Hydraulic torque converter blade parameterization design method fusing catenary and cycloid

Abstract

The invention belongs to the technical field of hydraulic transmission of engineering machinery, and particularly relates to a catenary and cycloid fused hydraulic torque converter blade parameterization design method which innovatively applies a catenary and a cycloid to blade design. A catenary is used for constructing a bone line of the blade, a cycloid is used for designing a thickness distribution curve of the blade, and the shape of the blade is comprehensively parameterized, so that accurate design of the blade is facilitated; in addition, the method overcomes the limitation of traditional blade design in the aspects of curvature continuity and flexibility, the performance adjustable range of the hydraulic torque converter is remarkably widened, and the transmission efficiency and the power density of the hydraulic torque converter are improved; through the accurately designed blade shape, the flow loss in an impeller runner is reduced, the service life of the blade is prolonged, and powerful support is provided for high-performance development of the hydraulic torque converter.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic transmission of engineering machinery, and in particular to a parameterized design method for hydraulic torque converter blades integrating a catenary and a cycloid. Background Art

[0002] As an important component in the transmission system of engineering machinery, the torque converter is widely used in urban buses, engineering machinery, military tanks and other fields because of its advantages of torque multiplication, vibration isolation and stepless speed change. Modern engineering machinery is developing in the direction of high speed and high power. In order to meet the performance matching requirements of engineering machinery, the torque converter needs to be designed for high performance. The performance of the torque converter mainly depends on the impeller torque, and the impeller torque is obtained by integrating the product of the pressure on the blade surface and the rotation radius on the blade surface. Therefore, the design of a high-performance torque converter ultimately comes down to the blade design.

[0003] The design of hydraulic torque converter mainly includes circulation circle design and blade design, among which blade design is the core and most complex link in the design of hydraulic torque converter, and the quality of its design is directly related to the transmission power and efficiency of the hydraulic torque converter. The traditional design of hydraulic torque converter blades is mainly based on the circulation distribution method and conformal transformation design method of one-dimensional beam theory. In the design process of the circulation design method, the blade is assumed to be infinitely thin, and the intermediate streamline is used to replace the three-dimensional flow of the hydraulic torque converter, which will cause a large design error. The subsequent repeated corrections of experiments can meet the design requirements, which greatly prolongs the design cycle of the hydraulic torque converter. The traditional conformal transformation method is a blade skeleton design method based on straight line-parabola-straight line. The design is very arbitrary. At the same time, the use of straight lines results in the blade curve designed to have only the first-order derivative at most, which cannot meet the design requirements of streamline curves. Neither the circulation distribution method nor the conformal transformation design method can design hydraulic torque converter blades with large angles and large curvatures, resulting in a narrow adjustable performance range of the hydraulic torque converter, which cannot meet the needs of modern engineering machinery for high-speed and high-power transmission.

[0004] Aiming at the defects of traditional torque converter blade design theory during blade design, such as long blade design cycle, discontinuous blade design curvature, complicated blade design and narrow adjustable range of torque converter performance, it is urgent to propose a new torque converter blade design method, which aims to broaden the transmission performance of the torque converter, simplify the blade design process and improve the continuity of the blade curve. Summary of the invention

[0005] Technical issues solved

[0006] In order to overcome the above technical defects of the traditional torque converter blade design method, the present invention proposes a parametric design method for torque converter blades that integrates the catenary and the cycloid. This method completely parametrically expresses the curves of the entire impeller and the entire blade by applying the catenary and the cycloid to the blade structure design.

[0007] Technical Solution

[0008] To achieve the above purpose, the present invention proposes a parameterized design method for hydraulic torque converter blades that integrates catenary and cycloid, which respectively adopts catenary and cycloid to perform parameterized design of blade skeleton and blade thickness distribution curve. For the unit blade skeleton, the relationship between the unit blade skeleton parameters (blade inlet angle β1, blade outlet angle β2, blade inlet and blade outlet segment curve splicing point position (the present invention adopts parameter p (p>0) for control)) and catenary is established; for the unit blade thickness distribution curve, the blade thickness distribution curve parameters (thickness peak position x hmax and thickness peak height h max By changing the blade control parameters, the direction of the catenary and the cycloid can be controlled, and the blade curve can be precisely adjusted.

[0009] Furthermore, the present invention proposes a parameterized design method for a hydraulic torque converter blade that combines a catenary and a cycloid, comprising the following steps:

[0010] Step 1: Given the design parameters of the torque converter circulation circular curve, the torque converter circulation circular curve is obtained by the three-arc method. The torque converter circulation circular curve includes outer ring, inner ring streamlines and inlet and outlet edge straight lines;

[0011] The step 1 specifically includes:

[0012] The circulation circle is designed by the three-arc design method. For the specific method, please refer to the literature [Wang Yan, Wang Yupeng, Ma Wenxing; Comprehensive description and derivative correction method of the circulation circle of the torque converter, Journal of Jilin University (Engineering Edition), 32(1):79-82, 2002]. Among the three arcs, the centers of the first and third arcs are on the symmetry center line, and the second arc can be obtained from the first and third arcs according to the tangency. From the known effective diameter D and minimum diameter d0 of the torque converter, the radii r1 and r3 of the first and third arcs of the outer ring of the circulation circle and the width B of the circulation circle can be obtained, and the circulation circle can be designed as follows:

[0013]

[0014] Step 2: Given the design parameters of the torque converter unit blade skeleton, first give the blade inlet and outlet angles β1 and β2, and then construct the unit skeleton through two catenary segments;

[0015] The step 2 specifically includes:

[0016] The unit blade skeleton is constructed by splicing two catenary segments. The equation of the catenary can be expressed as:

[0017]

[0018] Where a is the shape factor of the catenary. The first catenary can determine the value of the shape factor a1 according to the blade inlet angle β1, and the second catenary can determine the value of the shape factor a2 according to the blade outlet angle β2, and then the position of the parameter p (p>0) is used to control the blade bone line peak. The two catenary segments are spliced ​​at the origin to form a reference bone line, and then the unit blade bone line can be obtained by moving.

[0019] Based on the catenary principle, the two-segment catenary equations of the blade skeleton can be preliminarily obtained. For the first catenary, the present invention selects its curve in the second quadrant and controls its horizontal coordinate with the parameter p-1, that is, the range of the horizontal coordinate is [p-1, 0]. For the second catenary, we select its curve in the first quadrant and control its horizontal coordinate with the parameter p, that is, the range of the horizontal coordinate is [0, p]. Then, according to the relationship between the inlet and outlet angles β1 and β2 of the torque converter blade and the tangent slopes at the starting and ending points of the two catenaries, as well as the relationship between the ending point of the first catenary and the starting point of the second catenary, the shape factor a of the two catenaries can be obtained.

[0020] The equation of the first catenary segment is as follows:

[0021]

[0022] The equation of the second catenary segment is as follows:

[0023]

[0024] The relationship between the tangent line at the starting point of the first catenary segment and the blade inlet angle is as follows:

[0025]

[0026] The end points of the first catenary segment and the starting points of the second catenary segment are:

[0027]

[0028] The relationship between the tangent line at the dead point of the second catenary segment and the blade outlet angle is as follows:

[0029]

[0030] Splice the first and second catenary segments, and then move them to get the unit blade skeleton equation:

[0031]

[0032] Step 3: Given the torque converter unit blade thickness distribution parameters, the unit blade thickness distribution is constructed through two cycloids;

[0033] The step 3 specifically includes:

[0034] The thickness distribution of the unit blade is constructed using two cycloids. The cycloid equation is:

[0035]

[0036] Among them, ρ is the radius of the rolling circle, which determines the size of the cycloid. The larger the ρ value, the smoother the leading and trailing edges of the constructed blades. t is the rolling angle. Sint and cost are sine and cosine functions, respectively, which describe the position change of the fixed point on the circle relative to the center of the circle in the cycloid equation. The first segment of the cycloid is selected in the present invention as [0, π], and the second segment of the cycloid is selected as [π, 2π]. The ordinates are adjusted by scaling so that the ordinate values ​​of the two segments of the cycloid at t = π are h max Then, the horizontal coordinate is adjusted by scaling and translating so that the horizontal coordinate of the spliced ​​curve has a value range of [0, 1], and the unit leaf thickness distribution curve can be obtained.

[0037] The equation of the first cycloid is as follows:

[0038]

[0039] Among them, k x1 , k h1 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf.

[0040] The equation of the second cycloid is as follows:

[0041]

[0042] Among them, k x2 , k h2 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf.

[0043] The tangent line at the starting point of the first cycloid has the following relationship:

[0044]

[0045] The relationship between the end point of the first cycloid and the starting point of the second cycloid is as follows:

[0046]

[0047] The tangent line at the dead point of the second cycloid has the following relationship:

[0048]

[0049] Step 4: The suction surface and pressure surface curves of the unit blade can be obtained by superimposing the thickness of the obtained unit blade bone line. The slope of each point on the bone line can be obtained by taking the derivative of the bone line. The normal direction of each point on the bone line can be obtained by using the perpendicular relationship between the tangent line and the normal line. The suction surface and pressure surface coordinates of the unit blade can be obtained by superimposing the thickness on the normal line.

[0050] The step 4 specifically includes:

[0051] First, the tangent slope θ of each point on the bone line can be obtained by taking the derivative of the bone line. According to the geometric relationship, the angle θ between the normal line at each point on the bone line and the positive direction of the x-axis can be obtained. Finally, the thickness is superimposed on the normal line to obtain the coordinates of the suction surface and pressure surface of the unit blade. The equations for derivative and thickness superposition are:

[0052]

[0053] Where θ is the angle between the tangent line of each point of the bone line and the x-axis; y c is the ordinate of the unit leaf bone line, h is the ordinate of the unit leaf thickness distribution curve, (x u ,y u ) is the pressure surface coordinate of the unit blade; (x d ,y d ) is the suction surface coordinate of the unit blade.

[0054] Step 5: Scale, mirror and rotate the suction surface and pressure surface curves of the unit blade to obtain a real two-dimensional blade, and then obtain a real three-dimensional blade through generalized conformal transformation mapping. Finally, construct straight lines and sew to generate a three-dimensional blade.

[0055] The step 5 specifically includes:

[0056] The pressure surface and suction surface curves of the unit blade are scaled, rotated and mirrored to obtain the real two-dimensional blade shape curve. The specific formula is:

[0057]

[0058] Among them, (S u , L u ) is the real two-dimensional blade pressure surface coordinate, (S d , L d ) is the coordinate of the real two-dimensional blade suction surface, L is the length of the inner and outer ring curves intercepted by the inlet and outlet edges of the blade on the circulation circle, is the rotation angle.

[0059] After generalized conformal transformation mapping, the corresponding relationship between the coordinates of the inner and outer rings of the two-dimensional blade and the three-dimensional coordinates is:

[0060]

[0061] Among them, R i Represents the R coordinate (i.e., ordinate) of the corresponding point in the circular view, θ i It represents the angle between the line connecting the point and the origin in the front view and the mapping reference axis (vertical axis), (X i , Y i , Z i ) is the coordinate of the leaf in the entire three-dimensional space.

[0062] Beneficial Effects

[0063] The present invention proposes a parametric design method for torque converter blades that integrates catenary and cycloid, and innovatively applies catenary and cycloid to blade design. By using the catenary to construct the blade's skeleton and applying the cycloid to design the blade's thickness distribution curve, the blade shape is fully parameterized, which facilitates the precise design of the blade. In addition, this method overcomes the limitations of traditional blade design in terms of curvature continuity and flexibility, significantly broadens the adjustable performance range of the torque converter, and improves the transmission efficiency and power density of the torque converter. Through the precisely designed blade shape, the flow loss in the impeller flow channel is reduced, the service life of the blade is extended, and strong support is provided for the high-performance development of the torque converter.

[0064] (1) Ensure the continuity of the blade profile curve: The present invention uses two catenary segments to construct the blade skeleton, and the two catenary segments are butted at the horizontal tangent to ensure the smoothness of the splicing curve. At the same time, the vertical characteristics of the tangents and the horizontal line of the two cycloid segments at the starting and ending points of the curve are utilized to avoid the "sharp corner" problem in the traditional blade thickness distribution and ensure the continuity of the blade thickness distribution curve. This continuity helps to reduce the hydraulic loss caused by the flow of hydraulic transmission oil in the impeller flow channel, thereby improving the power density and transmission efficiency of the hydraulic torque converter.

[0065] (2) Flexible blade structure and wide adjustable range: By changing parameters such as the blade inlet angle, outlet angle, the location of the joint point of the blade inlet and outlet curves, the thickness peak position and peak height, the direction of the catenary and cycloid can be flexibly adjusted, thereby achieving precise adjustment of the blade curve. This construction method makes the blade adjustment range wide, so as to better adapt to various working conditions and performance requirements, and improve the transmission performance of the torque converter.

[0066] (3) The design method is intuitive and reliable, improving the accuracy and reliability of the design: By superimposing the thickness of the unit blade bone line in the normal direction, the two-dimensional unit blade profile curve (including the pressure surface curve and the suction surface curve) can be obtained. Subsequently, the two-dimensional unit blade profile is scaled, rotated, mirrored, etc. to obtain the two-dimensional real blade profile. The full parametric expression of the blade profile makes precise design simple. This method effectively reduces the uncertainty and error in the design process.

[0067] (4) Shorten the design cycle of the torque converter and promote the market competitiveness of the torque converter in the field of engineering machinery: The characteristic that the tangent of the cycloid at the starting and ending points is perpendicular to the horizontal line can effectively avoid the "sharp corner" defects of the leading and trailing edges of the blades, thereby significantly reducing stress concentration, improving the feasibility of blade casting, and extending the service life of the blades. In addition, by combining the catenary and cycloid design parameters with the key parameters of the torque converter blades, the blade shape design can be completed quickly, significantly shortening the design cycle. This not only improves the design efficiency and power density of the torque converter, but also enhances the market competitiveness of the torque converter in the field of engineering machinery.

[0068] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their description are used to explain the present invention but do not constitute a limitation of the present invention.

[0070] Figure 1 Parametric construction process for torque converter blades;

[0071] Figure 2 Designed for torque converter circulation circle;

[0072] Figure 3 Design of blade skeleton for two-dimensional unit of torque converter;

[0073] Figure 4 Design of thickness distribution of two-dimensional unit blades for torque converter;

[0074] Figure 5 It is the two-dimensional unit blade structure of the torque converter (unit blade bone line, blade thickness distribution curve and thickness superposition);

[0075] Figure 6 Design of real 2D blades for torque converter (scaling, rotation, mirroring);

[0076] Figure 7 Design of the outer ring blade shape of the three-dimensional turbine of the torque converter;

[0077] Figure 8 It is a three-dimensional turbine blade entity of the torque converter;

[0078] Among them: 1-circular outer ring curve, 2-circular inner ring curve, 3-first catenary, 4-second catenary, 5-blade unit skeleton, 6-first cycloid, 7-second cycloid, 8-unit thickness distribution curve, 9-unit blade pressure surface curve, 10-unit blade suction surface curve, 11-real blade pressure surface curve, 12-real blade suction surface curve. DETAILED DESCRIPTION

[0079] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0080] Example

[0081] like Figures 1 to 8 As shown: This embodiment provides a parameterized design method for a torque converter blade, specifically a parameterized design method for a torque converter blade that integrates a catenary and a cycloid. The core content of this design method is: first, the three-arc method is used to accurately draw the cyclic circular curve of the torque converter, including the outer ring, the inner ring curve, and the blade inlet and outlet edge straight lines; then, by giving the blade shape control parameters (blade inlet angle β1, blade outlet angle β2, blade inlet and outlet segment curve splicing point position (in the present invention, p (p>0) is used for control), blade thickness peak position x hmax and the blade thickness peak height h max ), establish the relationship between the blade shape control parameters and the catenary and cycloid curves, and perform parametric design of the unit blade skeleton and blade thickness distribution curve; then, by deriving the unit blade skeleton and superimposing the thickness, the suction surface and pressure surface curves of the unit blade are generated to achieve the two-dimensional unit blade curve design; finally, the real two-dimensional blade curve is obtained by scaling, rotating and mirroring the two-dimensional unit blade curve, and a real three-dimensional blade model is generated through steps such as generalized conformal transformation and ruled surface construction. Finally, the shaping design of the three-dimensional blade model is achieved by adjusting the blade shape control parameters.

[0082] Since all impellers are designed using this method, the following only takes the design of turbine blades as an example. Figure 1 The method of designing torque converter blades by integrating catenary and cycloid is specifically introduced and described in detail.

[0083] The present embodiment proposes a method for parameterized design of a hydraulic torque converter blade that combines a catenary and a cycloid, which may specifically include the following steps 1 to 5.

[0084] Step 1: Design of torque converter circulation circle (such as Figure 2 shown).

[0085] Given the design parameters of the torque converter circulation circle curve, including the known torque converter effective diameter D and minimum diameter d0, the three-arc method can be used to obtain the radii r1 and r3 of the first and third arcs of the outer ring of the circulation circle, and the centers of the first and third arcs are on the symmetric center line, and then the second arc can be obtained based on its tangency with the first and third arcs:

[0086]

[0087] The radius, center and center angle of the three arcs can be easily obtained, and the torque converter circulation circle can be designed. The specific method can be found in the literature [Wang Yan, Wang Yupeng, Ma Wenxing; Comprehensive description and derivative correction method of torque converter circulation circle, Journal of Jilin University (Engineering Edition), 32(1):79-82, 2002].

[0088] Step 2: Unit blade skeleton design.

[0089] Given the design parameters of the unit blade skeleton of the torque converter, the blade inlet and outlet angles β1 and β2 are given, and then the unit blade skeleton is spliced ​​and constructed through two catenary segments.

[0090] The equation of the catenary can be expressed as:

[0091]

[0092] Among them, a is the shape factor of the catenary. The catenary curve is a curve that is symmetrical about the ordinate and passes through the first and second quadrants and the origin. The first catenary determines the value of the shape factor a1 according to the blade inlet angle β1, and the second catenary determines the value of the shape factor a2 according to the blade outlet angle β2. Then, the position of the parameter p is used to control the blade bone line peak. The two catenary segments are spliced ​​at the origin to form a reference bone line, and then the unit blade bone line (such as Figure 3 shown).

[0093] The first catenary equation can be preliminarily obtained from the catenary equation. The first catenary of the present invention selects the curve in the second quadrant and controls its horizontal coordinate with the parameter p-1, that is, the range of the horizontal coordinate is [p-1, 0]. Then, the parameter a1 of the leading edge catenary is controlled according to the relationship between the inlet angle β1 of the torque converter blade and the slope of the tangent at the starting point of the leading edge catenary, and the first catenary equation can be obtained. The known conditions are:

[0094]

[0095] Similarly, the second catenary equation can be preliminarily obtained from the catenary equation. The second catenary of the present invention selects the curve in the first quadrant and controls its horizontal coordinate with the parameter p, that is, the range of the horizontal coordinate is [0, p]. Then, the parameter a2 of the second catenary is controlled according to the relationship between the outlet angle β2 of the torque converter blade and the slope of the tangent at the dead point of the second catenary, and the second catenary equation can be obtained. The known conditions are:

[0096]

[0097] By combining formulas (3) and (4), we can get a spliced ​​reference blade bone line, and then translate the whole blade along the positive direction of the horizontal axis by a distance of 1-p to get the unit blade unit bone line:

[0098]

[0099] Step 3: Design of unit blade thickness.

[0100] The thickness distribution of the unit blade adopts a two-segment cycloid structure. The cycloid equation is:

[0101]

[0102] Among them, ρ is the radius of the rolling circle, which determines the size of the cycloid. The larger the ρ value, the smoother the leading and trailing edges of the constructed blades. t is the rolling angle. Sint and cost are sine and cosine functions, respectively, which describe the position change of the fixed point on the circle relative to the center of the circle in the cycloid equation. The first segment of the cycloid is selected in the present invention as [0, π], and the second segment of the cycloid is selected as [π, 2π]. The ordinates are adjusted by scaling so that the ordinate values ​​of the two segments of the cycloid at t = π are h max Then adjust the horizontal coordinate by scaling and translating so that the horizontal coordinate of the spliced ​​curve has a value range of [0, 1], and the unit leaf thickness distribution curve can be obtained (such as Figure 4 shown).

[0103] The equation of the first cycloid is as follows:

[0104]

[0105] Among them, k x1 , k h1 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf.

[0106] The equation of the second cycloid is as follows:

[0107]

[0108] Among them, k x2 , kh2 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf.

[0109] The tangent line at the starting point of the first cycloid has the following relationship:

[0110]

[0111] The relationship between the end point of the first cycloid and the starting point of the second cycloid is as follows:

[0112]

[0113] The tangent line at the dead point of the second cycloid has the following relationship:

[0114]

[0115] Step 4: Superimposing the thickness of the obtained unit blade bone line can obtain the suction surface curve and pressure surface curve of the unit blade. The slope of each point on the bone line can be obtained by taking the derivative of the bone line. The normal direction of each point on the bone line can be obtained by using the perpendicular relationship between the tangent line and the normal line. The thickness can be superimposed on the normal line to obtain the coordinates of the suction surface and pressure surface of the unit blade;

[0116] First, the tangent slope θ of each point on the bone line can be obtained by taking the derivative of the bone line. According to the geometric relationship, the angle θ between the normal line at each point on the bone line and the positive direction of the x-axis can be obtained. Finally, the thickness is superimposed on the normal line to obtain the suction surface and pressure surface coordinates of the unit blade (such as Figure 5 The known conditions are:

[0117]

[0118] Where θ is the angle between the tangent line of each point of the bone line and the X axis; y c is the ordinate of the unit leaf bone line, h is the ordinate of the unit leaf thickness distribution curve, (x u ,y u ) is the pressure surface coordinate of the unit blade; (x d ,y d ) is the suction surface coordinate of the unit blade.

[0119] Step 5: Scale, mirror and rotate the suction surface and pressure surface curves of the unit blade to obtain the real two-dimensional blade curve (such as Figure 6 shown).

[0120]

[0121] Among them, (S u , L u ) is the real two-dimensional blade pressure surface coordinate, (S d , Ld ) is the coordinate of the real two-dimensional blade suction surface, L is the length of the inner and outer ring curves intercepted by the inlet and outlet edges of the blade on the circulation circle, is the rotation angle.

[0122] After generalized conformal transformation mapping, the corresponding relationship between the two-dimensional blade outer ring coordinates and the three-dimensional coordinates is (such as Figure 7 shown):

[0123]

[0124] Among them, R i Represents the R coordinate (i.e., ordinate) of the corresponding point in the circular view, θ i It represents the angle between the line connecting the point and the origin in the front view and the mapping reference axis (vertical axis), (X i , Y i , Z i ) is the coordinate of the blade in the entire three-dimensional space, and then the three-dimensional blade entity is generated through operations such as ruled stitching (such as Figure 8 shown).

[0125] Finally, it should be noted that this article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only to help understand the core idea of ​​the present invention. Without departing from the principles of the present invention, the present invention may also be improved and modified, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A parametric design method for hydraulic torque converter blades integrating catenary and cycloid, characterized in that: The catenary and cycloid are used to perform parameterized design of blade bone line and blade thickness distribution curve respectively. For the unit blade bone line, the relationship between the unit blade bone line parameters and the catenary is established. According to the unit blade thickness distribution curve, the relationship between the blade thickness distribution curve parameters and the cycloid is established; by changing the blade profile control parameters, the directions of the catenary and the cycloid are controlled, and finally the precise adjustment of the blade profile curve is achieved.

2. The method for parameterized design of hydraulic torque converter blades integrating catenary and cycloid according to claim 1, characterized in that: The following steps are involved: Step 1: Given the design parameters of the torque converter circulation circular curve, the torque converter circulation circular curve is obtained by the three-arc method. The torque converter circulation circular curve includes outer ring, inner ring streamlines and inlet and outlet edge straight lines; Step 2: Given the design parameters of the torque converter unit blade skeleton, first give the blade inlet and outlet angles β1 and β2, and then construct the unit skeleton through two catenary segments; Step 3: Given the torque converter unit blade thickness distribution parameters, the unit blade thickness distribution is constructed through two cycloids; Step 4: The suction surface and pressure surface curves of the unit blade can be obtained by superimposing the thickness of the obtained unit blade bone line. The slope of each point on the bone line can be obtained by taking the derivative of the bone line. The normal direction of each point on the bone line can be obtained by using the perpendicular relationship between the tangent line and the normal line. The suction surface and pressure surface coordinates of the unit blade can be obtained by superimposing the thickness on the normal line. Step 5: Scale, mirror and rotate the suction surface and pressure surface curves of the unit blade to obtain a real two-dimensional blade, and then obtain a real three-dimensional blade through generalized conformal transformation mapping. Finally, construct straight lines and sew to generate a three-dimensional blade.

3. The method for parameterized design of hydraulic torque converter blades integrating catenary and cycloid according to claim 2, characterized in that: The specific process of step 1 is: The circulation circle is designed by the three-arc design method. Among the three arcs, the centers of the first and third arcs are on the symmetric center line. The second arc can be obtained from the first and third arcs according to the tangency. From the known effective diameter D and minimum diameter d0 of the torque converter, the radii r1 and r3 of the first and third arcs of the outer ring of the circulation circle and the width B of the circulation circle can be obtained, and the circulation circle can be designed accordingly:

4. The method for parameterized design of hydraulic torque converter blades integrating catenary and cycloid according to claim 2, characterized in that: The specific process of step 2 is: The unit blade skeleton is constructed by splicing two catenary segments; the equation of the catenary can be expressed as: Where a is the shape factor of the catenary; the first catenary can determine the value of the shape factor a1 according to the blade inlet angle β1, and the second catenary can determine the value of the shape factor a2 according to the blade outlet angle β2, and then the position of the parameter p (p>0) is used to control the blade bone line peak; the two catenary segments are spliced ​​at the origin to form a reference bone line, and then the unit blade bone line can be obtained by moving; Based on the catenary principle, the two-segment catenary equations of the blade skeleton are preliminarily obtained. The first catenary is selected as its curve in the second quadrant, and its horizontal coordinate is controlled by the parameter p-1, that is, the range of the horizontal coordinate is [p-1, 0]; the second catenary is selected as its curve in the first quadrant, and its horizontal coordinate is controlled by the parameter p, that is, the range of the horizontal coordinate is [0, p]; then, according to the relationship between the inlet and outlet angles β1 and β2 of the torque converter blade and the tangent slopes at the starting and ending points of the two catenary segments, and the relationship between the ending point of the first catenary segment and the starting point of the second catenary segment, the shape factor a of the two catenary segments can be obtained. The equation of the first catenary segment is as follows: The equation of the second catenary segment is as follows: The relationship between the tangent line at the starting point of the first catenary segment and the blade inlet angle is as follows: The end points of the first catenary segment and the starting points of the second catenary segment are: The relationship between the tangent line at the dead point of the second catenary segment and the blade outlet angle is as follows: Splice the first and second catenary segments, and then move them to get the unit blade skeleton equation:

5. The method for parameterized design of hydraulic torque converter blades integrating catenary and cycloid according to claim 2, characterized in that: The specific process of step 3 is: The thickness distribution of the unit blade is constructed using two cycloids; the cycloid equation is: Among them, ρ is the radius of the rolling circle, which determines the size of the cycloid. The larger the ρ value, the smoother the leading and trailing edges of the constructed blades. t is the rolling angle. Sint and cost are sine and cosine functions, respectively. They describe the position change of the fixed point on the circle relative to the center of the circle in the cycloid equation. The range of t for the first cycloid is [0, π], and the range of t for the second cycloid is [π, 2π]. The ordinates are adjusted by scaling so that the ordinate values ​​of the two cycloids at t = π are h max Then adjust the horizontal coordinate by scaling and translating so that the horizontal coordinate of the spliced ​​curve has a value range of [0, 1], and the unit leaf thickness distribution curve can be obtained; The equation of the first cycloid is as follows: Among them, k x1 , k h1 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf. The equation of the second cycloid is as follows: Among them, k x2 , k h2 is the scaling factor of the horizontal and vertical axes, h max is the maximum thickness of the unit leaf. The tangent line at the starting point of the first cycloid has the following relationship: The relationship between the end point of the first cycloid and the starting point of the second cycloid is as follows: The tangent line at the dead point of the second cycloid has the following relationship:

6. The parameterized design method for hydraulic torque converter blades integrating catenary and cycloid according to claim 2, characterized in that: The specific process of step 4 is: First, the tangent slope θ of each point on the bone line can be obtained by differentiating the bone line. According to the geometric relationship, the angle θ between the normal line at each point on the bone line and the positive direction of the x-axis can be obtained. Finally, the thickness is superimposed on the normal line to obtain the coordinates of the suction surface and pressure surface of the unit blade; the equations for derivation and thickness superposition are: Where θ is the angle between the tangent line of each point of the bone line and the x-axis; y c is the ordinate of the unit leaf bone line, h is the ordinate of the unit leaf thickness distribution curve, (x u ,y u ) is the pressure surface coordinate of the unit blade; (x d ,y d ) is the suction surface coordinate of the unit blade.

7. The method for parameterized design of hydraulic torque converter blades integrating catenary and cycloid according to claim 2, characterized in that: The specific process of step 5 is: The pressure surface and suction surface curves of the unit blade are scaled, rotated and mirrored to obtain the real two-dimensional blade shape curve; the specific formula is expressed as: Among them, (S u , L u ) is the real two-dimensional blade pressure surface coordinate, (S d , L d ) is the coordinate of the real two-dimensional blade suction surface, L is the length of the inner and outer ring curves intercepted by the inlet and outlet edges of the blade on the circulation circle, is the rotation angle; After generalized conformal transformation mapping, the corresponding relationship between the coordinates of the inner and outer rings of the two-dimensional blade and the three-dimensional coordinates is: Among them, R i Represents the R coordinate of the corresponding point in the circular view, θ i Indicates the angle between the line connecting the point and the origin in the front view and the mapping reference axis, (X i , Y i , Z i ) is the coordinate of the leaf in the entire three-dimensional space.

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