A calculation method for fatigue damage of jacket based on multi-scale model

Abstract

The embodiment of the present invention provides a method for calculating fatigue damage of a jacket based on a multi-scale model, the method comprising obtaining a multi-scale finite element model of the jacket; determining key components in the jacket, selecting nodes where multiple key components intersect as analysis nodes, and determining vulnerable parts of the analysis nodes; loading wind, wave and current loads into the multi-scale finite element model, performing time history analysis on vulnerable parts and using the rain flow counting method to perform statistics on stress time history, obtaining variable stress amplitudes and average stresses at various levels, determining the equivalent constant stress amplitudes corresponding to variable stress amplitudes at various levels, and determining the fatigue damage increment of vulnerable parts within the load history based on the Lemaitre high-cycle fatigue damage evolution theory. The embodiment of the present invention calculates the fatigue damage generated by vulnerable parts within the load history through the Lemaitre high-cycle fatigue damage model, which can accurately describe the influence of micro-defect evolution and truly reflect the nonlinear accumulation process of fatigue damage of the jacket.

Description

Technical Field

[0001] The invention relates to the field of marine engineering and simulation technology, and in particular to a method for calculating fatigue damage of a jacket based on a multi-scale model. Background Art

[0002] As a key marine engineering structure, fixed jackets are widely used in offshore wind farms, oil drilling platforms and submarine resource development facilities. Its complex spatial truss structure formed by intersecting and welding steel pipes not only provides a stable foundation support, but also can effectively resist various forces in harsh marine environments, such as wind, waves, currents and earthquakes. However, in actual operation, the jacket will be subjected to multiple types of fatigue loads at the same time. The complexity and uncertainty of these loads pose a challenge to the long-term safety of the structure.

[0003] In order to accurately evaluate the structural health status of the jacket under multiple fatigue loads, the time history analysis method is usually used in engineering practice for overall coupled fatigue analysis. After the response time history data is statistically analyzed, it is substituted into the fatigue damage model. The fatigue damage model used in the study is mainly based on Miner theory, which regards the accumulation process of damage as linearly superimposable and does not consider the loading order of the loads, making the results more conservative, thus affecting the accurate judgment of the structural health status. Summary of the invention

[0004] In view of the above problems, embodiments of the present invention are proposed to provide a method for calculating fatigue damage of a jacket based on a multi-scale model and a corresponding device for calculating fatigue damage of a jacket based on a multi-scale model, which overcome the above problems or at least partially solve the above problems.

[0005] According to a first aspect of an embodiment of the present invention, a method for calculating fatigue damage of a jacket based on a multi-scale model is provided, the method comprising:

[0006] Acquire a multi-scale finite element model of a catheter frame; the catheter frame includes a plurality of components;

[0007] Determine key components in the jacket, select nodes where multiple key components intersect as analysis nodes, and determine vulnerable locations of the analysis nodes;

[0008] Simulate wind, wave and current loads;

[0009] Loading the wind, wave and current loads to the multi-scale finite element model, and performing a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history;

[0010] The stress time history of the vulnerable part of the analysis node is statistically analyzed by using the rain flow counting method to obtain the variable stress amplitudes of each level and the corresponding average stress, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes of each level;

[0011] According to the variable stress amplitudes at each level, the average stress and the equivalent constant stress amplitude, based on Lemaitre high cycle fatigue damage evolution theory, the fatigue damage increment of the vulnerable part of the analysis node within the load history is determined.

[0012] Optionally, the step of determining the fatigue damage increment of the vulnerable part of the analysis node within the load history according to the variable stress amplitudes, the average stress and the equivalent constant stress amplitude at each level and based on Lemaitre's high cycle fatigue damage evolution theory includes:

[0013] According to the variable stress amplitudes, average stress and equivalent constant stress amplitudes at each level, based on Lemaitre high cycle fatigue damage evolution theory, the fatigue damage increment of the vulnerable part of the analysis node in the load history is determined according to the following formula ;

[0014] The formula is:

[0015]

[0016]

[0017] is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , is the coefficient, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

[0018] Optionally, the simulated wind, wave and current loads include:

[0019] The wind load acting on the top blade and the hub connected to the jacket is simulated, the wind load acting on the tower connected to the jacket is simulated, and the wave load acting on the jacket is simulated.

[0020] Optionally, the simulating wind load acting on the top blades and the hub connected to the jacket includes:

[0021] The wind load acting on the top blade and the hub connected to the jacket is simulated according to the following formula:

[0022]

[0023] in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed;

[0024] The simulation of the wind load acting on the tower connected to the jacket includes:

[0025] According to the following formula, the wind load acting on the tower connected to the jacket is simulated;

[0026]

[0027] in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

[0028] Optionally, the simulating wave load acting on the jacket includes:

[0029] The wave load acting on the jacket is simulated according to the following formula;

[0030]

[0031]

[0032]

[0033] Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height;

[0034] Said Determined by the following formula:

[0035]

[0036] Where: is the wave surface elevation; is the PM wave energy spectral density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

[0037] Optionally, the step of obtaining a multi-scale finite element model of the jacket includes:

[0038] Acquire position information and size information of multiple components included in the jacket, and establish a macroscopic bar system model of the jacket according to the position information and size information of the multiple components;

[0039] Acquiring dimension information of the intersecting nodes in the conductor rack, and establishing a mesoscopic model of the intersecting nodes in the conductor rack according to the dimension information of the intersecting nodes;

[0040] The microscopic model of the intersecting node is embedded in the macroscopic bar system model to obtain a multi-scale finite element model of the conductor frame.

[0041] Optionally, the determining of key components in the conductor rack includes:

[0042] According to a preset load, stress tests are performed on multiple components in the multi-scale finite element model to obtain stress responses;

[0043] For each component, performing a fragility analysis on the component according to the stress response corresponding to the preset load;

[0044] According to the vulnerability analysis results of the various components, key components are determined.

[0045] According to a second aspect of the present invention, there is provided a catheter fatigue damage calculation device based on a multi-scale model, the device comprising:

[0046] A model acquisition module is used to acquire a multi-scale finite element model of a catheter rack; the catheter rack includes a plurality of components;

[0047] A component determination module is used to determine key components in the jacket, select nodes where multiple key components intersect as analysis nodes, and determine vulnerable parts of the analysis nodes;

[0048] Load simulation module, used to simulate wind, wave and current loads;

[0049] A load loading module, used for loading the wind wave current load into the multi-scale finite element model, and performing a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history;

[0050] A time history statistics module is used to use a rain flow counting method to perform statistics on the stress time history of the vulnerable part of the analysis node, obtain variable stress amplitudes at various levels and corresponding average stresses, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes at various levels;

[0051] The increment determination module is used to determine the fatigue damage increment of the vulnerable part of the analysis node within the load history based on the variable stress amplitudes of each level, the average stress and the equivalent constant stress amplitude and based on the Lemaitre high cycle fatigue damage evolution theory.

[0052] Optionally, the increment determination module includes:

[0053] The increment determination submodule is used to determine the fatigue damage increment of the vulnerable part of the analysis node in the load history according to the variable stress amplitude, average stress and equivalent constant stress amplitude of each level, based on Lemaitre high cycle fatigue damage evolution theory, according to the following formula ;

[0054] The formula is:

[0055]

[0056]

[0057] is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , is the coefficient, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

[0058] Optionally, the load simulation module includes:

[0059] The load simulation submodule is used to simulate the wind load acting on the top blades and the hub connected to the conductor frame, simulate the wind load acting on the tower connected to the conductor frame, and simulate the wave load acting on the conductor frame.

[0060] Optionally, the load simulation submodule includes:

[0061] The first load simulation unit is used to simulate the wind load acting on the top blade and the hub connected to the jacket according to the following formula:

[0062]

[0063] in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed;

[0064] The simulation of the wind load acting on the tower connected to the jacket includes:

[0065] According to the following formula, the wind load acting on the tower connected to the jacket is simulated;

[0066]

[0067] in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

[0068] Optionally, the load simulation submodule includes:

[0069] A second load simulation unit is used to simulate the wave load acting on the jacket according to the following formula;

[0070]

[0071]

[0072]

[0073] Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height;

[0074] Said Determined by the following formula:

[0075]

[0076] Where: is the wave surface elevation; is the PM wave energy spectral density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

[0077] Optionally, the model acquisition module includes:

[0078] The first model acquisition submodule is used to acquire position information and size information of multiple components included in the jacket, and establish a macroscopic bar system model of the jacket according to the position information and size information of the multiple components;

[0079] A second model acquisition submodule is used to acquire the size information of the intersecting nodes in the jacket and establish a mesoscopic model of the intersecting nodes in the jacket according to the size information of the intersecting nodes;

[0080] The third model acquisition submodule is used to embed the microscopic model of the intersecting node into the macroscopic bar system model to obtain a multi-scale finite element model of the jacket.

[0081] Optionally, the component determination module includes:

[0082] A first component determination submodule is used to perform stress tests on multiple components in the multi-scale finite element model according to a preset load to obtain stress responses;

[0083] A second component determination submodule is used to perform a vulnerability analysis on each component according to the stress response corresponding to the preset load;

[0084] The third component determination submodule is used to determine the key components according to the vulnerability analysis results of the various components.

[0085] According to a third aspect of the present invention, there is provided an electronic device, the electronic device comprising:

[0086] A processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the method for calculating fatigue damage of a jacket based on a multi-scale model as described in any one of the above items.

[0087] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the method for calculating fatigue damage of a jacket based on a multi-scale model as described in any one of the above items is implemented.

[0088] The technical solution provided by the embodiments of the present invention may have the following beneficial effects:

[0089] The embodiment of the present invention discloses a method for calculating fatigue damage of a jacket based on a multi-scale model, the method comprising obtaining a multi-scale finite element model of the jacket; determining key components in the jacket, selecting nodes where multiple key components intersect as analysis nodes, and determining vulnerable parts of the analysis nodes; loading wind, wave and current loads into the multi-scale finite element model, performing time history analysis on vulnerable parts and using the rain flow counting method to perform statistics on stress time history, obtaining variable stress amplitudes and average stresses at various levels, determining the equivalent constant stress amplitudes corresponding to variable stress amplitudes at various levels, and determining the fatigue damage increment of vulnerable parts within the load history based on the Lemaitre high-cycle fatigue damage evolution theory. The embodiment of the present invention calculates the fatigue damage generated by vulnerable parts within the load history through the Lemaitre high-cycle fatigue damage model, which can accurately describe the impact of micro-defect evolution on component performance degradation, and can truly reflect the nonlinear accumulation process of fatigue damage of the jacket. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Figure 1 It is a flowchart of the steps of a method for calculating fatigue damage of a jacket based on a multi-scale model provided by an embodiment of the present invention;

[0091] Figure 2 is a structural schematic diagram of a conductor pipe frame provided by an embodiment of the present invention;

[0092] Figure 3 It is a structural block diagram of a method and device for calculating fatigue damage of a jacket based on a multi-scale model provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0093] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0094] As a key marine engineering structure, fixed jackets are widely used in offshore wind farms, oil drilling platforms and submarine resource development facilities. Its complex spatial truss structure formed by intersecting and welding steel pipes not only provides a stable foundation support, but also can effectively resist various forces in harsh marine environments, such as wind, waves, currents and earthquakes. However, in actual operation, the jacket will be subjected to multiple types of fatigue loads at the same time. The complexity and uncertainty of these loads pose a challenge to the long-term safety of the structure.

[0095] In order to accurately evaluate the structural health status of the jacket under multiple fatigue loads, the time history analysis method is usually used in engineering practice for overall coupled fatigue analysis. After the response time history data is statistically analyzed, it is substituted into the fatigue damage model. The fatigue damage model used in the study is mainly based on Miner theory, which regards the accumulation process of damage as linearly superimposable and does not consider the loading order of the loads, making the results more conservative, thus affecting the accurate judgment of the structural health status.

[0096] The embodiment of the present invention calculates the fatigue damage generated in the vulnerable part during the load history through the Lemaitre high cycle fatigue damage model, which can accurately describe the impact of micro-defect evolution on component performance degradation and truly reflect the nonlinear accumulation process of fatigue damage of the jacket.

[0097] Reference Figure 1 , shows a flowchart of a method for calculating fatigue damage of a jacket based on a multi-scale model provided by an embodiment of the present invention, wherein the method may specifically include the following steps:

[0098] Step 101, obtaining a multi-scale finite element model of a catheter rack; the catheter rack includes a plurality of components;

[0099] Reference Figure 2 , showing a schematic structural diagram of a conductor frame including multiple components.

[0100] Multiscale finite element model is a numerical simulation method used to solve complex engineering problems. It combines physical phenomena at different scales to more accurately describe and predict the performance of materials and the behavior of structures. Multiscale finite element model can be obtained by combining macroscopic model and microscopic model. In one example, the multiscale finite element model of the jacket can be obtained by combining the macroscopic bar system model of the jacket and the microscopic model of the intersecting nodes in the jacket. The jacket structure is composed of many intersecting circular tubes of different sizes, and the internal forces on the components are mainly axial forces.

[0101] In one embodiment, step 101 may include the following sub-steps:

[0102] Sub-step S11, obtaining position information and size information of multiple components included in the jacket, and establishing a macroscopic bar system model of the jacket according to the position information and size information of the multiple components;

[0103] By carefully collecting the location and size information of each component, the accuracy of the model can be ensured and design errors caused by missing information can be avoided. The establishment of a macroscopic bar system model is based on these precise data, simplifying the complex three-dimensional solid structure into a series of interconnected bars, which can not only greatly reduce the calculation complexity, but also more intuitively analyze the mechanical behavior of the jacket under different load conditions.

[0104] The macroscopic bar system model represents the overall size of the jacket and can be used to calculate stress distribution at a macroscopic scale.

[0105] Sub-step S12, obtaining size information of the intersecting nodes in the jacket, and establishing a mesoscopic model of the intersecting nodes in the jacket according to the size information of the intersecting nodes;

[0106] The mesoscopic model reflects the mesoscopic structure of the intersecting node, and more detailed analysis can be performed at the mesoscopic scale. Specifically, after obtaining the dimensional information of the intersecting node in the jacket, by measuring the diameter, wall thickness, intersection angle and other parameters of each component, using CAD or professional modeling software to input these data, a three-dimensional model of the node is constructed to achieve accurate simulation of the mesoscopic structure of the jacket intersecting node.

[0107] An intersecting node is a node where two or more components intersect and connect together in space. These components can be beams, columns, truss members, etc., which are fixed together at the node by welding, bolting, riveting or other connection methods. It can be understood that an intersecting node is a point where components intersect. The conductor rack node belongs to an intersecting node, and its construction form is: the main rods remain connected, and the support rods are connected to the main rods by welding. Compared with the main rods that can withstand large bending moments, the support rods have weaker bending stiffness due to their large slenderness ratio, so the support rods are subjected to smaller bending moments at the nodes.

[0108] As the intersection of various components in the conductor frame, the intersection node is subjected to load transfer and force concentration effects from multiple directions. The rationality of its design is directly related to the stability and durability of the entire structure. In addition, the geometry of the intersection node is complex and the stress concentration phenomenon is significant. The traditional macroscopic model may not be able to accurately describe the detailed stress distribution in this tiny area. Through the mesoscopic model, the geometric details of the node, the characteristics of the contact surface, and the welding quality can be carefully considered, which is crucial for evaluating the strength and fatigue life of the node.

[0109] Sub-step S13, embedding the microscopic model of the intersecting node into the macroscopic bar system model to obtain a multi-scale finite element model of the jacket.

[0110] Although the macro model can effectively evaluate the stability and response of the structure as a whole, its simplified processing may lead to a decrease in analysis accuracy for complex geometries and high stress concentration areas such as intersecting nodes. The meso model focuses on details and can simulate welds, contact surfaces and material micro-properties in detail to ensure more accurate reliability assessment of key nodes. The meso model of the intersecting node is embedded in the macro bar system model to form a cross-scale finite element model, which can accurately capture the complex mechanical behavior of key parts while maintaining the overall analysis efficiency of the structure. Specifically, the meso model of the intersecting node is embedded in the macro bar system model, first ensuring the geometric alignment between the meso model and the macro model. Then, the key nodes of the meso model can be associated with the nodes at the corresponding positions of the macro model through multi-point constraints to ensure coordinated deformation between the two. In this way, the construction of the multi-scale finite element model of the conductor frame can be completed.

[0111] Step 102, determining key components in the jacket, selecting nodes where multiple key components intersect as analysis nodes, and determining vulnerable locations of the analysis nodes;

[0112] Based on structural function analysis and force analysis, components that carry critical loads are identified. Then, the nodes where these components meet are selected as analysis nodes, and the vulnerable parts in the nodes are determined by carefully checking the node structure and force conditions. Determining the key components in the jacket and selecting the nodes where multiple key components meet as analysis nodes is based on a basic principle in structural engineering: the safety and stability of a structure often depends on its weakest link. In complex marine engineering structures such as jackets, key components bear the main load transfer tasks, and their performance directly affects the stability and service life of the entire structure. Especially at the nodes where components meet, due to stress concentration and complex load distribution, fatigue cracks are more likely to initiate and develop, becoming vulnerable parts in the structure.

[0113] Selecting these nodes for detailed analysis can more accurately assess the fatigue damage state of the structure and promptly identify potential safety hazards. By monitoring and evaluating vulnerable parts, engineers can develop targeted maintenance plans and take necessary reinforcement measures to extend the service life of the structure and reduce the occurrence of accidents. In addition, this targeted analysis method also improves engineering efficiency, avoids the high cost and time consumption of a comprehensive inspection of the entire structure, and achieves effective use of resources.

[0114] In one embodiment, step 102 may include the following sub-steps:

[0115] Sub-step S21, performing stress tests on multiple components in the multi-scale finite element model according to a preset load to obtain stress responses;

[0116] In an embodiment of the present invention, a preset load can be applied to a multi-scale finite element model for stress testing, wherein the preset load can be a load combination. This is usually done using structural analysis software, such as MIDAS, ANSYS, SAP2000, etc. Taking the general process as an example, the specific operations may vary depending on the software: (1) Define load conditions; (2) Input load information; (3) Define load combinations; (4) Perform structural analysis; (5) View and interpret stress results: After the analysis is completed, the stress response under each load combination can be viewed in the software. You may need to select a specific combination of stress results in the result menu and use the graphical interface provided by the software, such as cloud maps, charts, or lists, to view the stress distribution. For bar system models, focus on node stress, bar axial stress, normal stress and shear stress caused by bending moment, etc.; (6) Output and record the results;

[0117] Sub-step S22, for each component, performing a vulnerability analysis on the component according to the stress response corresponding to the preset load;

[0118] Specifically, for each component, the vulnerability analysis is performed according to the stress response corresponding to the preset load according to the following formula; the formula is:

[0119]

[0120]

[0121] is the vulnerability index of the i-th component; is the response of the i-th component under adverse conditions; For all The maximum value in ; is the stress response of the i-th component; is the preset load corresponding to the i-th component.

[0122] Sub-step S23, determining key components according to the vulnerability analysis results of the various components.

[0123] Calculated vulnerability index of each component , components are sorted according to their vulnerability index, and components with higher vulnerability index or greater than the threshold are selected as key components.

[0124] Step 103, simulating wind wave and current loads;

[0125] Simulating wind, wave and current loads is crucial for the safety assessment and design of offshore structures, because these natural forces are unpredictable and will produce complex and continuous dynamic pressure on the structure, accelerate material fatigue and increase the risk of structural damage. Through simulation, engineers can predict the response of the structure under extreme conditions, ensure its stability and safety, optimize the design, achieve a balance between economy and efficiency, provide data support for maintenance strategies, and effectively extend the service life of the structure.

[0126] In one embodiment, step 103 may include the following sub-steps:

[0127] Sub-step S31 is to simulate the wind load acting on the top blades and the hub connected to the jacket, simulate the wind load acting on the tower connected to the jacket, and simulate the wave load acting on the jacket.

[0128] Wind load refers to the force generated by wind acting on the surface of a structure. As key components of wind turbines, the wind loads borne by blades and hubs directly affect the stable operation and energy conversion efficiency of the system; as a supporting structure, the simulation of wind loads on the tower helps to evaluate the dynamic response and fatigue life of the structure. At the same time, considering that the jacket works in a marine environment, the simulation of wave loads is to accurately grasp the stress conditions of the jacket under complex sea conditions and prevent potential structural damage and system failures.

[0129] In one embodiment, the sub-step S31 may further include:

[0130] Sub-step S311, simulating the wind load acting on the top blades and the hub connected to the jacket according to the following formula:

[0131]

[0132] in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed;

[0133] The simulation of the wind load acting on the tower connected to the jacket includes:

[0134] According to the following formula, the wind load acting on the tower connected to the jacket is simulated;

[0135]

[0136] in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

[0137] Sub-step S312, simulating the wave load acting on the jacket according to the following formula;

[0138]

[0139]

[0140]

[0141] Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height;

[0142] Said Determined by the following formula:

[0143]

[0144] Where: is the wave surface elevation; is the PM wave energy spectral density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

[0145] Step 104, loading the wind wave current load into the multi-scale finite element model, and performing a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history;

[0146] Stress time history refers to the stress history of a certain point or area of ​​a structure under dynamic loads. In engineering and structural analysis, stress time history data is usually obtained through finite element analysis (FEA), vibration analysis, impact analysis or wind tunnel experiments, which can describe in detail the changes in stress levels of the structure under transient or periodic loads over time.

[0147] Loading wind, wave and current loads to multi-scale finite element models and performing time-history analysis on vulnerable parts of analysis nodes to determine stress time history are key steps in ensuring the safety and reliability of offshore structures such as jackets. This process is critical because the natural environment faced by offshore structures is extremely harsh and changeable. Wind, waves and ocean currents are not only strong, but also change direction and frequency with time and location, forming complex dynamic loads. These loads produce continuous mechanical stress on the structure, especially at the nodes where key components meet, where stress concentration is significant and is a high-risk area prone to fatigue cracks and structural damage.

[0148] By loading wind, wave and current loads into a multi-scale finite element model, engineers can simulate the response of the structure in the actual environment and capture the subtle changes in stress distribution at every moment, thereby obtaining detailed stress time history data. This data is key information for evaluating the fatigue life and safety margin of the structure. Time history analysis can reveal the stress change trends and peak values ​​of vulnerable parts under complex loads, help identify potential structural weaknesses, and estimate the damage accumulation and remaining life of the structure. In addition, time history analysis can also provide a basis for the optimal design of the structure. By adjusting material properties, structural layout or adding reinforcements, engineers can take measures in the design stage to enhance the structure's resistance to harsh environments, reduce maintenance costs, and extend the service life of the structure.

[0149] Step 105, using a rain flow counting method to perform statistics on the stress time history of the vulnerable part of the analysis node, obtain variable stress amplitudes of various levels and corresponding average stresses, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes of various levels;

[0150] Half of the range of stress fluctuations experienced by a material or structure under alternating loads. Under dynamic or cyclic loads, the stress on a material or structure is not constant but varies with time, and this stress usually shows periodic fluctuations. The variable stress amplitude is an important parameter to measure this fluctuation amplitude, which is equal to half of the difference between the maximum stress and the minimum stress.

[0151] Stress time history data contains the dynamic characteristics of structural response and reflects detailed information on the time-varying stress inside the structure under complex environmental loads such as wind, waves, and currents. These data not only include the peak value of instantaneous stress, but more importantly, they show the fluctuation pattern of stress over time, which is the key to evaluating structural fatigue damage. Through statistical analysis, the continuous stress time history can be converted into a series of discrete stress cycles, each cycle consisting of a variable stress amplitude and an average stress. The variable stress amplitude reflects the range of stress fluctuations, while the average stress reflects the bias level of the cyclic stress. These parameters are the basic inputs in fatigue analysis and are used to evaluate the fatigue life of materials under alternating loads.

[0152] The stress history can be statistically analyzed using the rainflow counting method. The rainflow counting method is a method used to evaluate the fatigue life of structures. It simplifies complex stress history to estimate the degree of fatigue damage of materials or structures. The rainflow counting method is characterized by its dual parameter basis, which takes into account both dynamic strength (stress amplitude) and static strength (mean stress). Through specific steps such as filtering out small amplitudes, peak and valley filtering, and discretization, a series of standard cycles are finally formed. Through statistical analysis, the continuous stress history can be converted into a series of discrete stress cycles, each consisting of a variable stress amplitude and a mean stress. The variable stress amplitude reflects the range of stress fluctuations, while the mean stress reflects the bias level of the cyclic stress. These parameters are the basic inputs in fatigue analysis and are used to evaluate the fatigue life of materials under alternating loads.

[0153] Next, the equivalent constant stress amplitude corresponding to each level of variable stress amplitude is determined, which is to convert the variable stress cycle into an equivalent constant stress cycle. This conversion is based on the fatigue damage equivalence principle, that is, the same fatigue damage caused by different stress cycles can be represented by an equivalent constant stress cycle. This conversion simplifies the subsequent fatigue damage assessment and enables engineers to use the standard stress-life curve to perform damage accumulation calculations and thus predict the remaining life of the structure.

[0154] Step 106, determining the fatigue damage increment of the vulnerable part of the analysis node within the load history according to the variable stress amplitudes of each level, the average stress and the equivalent constant stress amplitude based on Lemaitre high cycle fatigue damage evolution theory.

[0155] Lemaitre's high-cycle fatigue damage evolution theory is a micromechanical model used to describe and predict the damage accumulation of metal materials under high-cycle fatigue conditions. Under high-cycle fatigue conditions, the stress level to which the material is subjected is usually far below its yield strength, but after tens of thousands or even millions of stress cycles, the material will still be damaged and eventually fail. Lemaitre's theory believes that this damage is caused by microscopic plastic deformation caused by the movement and accumulation of dislocations within the material. As the stress cycle proceeds, the dislocation density increases, causing changes in the material's microstructure, forming damage nuclei, and eventually developing into macroscopic cracks.

[0156] According to the variable stress amplitude, average stress and equivalent constant stress amplitude at each level, the fatigue damage increment of the vulnerable parts of the analysis node is determined based on the Lemaitre high-cycle fatigue damage evolution theory in order to accurately evaluate the damage accumulation process of the structure under complex loads. This process quantifies the damage caused to the material microstructure by each stress cycle, taking into account the effects of plastic deformation, stress state and load sequence on fatigue behavior, thus surpassing the limitations of the traditional linear damage accumulation model. The Lemaitre theory can more realistically reflect the nonlinear accumulation of damage, especially under multi-axial stress states. It can effectively predict the formation and expansion of damage nuclei, providing a scientific basis for predicting the remaining life of the structure, optimizing the design and maintenance strategies, and ensuring the safety and economy of offshore engineering structures such as jackets in harsh environments.

[0157] In one embodiment, step 106 may include the following sub-steps:

[0158] Sub-step S61, according to the variable stress amplitudes, average stress and equivalent constant stress amplitudes at each level, based on Lemaitre high cycle fatigue damage evolution theory, the fatigue damage increment of the vulnerable part of the analysis node in the load history is determined according to the following formula: ;

[0159] The formula is:

[0160]

[0161]

[0162] is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , The coefficient can be customized, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

[0163] The embodiment of the present invention discloses a method for calculating fatigue damage of a jacket based on a multi-scale model, the method comprising obtaining a multi-scale finite element model of the jacket; determining key components in the jacket, selecting nodes where multiple key components intersect as analysis nodes, and determining vulnerable parts of the analysis nodes; loading wind, wave and current loads into the multi-scale finite element model, performing time history analysis on vulnerable parts and using the rain flow counting method to perform statistics on stress time history, obtaining variable stress amplitudes and average stresses at various levels, determining the equivalent constant stress amplitudes corresponding to variable stress amplitudes at various levels, and determining the fatigue damage increment of vulnerable parts within the load history based on the Lemaitre high-cycle fatigue damage evolution theory. The embodiment of the present invention calculates the fatigue damage generated by vulnerable parts within the load history through the Lemaitre high-cycle fatigue damage model, which can accurately describe the impact of micro-defect evolution on component performance degradation, and can truly reflect the nonlinear accumulation process of fatigue damage of the jacket.

[0164] It should be noted that, for the sake of simplicity, the method embodiments are described as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0165] Reference Figure 3 , shows a structural block diagram of a catheter fatigue damage calculation device based on a multi-scale model provided by an embodiment of the present invention, which may specifically include the following modules:

[0166] The model acquisition module 301 is used to acquire a multi-scale finite element model of a conductor frame; the conductor frame includes a plurality of components;

[0167] A component determination module 302 is used to determine key components in the jacket, select nodes where multiple key components intersect as analysis nodes, and determine vulnerable locations of the analysis nodes;

[0168] The load simulation module 303 is used to simulate wind wave and current loads;

[0169] A load loading module 304 is used to load the wind wave current load to the multi-scale finite element model, and perform a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history;

[0170] The time history statistics module 305 is used to use the rain flow counting method to perform statistics on the stress time history of the vulnerable part of the analysis node, obtain the variable stress amplitudes of each level and the corresponding average stress, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes of each level;

[0171] The increment determination module 306 is used to determine the fatigue damage increment of the vulnerable part of the analysis node within the load history based on the variable stress amplitudes of each level, the average stress and the equivalent constant stress amplitude and based on the Lemaitre high cycle fatigue damage evolution theory.

[0172] In one embodiment, the increment determination module includes:

[0173] The increment determination submodule is used to determine the fatigue damage increment of the vulnerable part of the analysis node in the load history according to the variable stress amplitude, average stress and equivalent constant stress amplitude of each level, based on Lemaitre high cycle fatigue damage evolution theory, according to the following formula ;

[0174] The formula is:

[0175]

[0176]

[0177] is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , is the coefficient, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

[0178] In one embodiment, the load simulation module includes:

[0179] The load simulation submodule is used to simulate the wind load acting on the top blades and the hub connected to the conductor frame, simulate the wind load acting on the tower connected to the conductor frame, and simulate the wave load acting on the conductor frame.

[0180] In one embodiment, the load simulation submodule includes:

[0181] The first load simulation unit is used to simulate the wind load acting on the top blade and the hub connected to the jacket according to the following formula:

[0182]

[0183] in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed;

[0184] The simulation of the wind load acting on the tower connected to the jacket includes:

[0185] According to the following formula, the wind load acting on the tower connected to the jacket is simulated;

[0186]

[0187] in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

[0188] In one embodiment, the load simulation submodule includes:

[0189] A second load simulation unit is used to simulate the wave load acting on the jacket according to the following formula;

[0190]

[0191]

[0192]

[0193] Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height;

[0194] Said Determined by the following formula:

[0195]

[0196] Where: is the wave surface elevation; is the PM wave energy spectrum density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

[0197] In one embodiment, the model acquisition module includes:

[0198] The first model acquisition submodule is used to acquire position information and size information of multiple components included in the jacket, and establish a macroscopic bar system model of the jacket according to the position information and size information of the multiple components;

[0199] A second model acquisition submodule is used to acquire the size information of the intersecting nodes in the jacket and establish a mesoscopic model of the intersecting nodes in the jacket according to the size information of the intersecting nodes;

[0200] The third model acquisition submodule is used to embed the microscopic model of the intersecting node into the macroscopic bar system model to obtain a multi-scale finite element model of the jacket.

[0201] In one embodiment, the component determination module includes:

[0202] A first component determination submodule is used to perform stress tests on multiple components in the multi-scale finite element model according to a preset load to obtain stress responses;

[0203] A second component determination submodule is used to perform a vulnerability analysis on each component according to the stress response corresponding to the preset load;

[0204] The third component determination submodule is used to determine the key components according to the vulnerability analysis results of the various components.

[0205] The embodiment of the present invention discloses a method for calculating fatigue damage of a jacket based on a multi-scale model, the method comprising obtaining a multi-scale finite element model of the jacket; determining key components in the jacket, selecting nodes where multiple key components intersect as analysis nodes, and determining vulnerable parts of the analysis nodes; loading wind, wave and current loads into the multi-scale finite element model, performing time history analysis on vulnerable parts and using the rain flow counting method to perform statistics on stress time history, obtaining variable stress amplitudes and average stresses at various levels, determining the equivalent constant stress amplitudes corresponding to variable stress amplitudes at various levels, and determining the fatigue damage increment of vulnerable parts within the load history based on the Lemaitre high-cycle fatigue damage evolution theory. The embodiment of the present invention calculates the fatigue damage generated by vulnerable parts within the load history through the Lemaitre high-cycle fatigue damage model, which can accurately describe the impact of micro-defect evolution on component performance degradation, and can truly reflect the nonlinear accumulation process of fatigue damage of the jacket.

[0206] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0207] An embodiment of the present invention further provides an electronic device, including:

[0208] The invention comprises a processor, a memory and a computer program stored in the memory and capable of running on the processor. When the computer program is executed by the processor, each process of the embodiment of the method for calculating fatigue damage of a jacket based on a multi-scale model is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0209] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, each process of the embodiment of the method for calculating fatigue damage of a jacket based on a multi-scale model is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be described here.

[0210] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0211] It will be appreciated by those skilled in the art that the embodiments of the present invention may be provided as methods, devices, or computer program products. Therefore, the embodiments of the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the embodiments of the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0212] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0213] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0214] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0215] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0216] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0217] The above is a detailed introduction to a method for calculating fatigue damage of a jacket based on a multi-scale model and a device for calculating fatigue damage of a jacket based on a multi-scale model provided by the present invention. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for calculating fatigue damage of a jacket based on a multi-scale model, characterized in that: include: Acquire a multi-scale finite element model of a catheter frame; the catheter frame includes a plurality of components; Determine key components in the jacket, select nodes where multiple key components intersect as analysis nodes, and determine vulnerable locations of the analysis nodes; Simulate wind, wave and current loads; Loading the wind, wave and current loads to the multi-scale finite element model, and performing a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history; The stress time history of the vulnerable part of the analysis node is statistically analyzed by using the rain flow counting method to obtain the variable stress amplitudes of each level and the corresponding average stress, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes of each level; According to the variable stress amplitudes, average stress and equivalent constant stress amplitudes at each level, based on Lemaitre high cycle fatigue damage evolution theory, the fatigue damage increment of the vulnerable part of the analysis node in the load history is determined according to the following formula ; The formula is: is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , is the coefficient, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

2. The method according to claim 1, characterized in that The simulated wind, wave and current loads include: The wind load acting on the top blade and the hub connected to the jacket is simulated, the wind load acting on the tower connected to the jacket is simulated, and the wave load acting on the jacket is simulated.

3. The method according to claim 2, characterized in that The simulation of wind loads acting on the top blades and the hub connected to the jacket includes: The wind load acting on the top blade and the hub connected to the jacket is simulated according to the following formula: in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed; The simulation of the wind load acting on the tower connected to the jacket includes: According to the following formula, the wind load acting on the tower connected to the jacket is simulated; in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

4. The method according to claim 2, characterized in that: The simulation of the wave load acting on the jacket includes: The wave load acting on the jacket is simulated according to the following formula; Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height; Said Determined by the following formula: Where: is the wave surface elevation; is the PM wave energy spectrum density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

5. The method according to claim 1, characterized in that The step of obtaining a multi-scale finite element model of the jacket includes: Acquire position information and size information of multiple components included in the jacket, and establish a macroscopic bar system model of the jacket according to the position information and size information of the multiple components; Acquiring dimension information of the intersecting nodes in the conductor rack, and establishing a mesoscopic model of the intersecting nodes in the conductor rack according to the dimension information of the intersecting nodes; The microscopic model of the intersecting node is embedded in the macroscopic bar system model to obtain a multi-scale finite element model of the conductor frame.

6. The method according to claim 1, characterized in that The determining of key components in the conductor frame includes: According to a preset load, stress tests are performed on multiple components in the multi-scale finite element model to obtain stress responses; For each component, performing a fragility analysis on the component according to the stress response corresponding to the preset load; According to the vulnerability analysis results of the various components, key components are determined.

7. A catheter frame fatigue damage calculation device based on a multi-scale model, characterized in that: include: A model acquisition module is used to acquire a multi-scale finite element model of a catheter rack; the catheter rack includes a plurality of components; A component determination module is used to determine key components in the jacket, select nodes where multiple key components intersect as analysis nodes, and determine vulnerable parts of the analysis nodes; Load simulation module, used to simulate wind, wave and current loads; A load loading module, used for loading the wind wave current load into the multi-scale finite element model, and performing a time history analysis on the vulnerable parts of the analysis nodes to determine the stress time history; A time history statistics module is used to use a rain flow counting method to perform statistics on the stress time history of the vulnerable part of the analysis node, obtain variable stress amplitudes at various levels and corresponding average stresses, and determine the equivalent constant stress amplitudes corresponding to the variable stress amplitudes at various levels; An increment determination module is used to determine the fatigue damage increment of the vulnerable part of the analysis node within the load history according to the variable stress amplitudes of each level, the average stress and the equivalent constant stress amplitude based on Lemaitre high cycle fatigue damage evolution theory; The increment determination module comprises: The increment determination submodule is used to determine the fatigue damage increment of the vulnerable part of the analysis node in the load history according to the variable stress amplitude, average stress and equivalent constant stress amplitude of each level, based on Lemaitre high cycle fatigue damage evolution theory, according to the following formula ; The formula is: is the variable stress amplitude at each level, is the average stress corresponding to each level of variable stress amplitude, The variable stress amplitude at each level effect The corresponding equivalent constant stress amplitude is: The variable stress amplitude at each level The total number of cycles, is the stress amplitude The number of cycles, B, , is the coefficient, D is the current damage value of the structure, is the damage increment of the structure during this period, is the total damage value of the structure, The total number of cycles in this process.

8. The device according to claim 7, characterized in that The load simulation module comprises: The load simulation submodule is used to simulate the wind load acting on the top blades and the hub connected to the conductor frame, simulate the wind load acting on the tower connected to the conductor frame, and simulate the wave load acting on the conductor frame.

9. The device according to claim 8, characterized in that The load simulation submodule includes: The first load simulation unit is used to simulate the wind load acting on the top blade and the hub connected to the jacket according to the following formula: in, is the wind load factor; is the air density; is the impeller swept area; is the instantaneous wind speed; The simulation of the wind load acting on the tower connected to the jacket includes: According to the following formula, the wind load acting on the tower connected to the jacket is simulated; in, is the tower shape coefficient; It is the projected area of ​​the tower on the plane perpendicular to the wind direction.

10. The device according to claim 8, characterized in that The load simulation submodule includes: A second load simulation unit is used to simulate the wave load acting on the jacket according to the following formula; Where: is the cylinder diameter; is the speed wind force; is the inertial wind force; for water depth; is the velocity force coefficient; is the inertia force coefficient; is the wave number; is the wave surface elevation; is the angular frequency; is the specific gravity of air; is the acceleration due to gravity; For time; is the tower height; Said Determined by the following formula: Where: is the wave surface elevation; is the PM wave energy spectrum density function; is the number of cosine waves superimposed; is the frequency spacing; is the average frequency; is the frequency; is the initial phase.

11. The device according to claim 7, characterized in that The model acquisition module includes: The first model acquisition submodule is used to acquire position information and size information of multiple components included in the jacket, and establish a macroscopic bar system model of the jacket according to the position information and size information of the multiple components; A second model acquisition submodule is used to acquire the size information of the intersecting nodes in the jacket and establish a mesoscopic model of the intersecting nodes in the jacket according to the size information of the intersecting nodes; The third model acquisition submodule is used to embed the microscopic model of the intersecting node into the macroscopic bar system model to obtain a multi-scale finite element model of the jacket.

12. The device according to claim 7, characterized in that The component determination module includes: A first component determination submodule is used to perform stress tests on multiple components in the multi-scale finite element model according to a preset load to obtain stress responses; A second component determination submodule is used to perform a vulnerability analysis on each component according to the stress response corresponding to the preset load; The third component determination submodule is used to determine the key components according to the vulnerability analysis results of the various components.

13. An electronic device, characterized in that: include: A processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the steps of the method for calculating fatigue damage of a jacket based on a multi-scale model as described in any one of claims 1 to 6 are implemented.

14. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for calculating fatigue damage of a jacket based on a multi-scale model according to any one of claims 1 to 6 are implemented.

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