Method for improving strength of water turbine blade in water conservancy project

Abstract

The invention provides a strength improving method for a water turbine blade in a water conservancy project, and relates to the technical field of water turbine blades, the strength improving method comprises the following steps: S1, recording the shape and the section shape of the blade; s2, establishing a storm gutter channel model and performing hydrodynamic performance test; s3, through blade tip optimization, the interaction between the pressure surface and the suction surface at the blade tip is changed; s4, analyzing the influence of blade tip optimization on the hydrodynamic performance of the water turbine; s5, establishing a fluid-structure interaction control equation of the flexible blade in the fluid; by means of the design, the hydrodynamic performance of the blade can be effectively improved, local corrosion can be effectively reduced, then the risk of blade breakage is reduced, stress is effectively dispersed, local stress concentration is reduced, the risk of fatigue damage caused by stress concentration of the blade is reduced, and by avoiding the resonant frequency and optimizing the transition radius of the arc of the welding seam, the service life of the blade is prolonged. The vibration strength of the blade in the working process is reduced, and the stability of the blade in the operation process is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of water turbine blades, and in particular to a method for improving the strength of water turbine blades in water conservancy projects. Background Art

[0002] Turbine blades are a key component of the turbine in a hydroelectric power generation system. They are a series of precisely designed blades installed on the runner of the turbine. When water flows through, the blades convert the kinetic energy of the water into mechanical energy, driving the runner to rotate, and then driving the generator to generate electricity.

[0003] However, in actual water conservancy projects, due to the complexity and variability of water flow conditions, traditional turbine blades are very prone to local corrosion, such as pitting, erosion corrosion and corrosion fatigue, under the interaction of water flow, strong scouring of sediment and complex underwater electrochemical environment. This corrosion will cause the performance of the blade material to deteriorate, and the downward force of the water flow will increase the design stress of the blade, causing stress concentration and even perforation, which will lead to the fracture of the turbine blade. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and provide a method for improving the strength of turbine blades in water conservancy projects.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: A method for improving the strength of turbine blades in a water conservancy project, comprising the following steps:

[0006] S1. Record the shape and cross-sectional shape of the blade;

[0007] S2. Establish wind-wave-current flume model and hydrodynamic performance test;

[0008] S3, by optimizing the blade tip, changing the interaction between the pressure surface and the suction surface at the blade tip;

[0009] S4. Analyze the influence of blade tip optimization on the hydrodynamic performance of turbines;

[0010] S5. Establish the fluid-solid coupling control equation of the flexible blade in the fluid;

[0011] S6, solving blade deformation and establishing instantaneous physical model;

[0012] S7. Blade strength and stiffness test.

[0013] As a preferred implementation, in step S2, the specific steps are: constructing an autonomous scene by selecting different geology, terrain and obstacles to explore the interaction between waves and terrain;

[0014] In step S2, the specific steps are: selecting appropriate experimental instruments, such as a wave measuring rod and a pitot tube, and installing them at corresponding positions of the water tank, and performing correct installation and calibration.

[0015] As a preferred implementation, in step S2, the specific steps are: determining a calibration coefficient, calibrating the relationship between load and reading, including calibration of a torque and speed measuring instrument and current and voltage signals;

[0016] In step S2, the specific steps are: creating a new test project in the data acquisition and analysis processing system software, performing balancing, clearing and recording;

[0017] In step S2, the specific steps are: start the circulating water tank and set the water flow rate to the experimental flow rate;

[0018] In step S2, the specific steps are: measuring the torque, speed, force values ​​of the front and rear strain gauges, and the output of current and voltage of the main shaft of the turbine under various working conditions;

[0019] In step S2, the specific steps are: closing the circulating water tank and removing the impeller; then opening the circulating water tank to the experimental speed and reading the stress value of the strain gauge.

[0020] As a preferred implementation, in step S3, the specific steps are: using blade element momentum theory to obtain the distribution of blade torsion angle and chord, and establishing a parameterized model of the original rotor based on this;

[0021] In step S3, the specific steps are: applying the blade blade technology to the design of tidal energy turbine blades;

[0022] In the step S3, the specific steps are: applying the winglet technology to the design of tidal energy turbine blades;

[0023] In the step S3, the specific steps are: conducting a hydrodynamic performance study on the blade improvement scheme, including comparative analysis of blade surface pressure data, velocity flow field data, and energy capture coefficient Cp data.

[0024] As a preferred implementation, in step S4, the specific steps are: establishing a water turbine tank model test system and a hydrodynamic performance test platform, and performing a large number of tests such as variable pitch angle, variable blade number, and variable flow rate on different types of blades to obtain parameters such as speed, power, and torque of the turbine under different working conditions;

[0025] In step S4, the specific steps are: studying the influence of blade tails of different shapes and thicknesses on the performance of the unit, especially the performance under reverse working conditions.

[0026] As a preferred implementation, in step S5, the specific steps are: establishing a three-dimensional finite element analysis model of the Francis turbine integral runner blade and a single blade;

[0027] In step S5, the specific steps are: using the fluid-solid coupling function in the finite element software to perform modal analysis on the overall runner blade and the single blade, obtain the self-vibration characteristics of the runner blade and the single blade in the air and in the static fluid, and perform comparative analysis.

[0028] As a preferred implementation, in step S6, the specific steps are: on a preset fluid-solid coupling interface, the aerodynamic load / temperature field is transmitted to the structural field, and the geometric deformation / solid temperature is transmitted to the flow field, and the converged coupled multi-physics field results are obtained by iterative solution;

[0029] In step S6, the specific steps are: performing time domain iterative solutions for the flow field and the structural field according to a preset total time length and time step, and obtaining a bidirectional fluid-solid coupling solution result that changes in the time domain after final convergence;

[0030] In the step S6, the specific steps are: on a preset fluid-solid coupling interface, aerodynamic loads and geometric deformations are iteratively solved to obtain converged coupled multi-physics field results;

[0031] In step S6, the specific steps are: according to the deformation result of the blade, an instantaneous physical model is established to simulate the dynamic behavior of the blade in the fluid, including the flapping, shimmying and torsional deformation of the blade.

[0032] As a preferred implementation, in step S7, the specific steps are: finding resonance points that may appear on the blade, and designing the geometric parameters of the blade to avoid these resonance points;

[0033] In step S7, the specific steps are: according to the stress distribution of the blade, appropriately increase the thickness of the blade, especially in the high stress area, so as to improve the bearing capacity of the blade and reduce stress concentration;

[0034] In step S7, the specific steps are: optimizing the arc transition radius of the weld at the connection between the blade and the upper crown and the lower ring to reduce stress concentration and improve stress distribution;

[0035] In step S7, the specific steps are: comprehensively measuring the vibration characteristics of the blades of the newly installed unit, including the identification of the frequency dispersion rate and the resonance safety rate, to ensure the optimal shape of the blades during operation.

[0036] Compared with the prior art, the advantages and positive effects of the present invention are

[0037] By establishing a wind-wave flow flume model and conducting hydrodynamic performance tests, the working state of the turbine in the actual water flow environment is simulated. In the experiment, wave measuring rods, Pitot tubes and other equipment are used to monitor the changes in water surface height and fluid velocity distribution, and the torque, speed and stress data of the turbine main shaft are measured under different working conditions to optimize the design of the turbine blades. This design can simulate the interaction between water flow and blades in a real environment by selecting different bottom materials, terrains and obstacles, monitor the torque, speed and stress values ​​of the turbine, accurately understand the effects of water flow, sediment, corrosion and other factors on the blades, and on this basis optimize the blade design to reduce stress concentration and corrosion risks.

[0038] The use of winglets and wingtip winglet technology at the blade tip can significantly improve the hydrodynamic performance. These technologies improve blade efficiency by improving airflow distribution and reducing vortex resistance. Combined with blade element momentum theory, the torsion angle and chord length of the blade can be accurately calculated to ensure reasonable design and stable performance. Through hydrodynamic performance tests and experiments, the operating performance of the improved blades can be comprehensively evaluated. In this way, by applying winglets and wingtip winglet technology, as well as conducting hydrodynamic performance tests and fluid-solid coupling analysis, the hydrodynamic performance of the blades can be effectively improved, local corrosion can be reduced, and the design stress of the blades can be reduced, thereby reducing the risk of blade breakage.

[0039] Through the physical model of fluid-solid coupling, the dynamic response of turbine blades in a complex fluid environment is simulated, and then the aerodynamic load, temperature field and geometric deformation of the blades are transmitted to the structural field, and the interaction between the fluid and the structure is iteratively solved. The deformation and stress state of the blades under different working conditions can be tracked in real time. This multi-physical field coupling simulation reflects the dynamic behavior of the blades in actual operation, such as flapping, swinging, torsional deformation, etc. Ultimately, by accurately simulating these dynamic behaviors, convergent fluid-solid coupling results can be obtained. With this design, the geometric shape and thickness of the blades can be finely adjusted to effectively disperse the stress, reduce local stress concentration, and reduce the risk of fatigue damage of the blades due to stress concentration. By avoiding the resonant frequency and optimizing the weld arc transition radius, the vibration intensity of the blades during operation is reduced, ensuring the stability of the blades during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic flow chart of a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0041] Figure 2 A schematic diagram of the flow of establishing a wind-wave flow flume model for a method for improving the strength of turbine blades in a water conservancy project provided by the present invention;

[0042] Figure 3A schematic diagram of a hydrodynamic performance test flow of a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0043] Figure 4 A schematic diagram of a blade tip optimization process of a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0044] Figure 5 A schematic diagram of a blade tip optimization process for analyzing a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0045] Figure 6 A schematic flow chart of a fluid-solid coupling control equation for a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0046] Figure 7 A schematic diagram of a process flow of establishing an instantaneous physical model for a method for improving the strength of a turbine blade in a water conservancy project provided by the present invention;

[0047] Figure 8 A schematic diagram of a blade strength and stiffness test process for a method for improving the strength of turbine blades in a water conservancy project provided by the present invention. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] like Figure 1 - Figure 3 As shown, this embodiment provides a technical solution: a method for improving the strength of a turbine blade in a water conservancy project, comprising the following steps:

[0050] S1. Record the shape and cross-sectional shape of the blade;

[0051] S2. Establish wind-wave-current flume model and hydrodynamic performance test;

[0052] In step S2, the specific steps are: constructing autonomous scenes by selecting different geology, terrain and obstacles to explore the interaction between waves and terrain; In step S2, the specific steps are: selecting appropriate experimental instruments to install in the corresponding positions of the flume, such as wave measuring rods and pitot tubes, and correctly installing and calibrating them;

[0053] Use highly plastic materials to shape the predetermined terrain features, and accurately carve out the terrain structure after laying the bottom of the tank. At the same time, place obstacles such as breakwaters or shipwrecks at appropriate locations according to experimental requirements and fix them to prevent movement. Then install measuring equipment such as wave measuring rods and pitot tubes at key locations to monitor water surface height changes and fluid velocity distribution, and perform careful calibration. Finally, perform system debugging and pre-operation, observe the working status of each component, and adjust data acquisition settings to ensure that the required information can be recorded efficiently;

[0054] In step S2, the specific steps are: determine the calibration coefficient, calibrate the relationship between the load and the reading, including the calibration of the torque and speed measuring instrument and the current and voltage signals; in step S2, the specific steps are: create a new test project in the data acquisition and analysis processing system software, balance, clear and record; in step S2, the specific steps are: open the circulating water tank, set the water flow rate to the experimental flow rate; in step S2, the specific steps are: measure the torque, speed, force value of the front and rear strain gauges, and the output of current and voltage of the turbine main shaft under various working conditions; in step S2, the specific steps are: close the circulating water tank, remove the impeller; then open the circulating water tank to the experimental speed, and read the stress value of the strain gauge;

[0055] A new test project was created in the data acquisition and analysis system software, and balancing and zeroing operations were performed to prepare for subsequent tests. Subsequently, the circulating water tank was turned on and set to the water flow speed required for the experiment to simulate the actual operating environment of the turbine. Under various working conditions, the torque, speed, force values ​​of the front and rear strain gauges, and the output of current and voltage of the turbine main shaft were measured in detail. After completing a round of tests, the circulating water tank was closed and the impeller was removed, and then the impeller was reinstalled or adjusted for the next round of tests. Finally, the circulating water tank was turned on again to the experimental speed, and the stress value of the strain gauge was read as the control group data;

[0056] like Figure 1 and Figure 4 , S3, through blade tip optimization, change the interaction between the pressure surface and the suction surface at the blade tip;

[0057] In step S3, the specific steps are: using blade element momentum theory to obtain the distribution of blade torsion angle and chord, and establishing a parametric model of the original rotor based on this; in step S3, the specific steps are: applying the wing knife technology to the design of tidal energy turbine blades; in step S3, the specific steps are: applying the wing tip winglet technology to the design of tidal energy turbine blades; in step S3, the specific steps are: conducting a hydrodynamic performance study on the blade improvement scheme, including comparative analysis of blade surface pressure data, velocity flow field data, and energy capture coefficient Cp data;

[0058] The blade element momentum theory is used to accurately calculate the torsion angle and chord length distribution of the blade, which can predict the performance of the blade under different working conditions. Through this method, a parameterized model can be established to describe the characteristics of the original rotor, providing basic data for subsequent design improvements. Next, the wing knife technology is introduced into the design of tidal energy turbine blades. The wing knife is a device used to reduce vortex-induced drag. It optimizes the flow characteristics by changing the position of the airflow separation point near the tip of the blade. The application of this technology can effectively improve the efficiency of the blade. In addition, the winglet technology is applied to the design of tidal energy turbine blades. The winglet is a small structure located at the tip of the blade, which can further improve the aerodynamic characteristics around the blade, thereby improving the energy efficiency of the entire system. Finally, a comprehensive hydrodynamic performance study is conducted on the improved blades, and data on the pressure distribution on the blade surface, the velocity field information of the surrounding fluid, and the change trend of the overall energy capture coefficient Cp are collected;

[0059] like Figure 1 and Figure 5 , S4, analyze the influence of blade tip optimization on the hydrodynamic performance of the turbine;

[0060] In step S4, the specific steps are: establishing a water turbine tank model test system and a hydrodynamic performance test platform, and performing a large number of tests such as variable pitch angle, variable blade number, and variable flow rate on different types of blades to obtain parameters such as the speed, power, and torque of the turbine under different working conditions; In step S4, the specific steps are: studying the influence of blade tails of different shapes and thicknesses on the performance of the unit, especially the performance under reverse working conditions;

[0061] A turbine flume model test system and hydrodynamic performance test platform were established to simulate the water flow environment under different working conditions, and to conduct detailed tests on various types of blades. The tails of blades with various shapes and thicknesses were studied and compared in detail, especially under reverse working conditions. The flow characteristics and energy loss mechanism of the tail of the blade under reverse working conditions were detected and the data were recorded.

[0062] like Figure 1 and Figure 6 , S5. Establish the fluid-solid coupling control equation of the flexible blade in the fluid;

[0063] In step S5, the specific steps are: establishing a three-dimensional finite element analysis model of the overall runner blade and a single blade of a Francis turbine; in step S5, the specific steps are: using the fluid-solid coupling function in the finite element software to perform modal analysis on the overall runner blade and the single blade, obtaining the self-vibration characteristics of the runner blade and the single blade in the air and in the static fluid, and performing comparative analysis;

[0064] The model was established using software. Then, the fluid-solid coupling function in the finite element analysis software was used to perform modal analysis on the overall runner blades and individual blades. Modal analysis is a method for studying the dynamic characteristics of a structure, which can reveal the natural frequency and vibration mode of the structure and is used to understand the vibration behavior of the blades during operation. Through this analysis, we obtained the self-vibration characteristics of the runner blades and individual blades. In addition, regarding the self-vibration characteristics of the blades in a static fluid, in actual work, the turbine blades operate in a water flow, so it is equally important to understand the dynamic response of the blades in the fluid. By comparing the self-vibration characteristics in the air and in a static fluid, we can deeply understand the influence of the fluid on the vibration behavior of the blades, thereby optimizing the design of the blades.

[0065] like Figure 1 and Figure 7 , S6, solving the blade deformation and establishing the instantaneous physical model;

[0066] In step S6, the specific steps are: on a preset fluid-solid coupling interface, the aerodynamic load / temperature field is transmitted to the structural field, and the geometric deformation / solid temperature is transmitted to the flow field, and the coupled multi-physics field results after convergence are obtained by iterative solution; in step S6, the specific steps are: the flow field and the structural field are iteratively solved in the time domain according to the preset total time length and time step, and the bidirectional fluid-solid coupling solution results that change with the time domain after final convergence are obtained; in step S6, the specific steps are: on a preset fluid-solid coupling interface, the aerodynamic load and geometric deformation are iteratively solved to obtain the coupled multi-physics field results after convergence; in step S6, the specific steps are: according to the blade deformation results, an instantaneous physical model is established to simulate the dynamic behavior of the blade in the fluid, including the flapping, swinging and torsional deformation of the blade;

[0067] On the pre-set fluid-solid coupling interface, the transmission of aerodynamic loads and temperature fields to the structural field is realized, and the geometric deformation and solid temperature are fed back to the flow field. Through iterative solution, the converged coupled multi-physics field results are obtained. These results reflect in detail the stress and deformation of the blades under actual working conditions. Next, the flow field and structural field are iteratively solved in the time domain according to the pre-set total duration and time step. This step is the key to simulating the dynamic response of the blade in a real fluid environment. Through continuous iterative calculations, the final converged bidirectional fluid-solid coupling solution results are obtained, which are used to observe the transient behavior of the blade at different time points. On the pre-set fluid-solid coupling interface, the interaction between the two is accurately simulated to obtain the coupled multi-physics field results. Finally, according to the deformation results of the blades, an instantaneous physical model is established to simulate the dynamic behavior of the blades in the fluid.

[0068] like Figure 1 and Figure 8 , S7, blade strength and stiffness test;

[0069] In step S7, the specific steps are: finding the resonance points that may appear on the blades, and designing the geometric parameters of the blades to avoid these resonance points; in step S7, the specific steps are: according to the stress distribution of the blades, appropriately increasing the thickness of the blades, especially in the high stress area, to improve the bearing capacity of the blades and reduce stress concentration; in step S7, the specific steps are: optimizing the arc transition radius of the weld at the connection between the blades and the upper crown and the lower ring to reduce stress concentration and improve stress distribution; in step S7, the specific steps are: comprehensively measuring the vibration characteristics of the blades of the newly installed unit, including the verification of the frequency dispersion rate and the resonance safety rate, to ensure the optimal shape of the blades during operation;

[0070] First, according to the stress distribution of the blades, the geometric parameters of the blades were finely adjusted to ensure that the blade design could avoid the resonance point. Next, in order to improve the load-bearing capacity of the blades and reduce stress concentration, the thickness of the blades in the high stress area was increased. This measure not only enhanced the structural strength of the blades, but also effectively dispersed the stress and reduced the risk of fatigue damage caused by stress concentration. This targeted reinforcement design enables our blades to maintain stable and reliable performance in harsh working environments. In addition, the arc transition radius of the weld at the connection between the blades and the upper crown and lower ring reduced stress concentration and improved the stress distribution of the entire blade. Finally, the blades of the newly installed units were comprehensively measured to ensure that the blades can maintain the optimal shape during actual operation.

[0071] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for improving the strength of turbine blades in a water conservancy project, characterized in that: The following steps are involved: S1. Record the shape and cross-sectional shape of the blade; S2. Establish wind-wave-current flume model and hydrodynamic performance test; S3, by optimizing the blade tip, changing the interaction between the pressure surface and the suction surface at the blade tip; S4. Analyze the influence of blade tip optimization on the hydrodynamic performance of turbines; S5. Establish the fluid-solid coupling control equation of the flexible blade in the fluid; S6, solving blade deformation and establishing instantaneous physical model; S7. Blade strength and stiffness test.

2. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In step S2, the specific steps are: constructing an autonomous scene by selecting different geology, terrain and obstacles to explore the interaction between waves and terrain; In step S2, the specific steps are: selecting appropriate experimental instruments, such as a wave measuring rod and a pitot tube, and installing them at corresponding positions of the water tank, and performing correct installation and calibration.

3. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In the step S2, the specific steps are: determining the calibration coefficient, calibrating the relationship between the load and the reading, including the calibration of the torque and speed measuring instrument and the current and voltage signals; In step S2, the specific steps are: creating a new test project in the data acquisition and analysis processing system software, performing balancing, clearing and recording; In step S2, the specific steps are: start the circulating water tank and set the water flow rate to the experimental flow rate; In step S2, the specific steps are: measuring the torque, speed, force values ​​of the front and rear strain gauges, and the output of current and voltage of the main shaft of the turbine under various working conditions; In step S2, the specific steps are: closing the circulating water tank and removing the impeller; then opening the circulating water tank to the experimental speed and reading the stress value of the strain gauge.

4. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In step S3, the specific steps are: using blade element momentum theory to obtain the distribution of blade torsion angle and chord, and establishing a parameterized model of the original rotor based on this; In step S3, the specific steps are: applying the blade blade technology to the design of tidal energy turbine blades; In the step S3, the specific steps are: applying the winglet technology to the design of tidal energy turbine blades; In the step S3, the specific steps are: conducting a hydrodynamic performance study on the blade improvement scheme, including comparative analysis of blade surface pressure data, velocity flow field data, and energy capture coefficient Cp data.

5. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In step S4, the specific steps are: establishing a water turbine tank model test system and a hydrodynamic performance test platform, and performing a large number of tests such as variable pitch angle, variable blade number, and variable flow rate on different types of blades to obtain parameters such as speed, power, and torque of the turbine under different working conditions; In step S4, the specific steps are: studying the influence of blade tails of different shapes and thicknesses on the performance of the unit, especially the performance under reverse working conditions.

6. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In the step S5, the specific steps are: establishing a three-dimensional finite element analysis model of the Francis turbine integral runner blade and a single blade; In step S5, the specific steps are: using the fluid-solid coupling function in the finite element software to perform modal analysis on the overall runner blade and the single blade, obtain the self-vibration characteristics of the runner blade and the single blade in the air and in the static fluid, and perform comparative analysis.

7. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In step S6, the specific steps are: on a preset fluid-solid coupling interface, the aerodynamic load / temperature field is transmitted to the structural field, the geometric deformation / solid temperature is transmitted to the flow field, and the converged coupled multi-physics field results are obtained by iterative solution; In step S6, the specific steps are: performing time domain iterative solutions for the flow field and the structural field according to a preset total time length and time step, and obtaining a bidirectional fluid-solid coupling solution result that changes in the time domain after final convergence; In the step S6, the specific steps are: on a preset fluid-solid coupling interface, aerodynamic loads and geometric deformations are iteratively solved to obtain converged coupled multi-physics field results; In step S6, the specific steps are: according to the deformation result of the blade, an instantaneous physical model is established to simulate the dynamic behavior of the blade in the fluid, including the flapping, shimmying and torsional deformation of the blade.

8. The method for improving the strength of turbine blades in a hydraulic project according to claim 1, characterized in that: In step S7, the specific steps are: finding resonance points that may appear on the blade, and designing the geometric parameters of the blade to avoid these resonance points; In step S7, the specific steps are: according to the stress distribution of the blade, appropriately increase the thickness of the blade, especially in the high stress area, so as to improve the bearing capacity of the blade and reduce stress concentration; In step S7, the specific steps are: optimizing the arc transition radius of the weld at the connection between the blade and the upper crown and the lower ring to reduce stress concentration and improve stress distribution; In step S7, the specific steps are: comprehensively measuring the vibration characteristics of the blades of the newly installed unit, including the identification of the frequency dispersion rate and the resonance safety rate, to ensure the optimal shape of the blades during operation.

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