Method for determining optimal opening value of water guide mechanism of water pump turbine by digital preloading

Abstract

The application discloses a kind of water pump water turbine guide vane digital preloading optimal opening value determination method, it is related to water turbine manufacturing technical field, the optimal opening value determination method provided by the present application is used to water pump water turbine guide vane when digital preloading is analyzed and determined to determine the optimal value of guide vane opening value after adjustment, and used to judge whether guide vane opening value after assembly can meet acceptance requirement.Guide vane is replaced by digital preloading instead of physical preloading, which not only can equally meet the judgment of guide vane assembly quality and the acceptance of key data, but also can greatly reduce energy consumption and compress assembly cycle.In addition, the measured data and model of each component obtained by reverse measurement can be used for comprehensive quality judgment of each component processing and realization of digital twin product.The present application can provide important technical basis and key support for digital preloading of water pump water turbine guide vane to determine assembly quality.

Description

Technical Field

[0001] This invention relates to the field of water turbine manufacturing technology, and more specifically to a method for determining the optimal opening value of the digital pre-installation of the guide vane mechanism of a water pump turbine. Background Technology

[0002] After all components of the water pump turbine's guide vane mechanism are manufactured in the factory, they need to be pre-assembled to verify whether the assembly dimensions and geometric tolerances of each component meet the design and usage requirements. Among these, the opening value of the guide vane's contact plane between the top cover and the bottom ring is a key data point for the pre-assembly acceptance of the guide vane mechanism. Its size affects whether the guide vane can rotate flexibly while minimizing water leakage. Currently, under existing manufacturing technology and models, the guide vane mechanism requires overall physical pre-assembly in the factory, assembling all components such as the top cover, bottom ring, and guide vanes. Then, the opening value between the top cover and bottom ring is measured one by one. Adjustable tooling is used to adjust the support surfaces of the top cover or bottom ring in various directions to find the optimal value for the guide vane opening value, which is then used to determine whether the opening value of the pre-assembled guide vane mechanism meets the design and usage requirements.

[0003] However, with the development of advanced manufacturing technologies, especially digital large-size 3D measurement systems and reverse engineering technology, the water guide mechanism of a pump-turbine can achieve the same assembly quality judgment and pre-assembly acceptance as the physical pre-assembly by accurately reverse 3D measuring the components involved in the pre-assembly and using the reverse modeling data for assembly and calculation. This method can be called the digital pre-assembly technology for the water guide mechanism of a pump-turbine. Digital pre-assembly technology is a cutting-edge development technology in the turbine manufacturing industry, in line with the national dual-carbon strategy and green development concept. Therefore, how to use digital pre-assembly technology to calculate the optimal opening value of the water guide mechanism of a pump-turbine is an urgent problem to be solved. Summary of the Invention

[0004] To overcome the shortcomings of the existing technology, this invention discloses a method for determining the optimal opening value of the digital pre-installation of the guide vane mechanism of a water pump turbine. This invention provides a general method for adjusting the opening value of the guide vane mechanism and calculating the optimal opening data in the digital pre-installation technology of the guide vane mechanism of a water pump turbine. The optimal opening value calculated by this method can achieve the same acceptance conclusion as the physical pre-installation to meet the accurate evaluation of the pre-installation quality of the guide vane mechanism.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for determining the optimal opening value of a pump-turbine guide vane mechanism via digital pre-installation includes the following steps:

[0007] I. Theoretical Pre-installation 3D Model Establishment

[0008] S1. Based on the design dimensions of the top cover and bottom ring, as well as the assembly constraints and design opening values ​​of the water guiding mechanism, establish a theoretical pre-installation three-dimensional model, and obtain the coordinate data of the theoretical measuring points of the top cover and bottom ring opening values ​​in the theoretical pre-installation three-dimensional model;

[0009] In step S1, based on the design dimensions of the top cover and bottom ring, as well as the assembly constraints and design opening values ​​of the water guiding mechanism, a standardized theoretical pre-assembled three-dimensional model of the top cover and bottom ring in the Cartesian coordinate system is established, and the coordinate data of the theoretical measurement points of the opening values ​​of the top cover and bottom ring are obtained in turn.

[0010] Preferably, step S1 includes the following steps:

[0011] S11. Establish three-dimensional models of the top cover and bottom ring respectively based on the design values ​​of the top cover and bottom ring. In the three-dimensional model of the bottom ring, set the center of the leak-stop ring as the origin of the coordinate system, set the line connecting the center of the leak-stop ring and the center of the #1 shaft hole as the +X axis, and set the upward-facing sealing opening plane as the +Z axis to establish a Cartesian coordinate system. Based on the design opening value of the water guiding mechanism and the assembly constraint relationship, assemble the top cover and bottom ring to obtain the theoretical pre-assembled three-dimensional model of the water guiding mechanism opening calculation.

[0012] S12. Assume the water guiding mechanism has N guide vanes. Using the bottom ring sealing and opening plane as the reference plane, let L1 be the perpendicular bisector of the line connecting the centers of guide vane #1 and guide vane #2, and L2 be the center distribution circle of the guide vanes. The intersection of L1 and L2 is the theoretical measuring point #1 for calculating the bottom ring opening value, and its coordinates are... Then, using the origin as the reference point, the remaining theoretical measurement points for the bottom ring are obtained sequentially using a circular array. , ... ;

[0013] S13. Taking the top cover sealing and opening plane as the reference plane, let L3 be the perpendicular bisector of the line connecting the centers of guide vane shaft holes #1 and #2, and L4 be the guide vane center distribution circle. The intersection of L3 and L4 is the theoretical measuring point #1 for calculating the top cover opening value, and its coordinates are: Then, using the origin of the coordinate system as the reference point, the remaining theoretical measurement points for calculating the opening of the top cover are obtained sequentially using a circular array. , ... .

[0014] II. Three-dimensional measurement of the flow surface

[0015] S2. In the physical model after production and processing, the flow surfaces of the top cover and bottom ring are measured in three dimensions to obtain the original measurement data. The measurement data is preprocessed and matched with the theoretical pre-installed three-dimensional model in step S1. Then, based on the coordinate data of the theoretical measurement points in step S1, the basic data of the measured coordinates of the bottom ring and top cover are obtained.

[0016] In step S2, a comprehensive three-dimensional measurement of the flow surfaces of the top cover and bottom ring is performed to obtain the original measurement data. The measurement data is then processed to obtain the basic data that can be used for the next step of optimization calculation.

[0017] Preferably, step S2 includes the following steps:

[0018] S21. In the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the bottom ring flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N1 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N1 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected circle of the leak-stop ring. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ;

[0019] In the above steps, the number of measuring points for the sealing opening plane, the leak-proof ring cylindrical surface, and the No. 1 guide vane shaft hole is ≥3.

[0020] S22. In the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the top cover flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N2 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N2 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected leak-stop ring circle. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ;

[0021] In the above steps, the number of measuring points for the sealing opening plane, the leak-proof ring cylindrical surface, and the No. 1 guide vane shaft hole is ≥3.

[0022] S23. Based on steps S21 and S22, obtain point cloud data of the sealing opening plane in the flow surface of the top cover and bottom ring using three-dimensional continuous scanning measurement under the same measurement coordinate system; then, using the coordinate points of plane N1, plane N2, P1, Q1, P2, and Q2 in steps S21 and S22, match the three-dimensional measured data of the bottom ring and top cover with the theoretical pre-installed three-dimensional model in step S1 using point, line, and surface matching methods to obtain the coordinate data of the measured scan point cloud in the standard coordinate system of the theoretical pre-installed three-dimensional model;

[0023] S24. Calculate the theoretical measuring points based on the opening values ​​of the top cover and bottom ring in the standard coordinate system from steps S12 and S13. , In the 3D measurement software, the measured coordinates of the nearest measured points for the bottom ring and top cover are obtained by guiding the theoretical coordinate points. , ... ,as well as , ... .

[0024] In this invention, the optimal values ​​for adjusting the opening of the top cover and bottom ring of the water guiding mechanism need to be explained and defined, as follows:

[0025] Preferably, the optimal value for adjusting the opening height of the water guide when the top cover and bottom ring are pre-installed is as follows: First, calculate the corresponding N initial opening values ​​from the existing N measuring points of the water guide mechanism. Then, find an optimal measuring point among the N measuring points and raise or lower it by an optimal value so that the difference between the maximum and minimum values ​​among the original N opening values ​​is minimized. This optimal value is the optimal value for adjusting the opening height of the top cover and bottom ring of the water guide mechanism.

[0026] III. Determining the proportional relationship of the opening adjustment value

[0027] S3. Based on the geometric relationship when adjusting the opening value of the water guiding mechanism, set the adjustment point and adjustment value of its optimal opening value, and determine the proportional relationship between the opening adjustment value of each other point and the optimal adjustment value.

[0028] In step S3, based on the geometric relationship when adjusting the water diversion opening value, assuming that the i-th opening measurement point is the adjustment point of the optimal opening value, the proportional relationship of the change of the opening value of the remaining points is analyzed and determined.

[0029] Preferably, step S3 includes the following steps:

[0030] S31. Let the optimal adjustment point among N open measurement points be the i-th point and the optimal adjustment value be H. i When H iWhen ≥0, the opening value at that point increases by |H i |;When H i When ≤0, the opening value at that point decreases by |H i |;

[0031] Preferably, in step S31, the opening adjustment amount of point i is the largest, and the adjustment amounts of the points adjacent to the left and right sides of point i gradually decrease until the adjustment amounts of the two points that are completely perpendicular to the left and right sides of point i are 0. Then, the adjustment values ​​of the points on the left and right sides are in the opposite direction until the opening adjustment value of the symmetrical point of point i is equal in size and opposite in direction to that of point i.

[0032] S32. Let the radius of the guide vane shaft hole distribution circle be R, then the lifting radius of the i-th point is R, and the lifting radius of its adjacent (i-1)-th point is R. (i-1) for:

[0033]

[0034] Analysis shows that if the opening adjustment value at point i is H i Then the opening adjustment value H of the (i-1)th gear (i-1) With H i The proportional relationship between them is:

[0035]

[0036] By analogy, the opening adjustment value H at the (im)th point can be obtained. (i-m) With H i The proportional relationship between them is:

[0037]

[0038] When N is a multiple of 4, the upper limit of the value of m is N / 4; when N is not a multiple of 4, the upper limit of the value of m is (N+2) / 4.

[0039] In the above steps, the upper limit of the value of m is related to the number of guide vane shafts N. Since the number of guide vanes in the water guiding mechanism is generally an even number, when N is an integer multiple of 4, the upper limit of the value of m is N / 4; when N is not an integer multiple of 4, the upper limit of the value of m is (N+2) / 4.

[0040] In this invention, as can be seen from steps S31 and S32, when adjusting the opening value of the water guiding mechanism, if point i is the maximum adjustment point, the magnitude and direction of the adjustment values ​​at the remaining points are related to the magnitude and direction of the projected radius of the point i in the radial direction. Within the 1 / 4 circumference measuring points near point i, the proportional relationship between the opening adjustment values ​​of successively adjacent measuring points and the adjustment value of point i is as follows:

[0041] When N is a multiple of 4:

[0042]

[0043] Where i = 1, 2...N, m = 1, 2...N / 4;

[0044] When N is not a multiple of 4:

[0045]

[0046] Where i = 1, 2, ..., N, m = 1, 2, ..., (N+2) / 4.

[0047] IV. Exhaustive calculation of the opening value

[0048] S4. Calculate the initial value of the opening of the water guide mechanism using the measured coordinate data from step S2, and use the initial value to obtain the difference of the initial opening value of each symmetrical measuring point group and the initial opening adjustment value; then use the exhaustive method and combine it with the proportional relationship from step S3 to calculate the remaining opening values ​​when each group of symmetrical measuring points is the optimal opening adjustment point and establish the opening value matrix.

[0049] In step S4, the initial value of the water guide mechanism's opening is calculated based on the standardized coordinate system provided by the theoretical assembly model, and the difference in opening values ​​at each symmetrical measuring point is analyzed. Based on the initial opening difference at each symmetrical point, the initial opening adjustment value for that point and its symmetrical points is determined. Then, an exhaustive method is used to calculate the changes in the remaining opening values ​​when each set of symmetrical points is taken as the optimal opening adjustment point.

[0050] Preferably, step S4 includes the following steps:

[0051] S41. In the initial assembly coordinate system of the top cover and bottom ring, let the opening value of the i-th opening measuring point of the bottom ring be K. i Based on the measured opening coordinate data of the top cover and bottom ring in step S24, the initial opening value of the water guiding mechanism is obtained:

[0052]

[0053] S42. Calculate the difference between the opening value of each opening measurement point and its symmetrical point:

[0054]

[0055] In this invention, the adjustable value of any opening measurement point is related to the opening value of its symmetrical point. Therefore, the difference between the opening values ​​of each opening measurement point and its symmetrical point can be calculated using the above formula.

[0056] S43. Calculate the optimal adjustment value of the initial span for a set of symmetrical span measurement points consisting of the i-th point and the (i+N / 2)-th point:

[0057]

[0058] In this invention, the difference obtained from step S42 indicates that for a set of symmetrical opening measurement points consisting of the i-th point and the (i+N / 2)-th point, the optimal adjustment value for the initial opening is as described above. .

[0059] S44. Using the optimal adjustment value from step S43, and combining it with step S3, obtain the corresponding adjustment values ​​for the remaining opening measurement points.

[0060] In this invention, as can be seen from the foregoing analysis, when the water guiding mechanism has a total of N opening measuring points, the total number of pairs of symmetrical opening measuring point groups is N / 2. When the optimal adjustment value of a certain group of opening measuring points is determined by step S43, the corresponding change values ​​of the remaining opening measuring points can be obtained by the analysis and calculation of steps S31 to S32 mentioned above.

[0061] S45. For each set of symmetrical measuring points, exhaustively calculate the changes in the remaining opening values ​​for the optimal opening adjustment value and establish an opening value matrix.

[0062] In this invention, the optimal opening adjustment value of the entire water guiding mechanism refers to finding the adjustment point and adjustment value among all opening measurement points that minimizes the difference between the maximum and minimum opening values. Therefore, by exhaustively calculating the changes in the remaining opening values ​​for each set of symmetrical measurement points in step S44, the optimal opening adjustment value of the entire water guiding mechanism can be found.

[0063] In this invention, to clearly demonstrate the calculation process of the exhaustive method, a symmetrical set of opening measuring points consisting of the first opening measuring point and the (1+N / 2)th opening measuring point is used as an example to calculate and analyze the adjustment of the opening value of the entire water guiding mechanism, as follows:

[0064] Preferably, in the exhaustive method of step S45, for the symmetrical open-section measuring point group consisting of the first open-section measuring point and the (1+N / 2)th open-section measuring point:

[0065] The adjustment value for the first opening measurement point is:

[0066]

[0067] The adjustment value for the second opening measurement point is:

[0068]

[0069] In this invention, as can be seen from step S32, the second opening measuring point is an adjacent measuring point of the first opening measuring point, and its opening adjustment is proportional to the adjustment value of the first opening measuring point. Therefore, the adjustment value of the second opening measuring point is as shown in the above formula.

[0070] Similarly, when 1≤m≤N / 4, the opening value of the m-th opening measuring point is:

[0071]

[0072] When the number of the opening measurement point exceeds N / 4, as can be seen from step S31, the direction of the adjustment value of that opening measurement point will change, but the magnitude of the adjustment value will be the same as the adjustment magnitude of the corresponding previous measurement point. Therefore:

[0073] When m = N / 4 + 1:

[0074]

[0075] When N / 4+1<m≤N / 2:

[0076]

[0077] When m = N / 2 + 1:

[0078]

[0079] When N / 2+1<m≤3N / 4:

[0080]

[0081] When m = 3N / 4 + 1:

[0082]

[0083] When 3N / 4 < m ≤ N:

[0084]

[0085] Therefore, when the number of guide vane shaft holes N is an integer multiple of 4, the adjustment value of the opening measuring point is:

[0086]

[0087] When the number of guide vane shaft holes N is not an integer multiple of 4, the adjustment value of the opening measuring point is:

[0088]

[0089] From the adjustment values ​​of each opening measurement point obtained above, the adjusted opening value for all opening measurement points is obtained as follows:

[0090] .

[0091] In this invention, the above method is merely an example illustrating the change in the opening value of the entire water guiding mechanism when the symmetrical opening point consisting of the first opening measuring point and the (1+N / 2)th opening measuring point is taken as the optimal opening adjustment value in the exhaustive calculation. For the remaining N / 2-1 symmetrical opening measuring point groups, the remaining opening adjustment values ​​can be obtained by referring to the change pattern in step S31 and the above calculation method.

[0092] Preferably, in step S45, the adjusted opening value in the plurality of symmetrically spaced measuring point groups is:

[0093]

[0094] The matrix composed of the adjusted opening values ​​of several symmetrically set opening measurement points is as follows:

[0095] .

[0096] In this invention, all values ​​for the opening adjustment of the water guiding mechanism are calculated exhaustively using the above formula and then arranged into the matrix above. The optimal opening adjustment value of the entire water guiding mechanism is obtained by comparing and calculating the adjusted opening value represented by each row.

[0097] V. Determining the Optimal Value and Location

[0098] S5. Using the opening value matrix from step S4, determine the optimal adjustment value, position, and optimal opening value of the water guiding mechanism.

[0099] In step S5, based on the aforementioned analysis, the optimal value and position for adjusting the opening of the water guiding mechanism are determined.

[0100] Preferably, step S5 includes the following steps:

[0101] S51. In all N / 2 pairs of opening adjustment groups calculated exhaustively in step S4, calculate the difference between the maximum and minimum values ​​of all opening values ​​after adjustment for each group. :

[0102]

[0103] S52, for all By comparing the values, the minimum value is identified and its corresponding number is set as Z. This represents the optimal value after the entire water guiding mechanism has been adjusted. for:

[0104] .

[0105] In the above steps, for all Comparison, among which The minimum value represents the position of the entire water guiding mechanism's opening adjustment, which is denoted as Z. The optimal value after the entire water guiding mechanism's opening adjustment is then determined. This can be expressed using the above formula. In the formula... The above are calculated from the steps mentioned above.

[0106] The beneficial effects of this invention are:

[0107] The optimal opening value determination method provided by this invention is used to analyze and determine the optimal value of the opening value of the guide vane mechanism after adjustment during digital pre-assembly of the guide vane mechanism of a water pump turbine, and to determine whether the opening value of the guide vane mechanism after assembly meets the acceptance requirements. Digital pre-assembly of the guide vane mechanism instead of physical pre-assembly not only satisfies the same requirements for judging the assembly quality and accepting key data, but also significantly reduces energy consumption and shortens the assembly cycle. Furthermore, the measured data and models of each component obtained through reverse measurement can be used for comprehensive quality judgment of component processing and the realization of digital twin products.

[0108] Currently, digital pre-assembly technology is still a cutting-edge technology in the field of water turbine manufacturing, and has not yet been fully applied and promoted. This invention analyzes and standardizes the calculation method for the optimal opening value of the guide vane during the key acceptance test of the digital pre-assembly of the guide vane mechanism of a water pump turbine. This provides an important technical foundation and key support for judging the assembly quality of the guide vane mechanism of a water pump turbine through digital pre-assembly. Attached Figure Description

[0109] Figure 1 This is a schematic diagram of the bottom ring theoretical model of the present invention;

[0110] Figure 2 This is a schematic diagram of the theoretical pre-assembly model of the top cover and bottom ring of the present invention;

[0111] Figure 3 This is a schematic diagram of the three-dimensional measurement data of the bottom ring of the present invention;

[0112] Figure 4 This is a schematic diagram of the three-dimensional measurement data of the top cover of the present invention;

[0113] Figure 5 This is a schematic diagram illustrating the matching of the bottom ring measurement data with the theoretical model of the present invention;

[0114] Figure 6 This is a schematic diagram showing the matching of the top cover measurement data and the theoretical model of the present invention;

[0115] Figure 7 This is a schematic diagram of the opening adjustment analysis of the present invention;

[0116] Figure 8 The proportional relationship between adjacent measuring points is adjusted according to the present invention.

[0117] Figure label:

[0118] Figure 1 In the middle: 1. N# guide vane shaft hole; 2. N# theoretical opening measuring point coordinates (P TN ); 3. Guide vane shaft hole #1; 4. Coordinates of theoretical opening measuring point #1 (P) T1 ); 5. Guide vane shaft hole #2; 6. Coordinates of theoretical opening measuring point #2 (P) T2 ); 7. Center distribution circle of guide vane shaft hole (L2); 8. Vertical bisector of the center of guide vane shaft hole #1 and #2 (L1);

[0119] Figure 2 Middle: 9. Bottom ring; 10. Top cover;

[0120] Figure 3 In the middle: 11. Bottom ring scanning measurement point cloud; 12. Center of bottom ring #1 shaft hole; 13. N1 plane; 14. Center of bottom ring leak-proof ring;

[0121] Figure 4 In the middle: 15. Top cover scanning measurement point cloud; 16. Center of top cover #1 shaft hole; 17. N2 plane; 18. Center of top cover leak-proof ring;

[0122] Figure 7 In the middle: 19. Opening the gap at point i; 20. Opening the gap at the point symmetrical to point i;

[0123] Figure 8 In the middle: 21, the i-th open-end measurement point; 22, the (i-1)-th open-end measurement point. Detailed Implementation

[0124] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention.

[0125] Example 1

[0126] A method for determining the optimal opening value of a pump-turbine guide vane mechanism via digital pre-installation includes the following steps:

[0127] S1. Based on the design dimensions of the top cover and bottom ring, as well as the assembly constraints and design opening values ​​of the water guiding mechanism, establish a theoretical pre-installation three-dimensional model, and obtain the coordinate data of the theoretical measuring points of the top cover and bottom ring opening values ​​in the theoretical pre-installation three-dimensional model;

[0128] S2. In the physical model after production and processing, the flow surfaces of the top cover and bottom ring are measured in three dimensions to obtain the original measurement data. The measurement data is preprocessed and matched with the theoretical pre-installed three-dimensional model in step S1. Then, based on the coordinate data of the theoretical measurement points in step S1, the basic data of the measured coordinates of the bottom ring and top cover are obtained.

[0129] S3. Based on the geometric relationship when adjusting the opening value of the water guiding mechanism, set the adjustment point and adjustment value of its optimal opening value, and determine the proportional relationship between the opening adjustment value of each other point and the optimal adjustment value.

[0130] S4. Calculate the initial value of the opening of the water guide mechanism using the measured coordinate data from step S2, and use the initial value to obtain the difference of the initial opening value of each symmetrical measuring point group and the initial opening adjustment value; then use the exhaustive method and combine it with the proportional relationship from step S3 to calculate the remaining opening values ​​when each group of symmetrical measuring points is the optimal opening adjustment point and establish the opening value matrix.

[0131] S5. Using the opening value matrix from step S4, determine the optimal adjustment value, position, and optimal opening value of the water guiding mechanism.

[0132] Example 2

[0133] This embodiment further elaborates on step S1 based on embodiment 1. In step S1, a standardized theoretical pre-assembled three-dimensional model of the top cover and bottom ring is established in the Cartesian coordinate system according to the design dimensions of the top cover and bottom ring, the assembly constraints of the water guiding mechanism, and the design opening value. The coordinate data of the theoretical measurement points of the opening value of the top cover and bottom ring are obtained in turn.

[0134] Step S1 includes the following steps:

[0135] S11. Establish three-dimensional models of the top cover and bottom ring respectively based on the design values ​​of the top cover and bottom ring; in the three-dimensional model of the bottom ring, establish a Cartesian coordinate system by setting the center of the leak-stop ring as the origin, the line connecting the center of the leak-stop ring and the center of the #1 shaft hole as the +X axis, and setting the upward-facing sealing opening plane as the +Z axis. Figure 1 As shown; and based on the design opening value and assembly constraints of the water guiding mechanism, the top cover and bottom ring are assembled to obtain a theoretical pre-assembled three-dimensional model for calculating the opening of the water guiding mechanism, as shown. Figure 2 As shown;

[0136] S12. Assume the water guiding mechanism has N guide vanes. Using the bottom ring sealing and opening plane as the reference plane, let L1 be the perpendicular bisector of the line connecting the centers of guide vane #1 and guide vane #2, and L2 be the center distribution circle of the guide vanes. The intersection of L1 and L2 is the theoretical measuring point #1 for calculating the bottom ring opening value, and its coordinates are... Then, using the origin as the reference point, the remaining theoretical measurement points for the bottom ring are obtained sequentially using a circular array. , ... ,like Figure 1 As shown;

[0137] S13. Taking the top cover sealing and opening plane as the reference plane, let L3 be the perpendicular bisector of the line connecting the centers of guide vane shaft holes #1 and #2, and L4 be the guide vane center distribution circle. The intersection of L3 and L4 is the theoretical measuring point #1 for calculating the top cover opening value, and its coordinates are: Then, using the origin of the coordinate system as the reference point, the remaining theoretical measurement points for calculating the opening of the top cover are obtained sequentially using a circular array. , ... .

[0138] Example 3

[0139] This embodiment further elaborates on step S2 based on embodiment 2. In step S2, a comprehensive three-dimensional measurement of the flow surfaces of the top cover and bottom ring is performed to obtain the original measurement data. The measurement data is then processed to obtain the basic data that can be used for the next step of optimization calculation.

[0140] Step S2 includes the following steps:

[0141] S21, such as Figure 3 As shown, in the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the bottom ring flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N1 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N1 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected circle of the leak-stop ring. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ;

[0142] In the above steps, the number of measuring points for the sealing opening plane, the leak-proof ring cylindrical surface, and the No. 1 guide vane shaft hole is ≥3.

[0143] S22, such as Figure 4 As shown, in the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the top cover flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N2 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N2 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected leak-stop ring circle. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ;

[0144] In the above steps, the number of measuring points for the sealing opening plane, the leak-proof ring cylindrical surface, and the No. 1 guide vane shaft hole is ≥3.

[0145] S23. Based on steps S21 and S22, obtain point cloud data of the sealing opening plane in the flow surface of the top cover and bottom ring using a three-dimensional continuous scanning measurement method under the same measurement coordinate system; then, using the coordinate points of plane N1, plane N2, P1, Q1, P2, and Q2 from steps S21 and S22, match the three-dimensional measured data of the bottom ring and top cover with the theoretical pre-installed three-dimensional model from step S1 using point, line, and surface matching methods to obtain the coordinate data of the measured scan point cloud in the standard coordinate system of the theoretical pre-installed three-dimensional model, such as... Figure 5 , 6 As shown;

[0146] S24. Calculate the theoretical measuring points based on the opening values ​​of the top cover and bottom ring in the standard coordinate system from steps S12 and S13. , In the 3D measurement software, the measured coordinates of the nearest measured points for the bottom ring and top cover are obtained by guiding the theoretical coordinate points. , ... ,as well as , ... .

[0147] In this invention, the optimal values ​​for adjusting the opening of the top cover and bottom ring of the water guiding mechanism need to be explained and defined. Specifically, the following steps are taken: First, calculate the corresponding N initial opening values ​​from the existing N measuring points of the water guiding mechanism. Then, find an optimal measuring point among the N measuring points and raise or lower it by an optimal value so that the difference between the maximum and minimum values ​​among the original N opening values ​​is minimized. This optimal value is the optimal value for adjusting the opening height of the top cover and bottom ring of the water guiding mechanism.

[0148] Example 4

[0149] This embodiment further elaborates on step S3 based on embodiment 3. In step S3, based on the geometric relationship when adjusting the water diversion opening value, it is assumed that the i-th opening measurement point is the adjustment point of the optimal opening value, and the proportional relationship of the change of the opening value of the remaining points is analyzed and determined.

[0150] Step S3 includes the following steps:

[0151] S31. Let the optimal adjustment point among N open measurement points be the i-th point and the optimal adjustment value be H. i When H i When ≥0, the opening value at that point increases |H i |;When H i When ≤0, the opening value at that point decreases by |H i |;

[0152] In step S31, the opening adjustment amount at point i is the largest. The adjustment amounts of the points adjacent to point i on both sides gradually decrease until the adjustment amounts of the two points that are completely perpendicular to point i on both sides are 0. Then, the adjustment values ​​of the points on both sides forward are in the opposite direction until the opening adjustment value of the point symmetrical to point i is equal in magnitude and opposite in direction to that of point i. Figure 7 As shown.

[0153] S32, such as Figure 8 As shown, let the radius of the guide vane shaft hole distribution circle be R, then the lifting radius of the i-th point is R, and the lifting radius of its adjacent (i-1)-th point is R. (i-1) for:

[0154]

[0155] Analysis shows that if the opening adjustment value at point i is H i Then the opening adjustment value H of the (i-1)th gear. (i-1) With H i The proportional relationship between them is:

[0156]

[0157] By analogy, the opening adjustment value H at the (im)th point can be obtained. (i-m) With H i The proportional relationship between them is:

[0158]

[0159] When N is a multiple of 4, the upper limit of the value of m is N / 4; when N is not a multiple of 4, the upper limit of the value of m is (N+2) / 4.

[0160] In the above steps, the upper limit of the value of m is related to the number of guide vane shafts N. Since the number of guide vanes in the water guiding mechanism is generally an even number, when N is an integer multiple of 4, the upper limit of the value of m is N / 4; when N is not an integer multiple of 4, the upper limit of the value of m is (N+2) / 4.

[0161] In this invention, as can be seen from steps S31 and S32, when adjusting the opening value of the water guiding mechanism, if point i is the maximum adjustment point, the magnitude and direction of the adjustment values ​​at the remaining points are related to the magnitude and direction of the projected radius of the point i in the radial direction. Within the 1 / 4 circumference measuring points near point i, the proportional relationship between the opening adjustment values ​​of successively adjacent measuring points and the adjustment value of point i is as follows:

[0162] When N is a multiple of 4:

[0163]

[0164] Where i = 1, 2...N, m = 1, 2...N / 4;

[0165] When N is not a multiple of 4:

[0166]

[0167] Where i = 1, 2, ..., N, m = 1, 2, ..., (N+2) / 4.

[0168] Example 5

[0169] This embodiment further elaborates on step S4 based on embodiment 4. In step S4, the initial value of the water guide mechanism opening is calculated according to the standardized coordinate system provided by the theoretical assembly model, and the difference in opening difference between each symmetrical measuring point is analyzed. The initial opening adjustment value of the point and its symmetrical points is determined based on the initial opening difference of each symmetrical point. Then, the exhaustive method is used to calculate the change of the remaining opening values ​​when each group of symmetrical points is taken as the optimal opening adjustment point.

[0170] Step S4 includes the following steps:

[0171] S41. In the initial assembly coordinate system of the top cover and bottom ring, let the opening value of the i-th opening measuring point of the bottom ring be K. i Based on the measured opening coordinate data of the top cover and bottom ring in step S24, the initial opening value of the water guiding mechanism is obtained:

[0172]

[0173] S42. Calculate the difference between the opening value of each opening measurement point and its symmetrical point:

[0174]

[0175] In this invention, the adjustable value of any opening measurement point is related to the opening value of its symmetrical point. Therefore, the difference between the opening values ​​of each opening measurement point and its symmetrical point can be calculated using the above formula.

[0176] S43. Calculate the optimal adjustment value of the initial span for a set of symmetrical span measurement points consisting of the i-th point and the (i+N / 2)-th point:

[0177]

[0178] In this invention, the difference obtained from step S42 indicates that for a set of symmetrical opening measurement points consisting of the i-th point and the (i+N / 2)-th point, the optimal adjustment value for the initial opening is as described above. .

[0179] S44. Using the optimal adjustment value from step S43, and combining it with step S3, obtain the corresponding adjustment values ​​for the remaining opening measurement points.

[0180] In this invention, as can be seen from the foregoing analysis, when the water guiding mechanism has a total of N opening measuring points, the total number of pairs of symmetrical opening measuring point groups is N / 2. When the optimal adjustment value of a certain group of opening measuring points is determined by step S43, the corresponding change values ​​of the remaining opening measuring points can be obtained by the analysis and calculation of steps S31 to S32 mentioned above.

[0181] S45. For each set of symmetrical measuring points, exhaustively calculate the changes in the remaining opening values ​​for the optimal opening adjustment value and establish an opening value matrix.

[0182] In this invention, as shown in step S3, the optimal opening adjustment value of the entire water guiding mechanism refers to finding the adjustment point and adjustment value among all opening measurement points that minimizes the difference between the maximum and minimum opening values. Therefore, if the optimal opening adjustment value of each group of symmetrical measurement points in step S44 is exhaustively calculated for the changes in the remaining opening values, the optimal opening adjustment value of the entire water guiding mechanism can be found.

[0183] In this invention, to clearly demonstrate the calculation process of the exhaustive method, a symmetrical set of opening measuring points consisting of the first opening measuring point and the (1+N / 2)th opening measuring point is used as an example to calculate and analyze the adjustment of the opening value of the entire water guiding mechanism, as follows:

[0184] In the exhaustive method of step S45, for the symmetrical set of open-range measuring points consisting of the first open-range measuring point and the (1+N / 2)th open-range measuring point:

[0185] The adjustment value for the first opening measurement point is:

[0186]

[0187] The adjustment value for the second opening measurement point is:

[0188]

[0189] In this invention, as can be seen from step S32, the second opening measuring point is an adjacent measuring point of the first opening measuring point, and its opening adjustment is proportional to the adjustment value of the first opening measuring point. Therefore, the adjustment value of the second opening measuring point is as shown in the above formula.

[0190] Similarly, when 1≤m≤N / 4, the opening value of the m-th opening measuring point is:

[0191]

[0192] When the number of the opening measurement point exceeds N / 4, as can be seen from step S31, the direction of the adjustment value of that opening measurement point will change, but the magnitude of the adjustment value will be the same as the adjustment magnitude of the corresponding previous measurement point. Therefore:

[0193] When m = N / 4 + 1:

[0194]

[0195] When N / 4+1<m≤N / 2:

[0196]

[0197] When m = N / 2 + 1:

[0198]

[0199] When N / 2+1<m≤3N / 4:

[0200]

[0201] When m = 3N / 4 + 1:

[0202]

[0203] When 3N / 4 < m ≤ N:

[0204]

[0205] Therefore, when the number of guide vane shaft holes N is an integer multiple of 4, the adjustment value of the opening measuring point is:

[0206]

[0207] When the number of guide vane shaft holes N is not an integer multiple of 4, the adjustment value of the opening measuring point is:

[0208]

[0209] From the adjustment values ​​of each opening measurement point obtained above, the adjusted opening value for all opening measurement points is obtained as follows:

[0210] .

[0211] In this invention, the above method is merely an example illustrating the change in the opening value of the entire water guiding mechanism when the symmetrical opening point consisting of the first opening measuring point and the (1+N / 2)th opening measuring point is taken as the optimal opening adjustment value in the exhaustive calculation. For the remaining N / 2-1 symmetrical opening measuring point groups, the remaining opening adjustment values ​​can be obtained by referring to the change pattern in step S31 and the above calculation method.

[0212] In step S45, the adjusted opening value in the group of symmetrically spaced measuring points is:

[0213]

[0214] The matrix composed of the adjusted opening values ​​of several symmetrically set opening measurement points is as follows:

[0215] .

[0216] In this invention, all values ​​for the opening adjustment of the water guiding mechanism are calculated exhaustively using the above formula and then arranged into the matrix above. The optimal opening adjustment value of the entire water guiding mechanism is obtained by comparing and calculating the adjusted opening value represented by each row.

[0217] Example 6

[0218] This embodiment further elaborates on step S5 based on embodiment 5. In step S5, the optimal value and position of the opening adjustment of the water guiding mechanism are determined according to the aforementioned analysis.

[0219] The S5 step includes the following steps:

[0220] S51. In all N / 2 pairs of opening adjustment groups calculated exhaustively in step S4, calculate the difference between the maximum and minimum values ​​of all opening values ​​after adjustment for each group. :

[0221]

[0222] S52, for all By comparing the values, the minimum value is identified and designated as Z. This represents the optimal value after the entire water guiding mechanism has been adjusted. for:

[0223] .

[0224] In the above steps, for all Comparison, among which The minimum value represents the position of the entire water guiding mechanism's opening adjustment, which is denoted as Z. The optimal value after the entire water guiding mechanism's opening adjustment is then determined. This can be expressed using the above formula. In the formula... The above are calculated from the steps mentioned above.

[0225] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalents or substitutions are all included within the scope defined by the claims of the present invention.

Claims

1. A method for determining the optimal opening value of a water pump turbine guide vane mechanism via digital pre-installation, characterized in that, Includes the following steps: S1. Based on the design dimensions of the top cover and bottom ring, as well as the assembly constraints and design opening values ​​of the water guiding mechanism, establish a theoretical pre-installation three-dimensional model, and obtain the coordinate data of the theoretical measuring points of the top cover and bottom ring opening values ​​in the theoretical pre-installation three-dimensional model; S2. In the physical model after production and processing, the flow surfaces of the top cover and bottom ring are measured in three dimensions to obtain the original measurement data. The measurement data is preprocessed and matched with the theoretical pre-installed three-dimensional model in step S1. Then, based on the coordinate data of the theoretical measurement points in step S1, the basic data of the measured coordinates of the bottom ring and top cover are obtained. S3. Based on the geometric relationship when adjusting the opening value of the water guiding mechanism, set the adjustment point and adjustment value of its optimal opening value, and determine the proportional relationship between the opening adjustment value of each other point and the optimal adjustment value. Step S3 includes the following steps: S31. Let the optimal adjustment point among N open measurement points be the i-th point and the optimal adjustment value be H. i When H i When ≥0, the opening value at that point increases |H i |;When H i When ≤0, the opening value at that point decreases by |H i |; In step S31, the opening adjustment amount of point i is the largest, and the adjustment amount of the points adjacent to the left and right sides of point i gradually decreases until the adjustment amount of the two points that are completely perpendicular to the left and right sides of point i is 0. Then, the adjustment amount of the points on the left and right sides is in the opposite direction until the opening adjustment value of the symmetrical point of point i is equal in size and opposite in direction to that of point i. S32. Determine the opening adjustment value H for the (im)th point. (i-m) With H i The proportional relationship between them is: Wherein, when N is an integer multiple of 4, the upper limit of the value of m is N / 4; when N is not an integer multiple of 4, the upper limit of the value of m is (N+2) / 4; S4. Calculate the initial value of the opening of the water guide mechanism using the measured coordinate data from step S2, and use the initial value to obtain the difference of the initial opening value of each symmetrical measuring point group and the initial opening adjustment value; then use the exhaustive method and combine it with the proportional relationship from step S3 to calculate the remaining opening values ​​when each group of symmetrical measuring points is the optimal opening adjustment point and establish the opening value matrix. S5. Using the opening value matrix from step S4, determine the optimal adjustment value, position, and optimal opening value of the water guiding mechanism.

2. The method for determining the optimal opening value as described in claim 1, characterized in that, Step S1 includes the following steps: S11. Establish three-dimensional models of the top cover and bottom ring respectively based on the design values ​​of the top cover and bottom ring. In the three-dimensional model of the bottom ring, set the center of the leak-stop ring as the origin of the coordinate system, set the line connecting the center of the leak-stop ring and the center of the #1 shaft hole as the +X axis, and set the upward-facing sealing opening plane as the +Z axis to establish a Cartesian coordinate system. Based on the design opening value of the water guiding mechanism and the assembly constraint relationship, assemble the top cover and bottom ring to obtain the theoretical pre-assembled three-dimensional model of the water guiding mechanism opening calculation. S12. Assume the water guiding mechanism has N guide vanes. Using the bottom ring sealing and opening plane as the reference plane, let L1 be the perpendicular bisector of the line connecting the centers of guide vane #1 and guide vane #2, and L2 be the center distribution circle of the guide vanes. The intersection of L1 and L2 is the theoretical measuring point #1 for calculating the bottom ring opening value, and its coordinates are... Then, using the origin as the reference point, the remaining theoretical measurement points for the bottom ring are obtained sequentially using a circular array. , ... ; S13. Taking the top cover sealing and opening plane as the reference plane, let L3 be the perpendicular bisector of the line connecting the centers of guide vane shaft holes #1 and #2, and L4 be the guide vane center distribution circle. The intersection of L3 and L4 is the theoretical measuring point #1 for calculating the top cover opening value, and its coordinates are: Then, using the origin of the coordinate system as the reference point, the remaining theoretical measurement points for calculating the opening of the top cover are obtained sequentially using a circular array. , ... .

3. The method for determining the optimal opening value as described in claim 2, characterized in that, Step S2 includes the following steps: S21. In the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the bottom ring flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N1 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N1 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected circle of the leak-stop ring. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ; S22. In the completed physical model, the measured coordinate data of the sealing opening plane, the leak-stop ring cylindrical surface, and the No. 1 guide vane shaft hole on the top cover flow surface are obtained through three-dimensional contact measurement. Then, the measured coordinates of the sealing opening plane are fitted into plane N2 using the least squares method. The measured coordinates of the leak-stop ring cylindrical surface and the No. 1 guide vane shaft hole are first projected onto plane N2 and then fitted into a circle using the least squares method to obtain the coordinates of the center of the projected leak-stop ring circle. Coordinates of the center of the projected circle of the #1 guide vane shaft hole ; S23. Based on steps S21 and S22, obtain point cloud data of the sealing opening plane in the flow surface of the top cover and bottom ring using three-dimensional continuous scanning measurement under the same measurement coordinate system; then, using the coordinate points of plane N1, plane N2, P1, Q1, P2, and Q2 in steps S21 and S22, match the three-dimensional measured data of the bottom ring and top cover with the theoretical pre-installed three-dimensional model in step S1 using point, line, and surface matching methods to obtain the coordinate data of the measured scan point cloud in the standard coordinate system of the theoretical pre-installed three-dimensional model; S24. Calculate the theoretical measuring points based on the opening values ​​of the top cover and bottom ring in the standard coordinate system from steps S12 and S13. , In the 3D measurement software, the measured coordinates of the nearest measured points of the bottom ring and top cover are obtained by guiding the theoretical coordinate points. , ... ,as well as , ... .

4. The method for determining the optimal opening value as described in claim 3, characterized in that, Step S4 includes the following steps: S41. In the initial assembly coordinate system of the top cover and bottom ring, let the opening value of the i-th opening measuring point of the bottom ring be K. i Based on the measured opening coordinate data of the top cover and bottom ring in step S24, the initial opening value of the water guiding mechanism is obtained: S42. Calculate the difference between the opening value of each opening measurement point and its symmetrical point: S43. Calculate the optimal adjustment value of the initial span for a set of symmetrical span measurement points consisting of the i-th point and the (i+N / 2)-th point: S44. Using the optimal adjustment value from step S43, and combining it with step S3, obtain the corresponding adjustment values ​​for the remaining opening measurement points. S45. For each set of symmetrical measuring points, exhaustively calculate the changes in the remaining opening values ​​for the optimal opening adjustment value and establish an opening value matrix.

5. The method for determining the optimal opening value as described in claim 4, characterized in that, In the exhaustive method of step S45, for the symmetrical set of open-range measuring points consisting of the first open-range measuring point and the (1+N / 2)th open-range measuring point: When the number of guide vane shaft holes N is an integer multiple of 4, the adjustment value of the opening measuring point is: When the number of guide vane shaft holes N is not an integer multiple of 4, the adjustment value of the opening measuring point is: From the adjustment values ​​of each opening measurement point obtained above, the adjusted opening value for all opening measurement points is obtained as follows: 。 6. The method for determining the optimal opening value as described in claim 5, characterized in that, In step S45, the adjusted opening value in the group of symmetrically opened measuring points is: The matrix composed of the adjusted opening values ​​of several symmetrically set opening measurement points is as follows: 。 7. The method for determining the optimal opening value as described in claim 4, characterized in that, Step S5 includes the following steps: S51. In all N / 2 pairs of opening adjustment groups calculated exhaustively in step S4, calculate the difference between the maximum and minimum values ​​of all opening values ​​after adjustment for each group. : S52, for all By comparing the values, the minimum value is identified and designated as Z. This represents the optimal value after the entire water guiding mechanism has been adjusted. for: 。 8. The method for determining the optimal opening value as described in claim 1, characterized in that, The optimal value for adjusting the opening height of the water guide mechanism during pre-installation of the top cover and bottom ring is as follows: First, calculate the corresponding N initial opening values ​​from the existing N measuring points of the water guide mechanism. Then, find an optimal measuring point among the N measuring points and raise or lower it by an optimal value to minimize the difference between the maximum and minimum values ​​among the original N opening values. This optimal value is the optimal value for adjusting the opening height of the top cover and bottom ring of the water guide mechanism.

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