial characteristics of the discrete information of the 3D model of the air intake profile. The module can be used to display the symmetry surface of the air intake and the mesh effect of the air intake, and to generate the point cloud coordinate file of the model.

[0016] As well as a high-quality dynamic three-dimensional display module, it is used to generate triangular mesh information and save related three-dimensional format files based on the spatial characteristics of the point cloud information of the three-dimensional model of the air inlet surface generated by the simple three-dimensional dynamic display module, and realize high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function through OpenGL.

[0017] The present invention has the following advantages:

[0018] As described above, the present invention relates to an ultra-compact air intake duct surface auxiliary design method and system, which is used to realize the ultra-compact air intake duct surface structure design with parameter control and three-dimensional visualization. The present invention can not only realize the generation of discrete information of the overall structure of the air intake duct and the display of various key geometric characteristic curves and partial geometric characteristic parameter values ​​by importing a custom model file containing various parameter values ​​of the air intake duct or editing and inputting various parameter values ​​of the air intake duct, but also can quickly realize the simple dynamic display of the air intake duct three-dimensional model with auxiliary observation function and the generation of point cloud coordinate files. On this basis, according to the spatial structure characteristics of the point cloud coordinates, a specific triangular meshing algorithm without point cloud denoising is realized and a three-dimensional file containing triangular mesh information is generated, and further high-quality dynamic display of the air intake duct surface model with auxiliary observation function is realized, so that the ultra-compact air intake duct surface design has the effect of parameter controllable and three-dimensional display, which is of great significance to assisting air intake duct designers in designing the air intake duct surface structure and quickly feeding back the visual design results of the model. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart of the auxiliary design method of the ultra-compact air inlet profile in an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of drawing a quadrilateral in an embodiment of the present invention.

[0021] Figure 3 A schematic diagram of constructing a triangular mesh in an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0023] This embodiment describes an ultra-compact air intake duct profile auxiliary design method, which is implemented based on the Windows Form desktop application development framework in the C# programming language development platform to achieve ultra-compact air intake duct profile structure design with parameter control and three-dimensional visualization.

[0024] like Figure 1 As shown, the ultra-compact air inlet profile auxiliary design method specifically includes the following steps:

[0025] Step 1. Edit and control the parameter values ​​of the inlet profile on the UI interface by importing the custom model file mode or the self-design mode. After the parameter values ​​are confirmed, the discrete information of the three-dimensional model of the inlet profile is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and some geometric feature parameter values ​​are displayed on the UI interface.

[0026] The custom model file is a custom model file containing various parameters of the inlet duct profile. The suffix of the custom model file is par. The content format of the custom model file includes the following in order:

[0027] The cross-sectional entity discrete information required for the inlet surface model is in the form of:

[0028] The position index of the cross-section entity in the custom model file, a single-line mixed description of the cross-section shape in text and parameter values, and N two-dimensional coordinate values ​​obtained after uniform discretization of the cross-section edge line, each coordinate represents the coordinate of a point on the edge line on the two-dimensional plane;

[0029] The entity discrete information of the change law required by the inlet surface model is in the form of:

[0030] The bit index of the change law entity in the custom model file, a single-line mixed description of the change law curve shape in text and parameter values, and N two-dimensional coordinate values ​​obtained after uniform discretization of the change law curve, each coordinate represents the coordinate of a point on the change law curve on the two-dimensional plane;

[0031] The various parameter values ​​of the inlet surface model, including overall constraint parameter values ​​and geometric design parameter values.

[0032] In step 1, the process of displaying and editing the parameters of the inlet profile is as follows:

[0033] When the system is in the mode of importing custom model files, the process of displaying and editing the parameters of the air intake profile on the UI interface is as follows:

[0034] Read the parameter values ​​of the air inlet profile in the custom model file line by line;

[0035] For non-section and changing parameter values, including the inlet area, outlet area, area expansion ratio, axial length, longitudinal offset, lateral offset, middle section width ratio, width and height control coefficient and section smoothing control mode, the Text property of the data display box TextBox is used to receive them. When the parameter value needs to be modified, edit the value in the data display box and trigger the TextChange() function to update the parameter value in the background.

[0036] For cross-sections and change laws, parse the corresponding single-line mixed description information in the custom model file, display all cross-section entities and change law entities in the UI interface, and set various key cross-sections and change laws according to the parameter values ​​in the custom model file and their positional index in the file.

[0037] Based on the ScottPlot interactive drawing library under the Windows Form platform, two FormsPlot coordinate graph controls are established in the UI interface to facilitate the display of cross-sectional shapes and change law curves.

[0038] When the system imports a custom model file and reads it or creates it by itself, the setup function is called.

[0039] Set the function as follows: load the FormsPlot coordinate graph display interface and the drawing curve drawing animation, set the title of the coordinate graph and the color of the curve, and bind the coordinate values ​​of the cross section or change law to the preset X-axis and Y-axis respectively.

[0040] According to the currently selected section or change rule, use AddScatterLines() to set the corresponding edge line coordinates or curve coordinates as the curve coordinates in the FormPlot coordinate diagram.

[0041] When different sections and change rules are selected, use Clear() to clear the curve data in the FormPlot control, and use AddScatterLines() to add the coordinate information of the currently selected section or change rule to redraw the curve.

[0042] When the system is in self-design mode, the process of displaying and editing the parameters of the air intake profile on the UI interface is as follows:

[0043] For non-section and variation law parameter values, the Text property of the data display box TextBook is used to receive the parameter values ​​edited and input by the user, and they are updated synchronously the next time the inlet profile is generated; for the required section, select the classic section shape provided by the system, and modify the corresponding shape parameter values ​​to create a specific section entity; for the required variation law, select the classic variation law provided by the system, and modify the corresponding curve parameter values ​​to create a specific variation law entity.

[0044] According to the created section entity, the key sections (inlet inlet section, middle 1 transition section, middle 2 transition section and outlet section) are set respectively; according to the created change law entity, the lateral change law of the centerline of the inlet duct and the area change law are set respectively.

[0045] In the self-design mode, use the FormsPlot control in the ScottPlot interactive drawing library to display the created cross-sectional shape and change law curve.

[0046] In step 1, the discrete information of the three-dimensional model of the air inlet profile is generated and the curve graphs of various key geometric characteristic parameters and the display process of some geometric characteristic parameter values ​​are as follows:

[0047] After confirming the various parameters of the inlet duct profile, the discrete data of the M intermediate transition section edge lines of the inlet duct profile are generated based on the curvature-controlled cross-sectional shape transition generation method. The intermediate transition sections are evenly distributed along the direction perpendicular to the center line of the inlet duct, and the center line passes vertically through the center point of each section.

[0048] Each intermediate transition section edge profile is composed of N discrete points; a two-dimensional array of M rows and N columns in the C# programming language is used to temporarily store the coordinates of M*N discrete points, wherein M and N are both natural numbers greater than 0.

[0049] According to the temporarily stored discrete data of the inlet profile, that is, M*N discrete point coordinates, 6 FormsPlot coordinate graphs for displaying the curves of various key geometric characteristic parameters are established on the UI interface.

[0050] The title of the first coordinate graph is Center Line and Upper and Lower Wall Profiles, which is used to display the curves of the center line and upper and lower wall profiles of the air inlet.

[0051] The title of the second coordinate graph is Area Change Law, which is used to display the trend curve of the area changes of all intermediate transition sections of the inlet duct.

[0052] The title of the third coordinate graph is Centerline Variation Law, which is used to display the distribution trend curve of the center points of all intermediate transition sections of the inlet duct along the lateral length of the inlet duct.

[0053] The title of the fourth coordinate graph is Inlet Section, Middle Section 1, Middle Section 2 and Outlet Section Shape, which is used to display the two-dimensional shape curves of these four sections of the inlet duct.

[0054] The title of the fifth coordinate graph is Inlet Section, Middle Section 1, Middle Section 2 and Exit Section Curvature, which is used to display the curvature distribution curves of the shape curves of these four sections of the inlet duct.

[0055] The title of the sixth coordinate graph is "Height and Width Regularity Curve", which is used to display the distribution trend curve of the height and width of the air intake duct.

[0056] According to the temporarily stored discrete data of the inlet surface, some geometric features of the inlet surface are calculated, including the maximum curvature of the upper wall, the maximum curvature of the centerline, the maximum curvature of the lower wall, the maximum width / total length, the maximum height / total length and the length / exit circle diameter. Corresponding TextBox controls are added to the UI interface to display the corresponding geometric feature parameter values.

[0057] When the intake duct profile design is completed and needs to be saved, the parameters of the profile are saved in a custom model file.

[0058] Step 2. Based on the spatial characteristics of the discrete information of the three-dimensional model of the air inlet surface generated in step 1, a simple dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function is quickly realized based on the method of drawing quadrilateral primitives in the open graphics library OpenGL, including the display of the air inlet symmetry surface and the air inlet grid effect and the generation of the point cloud coordinate file of the model.

[0059] In step 2, the process of simple dynamic display of the three-dimensional model of the air intake profile with auxiliary observation function is as follows:

[0060] Create an OpenGLControl control in the UI interface to display the 3D model drawn by OpenGL.

[0061] Using the structural characteristics of the discrete information of the three-dimensional model of the inlet profile temporarily stored in the two-dimensional array of M rows and N columns in step 1, such as Figure 2 As shown, P(n,m) represents the mth point on the edge profile of the nth middle section, n=1,2,…,N, m=1,2,…,M.

[0062] For the adjacent middle sections n and n+1, first connect the points of the same order on the two sections in sequence, such as P(n,i) and P(n+1,i), P(n,i+1) and P(n+1,i+1) and subsequent points, and then connect the adjacent points on the edge profile of a single section in sequence, such as P(n,i) and P(n,i+1), P(n,i+1) and P(n,i+2) and subsequent points.

[0063] Based on the method of constructing quadrilateral primitives in OpenGL, a quadrilateral with four vertices P(n,i), P(n+1,i), P(n,i+1) and P(n+1,i+1) is taken as an example as a primitive.

[0064] By analogy, the entire air intake profile can be drawn with (N-1)*M adjacent quadrilaterals, and each quadrilateral is filled with a custom color, thereby achieving a complete air intake profile display effect in the OpenGLControl control.

[0065] For auxiliary observation functions, the system provides a Button control for displaying the left section of the inlet profile, a Button control for displaying the right section of the inlet profile, and a Button for displaying the grid effect of the inlet profile.

[0066] The click() function is triggered by clicking the corresponding button, and the OpenGL drawing function is adjusted to achieve the corresponding display effect.

[0067] For the dynamic transition effect display of the air intake surface, the NumericUpDown digital increase and decrease control is used to bind the total number of sections K involved in constructing the quadrilateral primitive, that is, the first K sections are used to construct the quadrilateral primitive, K≤M.

[0068] When the K value in the NumericUpDown control is modified, the intake duct profile in the OpenGLControl control will only transition and display to the Kth section. Use the NumericUpDown control to control the K value to increase from 0 to M, which fully displays the dynamic transition effect of the overall intake duct profile.

[0069] In step 2, the process of generating the point cloud coordinate file of the inlet surface model is as follows:

[0070] Using the discrete information of the intake duct surface structure temporarily stored in the two-dimensional array of M rows and N columns in step 1, create a txt format file named "overall point cloud file without structure information" and traverse the two-dimensional array of M rows and N columns.

[0071] Each time a coordinate element is traversed, the x-axis coordinate value, y-axis coordinate value, and z-axis coordinate value of the coordinate are added to the next line in the txt format file, separated by spaces, until the traversal is completed. There are a total of M*N lines of coordinate information in the txt format file.

[0072] Step 3. Based on the spatial characteristics of the point cloud information of the three-dimensional model of the air inlet surface generated in step 2, according to the customized triangulated meshing method, the triangulated mesh information can be generated and the relevant three-dimensional format file can be saved without point cloud denoising, and high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function can be achieved through OpenGL.

[0073] In step 3, the process of using the triangular meshing method to generate the triangular mesh information of the surface is as follows:

[0074] For the point cloud information of the three-dimensional model of the air inlet profile generated in step 2, the air inlet profile is composed of M intermediate sections that are adjacent in space and the profile is relatively smooth and continuous. The three point cloud coordinates on the edge lines of the front and rear adjacent sections are connected in sequence to generate a triangle. Figure 3As shown, for the adjacent middle sections n and n+1, taking the points P(n,i), P(n+1,i) and P(n+1,i) as an example to construct a triangle, 2*(N-1)*M triangles are finally generated.

[0075] Create an obj format file named "inlet duct profile obj file"; store the total M*N three-dimensional point coordinates of the M sections of the inlet duct profile generated in step 2 into the obj format file line by line, and the format of each line is "v p1 p2 p3", p1, p2 and p3 are the three dimensional values ​​of the three-dimensional point coordinates respectively; store 2*(N-1)*M triangle information into the obj format file line by line, and the format of each line is "f v1 v2 v3", v1, v2 and v3 are the number of rows of the three points of the triangle in the obj format file respectively.

[0076] The process of high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function is as follows:

[0077] In the UI interface, an OpenGLControl control is established to display the three-dimensional effect of the air intake surface. The file with triangular mesh information generated in step 2 is used to read the M*N vertices and 2*(N-1)*M triangles in the file, and the corresponding relationship of a triangle is determined according to the three points to form a logical triangular face. The material parameters and light source parameters of the three-dimensional model of the air intake surface in OpenGLControl are set, and the normal vector information, area information and side length information of each triangular face are calculated in turn. All triangular faces are traversed, and for each triangular face, the method of constructing triangular primitives in OpenGL is used to draw triangular faces with normal information, and finally they are spliced ​​into a complete surface of the air intake with good material and lighting rendering effects.

[0078] Auxiliary observation functions include rotation, scaling, light source color change, inlet surface model material change, point cloud effect display, and grid effect display of the three-dimensional model of the air intake surface on the UI interface.

[0079] The method of the present invention integrates ultra-compact inlet duct surface generation and three-dimensional visualization. It can edit, control and visually display the inlet duct surface parameters through different design modes, display the key geometric feature information of the designed inlet duct, and realize simple dynamic display and high-quality dynamic display of the inlet duct surface three-dimensional model with auxiliary observation function.

[0080] In addition, based on the above-mentioned ultra-compact air intake duct profile auxiliary design method, the present invention also proposes a corresponding ultra-compact air intake duct profile auxiliary design system.

[0081] The ultra-compact air intake profile auxiliary design system includes:

[0082] The air intake profile design module is used to edit and control the various parameter values ​​of the air intake profile on the UI interface by importing a custom model file mode or a self-design mode. After the values ​​of various parameters are confirmed, the discrete information of the air intake profile structure is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and partial geometric feature parameter values ​​are displayed on the UI interface;

[0083] A simple 3D dynamic display module is used to realize the simple dynamic display of the 3D model of the inlet surface with auxiliary observation function based on the spatial characteristics of the discrete information of the inlet surface structure generated by the inlet surface design module, based on the method of drawing quadrilateral primitives in the open graphics library OpenGL, including the display of the inlet symmetry surface and the inlet grid effect, and the generation of the point cloud coordinate file of the model;

[0084] As well as a high-quality dynamic three-dimensional display module, it is used to generate triangular mesh information and save related three-dimensional format files based on the spatial characteristics of the point cloud information of the three-dimensional model of the air inlet surface generated by the simple three-dimensional dynamic display module, and realize high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function through OpenGL.

[0085] It should be noted that, in the above-mentioned ultra-compact air intake profile auxiliary design system, the implementation process of the functions and effects of each module is specifically described in the implementation process of the corresponding steps in the above-mentioned method, and will not be repeated here.

[0086] The present invention can parameterize the design of the air intake duct profile model and quickly provide feedback on the visual design results of the model, which is of great significance for assisting air intake duct designers in designing an ultra-compact air intake duct profile structure.

[0087] Of course, the above description is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It should be noted that all equivalent substitutions and obvious deformation forms made by any technician familiar with the field under the guidance of this specification fall within the essential scope of this specification and should be protected by the present invention.

Claims

1. An ultra-compact air inlet profile auxiliary design method, characterized in that: The steps include: Step 1. Edit and control the various parameter values ​​of the inlet profile on the UI interface by importing the custom model file mode or the self-design mode. After the values ​​of various parameters are confirmed, the discrete information of the three-dimensional model of the inlet profile is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and partial geometric feature parameter values ​​are displayed on the UI interface; In step 1, the generation of discrete information of the three-dimensional model of the air inlet profile and the display of various key geometric characteristic parameter curves and partial geometric characteristic parameter values ​​are as follows: After confirming the parameters of the inlet profile, the discrete data of the edge profiles of M intermediate transition sections of the inlet profile are generated based on the curvature-controlled cross-section shape transition generation method. The intermediate transition sections are evenly distributed along the direction perpendicular to the center line of the inlet, and the center line passes perpendicularly through the center point of each section; each intermediate transition section edge profile consists of N discrete points; a two-dimensional array of M rows and N columns in the C# programming language is used to temporarily store the coordinates of M*N discrete points of the M intermediate transition sections; where M and N are both natural numbers greater than 0; According to the temporarily stored discrete data of the air intake profile, i.e., M*N discrete point coordinates, 6 FormsPlot coordinate graphs for displaying the curves of various key geometric characteristic parameters are established on the UI interface; According to the temporarily stored discrete data of the inlet profile, some geometric features of the inlet profile are calculated, including: The maximum curvature of the upper wall, the maximum curvature of the centerline, the maximum curvature of the lower wall, the ratio of the maximum width to the total length, the ratio of the maximum height to the total length, and the ratio of the length to the diameter of the exit circle; Add corresponding TextBox controls on the UI interface to display the corresponding geometric feature parameter values; Step 2. Based on the spatial characteristics of the discrete information of the three-dimensional model of the air intake surface generated in step 1, a simple dynamic display of the three-dimensional model of the air intake surface with an auxiliary observation function is realized based on the method of drawing quadrilateral primitives in the open graphics library OpenGL, including the display of the air intake symmetry surface and the air intake grid effect and the generation of a point cloud coordinate file of the model; Step 3. Based on the spatial features of the point cloud information of the three-dimensional model of the air inlet surface generated in step 2, generate triangular mesh information according to the triangular meshing method and save the relevant three-dimensional format file, and use OpenGL to achieve high-quality dynamic display of the three-dimensional model of the air inlet surface with auxiliary observation function.

2. The ultra-compact air intake duct profile auxiliary design method according to claim 1, characterized in that: In step 1, in the custom model file import mode, the process of displaying and editing the parameters of the air intake duct profile on the UI interface is as follows: Read the parameter values ​​of the air inlet profile in the custom model file line by line; For non-section and change law parameter values, use the Text property of the data display box TextBox to receive them. When the parameter value needs to be modified, edit the value in the data display box and trigger the TextChange() function to update the parameter value in the background. For cross sections and change rules, parse the corresponding single-line mixed description information in the custom model file, display all cross section entities and change rule entities in the UI interface, and set them according to the parameter values ​​in the file and their position index in the file; Based on the ScottPlot interactive drawing library under the Windows Form platform, two FormsPlot coordinate graph control drawing positions are established in the UI interface to facilitate the display of cross-sectional shapes and change law curves; When the system imports a custom model file and reads it or creates it by itself, the setup function is called; The function is set as follows: load the FormsPlot coordinate graph display interface and the drawing curve drawing animation, set the coordinate graph title and the color of the curve, and bind the coordinate values ​​of the cross section or change law to the preset X-axis and Y-axis respectively; According to the currently selected section or change rule, use AddScatterLines() to set the corresponding edge line coordinates or curve coordinates as the curve coordinates in the FormPlot coordinate diagram; When different sections and change rules are selected, use Clear() to clear the curve data in the FormPlot control, and use AddScatterLines() to add the coordinate information of the currently selected section or change rule to redraw the curve.

3. The ultra-compact air intake duct profile auxiliary design method according to claim 1, characterized in that: In step 1, in the self-design mode, the process of displaying and editing the parameters of the air intake profile on the UI interface is as follows: For non-section and variation law parameter values, the Text property of the data display box TextBook is used to receive the parameter values ​​edited and input by the user, and is updated synchronously when the inlet profile is generated next time; for the required section, the classic section shape provided by the system is selected, and the corresponding shape parameter values ​​are modified to create a specific section entity; for the required variation law, the classic variation law provided by the system is selected, and the corresponding curve parameter values ​​are modified to create a specific variation law entity; According to the created section entity, the key sections are set respectively; according to the created change rule entity, the lateral change rule of the center line of the air inlet and the area change rule are set respectively; In the self-design mode, use the FormsPlot control in the ScottPlot interactive drawing library to display the created cross-sectional shape and change law curve.

4. The ultra-compact air intake duct profile auxiliary design method according to claim 1, characterized in that: In step 2, the process of simple dynamic display of the three-dimensional model of the air intake profile with auxiliary observation function is as follows: Create an OpenGLControl control in the UI interface to display the 3D model drawn by OpenGL; Using the discrete information of the three-dimensional model of the air intake duct surface temporarily stored in the two-dimensional array of M rows and N columns in step 1, using the method of constructing quadrilateral primitives in OpenGL, draw M*(N-1) adjacent quadrilaterals, and fill each quadrilateral with a custom color, so as to realize the complete air intake duct surface display effect in the OpenGLControl control; For auxiliary observation function, the system provides Button controls for displaying the left section of the inlet profile, Button controls for displaying the right section of the inlet profile, and Button controls for displaying the mesh effect of the inlet profile. By clicking the corresponding button to trigger the click() function, the OpenGL drawing function is adjusted to achieve the corresponding display effect; For the dynamic transition effect display of the air intake surface, use the NumericUpDown digital increase and decrease control to bind the total number of sections K involved in constructing the quadrilateral primitive, that is, use the first K sections to construct the quadrilateral primitive, K≤M; When the K value in the NumericUpDown control is modified, the intake duct profile in the OpenGLControl control will only transition and display to the Kth section. Use the NumericUpDown control to control the K value to increase from 0 to M, which fully displays the dynamic transition effect of the overall intake duct profile.

5. The ultra-compact air intake duct profile auxiliary design method according to claim 1, characterized in that: In step 2, the process of generating the point cloud coordinate file of the air inlet surface model is as follows: Using the discrete information of the three-dimensional model of the air inlet surface temporarily stored in the two-dimensional array of M rows and N columns in step 1, create a txt format file, and traverse the two-dimensional array of M rows and N columns; Each time a coordinate element is traversed, the x-axis coordinate value, y-axis coordinate value, and z-axis coordinate value of the coordinate are added to the next line in the txt format file, separated by spaces, until the traversal is completed. There are a total of M*N lines of coordinate information in the txt format file.

6. The ultra-compact air inlet profile auxiliary design method according to claim 4, characterized in that: In step 3, the process of using the triangular meshing method to generate the triangular mesh information of the profile is as follows: For the point cloud information of the three-dimensional model of the air inlet profile generated in step 2, the air inlet profile is composed of M intermediate sections that are adjacent in space and the profile is relatively smooth and continuous. The three point cloud coordinates on the edge lines of the front and rear adjacent sections are connected in sequence to generate triangles, and finally 2*(N-1)*M triangles are generated; Create an obj format file; store the total M*N three-dimensional point coordinates of the M sections of the inlet duct profile generated in step 2 into the obj format file line by line, and the format of each line is "v p1 p2 p3", and p1, p2 and p3 are the three dimensional values ​​of the three-dimensional point coordinates respectively; store 2*(N-1)*M triangle information into the obj format file line by line, and the format of each line is "f v1 v2 v3", and v1, v2 and v3 are the number of rows of the three points of the triangle in the obj format file respectively.

7. The ultra-compact air inlet profile auxiliary design method according to claim 6, characterized in that: In step 3, the process of high-quality dynamic display of the three-dimensional model of the air inlet profile with auxiliary observation function is as follows: Create an OpenGLControl control in the UI interface to display the three-dimensional effect of the air intake surface; Using the file with triangular mesh information generated in step 2, read the M*N vertices and 2*(N-1)*M triangles in the file, and determine the corresponding relationship of 1 triangle according to the 3 points to form a logical triangular face; Set the material parameters and light source parameters of the intake duct surface 3D model in OpenGLControl, and calculate the normal vector information, area information and side length information of each triangle face in turn; Traverse all triangular facets, and for each triangular facet, use the method of constructing triangular primitives in OpenGL to draw a triangular facet with normal information, and finally splice it into a complete surface of the air intake; Auxiliary observation functions include rotation, scaling, light source color change, inlet surface model material change, point cloud effect display, and grid effect display of the three-dimensional model of the air intake surface on the UI interface.

8. An ultra-compact air intake duct profile auxiliary design system for implementing the ultra-compact air intake duct profile auxiliary design method according to claim 1, characterized in that: The ultra-compact air inlet profile auxiliary design system comprises: The air intake duct profile design module is used to edit and control the various parameter values ​​of the air intake duct profile on the UI interface by importing a custom model file mode or a self-design mode. After the values ​​of various parameters are confirmed, the discrete information of the three-dimensional model of the air intake duct profile is generated based on the curvature-controlled cross-sectional shape transition generation method, and the key geometric feature parameter curves and partial geometric feature parameter values ​​are displayed on the UI interface; A simple 3D dynamic display module is used to realize the simple dynamic display of the 3D model of the air intake profile generated by the air intake profile design module based on the spatial characteristics of the discrete information of the 3D model of the air intake profile. The module can be used to display the symmetry surface of the air intake and the mesh effect of the air intake, and to generate the point cloud coordinate file of the model. And a high-quality dynamic three-dimensional display module is used to generate triangular mesh information and save related three-dimensional format files based on the spatial characteristics of the point cloud information of the three-dimensional model of the air intake surface generated by the simple three-dimensional dynamic display module, and realize high-quality dynamic display of the three-dimensional model of the air intake surface with auxiliary observation function through OpenGL.

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