A method and system for compressor blade angle design

Abstract

The present application relates to axial flow, centrifugal and mixed flow compressor technical field, solve the problem of long time period when the current compressor blade design, specifically for a kind of method and system for compressor blade angle design, blade angle design method includes the following steps: firstly, the chord length of each section of blade profile is normalized to closed interval [0,1];The relative position of blade angle about profile chord length is analyzed, and is recorded as x, the x belongs to [0,1];A plurality of polynomials are established to represent the blade angle distribution form, the corresponding segmented function of the plurality of polynomials in closed interval [0,1] is recorded as f (x), function program is established, a group of series: Q, R, S and T are introduced, f (x) is analyzed and calculated;The coefficients of the polynomial are adjusted to quickly modify the compressor blade angle distribution form.The modification of blade angle distribution form is realized by adjusting the coefficients of the polynomial, and the rapid iteration of compressor blade modeling is realized.

Description

Technical Field

[0001] This invention relates to the field of axial, centrifugal and mixed-flow compressor technology, and in particular to a method and system for compressor blade angle design. Background Technology

[0002] Turbomachinery compresses gas by doing work on it through rotation. Aircraft engine compressors can be classified into multi-stage axial flow, axial flow centrifugal, and mixed flow centrifugal types. They achieve a relatively high pressure ratio by continuously rotating the compressor to compress the gas.

[0003] The gas compression capacity of a single-stage compressor is often determined by the rim work, which is related to the compressor blade angular distribution. Therefore, the compressor blade angular distribution is a key factor determining the compressor's aerodynamic performance. Different compressors have different inlet conditions and load levels, resulting in variations in their blade angular distribution. The compressor blade geometry is obtained by superimposing thickness distributions along the blade's mid-curve. The mid-curve can be obtained by integrating the blade angles along the blade chord. Therefore, the blade angular distribution determines the compressor blade geometry and is one of the core factors in compressor design.

[0004] The distribution of compressor blade angles is often represented by a set of discrete data points. By repeatedly adjusting the discrete points on the blade angle curve, the geometry of the compressor blades can be changed to achieve the design goals. As the requirements for aero-engine power, fuel consumption, and other indicators continue to increase, the aerodynamic load on the compressor also continues to increase, and the geometry of the compressor blades becomes more distorted. In order to more accurately represent the blade angle distribution, a larger number of discrete points are needed; therefore, designing blades with the required geometry requires a longer time cycle.

[0005] Currently, when designing blades for axial, centrifugal, and mixed-flow compressors, the geometric shape of the blades is modified by adjusting the blade angle distribution. However, since blade angles are often represented by one or more sets of discrete data points, and different compressors have different blade angle distributions, completing the design of a compressor blade often requires adjusting a large number of blade angle data points. This adjustment of blade angle data points is labor-intensive and time-consuming, which restricts the development of compressor design technology and the improvement of performance indicators. Therefore, there is an urgent need to propose a method and system for compressor blade angle design to shorten the blade angle design cycle. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method and system for compressor blade angle design. The purpose is to enable the use of polynomials to express the distribution of compressor blade angles, and to shorten the blade angle design cycle by calculating and adjusting the polynomial coefficients. This solves the problem that current compressor blade design requires adjusting a large number of blade angle data points, resulting in a large workload and long time cycle.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for designing compressor blade angles, the method comprising the following steps:

[0008] First, the chord length of each cross-section of the blade is normalized to a closed interval [0, 1].

[0009] Analyze the relative position of the blade angle with respect to the chord length of the leaf shape, and denote it as x, where x∈[0,1];

[0010] Several sets of polynomials are established to represent the leaf angle distribution form. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), where x is the unique independent variable of f(x).

[0011] A function program is established, which introduces a set of numbers: Q, R, S and T, to analyze and calculate f(x) and obtain a new set of coordinates for the blade angle;

[0012] Adjusting the coefficients of the polynomial allows for rapid modification of the compressor blade angular distribution.

[0013] Preferably, the function creation procedure includes the following steps:

[0014] Divide the closed interval [0, 1] into N equal parts to obtain a sequence Q = {Q0, Q1, Q2, ... Q} with N+1 elements. N}={x0, x1, x2, …x N};

[0015] Construct a sequence R = {R0, R1, R2, ... R} N}={0,(f(x0)﹣f(x1)) / (f(x0)﹣f(x N )), (f(x1)﹣f(x2)) / (f(x0)﹣f(x N )), …(f(x) N﹣1 )﹣f(x N )) / (f(x0)﹣f(x N ))};

[0016] Construct a sequence S = {S0, S1, S2, ... S} N}={detaAfa*R(0), detaAfa*R(1),...detaAfa*R(N)}, where detaAfa=Afa in -Afa out Afa in For the inlet angle of the blade, Afa out For the blade exit angle;

[0017] Construct a sequence

[0018] The new blade angle is defined by a set of coordinates (Q). i T i ), i∈[0,N];

[0019] Preferably, the plurality of polynomials includes a plurality of cubic polynomials, and the plurality of cubic polynomials includes two or three cubic polynomials.

[0020] Preferably, the method for representing the blade angular distribution form using the two sets of cubic polynomials includes the following steps:

[0021] Insert a point into the closed interval [0, 1], and let the corresponding value of the point in the closed interval [0, 1] be t. The closed interval [0, 1] is divided into two adjacent intervals by the point.

[0022] For two adjacent intervals, two sets of cubic polynomials are established to represent the distribution of the blade angle.

[0023] Preferably, the two adjacent intervals include: [0, t) and [t, 1], where the value of t is in the range of (0, 1).

[0024] Preferably, the two sets of cubic polynomials are as follows:

[0025] aX 3 +bX 2 +cX+d, where 0≤x﹤t, a, b, c and d are the coefficients of the corresponding polynomial and are variable constants;

[0026] eX 3 +fX 2 +gX+h, where t≤x≤1, e, f, g and h are the coefficients of the corresponding polynomial and are variable constants.

[0027] Preferred, aX 3 +bX 2 +cX+d and eX 3 +fX 2 The piecewise function corresponding to +gX+h is: The f(x) is first-order differentiable at x = t.

[0028] Preferably, the method for implementing the three sets of cubic polynomials representing the blade angular distribution includes the following steps:

[0029] Two points are inserted into the closed interval [0, 1], and the corresponding values ​​of the two points in the closed interval [0, 1] are t1 and t2 respectively. The closed interval [0, 1] is divided into three adjacent intervals by t1 and t2.

[0030] For three adjacent intervals, three sets of cubic polynomials are established to represent the distribution of the blade angle.

[0031] Preferably, the three adjacent intervals include: [0, t1), [t1, t2), [t2, 1], where the values ​​of t1 and t2 are both in the interval (0, 1), and t1 < t2.

[0032] Preferably, the three sets of cubic polynomials are as follows:

[0033] a1X 3 +b1X 2 +c1X+d1, where 0≤x﹤t1, a1, b1, c1 and d1 are the coefficients of the corresponding polynomial and are variable constants;

[0034] e1X 3 +f1X 2 +g1X+h1, where t1≤x<t2, e1, f1, g1 and h1 are the coefficients of the corresponding polynomials and are variable constants;

[0035] k1X 3 +m1X 2 +n1X+q1, where t2≤x≤1, k1, m1, n1 and q1 are the coefficients of the corresponding polynomial and are variable constants.

[0036] Preferred, a1X 3 +b1X 2 +c1X+d1、e1X 3 +f1X 2 +g1X+h1 and k1X 3 +m1X 2 The piecewise function corresponding to +n1X+q1 is: The f(x) is first-order differentiable at x = t1 and x = t2.

[0037] In addition, the present invention also provides a system for compressor blade angle design, the system comprising,

[0038] Data processing unit: used to normalize the chord length of each blade section into a closed interval [0, 1];

[0039] Extracted variable unit: used to analyze the relative position of the blade angle with respect to the blade chord length, and denoted as x, where x∈[0,1];

[0040] Modeling unit: used to establish several sets of polynomials to represent the shape of the blade angle distribution. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), where x is the unique independent variable of f(x).

[0041] Calculation unit: used to establish function program, introduce a set of numbers: Q, R, S and T, analyze and calculate f(x) to obtain a set of coordinates of the new blade angle;

[0042] Fast iteration unit: used to adjust the coefficients of the polynomial to quickly modify the compressor blade angular distribution.

[0043] Preferably, the computational unit includes the following components when creating the function program:

[0044] The first module is used to divide the closed interval [0, 1] into N equal parts to obtain a sequence Q = {Q0, Q1, Q2, ... Q} with N+1 elements. N}={x0, x1, x2, …x N};

[0045] The second module is used to construct the sequence R = {R0, R1, R2, ... R}. N}={0,(f(x0)﹣f(x1)) / (f(x0)﹣f(x N )), (f(x1)﹣f(x2)) / (f(x0)﹣f(x N )), …(f(x) N﹣1 )﹣f(x N )) / (f(x0)﹣f(x N ))};

[0046] The third module is used to construct the sequence S = {S0, S1, S2, ... S}. N}={detaAfa*R(0), detaAfa*R(1),...detaAfa*R(N)}, where detaAfa=Afa in -Afa out Afa in For the inlet angle of the blade, Afa out For the blade exit angle;

[0047] Module 4: Used to construct sequences

[0048] The new blade angle is defined by a set of coordinates (Q). i T i), i∈[0,N].

[0049] Preferably, the modeling unit establishes several sets of polynomials, including several sets of cubic polynomials, wherein the several sets of cubic polynomials include two sets or three sets of cubic polynomials.

[0050] Compared with the prior art, the present invention provides a method and system for compressor blade angle design, which has the following beneficial effects:

[0051] 1. This invention introduces several sets of polynomials to represent the distribution of blade angles. By using the Q, R, S and T series for data processing, a new set of coordinates for the blade angles can be obtained. By adjusting the polynomial coefficients, the distribution of blade angles can be modified, enabling rapid iteration of compressor blade design, improving design efficiency, shortening the time required to complete the design, and facilitating designers' understanding of blade angle design rules and accumulation of relevant knowledge and experience.

[0052] 2. The polynomials used in this invention to represent the angular distribution of compressor blades can generally be set as two sets of cubic polynomials or three sets of cubic polynomials, or as other sets of polynomials of several degrees. Considering factors such as the complexity of the blades involved, the magnitude of the load pressure borne, and the design accuracy, the degree and number of polynomials used can be adjusted.

[0053] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description and the drawings. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the 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 based on these drawings without creative effort.

[0055] Figure 1 The diagram shows the blade angular distribution curve of a certain compressor.

[0056] Figure 2 A schematic diagram of the curve corresponding to the function f(x) according to an embodiment of the present invention is shown;

[0057] Figure 3 A schematic diagram of the compressor blade angular distribution curve mapped according to an embodiment of the present invention is shown. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. 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.

[0059] Please refer to Figure 1 The diagram shows the blade angular distribution curve of a compressor. Currently, axial compressors, centrifugal compressors, and mixed-flow compressors modify the blade geometry by adjusting the blade angular distribution during blade design. The gas compression capacity of a single-stage compressor is often determined by the rim work, which is related to the compressor blade angular distribution. Therefore, the compressor blade angle is a key factor determining the compressor's aerodynamic performance. Different compressors have different inlet conditions and load levels, resulting in differences in the blade angular distribution they employ.

[0060] The angular distribution of compressor blades determines the aerodynamic performance of the compressor. When designing compressor blades, discrete points are often used to represent the blade angular distribution. The chord lengths of each blade section are normalized so that the chord lengths of each section are within the range of 0-1. As shown in the blade angular distribution curve, the blade angle gradually decreases as the relative chord length of the normalized compressor blade increases. By using several discrete points to represent the distribution of blade angles and repeatedly adjusting the discrete points on the blade angular distribution curve, the geometric shape of the compressor blade can be changed to achieve the design goal.

[0061] With the continuous improvement of requirements for aero-engine power, fuel consumption, and other indicators, the aerodynamic load of compressors is also increasing, and the geometry of compressor blades is becoming more distorted. In order to more accurately represent the blade angle distribution, a larger number of discrete points are needed. To complete the design of a compressor blade, it is often necessary to adjust a large number of blade angle data points. The excessively long adjustment cycle of blade angle data points will restrict the development of compressor design technology and the improvement of performance indicators. This invention proposes a method for compressor blade angle design, which uses a polynomial to represent the distribution state of the blade angle. By adjusting the polynomial coefficients, the compressor blade can be modified, enabling rapid iteration of compressor design schemes, improving design efficiency, and shortening the time required for compressor blade design.

[0062] This invention provides a method for designing compressor blade angles. The method includes the following steps: (1) First, normalize the chord length of each blade section to a closed interval [0, 1]; (2) Analyze the relative position of the blade angle with respect to the blade chord length and denote it as x, x∈[0, 1]; (3) Establish several sets of polynomials to represent the blade angle distribution form. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), where x is the unique independent variable of f(x); (4) Establish a function program, introduce a set of sequences: Q, R, S and T, analyze and calculate f(x), and obtain a set of coordinates for the new blade angle; (5) Adjust the coefficients of the polynomials to quickly modify the compressor blade angle distribution form.

[0063] The function program includes the following steps: (1) Divide the closed interval [0, 1] into N equal parts to obtain a sequence Q = {Q0, Q1, Q2, ... Q} with N+1 elements. N}={x0, x1, x2, …x N};(2) Construct a sequence R={R0,R1,R2,…R N}={0,(f(x0)﹣f(x1)) / (f(x0)﹣f(x N )), (f(x1)﹣f(x2)) / (f(x0)﹣f(x N )), …(f(x) N﹣1 )﹣f(x N )) / (f(x0)﹣f(x N ))}, R is a normalized sequence with N+1 elements; (3) Construct the sequence S={S0,S1,S2,…S N}={detaAfa*R(0), detaAfa*R(1),...detaAfa*R(N)}, where detaAfa=Afa in -Afa out Afa in For the blade inlet angle, Afa out (4) Construct a sequence of numbers for the blade exit angle.

[0064] The new set of coordinates for the blade angle is (Q) i T i ), i∈[0,N]; several sets of polynomials including but not limited to several sets of cubic polynomials, and several sets of cubic polynomials including but not limited to two or three sets of cubic polynomials.

[0065] For a typical compressor blade, the distribution of the blade angle can be represented by setting two sets of cubic polynomials. The method of representing the blade angle distribution by two sets of cubic polynomials includes the following steps: (1) Insert a point into the closed interval [0, 1]. The corresponding value of the point in the closed interval [0, 1] is denoted as t. The closed interval [0, 1] is divided into two adjacent intervals by the point; (2) For the two adjacent intervals, establish two different sets of cubic polynomials to represent the distribution of the blade angle. The two adjacent intervals include: [0, t) and [t, 1], where the value range of t is (0, 1).

[0066] The two different cubic polynomials are: aX 3 +bX 2 +cX+d, where 0≤x<t, a, b, c, and d are the coefficients of the corresponding polynomial and are variable constants; eX 3 +fX 2 +gX+h, where t≤x≤1, and e, f, g, and h are the coefficients of the corresponding polynomial, and are variable constants. aX 3 +bX 2 +cX+d and eX 3 +fX 2 The piecewise function corresponding to +gX+h is: f(x) is first-order differentiable at x = t, that is, at x = t, f(t) = f(t). - )=f(t + And the left derivative of f(x) equals the right derivative, therefore x→t - The slope of the curve containing f(x) is equal to x→t + The slope of the curve containing f(x) is such that the curve is continuous and smooth at x = t.

[0067] In the function f(x), the variable constants a, b, c, d, e, f, g, and h are determined based on a large amount of experimental data and experience from design and production practices in actual calculations. When iterating the design of compressor blade angles, the values ​​of a, b, c, d, e, f, g, and h are adjusted to quickly modify the compressor blade angle distribution.

[0068] Please refer to Figure 2 In the blade angle design process, a, b, c, d, e, f, g, and h can take values ​​of 51.2, -55.3, -19, 57.2, 11.3, 6.4, -50.6, and 62.5 respectively. Then, the interval x∈[0,1] is divided into 20 equal parts, so N=20. This yields a sequence Q={0, 0.05, 0.1, 0.15……1} with N+1 elements. Each element in sequence Q is then substituted as the independent variable of f(x). Where a, b, c, d, e, f, g, and h are respectively taken as 51.2, -55.3, -19, 57.2, 11.3, 6.4, -50.6, and 62.5; the calculated curve coordinates are shown in Table 1.

[0069] Table 1: Coordinate points corresponding to the function curve

[0070]

[0071]

[0072] Table 1 shows 21 coordinate points. A corresponding coordinate curve diagram is drawn based on these 21 coordinate points, as follows: Figure 2 , where x∈[0,1].

[0073] Please refer to Figure 3 Assuming a compressor blade has an inlet angle of 60° and an outlet angle of 40°, map the function curve onto the angular distribution of this compressor blade.

[0074] First, we need to pass (f(x) i )﹣f(x i+1 )) / ((f(x0)﹣f(x N The operation yields a normalized sequence R, where f(x) i ) is x = x i The time corresponds to the function value of f(x), i∈[0,20], and i is an integer;

[0075] R={0,0.0392,0.0478,0.0551,0.0609,0.0654,0.0684,0.0701,0.0704,0.0693,0.066 8,0.0648,0.0580,0.0532,0.0480,0.0426,0.0368,0.0307,0.0243,0.0177,0.0107},

[0076] The sequence S can be obtained by using (60-40)*R(i).

[0077] S={0.0000,0.7839,0.9565,1.1012,1.2181,1.3071,1.3684,1.4018,1.4074,1.3851,1. 3350,1.2963,1.1603,1.0634,0.9604,0.8512,0.7359,0.6145,0.4869,0.3532,0.2133},

[0078] pass The calculation process involves a sequence T, where 1 ≤ l ≤ 20 and l is a positive integer.

[0079] T = {60.0000, 59.2161, 58.2596, 57.1584, 55.9403, 54.6332, 53.2648, 51.8630, 50.4557, 49.0705, 47.7355, 46.4392, 45.2788, 44.2154, 43.2550, 42.4038, 41.6678, 41.0533, 40.5664, 40.2133, 40.0000}, and the coordinates of the new blade angle are shown in Table 2.

[0080] Table 2: Mapped compressor blade angular distribution coordinates

[0081] 0.0000 60.0000 0.0500 59.2161 0.1000 58.2596 0.1500 57.1584 0.2000 55.9403 0.2500 54.6332 0.3000 53.2648 0.3500 51.8630 0.4000 50.4557 0.4500 49.0705 0.5000 47.7355 0.5500 46.4392 0.6000 45.2788 0.6500 44.2154 0.7000 43.2550 0.7500 42.4038 0.8000 41.6678 0.8500 41.0533 0.9000 40.5664 0.9500 40.2133 1.0000 40.0000

[0082] Table 2 shows the coordinates of 21 mapped compressor blade angular distribution points. Based on these 21 coordinate points, a schematic diagram of the corresponding compressor blade angular distribution curves is drawn, as follows: Figure 3 , where x∈[0,1]; after obtaining the new blade angle distribution, the arc of the blade profile can be obtained by integration, and the blade thickness can be superimposed on the obtained arc of the blade profile to obtain the corresponding compressor blade profile.

[0083] For compressor blades subjected to high load pressure, the interval [0, 1] can be further subdivided in the blade angle design. For example, two points can be inserted into the interval [0, 1] to divide it into three smaller intervals. For each smaller interval, three different polynomials are used to represent and calculate the blade angle distribution. The implementation method of representing the blade angle distribution with three sets of cubic polynomials includes the following steps: (1) Insert two points into the closed interval [0, 1]. The corresponding values ​​of the two points in the closed interval [0, 1] are denoted as t1 and t2, respectively. The closed interval [0, 1] is divided into three adjacent intervals by t1 and t2; (2) For the three adjacent intervals, establish three different cubic polynomials to represent the blade angle distribution. The three adjacent intervals include: [0, t1), [t1, t2), and [t2, 1], where the value intervals of t1 and t2 are both (0, 1), and t1 < t2.

[0084] The three different cubic polynomials are: (1) a1X 3 +b1X 2 +c1X+d1, where 0≤x﹤t1, a1, b1, c1 and d1 are the coefficients of the corresponding polynomials and are variable constants; (2)e1X 3 +f1X 2+g1X+h1, where t1≤x<t2, e1, f1, g1 and h1 are the coefficients of the corresponding polynomials and are variable constants; (3)k1X 3 +m1X 2 +n1X+q1, where t2≤x≤1, k1, m1, n1, and q1 are the coefficients of the corresponding polynomial and are variable constants. a1X 3 +b1X 2 +c1X+d1、e1X 3 +f1X 2 +g1X+h1 and k1X 3 +m1X 2 The piecewise function corresponding to +n1X+q1 is:

[0085] f(x) is first-order differentiable at x = t1 and x = t2, f(t1) = f(t1) - )=f(t1 + And f(t2)=f(t2) - )=f(t2 + The curve containing f(x) is continuous and smooth at x = t1 and x = t2. The subsequent calculation process using three sets of cubic polynomials to represent the blade angular distribution is similar to that using two sets of cubic polynomials.

[0086] The present invention also provides a system for compressor blade angle design. The system for blade angle design includes: (1) a data processing unit: used to normalize the chord length of each section of the blade to a closed interval [0, 1]; (2) a variable extraction unit: used to analyze the relative position of the blade angle with respect to the chord length of the blade and denot it as x, x∈[0, 1]; (3) a modeling unit: used to establish several sets of polynomials to represent the blade angle distribution form. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), and x is the unique independent variable of f(x); (4) a calculation unit: used to establish a function program, introduce a set of sequences: Q, R, S and T, analyze and calculate f(x), and obtain a set of coordinates of the new blade angle; (5) a fast iteration unit: used to adjust the coefficients of the polynomials to quickly modify the compressor blade angle distribution form.

[0087] The calculation unit includes the following when establishing the function program: (1) First module: used to divide the closed interval [0, 1] into N equal parts to obtain a sequence Q = {Q0, Q1, Q2, ... Q} with N+1 elements. N}={x0, x1, x2, …x N};(2) Second module: used to construct the sequence R={R0,R1,R2,…R N}={0,(f(x0)﹣f(x1)) / (f(x0)﹣f(x N)), (f(x1)﹣f(x2)) / (f(x0)﹣f(x N )), …(f(x) N﹣1 )﹣f(x N )) / (f(x0)﹣f(x N (3) The third module: used to construct the sequence S = {S0, S1, S2, ... S} N}={detaAfa*R(0), detaAfa*R(1),...detaAfa*R(N)}, where detaAfa=Afa in -Afa out Afa in For the blade inlet angle, Afa out 4) Fourth module: used to construct the sequence.

[0088] The new set of coordinates for the blade angle is (Q) i T i ), i∈[0,N].

[0089] After obtaining the new blade angle distribution through the above calculations, the mid-arc line of the blade profile can be obtained by integration. The corresponding compressor blade profile can be obtained by superimposing the blade thickness on the mid-arc line of the obtained blade profile.

[0090] In the blade angle design method proposed in this invention, the coefficients of the established polynomial are selected based on a large amount of experimental data and experience from design and production practices. The polynomial coefficients are variable constants. When designing compressor blades, the compressor blades can be modified by adjusting the coefficients of the established polynomial, thereby enabling rapid iteration of compressor design, improving design efficiency, and shortening the time required for compressor blade design.

[0091] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for designing compressor blade angles, characterized in that, The method for designing the blade angle includes the following steps: First, the chord length of each cross-section of the blade is normalized to a closed interval [0, 1]. Analyze the relative position of the blade angle with respect to the chord length of the leaf shape, and denote it as x, where x∈[0,1]; Several sets of polynomials are established to represent the leaf angle distribution form. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), where x is the unique independent variable of f(x). The several sets of polynomials include several sets of cubic polynomials, and the several sets of cubic polynomials include two sets or three sets of cubic polynomials. A function program is established, which introduces a set of numbers: Q, R, S, and T, to analyze and calculate f(x) and obtain a new set of coordinates for the blade angle. The establishment of the function program includes the following steps: Dividing the closed interval [0, 1] into N equal parts yields a sequence with N+1 elements: Constructing a sequence: Constructing a sequence: ,in , For the inlet angle of the blade, For the blade exit angle; Constructing a sequence: The new blade angle is defined by a set of coordinates. ; The method also includes: Adjusting the coefficients of the polynomial allows for rapid modification of the compressor blade angular distribution.

2. The method for compressor blade angle design according to claim 1, characterized in that, The method for representing the blade angular distribution using the two sets of cubic polynomials includes the following steps: Insert a point into the closed interval [0, 1], and let the corresponding value of the point in the closed interval [0, 1] be t. The closed interval [0, 1] is divided into two adjacent intervals by the point. For two adjacent intervals, two sets of cubic polynomials are established to represent the distribution of the blade angle.

3. The method for compressor blade angle design according to claim 2, characterized in that, The two adjacent intervals include: [0, t) and [t, 1], where the value of t is in the interval (0, 1).

4. A method for compressor blade angle design according to claim 1 or 2, characterized in that, The two sets of cubic polynomials are as follows: ,in, a, b, c, and d are the coefficients of the corresponding polynomials and are variable constants; ,in, e, f, g, and h are the coefficients of the corresponding polynomials and are variable constants.

5. The method for compressor blade angle design according to claim 4, characterized in that, and The corresponding piecewise function is: The f(x) is first-order differentiable at x=t.

6. The method for compressor blade angle design according to claim 1, characterized in that, The method for representing the blade angular distribution using the three sets of cubic polynomials includes the following steps: Two points are inserted into the closed interval [0, 1], and the corresponding values ​​of the two points in the closed interval [0, 1] are t1 and t2 respectively. The closed interval [0, 1] is divided into three adjacent intervals by t1 and t2. For three adjacent intervals, three sets of cubic polynomials are established to represent the distribution of the blade angle.

7. The method for compressor blade angle design according to claim 6, characterized in that, The three adjacent intervals include: [0, t1), [t1, t2), [t2, 1], where , The values ​​of t1 and t2 are both in the range (0, 1), and t1 < t2.

8. A method for compressor blade angle design according to claim 6, characterized in that, The three sets of cubic polynomials are as follows: ,in, a1, b1, c1, and d1 are the coefficients of the corresponding polynomials and are variable constants; ,in, e1, f1, g1, and h1 are the coefficients of the corresponding polynomials and are variable constants; ,in, k1, m1, n1 and q1 are the coefficients of the corresponding polynomials and are variable constants.

9. A method for compressor blade angle design according to claim 8, characterized in that, , and The corresponding piecewise function is: The f(x) is first-order differentiable at x=t1 and x=t2.

10. A system for compressor blade angle design, characterized in that, The system for blade angle design includes... Data processing unit: used to normalize the chord length of each blade section into a closed interval [0, 1]; Extracted variable unit: used to analyze the relative position of the blade angle with respect to the blade chord length, and denoted as x, where x∈[0,1]; Modeling unit: used to establish several sets of polynomials to represent the leaf angle distribution form. The piecewise function corresponding to the several sets of polynomials in the closed interval [0, 1] is denoted as f(x), where x is the unique independent variable of f(x). The several sets of polynomials established by the modeling unit include several sets of cubic polynomials, and the several sets of cubic polynomials include two sets / three sets of cubic polynomials. Calculation unit: Used to establish a function program, introducing a set of numbers: Q, R, S, and T, analyzing and calculating f(x) to obtain a new set of coordinates for the blade angle. The calculation unit includes the following when establishing the function program: The first module is used to divide the closed interval [0, 1] into N equal parts to obtain a sequence with N+1 elements. ; Module 2: Used to construct sequences. Module 3: Used to construct sequences. ,in , For the inlet angle of the blade, For the blade exit angle; Module 4: Used to construct sequences The new blade angle is defined by a set of coordinates (Q). i T i ), i∈[0,N]; Fast iteration unit: used to adjust the coefficients of the polynomial to quickly modify the compressor blade angular distribution.

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