Fan blade crack propagation analysis method and device considering real ocean environment

Abstract

The invention relates to the technical field of ocean engineering and mechanical engineering, in particular to a method and a device for analyzing crack propagation of a fan blade considering a real ocean environment. According to the method, the real marine environment working condition is considered, dynamic simulation analysis is conducted on the fan blade, distribution information of loads borne by the fan blade is determined and loaded on a finite element model of the fan blade, a fatigue hot spot area is determined according to a finite element fatigue damage analysis result, and crack arrangement is conducted. And calculating a stress intensity factor of a crack tip and performing crack propagation simulation according to a finite element analogue simulation result so as to evaluate the fracture damage risk of the fan blade in a real marine environment. The wind turbine blade crack propagation analysis thought under the complex stress condition is provided, equipment faults and risks caused by blade breakage can be prevented, a scientific basis is provided for overhaul and operation and maintenance of a wind turbine, and therefore economic losses caused by failure of the wind turbine blade are reduced.

Description

Technical Field

[0001] The present invention relates to the fields of marine engineering and mechanical engineering, and in particular to a crack propagation analysis method and device for a fan blade taking into account the real marine environment. Background Art

[0002] When floating offshore wind turbine blades are operating in an offshore environment, they are subject to a variety of complex mechanical and environmental factors. These factors include wind loads, gravity loads, wave impacts, temperature changes, and salt spray corrosion. These forces and environmental conditions will cause the blade material to gradually fatigue and age, and may eventually cause fracture. In order to ensure the safety and reliability of the blades, their fracture behavior must be deeply analyzed and studied.

[0003] The excellent mechanical properties and reliable quality of blades are crucial conditions to ensure the continuous and stable operation of wind turbines. In view of the harsh working environment of wind turbines, blades must have high fracture resistance and excellent mechanical properties to withstand continuously changing random loads and sudden extreme conditions (such as the impact of extreme climate phenomena such as tornadoes). Crack propagation behavior The crack propagation rate is usually determined as the stress intensity factor K, which is a function of the crack tip fracture parameters. Therefore, it is of great significance to analyze the crack tip fracture parameters of blades, and it can provide important reference value for the design, manufacturing, optimization and reliability assessment technology of wind turbine blades. Summary of the invention

[0004] In view of this, the present invention provides a crack propagation analysis method and device for wind turbine blades taking into account the real ocean environment, so as to solve the problem in the prior art that crack propagation cannot be accurately assessed, resulting in deviations in the prediction results of blade fracture and damage risks.

[0005] In a first aspect, the present invention provides a crack propagation analysis method for wind turbine blades taking into account the real ocean environment, the method comprising: performing dynamic simulation of wind turbine blades based on real ocean environment parameters under different ocean environment conditions to determine the load distribution information borne by the wind turbine blades; loading the load distribution information into a finite element model of the blades, simulating the fatigue damage process of the blades, and obtaining simulation results; determining fatigue hotspot areas of the blades throughout their life cycle based on a fatigue damage distribution diagram in the simulation results, and arranging cracks in the finite element model based on the fatigue hotspot areas; resetting typical working conditions as new working conditions to perform wind turbine simulation and load calculation, loading the load distribution information of the new working conditions into a finite element model with cracks arranged, resimulating the fatigue damage force loading process of the blades, and obtaining new simulation results; calculating the crack tip fracture parameters of the wind turbine blades based on the new simulation results, and then analyzing the crack propagation.

[0006] In the present invention, the method takes into account the actual marine environment conditions, performs dynamic simulation analysis on the wind turbine blades, determines the load distribution information borne by the wind turbine blades and loads it onto the finite element model of the wind turbine blades, and determines the fatigue hotspot area and arranges the cracks based on the finite element fatigue damage analysis results. Through the finite element simulation results, the stress intensity factor at the crack tip is calculated and crack propagation simulation is performed to assess the risk of fracture and damage of the wind turbine blades in a real marine environment. An analysis idea for crack propagation of wind turbine blades under complex stress conditions is proposed, which can prevent equipment failures and risks caused by blade fractures, provide a scientific basis for the inspection and maintenance of wind turbines, and thus reduce the economic losses caused by wind turbine blade failures.

[0007] In an optional embodiment, a dynamic simulation of wind turbine blades is performed based on real ocean environmental parameters under different ocean environmental conditions to determine the load distribution information borne by the wind turbine blades, including: determining the wind speed range of the wind turbine according to the wind speed power curve of the wind turbine, and dividing the wind speed range into a preset number of wind speed intervals; calibrating turbulence intensity parameters and wave parameters based on the real ocean environment under different ocean environmental conditions, and determining wind field parameters for each wind speed interval based on the wave parameters and the wind speed parameters determined by the turbulence intensity parameters; generating a wind field file based on the wind field parameters for each wind speed interval and the wind turbine model parameters; performing dynamic simulation and load calculation according to the wind field file and environmental parameters to obtain the load information of the wind turbine blades.

[0008] In the present invention, by determining the wind speed range of the fan and dividing the wind speed range into multiple wind speed intervals, each wind speed interval can be determined as a calculation condition for fan simulation, and a wind field file is generated based on the wind field parameters and fan model parameters of each wind speed interval, providing a data basis for load calculation. In addition, when performing load calculation, in addition to the wind field file, environmental parameters are further considered, so that the determination of the load is more in line with the actual situation.

[0009] In an optional implementation, dynamic simulation and load calculation are performed according to wind field files and environmental parameters to obtain load information of wind turbine blades, including: simulating the overall operating response of the wind turbine based on the wind field files and environmental parameters to obtain simulation results; determining the load distribution and time history of the wind turbine blades based on blade element momentum theory, beam model and simulation results; converting the load distribution and time history into equivalent cyclic loads to obtain load information of the wind turbine blades.

[0010] In an optional embodiment, fatigue hot spots throughout the life cycle of the blade are determined according to the fatigue damage distribution map in the simulation results, and crack layout of the finite element model is performed based on the fatigue hot spots, including: using finite element software to obtain fatigue damage distribution maps in simulation results under different marine environment conditions, and determining fatigue hot spots throughout the life cycle of the blade; and performing crack layout of the finite element model in the fatigue hot spots.

[0011] In an optional embodiment, the finite element model includes multiple units, and the cracks are arranged using the following process: at the intersection of units, new nodes with exactly the same geometric position as the original nodes are generated; the units adjacent to the new nodes are redefined using the new nodes to generate cracks.

[0012] In the present invention, cracks are generated in this way so that in the upper and lower adjacent unit sets, the lower node of the upper unit and the upper node of the lower unit coincide in spatial position, but are discontinuous in geometry and mesh, thereby ensuring the authenticity of the crack setting.

[0013] In an optional embodiment, the crack propagation of the wind turbine blade is analyzed according to the new simulation results, including: analyzing the blade fracture parameters according to the new simulation results to obtain a first analysis result, the blade fracture parameters including the stress intensity factor; analyzing the blade crack propagation behavior based on the first analysis result to obtain a second analysis result; and performing a simulation analysis on the blade crack propagation based on the first analysis result and the second analysis result.

[0014] In an optional embodiment, the stress intensity factor is determined based on the strain energy release rate and the elastic modulus under different wind speed intervals; the second analysis result includes the crack growth rate and the stress intensity range; based on the first analysis result and the second analysis result, a simulation analysis is performed on the blade crack growth, including: arranging spring units with variable stiffness between adjacent units at the crack tip according to a preset crack growth path; based on the stress intensity factor, the crack growth rate and the stress intensity range, adjusting the stiffness of the spring unit to perform multiple cycles of simulation to obtain the crack growth analysis result on the finite element model.

[0015] In a second aspect, the present invention provides a crack extension analysis device for wind turbine blades taking into account the real ocean environment, the device comprising: a load distribution determination module, used to perform dynamic simulation of wind turbine blades based on real ocean environment parameters under different ocean environment conditions, and determine the load distribution information borne by the wind turbine blades; a loading simulation module, used to load the load distribution information into a finite element model of the blades, simulate the fatigue damage process of the blades, and obtain simulation results; a crack arrangement module, used to determine the fatigue hotspot areas of the blades throughout their life cycle according to the fatigue damage distribution diagram in the simulation results, and arrange cracks in the finite element model based on the fatigue hotspot areas; a new operating condition simulation module, used to reset a typical operating condition as a new operating condition for wind turbine simulation and load calculation, load the load distribution information of the new operating condition into a finite element model with cracks arranged, re-simulate the fatigue damage process of the blades, and obtain new simulation results; an extension analysis module, used to analyze the crack extension of the wind turbine blades according to the new simulation results.

[0016] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the crack propagation analysis method for wind turbine blades taking into account the real ocean environment of the above-mentioned first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0017] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the crack propagation analysis method for wind turbine blades taking into account the real ocean environment of the above-mentioned first aspect or any corresponding embodiment.

[0018] In a fifth aspect, the present invention provides a computer program product, comprising computer instructions for causing a computer to execute the crack propagation analysis method for a wind turbine blade taking into account the real marine environment according to the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 is a flow chart of a crack propagation analysis method for a wind turbine blade taking into account a real marine environment according to an embodiment of the present invention;

[0021] Figure 2 is a schematic diagram of coupling all nodes in a cross section with a reference point of the aerodynamic center of the cross section according to an embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of load application of a finite element model according to an embodiment of the present invention;

[0023] Figure 4 is a schematic diagram of crack setting according to an embodiment of the present invention;

[0024] Figure 5 is a schematic diagram of crack expansion with cycles according to an embodiment of the present invention;

[0025] FIG6(a), FIG6(b) and FIG6(c) are schematic diagrams of cracks of different lengths according to an embodiment of the present invention;

[0026] Figure 7 is a flow chart of another crack propagation analysis method for a wind turbine blade taking into account the real marine environment according to an embodiment of the present invention;

[0027] Figure 8 is a structural block diagram of a crack propagation analysis device for a wind turbine blade taking into account a real marine environment according to an embodiment of the present invention;

[0028] Fig. 9 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0030] According to an embodiment of the present invention, an embodiment of a crack propagation analysis method for a wind turbine blade taking into account the real marine environment is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in an order different from that shown here.

[0031] In this embodiment, a crack propagation analysis method for a wind turbine blade considering the real marine environment is provided, which can be used in electronic devices such as computers, mobile phones, tablet computers, etc. Figure 1 is a flow chart of a crack propagation analysis method for a wind turbine blade considering a real marine environment according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0032] Step S101, based on the real ocean environment parameters under different ocean environment conditions, the wind turbine blades are dynamically simulated to determine the load distribution information borne by the wind turbine blades. Specifically, when the wind turbine blades are dynamically simulated, it can be implemented through a wind turbine simulation program, which is based on the momentum cloud method and the law of conservation of momentum, and is used to calculate the translation and rotational motion of the floating wind turbine under the combined wind and wave loads. Among them, during the simulation, the relevant parameters of the wind turbine can be first obtained based on the real ocean environment under different ocean environment conditions, and then the simulation scene of the wind turbine can be configured, and then the relevant functional modules in the wind turbine can be used to perform dynamic simulation analysis to determine the load distribution information borne by the wind turbine blades.

[0033] Step S102, load the load distribution information to the finite element model of the blade, simulate the fatigue damage process of the blade, and obtain the simulation result. Wherein, before the load distribution information is loaded, the finite element modeling of the blade can be performed first, for example, a three-dimensional model of the blade can be constructed first, and then the three-dimensional model can be imported into the finite element modeling software to perform finite element modeling of the blade. In this embodiment, the fan blade is modeled using shell elements to improve the calculation efficiency while maintaining a high accuracy. At the same time, a single grid size is selected during modeling and divided according to 0.1m. In addition, before modeling, the skin material parameters of the blade need to be set. In this embodiment, the skin material parameters of the blade select the fiberglass commonly used in the industry (for example, the fiberglass material of the model FRP, whose elastic modulus is 20GPa, Poisson's ratio is 0.15, and the density is 2000kg / m3), and the web is usually made of carbon fiber material (for example, the carbon fiber material of the model T700, whose elastic modulus is 250GPa, Poisson's ratio is 0.3, and the density is 1800kg / m3).

[0034] After the finite element model of the blade is constructed, the root nodes of the blade finite element model are fully constrained according to the rigid connection between the blade root and the hub. Starting from the root of the blade, the blade is divided into m airfoil sections every 2 meters (m is determined by the blade length), and all nodes in the section are coupled with the reference point of the aerodynamic center of the section, such as Figure 2 As shown (including reference points RP-5, RP-6, and RP-7), this coupling allows relative deformation between the cross-sectional nodes.

[0035] Therefore, when loading load information, such as Figure 3 As shown, the load distribution information can be loaded onto m airfoil sections in finite element analysis software (such as ABAQUS, ANASYS, etc.), and finite element analysis calculations can be performed to simulate the force loading process of the blade in a real working environment.

[0036] Step S103, according to the fatigue damage distribution map in the simulation results, determine the fatigue hotspot area of ​​the blade throughout its life cycle, and arrange cracks in the finite element model based on the fatigue hotspot area. Specifically, since the fatigue damage process of the blade is simulated in the finite element software, the stress concentration area of ​​the blade can be determined by the simulation results of the finite element analysis, and the fatigue damage distribution and the fatigue damage area map can be further determined. Assuming that the fatigue damage area is the first crack caused by structural fatigue, the crack arrangement of the finite element model can be performed based on the fatigue damage area. Among them, when arranging cracks, cracks can also be set in the constructed finite element model according to the unit structure in the model. And since the simulation results are obtained through different marine environment conditions, by setting conditions covering the entire life cycle of the blade, the fatigue hotspot area of ​​the blade throughout its life cycle can be determined through the simulation results.

[0037] Step S104, reset the typical working condition as a new working condition to perform wind turbine simulation and load calculation, load the load distribution information of the new working condition into the finite element model arranged with cracks, re-simulate the blade fatigue damage force loading process, and obtain new simulation results. Specifically, after cracks are arranged in the finite element model of the blade, the typical working condition can be reset as a new working condition to perform wind turbine simulation and load calculation. The calculation process refers to the process of the above-mentioned step S101. After obtaining the load distribution information of the new working condition, load it into the finite element model arranged with cracks, re-simulate the blade fatigue damage process, and obtain new simulation results. It should be noted that the typical working condition and the marine environment working condition in step S101 may be the same or different.

[0038] Step S105, analyzing the crack propagation of the fan blade according to the new simulation results. Specifically, since the simulation results are obtained by simulating the fatigue damage process of the blade, the fatigue damage of the blade can be analyzed by the new simulation results, and the crack tip stress intensity factor is a key parameter in fracture mechanics, which is used to describe the stress concentration degree at the crack tip and determine whether the crack will propagate. Therefore, when analyzing the crack propagation of the fan blade, this embodiment mainly analyzes the fracture condition of the crack tip and the crack propagation condition.

[0039] The crack propagation analysis method for wind turbine blades that takes into account the real marine environment provided by the embodiment of the present invention takes into account the real marine environment conditions, performs dynamic simulation analysis on the wind turbine blades, determines the load distribution information borne by the wind turbine blades and loads it onto the finite element model of the wind turbine blades, and determines the fatigue hotspot area and arranges the cracks based on the finite element fatigue damage analysis results. Through the finite element simulation results, the stress intensity factor at the crack tip is calculated and crack propagation simulation is performed to evaluate the risk of fracture and damage of the wind turbine blades in the real marine environment. An analysis idea for crack propagation of wind turbine blades under complex stress conditions is proposed, which can prevent equipment failures and risks caused by blade fractures, provide a scientific basis for the inspection and maintenance of wind turbines, and thus reduce the economic losses caused by the failure of wind turbine blades.

[0040] In this embodiment, a crack propagation analysis method for a wind turbine blade considering the real marine environment is provided, and the process includes the following steps:

[0041] Step S201 , performing dynamic simulation on the wind turbine blades based on real ocean environmental parameters under different ocean environmental conditions, and determining load distribution information borne by the wind turbine blades.

[0042] Specifically, the above step S201 includes:

[0043] Step S2011, determine the wind speed range of the wind turbine according to the wind speed power curve of the wind turbine, and divide the wind speed range into a preset number of wind speed intervals; wherein the wind speed power curve of the wind turbine describes the relationship between wind speed and power, and the curve can be obtained through theoretical calculation, simulation, on-site measurement or product description. After determining the wind speed power curve, the wind speed range of the wind turbine simulation calculation condition can be reasonably set according to the cut-in speed and cut-out speed at the height of the wind turbine hub. For example, the lower limit of the wind speed range can be determined by subtracting 5% to 10% of the cut-in wind speed from the cut-in wind speed, and the lower limit of the wind speed range can be determined by adding 5% to 10% of the cut-out wind speed to the cut-out wind speed.

[0044] Among them, before dividing the wind speed interval, the number of divided wind speed intervals is first determined. Since each wind speed interval needs to be analyzed as a calculation condition for wind turbine simulation after division, the number of wind speed intervals can be determined by comprehensively considering the computing resources required for simulation and the time required for simulation. After determining the number of wind speed intervals, the wind speed range can be divided by the number of wind speed intervals to determine the upper and lower limits of each wind speed interval, and then the wind speed interval is divided according to the upper and lower limits of each wind speed interval.

[0045] Step S2012, calibrating the turbulence intensity parameters and wave parameters based on the real ocean environment under different ocean environment conditions, and determining the wind field parameters of each wind speed interval based on the wave parameters and the wind speed parameters determined by the turbulence intensity parameters.

[0046] The wind field parameters of the wind speed interval include parameters such as the average wind speed of the wind speed interval and the wind speed standard deviation. Specifically, the average wind speed of the wind speed interval can be determined by the average value of the upper and lower limits of the wind speed interval. Thus, the average wind speed μ1, μ2, …, μ representing the wind speed interval can be determined one by one according to the upper and lower limits of each wind speed interval. k (k represents the number of wind speed intervals). The wind speed standard deviation can be determined by using the turbulence model calculation formula (such as the NTM turbulence model) recommended by the IEC (International Electrotechnical Commission) specification to determine the wind speed standard deviation σ1, σ2, ..., σ representing the wind speed interval. k For example, if the NTM turbulence model recommended by the IEC specification is selected, the wind speed standard deviation is calculated according to the following formula:

[0047] σ=I ref (0.75μ+5.6) Formula 1

[0048] Among them, μ represents the average wind speed, and the turbulence intensity parameter I refThe value can be selected by referring to the recommended values ​​given by Model A, B, and C recommended by the IEC specification.

[0049] In offshore areas where IEC standards are not applicable, buoy data can be used as a reference for calculation, such as the buoy data provided in the relevant technology for analysis. By analyzing the buoy data, the average wind speed μ in each wind speed interval can be calculated. i and wind speed standard deviation σ i The linear relationship between the turbulence intensity parameter I ref The value is recalibrated to conform to the actual marine environment conditions.

[0050] Similarly, the wave parameters corresponding to each wind speed interval can be obtained by analyzing the buoy data or estimated using the wind-wave coupling method in fully developed sea areas.

[0051] Step S2013, generating a wind field file based on the wind field parameters and wind turbine model parameters of each wind speed interval;

[0052] Specifically, the wind turbine model parameters can be determined according to the wind turbine type. For example, for a floating wind turbine model, the hub height, blade length, etc. are selected as wind turbine model parameters. After determining the wind field parameters and wind turbine model parameters, a wind field simulation software such as TurbSim can be used to generate a Gaussian wind field file corresponding to the wind speed range. It is generally believed that the short-term wind speed distribution satisfies a stationary random process, so the length of the wind field file and the wind turbine simulation time are generally not more than 20 minutes.

[0053] Step S2014, dynamic simulation and load calculation are performed according to the wind field file and environmental parameters to obtain the load information of the wind turbine blades. Before performing the load calculation, it is necessary to determine the environmental parameters of the wind turbine. For example, when the wind turbine in this embodiment is a floating offshore wind turbine, the environmental parameters include wave parameters, etc. The wave parameters include the significant wave height and the average peak period. Specifically, the wave parameters corresponding to the wind speed range can be determined by the fully developed sea state calculation formula or other methods, that is, the significant wave height H s (Significant Wave Height) and peak period T p For example, if the fully developed sea condition calculation formula is selected, the average wind speed at the hub height is first converted to a reference height of 19.5 meters, and then the significant wave height and average peak period are calculated according to the relevant formula.

[0054] Specifically, the above step S2014 includes:

[0055] Step a1, simulate the overall operation response of the wind turbine based on the wind field file and environmental parameters to obtain simulation results; specifically, the wind field file and environmental parameters of each wind speed range can be input into a wind turbine simulation program, such as the FAST program, to solve the overall operation response of the wind turbine, and obtain the corresponding displacement, velocity, acceleration and other simulation results of each component of the wind turbine in each wind speed range.

[0056] Step a2, determine the load distribution and time history of the wind turbine blades based on the blade element momentum theory, the beam model and the simulation results; wherein, the blade element momentum theory can calculate the theoretical lift and drag of the blades at different wind speeds. When calculating, it is necessary to divide the blade into multiple blade element segments, each of which can be regarded as a small lifting body, and calculate the aerodynamic load of each blade element by considering factors such as wind speed and angle of attack. The beam model regards the blade as a beam, and applies beam theory (such as Euler-Bernoulli beam theory or Timoshenko beam theory) to analyze the structural response. When establishing the beam model, it is also necessary to consider factors such as the mass distribution, stiffness distribution, and boundary conditions of the blade to establish a set of dynamic equations.

[0057] Therefore, when determining the load distribution and time history, the aerodynamic load calculated by the blade element momentum theory can be applied to the beam model, and the coupled aeroelastic dynamics analysis simulation can be performed using simulation software and combined with the simulation results. After the simulation is completed, the load distribution of the blade (such as the distribution of bending moment, shear force, and torque along the length of the blade) and the time history are extracted from the output results.

[0058] Step a3, convert the load distribution and time history into equivalent cyclic load to obtain the load information of the fan blade. Specifically, when converting, it is necessary to first divide the load into two categories, forward and reverse, according to the load distribution and time history, and then use the rain flow counting algorithm to analyze the time history of each type of load to identify all load cycles. Then, use the equivalent load spectrum method to convert it into an equivalent cyclic load to obtain the load information of the fan blade.

[0059] Step S202, load the load distribution information into the finite element model of the blade, simulate the fatigue damage process of the blade, and obtain the simulation result. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0060] Step S203, determining fatigue hotspot areas of the blade throughout its life cycle according to the fatigue damage distribution diagram in the simulation results, and performing crack arrangement of the finite element model based on the fatigue hotspot areas;

[0061] Specifically, the above step S203 includes:

[0062] Step S2031, using finite element software to obtain the fatigue damage distribution map in the simulation results under different marine environment conditions, and determine the fatigue hot spots of the blade throughout its life cycle; specifically, through finite element analysis, the stress distribution of the blade in each wind speed range can be solved. After determining the stress distribution, a Mises stress cloud map can be generated in the post-processing module of the finite element analysis software, which can intuitively display the stress distribution inside the blade in each wind speed range. Further, the fatigue damage distribution map and the fatigue hot spots of the blade throughout its life cycle can be determined through finite element analysis.

[0063] Step S2032, arrange cracks of the finite element model in the fatigue hotspot area. In addition to arranging cracks in the fatigue hotspot area, cracks can also be arranged in some preset areas. The preset area includes the area that bears the most intensive load (tip, leading edge), transition area (for example, the transition area from the cylinder to the airfoil and layer drop), dissimilar and interface-containing areas (with adhesive layer, such as the trailing edge). In this embodiment, the locations for arranging cracks include the root of the blade, 1 / 3 and 2 / 3 of the distance from the root of the blade in the span direction, the maximum chord length and the upper spar cover, and the trailing edge and leading edge of the high-pressure side.

[0064] In an optional implementation, when arranging cracks, a new node with the same geometric position as the original node may be generated at the intersection of the units; the units adjacent to the new node may be redefined with the new node to generate cracks.

[0065] Specifically, in order to simulate the structural damage state under real working conditions, a transverse crack with a length of a is set in the crack area. This can further evaluate the impact of these cracks on the overall strength and life of the blade, thereby providing a reliable basis for the design optimization of the wind turbine blade. The specific process of crack setting includes: Figure 4 As shown in the figure, at the n nodes where the elements intersect, n new nodes with the same geometric positions as the original nodes are generated, and the n+1 upper (or lower) elements adjacent to them are redefined with the newly generated n nodes to generate cracks. Through this method, in the upper and lower adjacent element sets, the lower nodes of the upper element and the upper nodes of the lower element coincide in spatial position, but are discontinuous in geometry and mesh.

[0066] Step S204: Reset the typical working condition as a new working condition to perform wind turbine simulation and load calculation, load the load distribution information of the new working condition to the finite element model with cracks, re-simulate the blade fatigue damage force loading process, and obtain new simulation results. Figure 1 Step S104 of the illustrated embodiment will not be described in detail here.

[0067] Step S205: analyzing the crack propagation of the wind turbine blade according to the new simulation results.

[0068] Specifically, the above step S205 includes:

[0069] Step S2051: analyzing the blade fracture parameters according to the new simulation results to obtain a first analysis result, wherein the blade fracture parameters include a stress intensity factor, which is determined based on the strain energy release rate and elastic modulus under different wind speed intervals.

[0070] Specifically, the crack tip stress intensity factor is a key parameter in fracture mechanics, which is used to describe the stress concentration at the crack tip and determine whether the crack will expand. The load calculated by the wind turbine simulation is reapplied to the finite element model of the wind turbine blade with a preset crack. The strain energy release rate G of the wind speed model in different wind speed ranges is calculated according to formula 2. I (Take type I crack as an example), and then convert it into stress intensity factor K I (Formula 3), and obtain its changing trend over time and the maximum value K max and minimum value K min .

[0071]

[0072] In the formula, G I represents the strain energy release rate, F yI represents the crack tip unit node force, Δv 3,4 represents the displacement of the crack tip unit node, B represents the thickness, and Δa represents the crack extension.

[0073]

[0074] In the formula, E represents the elastic modulus, K I represents the stress intensity factor.

[0075] Step S2052: Analyze the crack propagation behavior of the blade based on the first analysis result to obtain a second analysis result. Specifically, according to the above-mentioned calculation method of the stress intensity factor, its change trend over time and the maximum value K can be obtained. max and minimum value K min Then according to the maximum value K max and minimum value K min The stress intensity range is obtained by the difference ΔK. The crack growth behavior can be described based on the relationship between the crack growth rate and the stress intensity range. Therefore, after obtaining the stress intensity range, the crack growth rate can be determined based on this relationship, and then the crack growth behavior can be analyzed.

[0076] Among them, the crack growth rate da / dN can be determined by the Paris theorem, that is, at this time, the crack growth rate da / dN is calculated using the following formula:

[0077]

[0078] In addition, the crack growth rate can also be calculated based on the Forman formula, which is a generalization of the Paris formula and describes three regions at the same time. The Forman formula can be specifically expressed as follows:

[0079]

[0080] Where: C, n, p and q are experimentally determined material constants; f depends on the stress ratio R; ΔK th is the threshold value; K IC is the critical stress intensity factor.

[0081] Step S2053, based on the first analysis result and the second analysis result, a simulation analysis is performed on the blade crack propagation. The simulation analysis process includes: arranging spring units with variable stiffness between adjacent units at the crack tip according to a preset crack propagation path; adjusting the stiffness of the spring unit based on the stress intensity factor, crack propagation rate and stress intensity range, performing multiple cycles of simulation, and obtaining crack propagation analysis results on the finite element model.

[0082] Specifically, considering the crack propagation direction, spring units with variable stiffness are arranged between adjacent units at the crack tip according to the estimated crack propagation path, such as Figure 5 As shown in Figure 2, as the number of cycles increases, the stiffness coefficient of the spring unit decreases continuously. When the amplitude of the stress intensity factor ΔK at the crack tip is greater than the fracture threshold value K th When , the spring unit stiffness decreases to 0, the spring breaks, and the crack extends one finite element mesh unit along the preset direction. This process repeats and the crack length increases continuously, as shown in Figure 6(a), Figure 6(b), and Figure 6(c).

[0083] As a specific application example of the embodiment of the present invention, Figure 7 As shown in the figure, the crack propagation analysis method of the wind turbine blade considering the real marine environment can be implemented by the following process:

[0084] 1. Configure calculation conditions.

[0085] 1.1, Divide the calculation conditions.

[0086] According to the cut-in speed and cut-out speed at the hub height of the wind turbine shown in the wind power curve of the wind turbine, the wind speed range of the wind turbine simulation calculation condition is reasonably set. Taking into account the computing resources and simulation time, the hub height wind speed range covered by the wind turbine simulation analysis is divided into k wind speed intervals, and each wind speed interval corresponds to a calculation condition of the wind turbine simulation.

[0087] 1.2, Estimate marine environmental parameters.

[0088] According to the upper and lower limits of each wind speed interval, the average wind speed μ1, μ2, …, μ representing the wind speed interval is determined one by one. k , the wind speed standard deviation σ1, σ2, …, σ representing the wind speed range is determined by the turbulence model calculation formula recommended by the IEC specification (such as the NTM turbulence model). k For example, if the NTM turbulence model recommended by the IEC specification is selected, the wind speed standard deviation is calculated according to Formula 1.

[0089] σ=I ref (0.75μ+5.6) (Formula 1)

[0090] Among them, the turbulence intensity parameter I ref The value can be selected by referring to the recommended values ​​given by Model A, B, and C recommended by the IEC specification.

[0091] In offshore areas where IEC standards are not applicable, buoy data can be used as a reference for calculations, such as buoy data provided by relevant technologies. By analyzing the buoy data, the average wind speed μ in each wind speed interval can be calculated. i and wind speed standard deviation σ i The previous linear relationship for the turbulence intensity parameter I ref The value is recalibrated to conform to the real marine environment industrial control.

[0092] Similarly, the wave parameters corresponding to each wind speed interval can be obtained by analyzing the buoy data or estimated using the wind-wave coupling method in fully developed sea areas.

[0093] 1.3, Configure wind farm files.

[0094] For each wind speed interval, combined with the wind field model parameters, that is, the average wind speed μ i and wind speed standard deviation σ i , and the model parameters of the floating wind turbine, such as hub height, blade length, etc., use wind field simulation software, such as TurbSim, to generate a Gaussian wind field file for the corresponding wind speed range. It is generally believed that the short-term wind speed distribution satisfies a stationary random process, so the length of the wind field file and the wind turbine simulation time are generally not more than 20 minutes.

[0095] 2. Finite element modeling of blades. Finite element modeling of blades includes blade structure modeling, blade material setting and blade mesh division.

[0096] The skin material parameters of the blade are selected from the fiberglass commonly used in the industry (for example, the fiberglass material of model FRP, with an elastic modulus of 20GPa, a Poisson's ratio of 0.15, and a density of 2000kg / m3), and the web is usually made of carbon fiber material (for example, the carbon fiber material of model T700, with an elastic modulus of 250GPa, a Poisson's ratio of 0.3, and a density of 1800kg / m3). Compared with the solid body, the shell element can significantly improve the calculation efficiency while maintaining a high accuracy. Therefore, the shell element is selected to model the fan blade, and the single grid size is divided according to 0.1m. According to the rigid connection between the fan blade root and the hub, the root node of the blade finite element model is fully constrained. Starting from the root of the blade, the blade is divided into m airfoil sections every 2 meters (m is determined by the blade length), and all nodes in the section are coupled with the reference point of the aerodynamic center of the section. This coupling allows relative deformation between the section nodes.

[0097] 3. Fan dynamics simulation. Fan dynamics simulation includes solving the overall motion response of the fan, deriving the blade interface load time history, and calculating the blade deformation and force.

[0098] Substitute the wind field file and wave parameters in step 1.3 into the wind turbine simulation program, solve the overall motion response of the wind turbine, and obtain the corresponding displacement, velocity, acceleration and other simulation results of each component of the wind turbine. Through the blade element momentum theory (BladeElement Method) and the beam model (Beam Model) combined with the simulation results, solve the load distribution and time history of the wind turbine blades. Convert the calculated load time history of each section into an equivalent cyclic load, load the processed load onto m airfoil sections through finite element analysis software (such as ABAQUS, ANASYS, etc.), and perform finite element analysis calculations to simulate the blade force loading process in a real working environment.

[0099] 4. Blade crack arrangement. Blade crack arrangement includes calculating blade fatigue damage, determining fatigue hotspot areas, and crack arrangement of finite element models.

[0100] It is generally believed that fatigue damage is prone to occur at the root of the blade, about 1 / 3 and 2 / 3 of the distance from the root of the blade in the span direction, the maximum chord length and the upper spar cover, and the high-pressure side trailing edge and leading edge, thus leading to fracture. Through finite element analysis of wind turbine blades, the distribution of blade fatigue loss under different working conditions is comprehensively considered to determine the crack layout area.

[0101] In order to simulate the structural damage state under real working conditions, a transverse crack with a length of a is set in the crack area. This type of setting is used to further evaluate the impact of these cracks on the overall strength and life of the blade, and then provide a reliable basis for the design optimization of wind turbine blades. The specific process is: at the n nodes where the units intersect, n new nodes with exactly the same geometric positions as the original nodes are generated, and the n+1 upper (or lower) units adjacent to them are redefined with the newly generated n nodes to generate cracks. Through this method, in the upper and lower adjacent unit sets, the lower node of the upper unit and the upper node of the lower unit coincide in spatial position, but are discontinuous in geometry and mesh.

[0102] 5. Crack propagation analysis. Crack propagation analysis includes finite element simulation analysis of crack tip, calculation of fracture parameters at crack tip and crack propagation rate.

[0103] The stress intensity factor at the crack tip is a key parameter in fracture mechanics, which is used to describe the stress concentration at the crack tip and determine whether the crack will expand. The load calculated by the wind turbine simulation under the new working condition is reapplied to the finite element model of the wind turbine blade with a preset crack. The strain energy release rate G is calculated under different wind speed ranges. I (Take type I crack as an example), and then convert it into stress intensity factor K I (Formula 3), and obtain its changing trend over time and the maximum value K max and minimum value K min .

[0104] The crack growth behavior can be described by the relationship between the cyclic crack growth rate da / dN and the stress intensity range ΔK. When the intensity factor ΔK is less than its critical value K IC When , the crack growth rate da / dN can be determined by the Paris theorem. The Forman formula is a generalization of the Paris formula, which describes three regions at the same time, that is, the Forman formula can be used to analyze the crack growth behavior of other regions.

[0105] Considering the crack propagation direction, spring units with variable stiffness are arranged between adjacent units at the crack tip according to the estimated crack propagation path. As the number of cycles increases, the spring unit stiffness coefficient decreases continuously. When the amplitude of the stress intensity factor ΔK at the crack tip is greater than the fracture threshold value K th When , the spring unit stiffness is reduced to 0, the spring breaks, and the crack extends one finite element mesh unit along the preset direction. This cycle repeats, and the crack length continues to increase.

[0106] In this embodiment, a crack propagation analysis device for a wind turbine blade taking into account the real marine environment is also provided, and the device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0107] This embodiment provides a crack propagation analysis device for a wind turbine blade that takes into account the real marine environment. Figure 8 As shown, including:

[0108] The load determination module 81 is used to perform dynamic simulation on the wind turbine blades based on the real marine environment parameters under different marine environment conditions to determine the load distribution information borne by the wind turbine blades.

[0109] The simulation module 82 is used to load the load distribution information into the finite element model of the blade, simulate the fatigue damage process of the blade, and obtain the simulation result.

[0110] The crack arrangement module 83 is used to determine the fatigue hotspot area of ​​the blade throughout its life cycle according to the fatigue damage distribution diagram in the simulation results, and to arrange cracks in the finite element model based on the fatigue hotspot area.

[0111] The re-simulation module 84 is used to reset the typical working condition as a new working condition for wind turbine simulation and load calculation, load the load distribution information of the new working condition into the finite element model with cracks, re-simulate the blade fatigue damage process, and obtain a new simulation result.

[0112] The expansion analysis module 85 is used to analyze the crack expansion of the wind turbine blade according to the new simulation results.

[0113] In an optional embodiment, the load determination module includes: a wind speed division module, which is used to determine the wind speed range of the wind turbine according to the wind speed power curve of the wind turbine, and divide the wind speed range into a preset number of wind speed intervals; a wind field parameter determination module, which is used to calibrate the turbulence intensity parameters and wave parameters based on the real ocean environment under different ocean environment conditions, and determine the wind field parameters of each wind speed interval based on the wave parameters and the wind speed parameters determined by the turbulence intensity parameters; a wind field file generation module, which is used to generate a wind field file based on the wind field parameters of each wind speed interval and the wind turbine model parameters; a load determination submodule, which is used to perform dynamic simulation and load calculation according to the wind field file and environmental parameters to obtain the load distribution information of the wind turbine blades.

[0114] In an optional implementation, the load determination submodule is specifically used to: simulate the overall operating response of the wind turbine based on the wind field file and environmental parameters to obtain simulation results; determine the load distribution and time history of the wind turbine blades based on blade element momentum theory, beam model and simulation results; convert the load distribution and time history into equivalent cyclic loads to obtain load information of the wind turbine blades.

[0115] In an optional embodiment, the crack arrangement module is specifically used to use finite element software to obtain fatigue damage distribution diagrams in simulation results under different marine environment conditions, determine fatigue hotspot areas throughout the life cycle of the blade, and perform crack arrangement of the finite element model in the fatigue hotspot areas.

[0116] In an optional embodiment, the finite element model includes multiple units, and the cracks are arranged using the following process: at the intersection of units, new nodes with exactly the same geometric position as the original nodes are generated; the units adjacent to the new nodes are redefined using the new nodes to generate cracks.

[0117] In an optional embodiment, the extended analysis module includes: a first molecular module, used to analyze the blade fracture parameters according to the new simulation results to obtain a first analysis result, the blade fracture parameters include a stress intensity factor; a second analysis module, used to analyze the blade crack extension behavior based on the first analysis result to obtain a second analysis result; a simulation analysis module, used to perform simulation analysis on the blade crack extension based on the first analysis result and the second analysis result.

[0118] In an optional embodiment, the stress intensity factor is determined based on the strain energy release rate and the elastic modulus under different wind speed intervals; the second analysis result includes the crack growth rate and the stress intensity range; the simulation analysis module is specifically used to arrange spring units with variable stiffness between adjacent units at the crack tip according to a preset crack growth path; based on the stress intensity factor, the crack growth rate and the stress intensity range, the stiffness of the spring unit is adjusted to perform multiple cycles of simulation to obtain the crack growth analysis results on the finite element model.

[0119] The further functional description of each of the above modules is the same as that of the above corresponding embodiments and will not be repeated here.

[0120] The embodiment of the present invention also provides a computer device having the above Figure 8 The crack growth analysis device for wind turbine blades considering the real marine environment is shown.

[0121] See also Fig. 9 , Fig. 9 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig. 9As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig. 9 A processor 10 is taken as an example.

[0122] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0123] The memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0124] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the use of a computer device based on the presentation of a small program landing page, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0125] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0126] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0127] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0128] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0129] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A crack propagation analysis method for wind turbine blades considering the real marine environment, characterized in that: The method comprises: Based on the real marine environmental parameters under different marine environmental conditions, the dynamic simulation of the wind turbine blades is carried out to determine the load distribution information borne by the wind turbine blades; The load distribution information is loaded into a finite element model of the blade, and the fatigue damage process of the blade is simulated to obtain a simulation result; According to the fatigue damage distribution map in the simulation results, the fatigue hotspot areas of the blade throughout its life cycle are determined, and the crack arrangement of the finite element model is performed based on the fatigue hotspot areas; Reset the typical working condition as a new working condition for wind turbine simulation and load calculation, load the load distribution information of the new working condition to the finite element model with cracks, re-simulate the blade fatigue damage process, and obtain new simulation results; Analyze crack growth in wind turbine blades based on new simulation results.

2. The method according to claim 1, characterized in that Based on the real marine environmental parameters under different marine environmental conditions, the dynamic simulation of the wind turbine blades is carried out to determine the load distribution information borne by the wind turbine blades, including: Determine a wind speed range of the wind turbine according to a wind speed power curve of the wind turbine, and divide the wind speed range into a preset number of wind speed intervals; The turbulence intensity parameters and wave parameters are calibrated based on the real ocean environment under different ocean environment conditions, and the wind field parameters of each wind speed range are determined based on the wave parameters and the wind speed parameters determined by the turbulence intensity parameters; Generate wind field files based on wind field parameters and wind turbine model parameters in each wind speed range; Dynamic simulation and load calculation are performed according to the wind field file and environmental parameters to obtain load information of the wind turbine blades.

3. The method according to claim 2, characterized in that Dynamic simulation and load calculation are performed according to the wind field file and environmental parameters to obtain load information of the wind turbine blades, including: Simulating the overall operation response of the wind turbine based on the wind farm file and environmental parameters to obtain simulation results; Determine the load distribution and time history of the fan blade based on the blade element momentum theory, the beam model and the simulation results; The load distribution and time history are converted into equivalent cyclic loads to obtain load information of the fan blades.

4. The method according to claim 2, characterized in that: According to the fatigue damage distribution diagram in the simulation results, the fatigue hotspot areas of the blade throughout its life cycle are determined, and the crack arrangement of the finite element model is performed based on the fatigue hotspot areas, including: Finite element software is used to obtain fatigue damage distribution maps in simulation results under different marine environment conditions, and to determine fatigue hotspots throughout the life cycle of the blade; Crack placement of the finite element model in the fatigue hotspot area.

5. The method according to claim 4, characterized in that The finite element model includes a plurality of units, and the cracks are arranged using the following process: At the intersection of elements, a new node with the same geometric position as the original node is generated; The elements adjacent to the new node are redefined using the new node to generate cracks.

6. The method according to claim 1, characterized in that Analysis of crack growth in wind turbine blades based on new simulation results, including: Analyzing the blade fracture parameters according to the new simulation results to obtain a first analysis result, wherein the blade fracture parameters include a stress intensity factor; Analyze the crack propagation behavior of the blade based on the first analysis result to obtain a second analysis result; A simulation analysis of blade crack propagation is performed based on the first analysis result and the second analysis result.

7. The method according to claim 6, characterized in that The stress intensity factor is determined based on the strain energy release rate and elastic modulus under different wind speed intervals; the second analysis result includes the crack growth rate and the stress intensity range; Performing a simulation analysis on the blade crack propagation based on the first analysis result and the second analysis result includes: Arrange spring units with variable stiffness between adjacent units at the crack tip according to a preset crack propagation path; Based on the stress intensity factor, crack growth rate and stress intensity range, the stiffness of the spring unit is adjusted to perform multiple cycles of simulation to obtain the crack growth analysis results on the finite element model.

8. A crack propagation analysis device for wind turbine blades taking into account the real marine environment, characterized in that: The device comprises: A load distribution determination module is used to perform dynamic simulation on wind turbine blades based on real marine environmental parameters under different marine environmental conditions to determine the load distribution information borne by the wind turbine blades; A loading simulation module is used to load the load distribution information into a finite element model of the blade, simulate the fatigue damage process of the blade, and obtain a simulation result; The crack arrangement module is used to determine the fatigue hotspot areas of the blade throughout its life cycle according to the fatigue damage distribution map in the simulation results, and to arrange cracks in the finite element model based on the fatigue hotspot areas; The new working condition simulation module is used to reset the typical working condition as the new working condition for wind turbine simulation and load calculation, load the load distribution information of the new working condition to the finite element model with cracks, re-simulate the blade fatigue damage process, and obtain new simulation results; An extended analysis module for crack growth analysis of wind turbine blades based on new simulation results.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the crack propagation analysis method for wind turbine blades taking into account the real marine environment as described in any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the crack propagation analysis method for a wind turbine blade taking into account the real marine environment according to any one of claims 1 to 7.

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