A method and computer equipment for constructing a leaf root leading edge structure model

Abstract

This invention relates to the field of integral bladed disk design technology, specifically to a method and computer device for constructing a blade root leading edge structure model. The method for constructing the blade root leading edge structure model provided by this invention includes: obtaining multiple first blade profiles of equal height based on a preset three-dimensional blade root model; determining the mid-curve of each first blade profile in each first blade profile; determining the position of the leading edge circle on the extension line of each mid-curve based on preset parameters, and generating a spline curve based on the leading edge circle; generating multiple second blade profile leading edges by fitting the multiple leading edge circles and the leading edges of the multiple first blade profiles; and generating a blade root leading edge structure model based on the spline curve and the multiple second blade profile leading edges. By implementing this invention, the curvature of the surface of the blade root leading edge structure model can be reduced by adjusting the shape of the spline curve and the leading edges of the second blade profiles, thus avoiding high stress points.

Description

Technical Field

[0001] This invention relates to the field of integral bladed disk design technology, specifically to a method for constructing a blade root leading edge structure model and a computer device. Background Technology

[0002] Integral bladed disks (IBDs) are a new type of structural component designed to meet the requirements of high-performance aero engines. They integrate the engine rotor blades and the disk into one unit. When constructing rotor blade models, fully parametric blade design is usually adopted. Key parameters (inlet and outlet angles, installation angles, chord lengths, etc.) and spline airfoil profiles are used to control the cross-sectional airfoil. Then, the stacking rules are given to achieve the three-dimensional shape of the blade. The transition connection between the blade root and the disk is usually achieved by direct chamfering. However, because the surface curvature of the blade root leading edge structure obtained by this connection method is large, high stress points are prone to appear, which can lead to fatigue fracture of the blade. Summary of the Invention

[0003] Therefore, the present invention provides a method and computer device for constructing a blade root leading edge structure model, so as to overcome the defect that high stress points are easily generated when the blade root of the integral bladed disk in the prior art is only chamfered to achieve the transition connection between the blade and the disk.

[0004] To address the aforementioned problems, this invention provides a method for constructing a blade root leading edge structure model, comprising: obtaining multiple first blade profiles with equal cross-sectional heights based on a preset three-dimensional blade root model; determining the blade profile mid-curve of each of the first blade profiles in each first blade profile; determining the position of the leading edge circle on the extension line of each blade profile mid-curve based on preset parameters, and generating a spline curve based on the leading edge circle; generating multiple second blade profile leading edges by fitting the multiple leading edge circles and the leading edges of the multiple first blade profiles; and generating a blade root leading edge structure model based on the spline curve and the multiple second blade profile leading edges.

[0005] Optionally, the process of determining the extension line of the mid-arc line of each of the first blade sections includes: approximating the mid-arc line of the blade at the leading edge of the blade root as a circular arc, and extending the circular arc towards the leading edge of the blade root by a predetermined length to form multiple extension arcs.

[0006] Optionally, determining the position of the leading edge circle on the extension line of the arc in each of the blade profiles based on preset parameters, and generating a spline curve based on the leading edge circle, includes: drawing the leading edge circle with the end of the extension arc away from the first blade profile cross-section as the center, the radius of the leading edge circle being the same as the radius corresponding to the arc on the first blade profile cross-section close to the leading edge circle; and sequentially connecting the centers of multiple leading edge circles to generate the spline curve.

[0007] Optionally, after generating the spline curve by sequentially connecting the centers of multiple leading edge circles, the step of determining the position of the leading edge circle on the extension line of the arc in each leaf shape based on preset parameters, and generating the spline curve based on the leading edge circle, further includes: adjusting the arc length of the extension arc according to the included angle between each segment of the spline curve.

[0008] Optionally, the radii of each of the leading edge circles gradually decrease in the order of arrangement away from the leaf root.

[0009] Optionally, the arc length of each of the extended arcs gradually decreases in the order of arrangement away from the leaf root.

[0010] Optionally, in the leading edge of the second blade section, the two ends of the arc connecting the leading edge circle and the first blade section are tangent to the leading edge circle and the leading edge of the first blade section, respectively, and the leading edge of the second blade section matches the shape of the leading edge of the first blade section.

[0011] Optionally, determining the airfoil mid-arc line of each of the first airfoil sections includes: generating multiple airfoil inscribed circles in each of the first airfoil sections, and sequentially connecting the centers of the multiple airfoil inscribed circles to form the airfoil mid-arc line.

[0012] Optionally, the height difference between adjacent first airfoil sections is equal.

[0013] The present invention also provides a computer device, including: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the method for constructing the leaf root leading edge structure model described in any of the above embodiments.

[0014] The present invention has the following advantages:

[0015] 1. The method for constructing a blade root leading edge structure model provided by the present invention includes obtaining multiple first blade profiles with equal cross-sectional heights based on a preset three-dimensional blade root model; determining the blade profile mid-curve of each first blade profile in each first blade profile; determining the position of the leading edge circle on the extension line of each blade profile mid-curve based on preset parameters, and generating a spline curve based on the leading edge circle; generating multiple second blade profile leading edges based on the multiple leading edge circles and the leading edges of the multiple first blade profiles; and generating a blade root leading edge structure model based on the spline curve and the multiple second blade profile leading edges.

[0016] In this method, the leading edge circle is first determined according to preset parameters. A spline curve and a second blade profile leading edge are then generated based on this circle. Finally, a blade root leading edge structure model is generated using the spline curve and the second blade profile leading edge. The curvature of the blade root leading edge structure model surface is determined by the shape of the spline curve and the second blade profile leading edge. By adjusting the shape of the spline curve and the second blade profile leading edge, the curvature of the blade root leading edge structure model surface can be reduced, thereby avoiding high-stress points on the surface of the model and preventing fatigue fracture of blades manufactured based on this model during use. Compared to the method of directly chamfering at the blade root, the construction method provided in this embodiment allows for more parameters to adjust the curvature of the blade root leading edge structure model surface, making it easier to obtain a blade root leading edge structure that meets stress requirements.

[0017] 2. The method for constructing the leading edge structure model of the leaf root provided by the present invention, after generating spline curves by sequentially connecting the centers of multiple leading edge circles, determines the position of the leading edge circle on the extension line of the arc in each leaf shape based on preset parameters, and generates spline curves based on the leading edge circle, further includes: adjusting the arc length of the extension arc according to the included angle between each segment of the spline curve.

[0018] In essence, by adjusting the arc length of two adjacent extension arcs, the angle between the tangents of adjacent segments in the spline curve is changed, resulting in a smoother spline curve. This prevents large curvature variations in the spline curve due to inaccuracies in the arc length of the extension arcs, thereby reducing the curvature of the blade root leading edge structure model surface and avoiding high-stress points on the surface. Furthermore, adjusting the arc length of the extension arcs is simple, quick, and has a low difficulty level. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 A flowchart illustrating the construction method of the leaf root leading edge structure model provided by the present invention is shown.

[0021] Figure 2 This invention illustrates a first airfoil section with multiple equal cross-sectional heights in the method for constructing the airfoil root leading edge structure model provided by the present invention.

[0022] Figure 3 The diagram shows the mid-arc lines of each first airfoil section in the method for constructing the airfoil root leading edge structure model provided by the present invention.

[0023] Figure 4 The diagram illustrates the extension arc of the mid-arc line in each first airfoil section of the method for constructing the airfoil root leading edge structure model provided by the present invention.

[0024] Figure 5 The diagram illustrates the leading edge circle in the method for constructing the leaf root leading edge structure model provided by this invention.

[0025] Figure 6 The spline curves in the method for constructing the leaf root leading edge structure model provided by the present invention are shown.

[0026] Figure 7 The first blade-shaped section leading edge is shown in the method for constructing the blade root leading edge structure model provided by the present invention.

[0027] Figure 8 The leaf root leading edge structure model is shown in the method for constructing the leaf root leading edge structure model provided by the present invention.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. First airfoil section; 2. Airfoil mid-curve; 3. Leading edge circle; 4. Spline curve; 5. Leading edge of the second airfoil section. Detailed Implementation

[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] This embodiment provides a method for constructing a leaf root leading edge structure model, such as... Figure 1 As shown, the method mainly includes:

[0035] Step S101: Obtain multiple first blade section sections 1 with equal cross-sectional heights based on the preset blade root 3D model; wherein, the preset blade root 3D model refers to the structural model at the blade root of the blade on the overall bladed disk generated in 3D modeling software according to design requirements. It should be noted that the preset blade root 3D model does not meet the stress level requirements; such as Figure 2 As shown, the plurality of first airfoil sections 1 with equal cross-sectional heights are the contour curves of each cross-section obtained by intersecting the airfoil root with a plurality of mutually parallel ideal planes. Optionally, the height difference between adjacent first airfoil sections 1 is equal; for example, the height difference between adjacent first airfoil sections 1 can be 1 mm.

[0036] Step S102: As Figure 3 As shown, the airfoil mid-arc line 2 is determined in each of the first airfoil sections 1; that is, multiple airfoil inscribed circles are generated in each of the first airfoil sections 1, and the centers of the multiple airfoil inscribed circles and the lines extending tangentially from the centers of the leading and trailing edges to intersect the same leading and trailing edges are connected in sequence to form the airfoil mid-arc line 2. Furthermore, the distance between the centers of any two adjacent airfoil inscribed circles is the same. The number of generated airfoil inscribed circles is not further limited here; for example, it can be 20. The more airfoil inscribed circles there are, the smaller the error of the airfoil mid-arc line 2 obtained from the first airfoil section 1.

[0037] Step S103: Based on preset parameters, determine the position of the leading edge circle 3 on the extension line of the arc 2 in each of the blade profiles, and generate a spline curve 4 based on the leading edge circle 3. The preset parameters are manually set values ​​and are not further limited here. Optionally, as follows... Figure 4As shown, in step S103, the process of determining the extension line of the mid-arc line 2 of each of the first blade section 1 includes approximating the mid-arc line 2 at the leading edge of the blade root as an arc, and extending the arc towards the leading edge of the blade root by a preset length to form multiple extended arcs. It should be noted that the preset length is a manually set parameter and is not further limited here. The arc length parameter of the extended arc is... Figure 5 The value of parameter L. Optionally, the arc lengths of each of the extended arcs gradually decrease in the order away from the leaf root. By approximating the arc 2 of the blade shape at the leading edge of the leaf root as a circular arc, the extension direction of the extended arcs is made more accurate. This avoids the situation where the extension directions of the various segments of the arc 2 of the blade shape are inconsistent. If an extended arc is obtained by arbitrarily lengthening one of the segments, the extension directions of the extended arcs obtained from different segments will be different, which will lead to errors in the shape of the spline curve 4.

[0038] Step S104: Generate multiple second airfoil section leading edges 5 based on the leading edge fitting of the multiple leading edge circles 3 and the multiple first airfoil sections 1. Optionally, as... Figure 7 As shown, in the leading edge 5 of the second blade section, the two ends of the arc connecting the leading edge circle 3 and the first blade section 1 are tangent to the leading edge circle 3 and the leading edge of the first blade section 1, respectively. The leading edge 5 of the second blade section matches the leading edge shape of the first blade section 1. That is, when the leading edge of the first blade section 1 is a convex blade, the leading edge 5 of the second blade section is also a convex blade. When the leading edge of the first blade section 1 is a concave blade, the leading edge 5 of the second blade section is also a concave blade. This avoids changing the twisting direction of the blade and prevents blade profile distortion.

[0039] Step S105: As Figure 8 As shown, a blade root leading edge structure model is generated based on the spline curve 4 and multiple second airfoil section leading edges 5. Specifically, the "Through Curve Group" command in UG NX7.5 is used to connect the multiple second airfoil section leading edges 5 to obtain the blade root leading edge structure model. The blade root leading edge structure is a section of the blade root leading edge that extends naturally along the blade direction on the inner flow channel surface and is smoothly connected to the blade leading edge, the inner flow channel surface, and the blade root chamfer.

[0040] Step S106: Perform stress level verification on the blade root leading edge structure model. If the blade root leading edge structure model does not meet the stress level requirements, adjust the smoothness of the spline curve 4 accordingly, that is, adjust the arc length of the extended arc, regenerate the blade root leading edge structure model, and then perform stress level verification again until the blade root leading edge structure model meets the stress level requirements. The method of stress level verification is not further described here.

[0041] In this method, the leading edge circle 3 is first determined according to the preset parameters. Then, the spline curve 4 and the second airfoil section leading edge 5 are generated based on the leading edge circle 3. Finally, a blade root leading edge structure model is generated using the spline curve 4 and the second airfoil section leading edge 5. The curvature of the blade root leading edge structure model surface is determined by the shapes of the spline curve 4 and the second airfoil section leading edge 5. By adjusting the shapes of the spline curve 4 and the second airfoil section leading edge 5, the curvature of the blade root leading edge structure model surface can be reduced, thereby avoiding high stress points on the surface of the blade root leading edge structure model and preventing fatigue fracture of blades manufactured based on this model during use. Compared to the method of directly chamfering at the blade root, the construction method provided in this embodiment allows for more parameters to adjust the curvature of the blade root leading edge structure model surface, making it easier to obtain a blade root leading edge structure that meets stress requirements.

[0042] Optionally, such as Figures 5 to 6 As shown, step S103 determines the position of the leading edge circle 3 on the extension line of the arc line 2 in each of the blade shapes based on preset parameters, and generates a spline curve 4 based on the leading edge circle 3, including:

[0043] Step S1031: Draw the leading edge circle 3 with the end of the extended arc away from the first airfoil section 1 as the center. The radius of the leading edge circle 3 is the same as the radius corresponding to the arc on the first airfoil section 1 near the leading edge circle 3; wherein, the radius parameter of the leading edge circle 3 is... Figure 5 The value of parameter r is shown. Optionally, the radii of each of the leading edge circles 3 are arranged in a sequence away from the leaf root, gradually decreasing, thereby satisfying the requirement that the thickness of the leaf gradually decreases from the leaf root to the leaf tip.

[0044] Step S1032: Connect the centers of multiple leading edge circles 3 in sequence to generate the spline curve 4.

[0045] Step S1033: Adjust the arc length of the extended arc according to the angle between each segment of the spline curve 4. This achieves the smoothing operation of the spline curve 4. As an alternative implementation, the smoothing operation of the spline curve 4 in step S1033 can be performed using linear least squares fitting. Since this method is existing technology, it will not be described further here.

[0046] Specifically, by adjusting the arc length of two adjacent extension arcs, the angle between the tangents of adjacent curve segments in the spline curve 4 is changed, resulting in a smaller angle between the tangents of each adjacent curve segment. This produces a smoother and more even spline curve 4, preventing large curvature variations in the spline curve 4 due to inaccuracies in the arc length of the extension arcs. This reduces the curvature of the surface of the blade root leading edge structure model, avoiding high-stress points on its surface. Furthermore, adjusting the arc length of the extension arcs is simple, quick, and has a low difficulty level.

[0047] This invention also provides a computer device, including a memory and a processor, wherein the memory and the processor are communicatively connected to each other, and wherein the processor and the memory can be connected via a bus or other means. The memory stores computer instructions, and the processor executes the computer instructions to perform the aforementioned method for constructing the leaf root leading edge structure model.

[0048] Optionally, the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations thereof.

[0049] Optionally, the memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions or modules corresponding to the method for constructing the leaf root leading edge structure model in the embodiments of the present invention. The processor executes various functional applications and data processing by running the non-transitory software programs, instructions, and modules stored in the memory, thereby implementing the method for constructing the leaf root leading edge structure model in the above method embodiments.

[0050] Optionally, the memory may include a program storage area and a data storage area, wherein the program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the processor, etc. Furthermore, the memory may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0051] The one or more modules are stored in the memory, and when executed by the processor, they perform actions such as... Figure 1 The method for constructing the leaf root leading edge structure model in the illustrated embodiment.

[0052] For specific details regarding the aforementioned computer equipment, please refer to the relevant documentation. Figures 1 to 8 The relevant descriptions and effects in the illustrated embodiments are for understanding purposes only and will not be repeated here.

[0053] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0054] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for constructing a leaf root leading edge structure model, characterized in that, include: Based on the preset three-dimensional model of the blade root, obtain multiple first blade sections with equal cross-sectional height (1); In each of the first airfoil sections (1), the airfoil mid-arc line (2) is determined respectively; Based on preset parameters, the position of the leading edge circle (3) is determined on the extension line of the arc (2) in each of the blade shapes, and a spline curve (4) is generated based on the leading edge circle (3); Multiple second airfoil section leading edges (5) are generated based on the leading edge fitting of multiple leading edge circles (3) and multiple first airfoil sections (1); The leaf root leading edge structure model is generated based on the spline curve (4) and the leading edges (5) of multiple second leaf-shaped sections.

2. The method for constructing the leaf root leading edge structure model according to claim 1, characterized in that, The process of determining the extension line of the mid-arc line (2) of each of the first airfoil sections (1) includes: The arc (2) in the leaf shape at the leading edge of the leaf root is approximated as a circular arc, and the circular arc is extended to the leading edge of the leaf root by a predetermined length to form multiple extended arcs.

3. The method for constructing the leaf root leading edge structure model according to claim 2, characterized in that, The step of determining the position of the leading edge circle (3) on the extension line of the arc line (2) in each of the blade shapes based on preset parameters, and generating a spline curve (4) based on the leading edge circle (3), includes: With the end of the extended arc away from the first blade section (1) as the center, draw the leading edge circle (3), and the radius of the leading edge circle (3) is the same as the radius of the arc on the first blade section (1) close to the leading edge circle (3); The spline curve (4) is generated by sequentially connecting the centers of multiple leading edge circles (3).

4. The method for constructing the leaf root leading edge structure model according to claim 3, characterized in that, After generating the spline curve (4) by sequentially connecting the centers of multiple leading edge circles (3), the step of determining the position of the leading edge circle (3) on the extension line of the arc line (2) in each blade shape based on preset parameters, and generating the spline curve (4) based on the leading edge circle (3), further includes: The arc length of the extended arc is adjusted according to the angle between each segment of the spline curve (4).

5. The method for constructing the leaf root leading edge structure model according to claim 3 or 4, characterized in that, The radii of each of the leading edge circles (3) decrease gradually in the order of their arrangement away from the leaf root.

6. The method for constructing the leaf root leading edge structure model according to any one of claims 2-4, characterized in that, The arc lengths of each of the extended arcs gradually decrease in the order of their arrangement away from the leaf root.

7. The method for constructing the leaf root leading edge structure model according to any one of claims 1-4, characterized in that, In the leading edge (5) of the second blade section, the two ends of the arc connecting the leading edge circle (3) and the first blade section (1) are tangent to the leading edge circle (3) and the leading edge of the first blade section (1), respectively, and the leading edge (5) of the second blade section matches the leading edge shape of the first blade section (1).

8. The method for constructing the leaf root leading edge structure model according to any one of claims 1-4, characterized in that, The step of determining the airfoil mid-curve (2) of each of the first airfoil sections (1) includes: Multiple inscribed circles are generated in each of the first blade section (1), and the centers of the multiple inscribed circles are connected in sequence to form the mid-arc line (2) of the blade.

9. The method for constructing the leaf root leading edge structure model according to any one of claims 1-4, characterized in that, The height difference between adjacent first blade sections (1) is equal.

10. A computer device, characterized in that, include: A memory and a processor are interconnected, the memory stores computer instructions, and the processor executes the computer instructions to perform the method for constructing the leaf root leading edge structure model according to any one of claims 1-9.

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