Turbine blade parameterization design and modeling method and system and storage medium

Abstract

The invention relates to the technical field of turbine blade design, and particularly discloses a turbine blade parameterization design and modeling method and system and a storage medium, and the method comprises the steps: determining a quantitative parameter value corresponding to each quantitative structure parameter of a turbine two-dimensional blade type and a plurality of variable parameter values corresponding to each variable structure parameter, generating a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values comprises a quantitative parameter value corresponding to each quantitative structure parameter and any variable parameter value corresponding to each variable structure parameter; screening and determining a target blade profile function expression from all the first blade profile function expressions; and according to the target blade profile function expression, a target turbine three-dimensional blade model is constructed. According to the method, turbine blade parameters can be optimized, turbine blade types with better hydraulic performance parameters under the same size requirement are designed, three-dimensional model establishment is completed, and the design quality and efficiency are improved.

Description

Background Art

[0002] At present, in the oil drilling industry, turbines are mainly used as downhole power drilling tools to provide kinetic energy for the drill bit during drilling operations. The shape of turbine stator and rotor blades is the core content of turbine design work, and the structural parameters of the blades have a great influence on the hydraulic performance of the turbine. The traditional blade design method is to use the target hydraulic performance parameters as design parameters, derive the calculation formula based on knowledge such as fluid mechanics, and complete the calculation of the blade geometric structure parameters. This design method cannot optimize the blade type parameters. The goal of this design method is to design a blade type that meets the design requirements, rather than to select a blade type with better hydraulic performance parameters within a limited geometric size space. This is very unfavorable for the turbine blade design of turbine-type rotary guide shoe tools with relatively small turbine size space.

[0003] Therefore, it is urgent to provide a technical solution to solve the above problems. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a turbine blade parametric design and modeling method, system and storage medium.

[0005] In a first aspect, the present invention provides a parametric design and modeling method for turbine blades, the technical solution of the method is as follows:

[0006] Determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter;

[0007] Screening and determining a target blade profile function expression from all first blade profile function expressions;

[0008] According to the target blade profile function expression, a target turbine three-dimensional blade model is constructed.

[0009] The beneficial effects of the turbine blade parameterized design and modeling method of the present invention are as follows:

[0010] The method of the present invention can optimize turbine blade parameters, design a turbine blade type with better hydraulic performance parameters under the same size requirements, and complete the establishment of a three-dimensional model, thereby improving design quality and efficiency.

[0011] On the basis of the above scheme, the parameterized design and modeling method of turbine blades of the present invention can be further improved as follows.

[0012] In an optional manner, the first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression; the step of generating the first blade profile function expression corresponding to each group of parameter values ​​includes:

[0013] Based on the quintic polynomial, an initial suction surface curve expression and an initial pressure surface curve expression are determined, and according to each group of parameter values, a first suction surface curve expression and a first pressure surface curve expression corresponding to each group of parameter values ​​are generated.

[0014] In an optional manner, the step of screening and determining a target blade profile function expression from all first blade profile function expressions includes:

[0015] Calculate the first curve curvature and the first curvature derivative of the first suction surface curve expression in each first blade profile function expression respectively, and calculate the second curve curvature and the second curvature derivative of the first pressure surface curve expression in each first blade profile function expression respectively, and determine the second blade profile function expression from the first blade profile function expression that meets the first preset condition;

[0016] According to the second suction surface curve expression and the second pressure surface curve expression in each second blade profile function expression, respectively calculate the blade flow channel width corresponding to each second blade profile function expression, and determine the second blade profile function whose blade flow channel width meets the second preset condition as the third blade profile function expression;

[0017] The theoretical torque value corresponding to each third blade profile function expression is calculated, and the third blade profile function expression with the largest theoretical torque value is determined as the target blade profile function expression.

[0018] In an optional manner, the first preset condition is: the first curve curvature is continuous and has the same sign, the sign of the first curvature derivative does not change more than once, the second curve curvature is continuous and changes its sign no more than once, and the sign of the second curve derivative does not change more than once.

[0019] In an optional manner, the second preset condition is that the blade flow channel width from the leading edge to the trailing edge continuously shrinks, and the minimum flow channel width is not less than 5 mm.

[0020] In an optional manner, the step of constructing a target turbine three-dimensional blade model according to the target blade profile function expression includes:

[0021] Constructing a two-dimensional blade profile sketch according to a target suction surface curve expression and a target pressure surface curve expression in the target blade profile function expression;

[0022] Based on the two-dimensional blade profile sketch, a plurality of cross-sectional surfaces are constructed, and all the cross-sectional surfaces are stitched together to obtain the target turbine three-dimensional blade model.

[0023] In an optional manner, multiple quantitative structural parameters include: blade height, stator and rotor leading edge cone angle, stator and rotor trailing edge cone angle, leading edge radius and trailing edge radius; multiple variable structural parameters include: stator and rotor outlet structural angle, stator and rotor inlet structural angle and stator and rotor installation angle.

[0024] In a second aspect, the present invention provides a turbine blade parametric design and modeling system, the technical solution of which is as follows:

[0025] Includes: data processing module, parameter design module and model building module;

[0026] The data processing module is used to: determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter;

[0027] The parameter design module is used to: select and determine a target blade profile function expression from all first blade profile function expressions;

[0028] The model building module is used to build a target turbine three-dimensional blade model according to the target blade profile function expression.

[0029] The beneficial effects of a turbine blade parametric design and modeling system of the present invention are as follows:

[0030] The system of the present invention can optimize turbine blade parameters, design a turbine blade type with better hydraulic performance parameters under the same size requirements, and complete the establishment of a three-dimensional model, thereby improving design quality and efficiency.

[0031] Based on the above solution, the turbine blade parametric design and modeling system of the present invention can also be improved as follows.

[0032] In an optional manner, the first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression; the data processing module is used for:

[0033] Based on the quintic polynomial, an initial suction surface curve expression and an initial pressure surface curve expression are determined, and according to each group of parameter values, a first suction surface curve expression and a first pressure surface curve expression corresponding to each group of parameter values ​​are generated.

[0034] In a third aspect, the present invention provides a storage medium with the following technical solution:

[0035] The storage medium stores instructions, and when a computer reads the instructions, the computer executes the steps of a turbine blade parameterized design and modeling method according to the present invention.

[0036] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings:

[0038] Figure 1 A schematic flow chart of an embodiment of a turbine blade parameterized design and modeling method of the present invention;

[0039] Figure 2 A schematic diagram of the geometric structure parameters of the two-dimensional turbine blade type;

[0040] Figure 3 It is a schematic diagram of the position relationship of each point in the plane rectangular coordinate system;

[0041] Figure 4 It is a schematic diagram of the curved surface of the cross section at the blade root, the mid-diameter and the blade tip;

[0042] Figure 5 is a schematic diagram of a target turbine three-dimensional blade model;

[0043] Figure 6 This is the interface diagram of the calculation program written based on the Matlab GUI module;

[0044] Figure 7 The diagram is a schematic structural diagram of an embodiment of a turbine blade parametric design and modeling system of the present invention. DETAILED DESCRIPTION

[0045] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0046] Figure 1 FIG. 2 is a flow chart showing an embodiment of a turbine blade parameterized design and modeling method provided by the present invention. Figure 1 As shown, the following steps are included:

[0047] S1. Determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each set of parameter values. Where:

[0048] ① The number of geometric structure parameters of the turbine two-dimensional blade type is multiple. Figure 2 As shown, the geometric structure parameters specifically include: blade height b, blade chord length s, blade spacing t, stator and rotor installation angle β m 、Stator inlet structural angle α 2k , stator outlet structural angle α 1k , rotor inlet structural angle β 1k , rotor outlet structural angle β 2k , stator and rotor leading edge cone angle φ1, stator and rotor trailing edge cone angle φ2, leading edge radius r1 and trailing edge radius r2.

[0049] ② The blade height b determines the height of the stator and rotor blades, affecting the height of the single-stage turbine. The value of the blade height b is related to the turbine installation space and is determined by the turbine design parameters. The blade chord length s is determined by the blade height b and the stator and rotor installation angle β m The blade spacing t is independent of the blade profile design and is calculated based on the number of blades after the turbine design is completed. The stator and rotor leading edge cone angle φ1, stator and rotor trailing edge cone angle φ2, leading edge radius r1, trailing edge radius r2, these four parameters take certain values ​​within the empirical range; stator and rotor installation angle β m 、Stator inlet structural angle α 2k , stator outlet structural angle α 1k , rotor inlet structural angle β 1k , rotor outlet structural angle β 2k ,These five parameters are the main design parameters and should take a reasonable value range.

[0050] ③ Multiple quantitative structural parameters include: blade height b, stator rotor leading edge cone angle φ1, stator rotor trailing edge cone angle φ2, leading edge radius r1 and trailing edge radius r2. Multiple variable structural parameters include: stator rotor outlet structural angle (stator outlet structural angle α 1k and rotor outlet structural angle β 2k ), stator and rotor inlet structural angle (stator inlet structural angle α 2k and rotor inlet structural angle β 1k ) and stator and rotor installation angle β m .

[0051] ④ A quantitative structural parameter corresponds to a quantitative parameter value, and a variable structural parameter corresponds to multiple variable parameter values. Multiple values ​​are selected at equal intervals within the value range corresponding to a variable structural parameter as multiple variable parameter values ​​of the variable structural parameter.

[0052] ⑤ Any set of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter.

[0053] ⑥ Each group of parameter values ​​corresponds to a first blade profile function expression. The first blade profile function expression is: a two-dimensional function expression used to characterize the two-dimensional blade profile of the turbine.

[0054] S2. Screen and determine a target blade profile function expression from all first blade profile function expressions. Where:

[0055] The target blade profile function expression is the optimal blade profile function expression.

[0056] S3. Construct a target turbine three-dimensional blade model according to the target blade profile function expression.

[0057] in:

[0058] The target turbine three-dimensional blade model is: a turbine blade three-dimensional model with optimal hydraulic performance in a small space.

[0059] Preferably, the first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression.

[0060] The step of generating a first blade profile function expression corresponding to any set of parameter values ​​comprises:

[0061] Based on the fifth-order polynomial, the initial suction surface curve expression and the initial pressure surface curve expression are determined, and according to each group of parameter values, the first suction surface curve expression and the first pressure surface curve expression corresponding to each group of parameter values ​​are generated. Among them:

[0062] ① Based on the fifth-order polynomial, the process of determining the initial suction surface curve expression is as follows:

[0063] 1) If Figure 3 As shown in the rectangular coordinate system, the turbine two-dimensional blade profile is represented by four curves: the leading edge arc C1, the trailing edge arc C2, the pressure surface curve y A , suction surface curve y B ; The pressure surface curve y A , suction surface curve y B It can be represented by a quintic polynomial function. The general expression of the quintic polynomial is:

[0064] y=a0+a1x+a2x 2 +a3x 3 +a4x 4 +a5x 5 (1)

[0065] Where y is the ordinate, x is the abscissa; a0, a1, a2, a3, a4, a5 are the coefficients of the quintic polynomial;

[0066] Find the first-order derivative of the quintic polynomial:

[0067] y′=a1+2a2x+3a3x 2 +4a4x 3 +5a5x 4 (2)

[0068] The second-order derivative is:

[0069] y″=2a2+6a3x+12a4x 2 +20a5x 3 (3)

[0070] 2) Make the leading edge circle center coincide with the plane rectangular coordinate system, then the leading edge circle center O1 (x1, y1) is the origin of the plane rectangular coordinate system (0, 0), the trailing edge circle center O2 (x2, y2), the leading edge arc and the suction surface curve y B The tangent point is set to A(x A1 ,y A1 ), the leading edge arc C1 and the pressure surface curve y A The tangent point is set to B(x B1 ,y B1 ), the trailing edge arc C2 and the suction surface curve y B The tangent point is set to C(x A2 ,y A2 ), the trailing edge arc C2 and the pressure surface curve y A The tangent point is set to D(x B2 ,y B2 ).

[0071] 3) According to the geometric structure parameters of the turbine two-dimensional blade, the coordinates of each point in the turbine two-dimensional blade are expressed. The coordinate expression of each point is:

[0072] The center of the trailing edge O2(x2,y2):

[0073] x2=x1+b-r1-r2 (4)

[0074] y2=y1+(b-r1-r2)·tanβ m (5)

[0075] Coordinate of starting point of suction surface A(x A1 ,y A1 ):

[0076]

[0077]

[0078] The starting point coordinates of the pressure surface B(x B1 ,y B1 ):

[0079]

[0080]

[0081] Coordinate of the end point of the suction surface C(x A2 ,y A2 ):

[0082]

[0083]

[0084] The end point coordinate of the pressure surface D(x B2 ,y B2 ):

[0085]

[0086]

[0087] 4) Calculate the first-order derivative and second-order derivative of the suction surface curve at points A, B, C, and D. The first-order derivative of each point is the slope of the tangent line at that point, and the second-order derivative of each point is 0, that is:

[0088]

[0089]

[0090]

[0091]

[0092] y″ A1 =y″ A2 =y″ B1 =y″ B2 =0 (18)

[0093] 5) Substitute the coordinates of the two end points A and C of the suction surface curve, as well as the first-order derivative and second-order derivative of the two points into (1), (2) and (3) to obtain:

[0094] y A1 =a0+a1x A1 +a2x A1 2 +a3x A1 3 +a4x A14 +a5x A1 5 (19)

[0095] y A2 =a0+a1x A2 +a2x A2 2 +a3x A2 3 +a4x A2 4 +a5x A2 5 (20)

[0096] y′ A1 =a1+2a2x A1 +3a3x A1 2 +4a4x A1 3 +5a5x A1 4 (twenty one)

[0097] y′ A2 =a1+2a2x A2 +3a3x A2 2 +4a4x A2 3 +5a5x A2 4 (twenty two)

[0098] y″ A1 =2a2+6a3x A1 +12a4x A1 2 +20a5x A1 3 (twenty three)

[0099] y″ A2 =2a2+6a3x A2 +12a4x A2 2 +20a5x A2 3 (twenty four)

[0100] 6) The above equations (19) to (24) are sorted and combined to establish a matrix to obtain the expressions of a0, a1, a2, a3, a4, and a5, and finally the initial suction surface curve expression is constructed. The coordinates of the two end points B and D of the pressure surface curve in step 5) are replaced to construct the initial pressure surface curve expression.

[0101]

[0102] ② According to each set of parameter values, the process of generating the first suction surface curve expression and the first pressure surface curve expression corresponding to each set of parameter values ​​is as follows:

[0103] 1) Input any set of parameter values ​​into the initial suction surface curve expression and the initial pressure surface curve expression respectively to obtain the first suction surface curve expression and the first pressure surface curve expression corresponding to the set of parameter values.

[0104] 2) Repeat 1) to generate the first suction surface curve expression and the first pressure surface curve expression corresponding to each set of parameter values.

[0105] Preferably, S2 includes:

[0106] S21, respectively calculating the first curve curvature and the first curvature derivative of the first suction surface curve expression in each first blade profile function expression, and respectively calculating the second curve curvature and the second curvature derivative of the first pressure surface curve expression in each first blade profile function expression, and determining the second blade profile function expression from the first blade profile function expression that meets the first preset condition. Wherein:

[0107] ① Taking the suction surface as an example, the calculation formula for the first curve curvature of the first suction surface curve expression is:

[0108]

[0109] K is the curvature of the first curve, y′ is the first-order derivative of the first suction surface curve expression, and y″ is the second-order derivative of the first suction surface curve expression. For the first suction surface curve, from the abscissa of point A to the abscissa of point C, a data point is taken at each same small interval, and the first-order derivative and the second-order derivative of the curve at this point are substituted into formula (26) to calculate the curvature of the point. Repeat the calculation to obtain the curvature of all data points of the first suction surface curve expression.

[0110] ② Taking the suction surface as an example, the calculation formula of the first curvature derivative of the first suction surface curve expression is:

[0111]

[0112] Among them, K′ is the first curvature derivative, K1 and K2 are two adjacent data points on the first suction surface curve expression, K1 is the first curve curvature of the previous data point, K2 is the first curve curvature of the next data point; x1 is the horizontal coordinate corresponding to K1, and x2 is the horizontal coordinate corresponding to K2. For the first suction surface curve, the curvature value and horizontal coordinate of the two adjacent data points are substituted into formula (27) to calculate the approximate value of the curvature derivative value of the point, and the curvature derivative of all data points except the last data point can be obtained by repeating the calculation.

[0113] ③ The calculation method of the second curve curvature and the second curvature derivative of the first pressure surface curve expression is the same as that of the first suction surface curve expression, and will not be repeated here.

[0114] ④ The first preset condition is: the curvature of the first curve is continuous and has the same sign, the sign of the derivative of the first curvature changes no more than once, the curvature of the second curve is continuous and changes no more than once, and the sign of the derivative of the second curve changes no more than once.

[0115] S22, according to the second suction surface curve expression and the second pressure surface curve expression in each second blade profile function expression, respectively calculate the blade flow channel width corresponding to each second blade profile function expression, and determine the second blade profile function expression whose blade flow channel width meets the second preset condition as the third blade profile function expression. Wherein:

[0116] ① The blade flow channel width is based on the second pressure surface curve and the second suction surface curve of another blade adjacent to one side of the pressure surface as the boundary. An inscribed circle is drawn in the middle area enclosed by the second pressure surface curve and the second suction surface curve respectively. There is a tangent point with the second pressure surface curve and the second suction surface curve. The diameter of the inscribed circle represents the flow channel width at the current position.

[0117] ② Select a fixed point on the second pressure surface curve, and make a normal line of the second pressure surface curve at this point through this point. Select a moving point on the second suction surface curve of the adjacent blade, and make a normal line of the second suction surface curve at this point through this point. Take the intersection of the two normal lines, and calculate the distance between the intersection and the fixed point, and the distance between the intersection and the moving point respectively. Move the moving point on the second suction surface curve. When the difference in the distance from the intersection to the two points is less than 0.01mm, the intersection can be approximately considered as the center of the inscribed circle, and twice the corresponding distance is the flow channel width at this fixed point on the pressure surface.

[0118] ③ The second preset condition is that the blade flow channel width from the leading edge to the trailing edge of the blade flow channel continuously shrinks, and the minimum flow channel width is not less than 5mm.

[0119] It should be noted that:

[0120] ① Take a number of data points with the same horizontal coordinate difference from the leading edge to the trailing edge on the second pressure surface curve, calculate the flow channel width on the second pressure surface curve in the above manner and draw a chart to determine whether the flow channel width meets the second preset condition.

[0121] ② Before calculating the flow channel width, it is necessary to set the initial value of the number of blades to determine the initial blade spacing t′, calculate the flow channel width and adjust the number of blades. On the premise of meeting the flow channel width requirements, determine the maximum number of blades and calculate the blade spacing t.

[0122] S23, calculating the theoretical torque value corresponding to each third blade profile function expression, and determining the third blade profile function expression with the largest theoretical torque value as the target blade profile function expression. Wherein:

[0123] ①According to the law of conservation of fluid momentum, we can obtain:

[0124]

[0125] Among them, M i is the theoretical torque value of the i-th blade profile function, in N·m; ρ is the fluid density, in kg / m 3 ; c is the axial velocity component of the fluid, unit: m / s; Q i is the volume flow rate corresponding to the i-th blade profile function, in units of: m 3 / s; D is the average diameter, unit: m.

[0126] ② According to formula (28), the greater the difference between the inlet structural angle and the outlet structural angle, the greater the theoretical torque value; in addition, when the installation angle decreases, the theoretical torque value increases. Therefore, firstly, several blade profiles with the smallest installation angle are selected from all the third blade profile function expressions, and then the third blade profile function expression corresponding to the blade profile with the largest difference between the inlet structural angle and the outlet structural angle is selected from several groups of blade profiles with the same installation angle as the target blade profile function expression.

[0127] It should be noted that:

[0128] ① In this embodiment, a set of parameter values ​​corresponding to the target blade profile function expression is shown in Table 1 below.

[0129] Table 1:

[0130] b <![CDATA[β m ]]> <![CDATA[α 2k ]]> <![CDATA[α 1k ]]> <![CDATA[φ1]]> <![CDATA[φ2]]> <![CDATA[r1]]> <![CDATA[r2]]> 12mm 50° 135° 19° 20° 11° 0.7mm 0.4mm

[0131] ②The target blade profile function expression includes:

[0132] 1) The target suction surface curve expression is:

[0133] y A =-1.2202+-1.4265*x+0.0050058*x 2 +0.0064993*x 3 +0.0029643*x 4 +-0.0001732*x 5

[0134] 2) The target pressure surface curve expression is:

[0135] y B=0.85191-0.68035*x-0.050451*x 2 +0.044405*x 3 -0.0031824*x 4 +6.5535*0.00001*x 5

[0136] Preferably, S3 includes:

[0137] S31. Construct a two-dimensional blade profile sketch according to the target suction surface curve expression and the target pressure surface curve expression in the target blade profile function expression.

[0138] Specifically, Figure 4 As shown, the target blade profile function expression is imported into the 3D modeling software, two curves are drawn according to the target suction surface curve expression and the target pressure surface curve expression in the target blade profile function expression, and small circles on the leading edge and the trailing edge are drawn at corresponding positions, and redundant line segments are cut to obtain a 2D blade profile sketch.

[0139] S32. Based on the two-dimensional blade profile sketch, a plurality of cross-sectional surfaces are constructed, and all the cross-sectional surfaces are stitched together to obtain the target turbine three-dimensional blade model.

[0140] Specifically, Figure 5 As shown, the X-axis in the rectangular coordinate system of the plane where the turbine 2D blade is located is used as the axis, and the mid-diameter of the blade is used as the diameter to establish a cylindrical surface, and the 2D blade sketch is projected onto the cylindrical surface, and the surfaces outside the surface surrounded by the curve are cut to obtain the first section surface; the axis is used as the projection axis, and the mid-diameter section is projected at the blade root diameter and the blade tip diameter to draw two section surfaces of the blade (the second section surface and the third section surface). The three section surfaces are stitched and established as entities to complete the establishment of the blade 3D model, and the target turbine 3D blade model is obtained.

[0141] It should be noted that:

[0142] ① The designed turbine stator and rotor blades are mirror images of each other, and the geometric structure parameter values ​​are exactly the same; all the above steps in this embodiment take the design of the turbine stator as an example. After completing the three-dimensional modeling, the two-dimensional blade type sketch is mirrored, and the mirror axis is the X-axis in the plane rectangular coordinate system where the turbine two-dimensional blade type is located. Repeat S32 to complete the establishment of the three-dimensional model of the turbine rotor.

[0143] ② The 3D modeling software is SolidWorks, which can eliminate the problem of small spacing or even overlapping leaves at the root that may be caused by simple sketch stretching modeling methods.

[0144] In addition, the calculation process involved in this embodiment can all be assisted by Matlab programming. This embodiment writes a set of programs based on the Matlab GUI module to complete the above calculation process at one time. Its interface is as follows: Figure 6 As shown, its basic functions include:

[0145] (1) The parameter input panel can be used to input the quantitative parameter values ​​in step 1, and the parameter adjustment panel can be used to adjust the variable parameters in step 1.

[0146] (2) The blade curve function, curve curvature, curvature derivative, and flow channel width can be calculated in sequence. The calculated curve function expression can be output as a table file, the curve curvature and curvature derivative can be output as an image, and the flow channel width value can be output as a list.

[0147] (3) The curvature and flow channel width can be checked and judged, and the judgment results can be directly displayed on the output panel.

[0148] (4) The program has a single calculation function, that is, a calculation is completed by inputting parameters once; it also has a continuous calculation function, that is, the numerical value and image results output can change continuously by adjusting the variable value.

[0149] The technical solution of this embodiment can optimize the parameters of turbine blades, design a turbine blade type with better hydraulic performance parameters under the same size requirements, and complete the establishment of a three-dimensional model, thereby improving the design quality and efficiency.

[0150] Figure 7 FIG. 2 shows a schematic diagram of a turbine blade parameterized design and modeling system according to an embodiment of the present invention. Figure 7 As shown, the system 200 includes: a data processing module 210, a parameter design module 220 and a model building module 230;

[0151] The data processing module 210 is used to: determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter;

[0152] The parameter design module 220 is used to: select and determine a target blade profile function expression from all first blade profile function expressions;

[0153] The model building module 230 is used to build a target turbine three-dimensional blade model according to the target blade profile function expression.

[0154] Preferably, the first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression; the process of generating the first blade profile function expression corresponding to each set of parameter values ​​in the data processing module 210 includes:

[0155] Based on the quintic polynomial, an initial suction surface curve expression and an initial pressure surface curve expression are determined, and according to each group of parameter values, a first suction surface curve expression and a first pressure surface curve expression corresponding to each group of parameter values ​​are generated.

[0156] Preferably, the parameter design module 220 is specifically used for:

[0157] Calculate the first curve curvature and the first curvature derivative of the first suction surface curve expression in each first blade profile function expression respectively, and calculate the second curve curvature and the second curvature derivative of the first pressure surface curve expression in each first blade profile function expression respectively, and determine the second blade profile function expression from the first blade profile function expression that meets the first preset condition;

[0158] According to the second suction surface curve expression and the second pressure surface curve expression in each second blade profile function expression, respectively calculate the blade flow channel width corresponding to each second blade profile function expression, and determine the second blade profile function expression whose blade flow channel width meets the second preset condition as the third blade profile function expression;

[0159] The theoretical torque value corresponding to each third blade profile function expression is calculated, and the third blade profile function expression with the largest theoretical torque value is determined as the target blade profile function expression.

[0160] Preferably, the first preset condition is: the first curve curvature is continuous and has the same sign, the sign of the first curvature derivative does not change more than once, the second curve curvature is continuous and changes its sign no more than once, and the sign of the second curve derivative does not change more than once.

[0161] Preferably, the second preset condition is that the blade flow channel width from the leading edge to the trailing edge shrinks continuously, and the minimum flow channel width is not less than 5 mm.

[0162] Preferably, the model building module 230 is specifically used for:

[0163] Constructing a two-dimensional blade profile sketch according to a target suction surface curve expression and a target pressure surface curve expression in the target blade profile function expression;

[0164] Based on the two-dimensional blade profile sketch, a plurality of cross-sectional surfaces are constructed, and all the cross-sectional surfaces are stitched together to obtain the target turbine three-dimensional blade model.

[0165] Preferably, the multiple quantitative structural parameters include: blade height, stator and rotor leading edge cone angle, stator and rotor trailing edge cone angle, leading edge radius and trailing edge radius; the multiple variable structural parameters include: stator and rotor outlet structural angle, stator and rotor inlet structural angle and stator and rotor installation angle.

[0166] The technical solution of this embodiment can optimize the parameters of turbine blades, design a turbine blade type with better hydraulic performance parameters under the same size requirements, and complete the establishment of a three-dimensional model, thereby improving the design quality and efficiency.

[0167] The above-mentioned parameters and steps for each module to implement corresponding functions in the turbine blade parametric design and modeling system 200 of this embodiment can refer to the parameters and steps in the embodiment of the turbine blade parametric design and modeling method above, and will not be repeated here.

[0168] A storage medium provided by an embodiment of the present invention includes: instructions stored in the storage medium, and when a computer reads the instructions, the computer executes steps such as a parametric design and modeling method for turbine blades. For details, please refer to the various parameters and steps in the embodiment of the parametric design and modeling method for turbine blades in the above text, which will not be repeated here.

[0169] Computer storage media such as USB flash drives, mobile hard disks, etc.

[0170] Those skilled in the art will appreciate that the present invention may be implemented as a method, a system, and a storage medium.

[0171] Therefore, the present invention can be specifically implemented in the following forms, that is, it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), or it can be a combination of hardware and software, which is generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code. Any combination of one or more computer-readable media can be used. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium can be, for example, but not limited to - an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be construed as limiting the present invention, and those skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A parametric design and modeling method for turbine blades, characterized in that: include: Determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter; Screening and determining a target blade profile function expression from all first blade profile function expressions; According to the target blade profile function expression, a target turbine three-dimensional blade model is constructed.

2. The parametric design and modeling method of turbine blades according to claim 1, characterized in that: The first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression; the step of generating the first blade profile function expression corresponding to each group of parameter values ​​includes: Based on the quintic polynomial, an initial suction surface curve expression and an initial pressure surface curve expression are determined, and according to each group of parameter values, a first suction surface curve expression and a first pressure surface curve expression corresponding to each group of parameter values ​​are generated.

3. The parametric design and modeling method of turbine blades according to claim 2, characterized in that: The step of screening and determining a target blade profile function expression from all first blade profile function expressions comprises: Calculate the first curve curvature and the first curvature derivative of the first suction surface curve expression in each first blade profile function expression respectively, and calculate the second curve curvature and the second curvature derivative of the first pressure surface curve expression in each first blade profile function expression respectively, and determine the second blade profile function expression from the first blade profile function expression that meets the first preset condition; According to the second suction surface curve expression and the second pressure surface curve expression in each second blade profile function expression, respectively calculate the blade flow channel width corresponding to each second blade profile function expression, and determine the second blade profile function expression whose blade flow channel width meets the second preset condition as the third blade profile function expression; The theoretical torque value corresponding to each third blade profile function expression is calculated, and the third blade profile function expression with the largest theoretical torque value is determined as the target blade profile function expression.

4. The parametric design and modeling method of turbine blades according to claim 3, characterized in that: The first preset condition is: the first curve curvature is continuous and has the same sign, the sign of the first curvature derivative does not change more than once, the second curve curvature is continuous and the sign changes no more than once, and the sign of the second curve derivative does not change more than once.

5. The turbine blade parametric design and modeling method according to claim 3, characterized in that: The second preset condition is that the blade flow channel width from the leading edge to the trailing edge of the blade flow channel continuously shrinks, and the minimum flow channel width is not less than 5 mm.

6. The parametric design and modeling method of turbine blades according to claim 2, characterized in that: The step of constructing a target turbine three-dimensional blade model according to the target blade profile function expression comprises: Constructing a two-dimensional blade profile sketch according to a target suction surface curve expression and a target pressure surface curve expression in the target blade profile function expression; Based on the two-dimensional blade profile sketch, a plurality of cross-sectional surfaces are constructed, and all the cross-sectional surfaces are stitched together to obtain the target turbine three-dimensional blade model.

7. The parametric design and modeling method for turbine blades according to any one of claims 1 to 6, characterized in that: The multiple quantitative structural parameters include: blade height, stator and rotor leading edge cone angle, stator and rotor trailing edge cone angle, leading edge radius and trailing edge radius; the multiple variable structural parameters include: stator and rotor outlet structural angle, stator and rotor inlet structural angle and stator and rotor installation angle.

8. A parametric design and modeling system for turbine blades, characterized in that: include: Data processing module, parameter design module and model building module; The data processing module is used to: determine the quantitative parameter value corresponding to each quantitative structural parameter of the turbine two-dimensional blade profile and multiple variable parameter values ​​corresponding to each variable structural parameter, and generate a first blade profile function expression corresponding to each group of parameter values; wherein any group of parameter values ​​includes: the quantitative parameter value corresponding to each quantitative structural parameter and any variable parameter value corresponding to each variable structural parameter; The parameter design module is used to: select and determine a target blade profile function expression from all first blade profile function expressions; The model building module is used to build a target turbine three-dimensional blade model according to the target blade profile function expression.

9. The turbine blade parametric design and modeling system according to claim 8, characterized in that: The first blade profile function expression includes: a first suction surface curve expression and a first pressure surface curve expression; the data processing module is used for: Based on the quintic polynomial, an initial suction surface curve expression and an initial pressure surface curve expression are determined, and according to each group of parameter values, a first suction surface curve expression and a first pressure surface curve expression corresponding to each group of parameter values ​​are generated.

10. A storage medium, characterized in that: The storage medium stores instructions, and when a computer reads the instructions, the computer executes the turbine blade parametric design and modeling method according to any one of claims 1 to 7.

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