Offshore wind turbine foundation scouring analysis reference surface elevation determination method and system

Abstract

The invention relates to a method and a system for determining the elevation of an offshore wind turbine foundation scouring analysis datum plane, and the method comprises the steps: carrying out three-dimensional modeling through seabed three-dimensional point cloud data, analyzing the thickness of shallow sludge through high-frequency and low-frequency sounding data, and obtaining stratum distribution through combining with shallow profile data; calculating a theoretical scouring depth based on the water flow data, and reconstructing a three-dimensional grid data model; calculating and screening a suitable area through a terrain gradient factor, and constructing a seabed base plane calculation data set; and calculating the average elevation of each fan basic area as the datum level elevation of scouring analysis. According to the method, refined reconstruction of the regional landform of the offshore wind turbine foundation is realized, the accuracy and scientificity of determining the elevation of the reference surface are improved, reliable data support is provided for stability evaluation and design optimization of the offshore wind turbine foundation, the structural safety risk caused by scouring is remarkably reduced, and the economic benefit is improved. And the overall safety and economic benefits of the offshore wind power plant are improved.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine generator sets, and mainly to a method and system for determining the elevation of a datum surface for scour analysis of an offshore wind turbine foundation. Background Art

[0002] As the global demand for renewable energy continues to increase, offshore wind power, as a form of clean energy, has received widespread attention and rapid development. However, the stability and safety of offshore wind turbines largely depend on the stability of their foundation structures, and seabed scouring is one of the important factors affecting the stability of wind turbine foundations. Seabed scouring can cause soil loss around the wind turbine foundation, thereby affecting the bearing capacity of the foundation and may even lead to serious consequences such as wind turbine overturning. Therefore, accurate analysis and monitoring of offshore wind turbine foundation scouring is crucial to ensure the safe operation of wind turbines.

[0003] In the existing offshore wind turbine foundation scour analysis methods, the elevation of the three-dimensional point cloud data of the seabed around the wind turbine foundation is usually directly used as the reference surface. The specific method is to take the average of the seabed elevation within a range of 50 meters × 50 meters as the reference surface elevation of the area. However, this method has some obvious shortcomings. First, since the average seabed elevation during each monitoring period may be inconsistent, the results of each scour analysis are relative and cannot be effectively compared with the previous analysis results. This inconsistency is particularly evident in areas with severe scour, which often leads to inconsistent reference surfaces, resulting in inconsistent scour analysis data and difficulty in accurately reflecting the actual scour situation.

[0004] In addition, the existing methods fail to fully consider the influence of factors such as submarine flow characteristics and terrain slope factors on the scouring process, which limits the scientificity and continuity of scouring analysis. Especially under complex submarine terrain and variable ocean current conditions, directly using the average elevation as the reference surface often cannot accurately reflect the actual scouring situation, which in turn affects the accuracy and reliability of scouring analysis.

[0005] Therefore, in order to solve the shortcomings of existing methods in offshore wind turbine foundation scour analysis, it is urgent to propose a method for determining the datum elevation. Summary of the invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a method and system for determining the elevation of a reference surface for scour analysis of an offshore wind turbine foundation.

[0007] The technical solution of the present invention is as follows:

[0008] In one aspect, the present invention provides a method for determining the elevation of a reference surface for scour analysis of an offshore wind turbine foundation, the method comprising:

[0009] Collect seabed 3D point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment;

[0010] Performing three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and performing grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model;

[0011] Calculating the thickness of shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data;

[0012] Obtaining stratum distribution data based on shallow profile data, including the depth and thickness of different strata, and determining the thickness of the sediment layer in each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing;

[0013] The theoretical scour depth of each wind turbine foundation area is calculated using a semi-analytical balanced scour formula based on water flow data;

[0014] The original three-dimensional grid data model is reconstructed using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model;

[0015] The terrain slope is calculated based on the reconstructed three-dimensional grid data model, the terrain slope factor of each partition is obtained, and the seabed base surface calculation data set is constructed;

[0016] The base surface elevation for wind turbine foundation scour analysis is calculated based on the seabed base surface calculation data set.

[0017] As a preferred implementation manner of the present invention, the model spacing of the original three-dimensional grid data model is 0.5 m, and each grid coordinate is expressed as (x, y, h).

[0018] As a preferred embodiment of the present invention, the thickness of the shallow silt is calculated based on the high-frequency bathymetric data and the low-frequency bathymetric data as follows:

[0019] The high-frequency bathymetric data and the low-frequency bathymetric data are converted into elevation through water depth to obtain high-frequency elevation data H1 and low-frequency elevation data H2. The thickness H of the shallow silt is calculated based on the high-frequency elevation data H1 and the low-frequency elevation data H2. a , expressed as:

[0020] H a =H1-H2.

[0021] As a preferred embodiment of the present invention, the thickness of the sediment layer in each wind turbine foundation area is determined as follows:

[0022] The stratum distribution data is compared with the stratum distribution data of the wind turbine foundation. If the actual thickness of the mud layer is consistent with the thickness of the mud layer in the construction drawing, the thickness of the mud layer in the stratum distribution data of the wind turbine foundation is the thickness of the mud layer; otherwise, the thickness of the mud layer in the stratum distribution data is used as the thickness of the mud layer.

[0023] As a preferred embodiment of the present invention, the water flow data includes the critical velocity and the water flow velocity at the average water depth; the theoretical scour depth of each wind turbine foundation area is calculated based on the water flow data using the semi-analytical balanced scour formula. Specifically, the scour depth S under the action of water flow alone is calculated based on the water flow data and the semi-analytical balanced scour formula. c , S c As the theoretical scouring depth H for each wind turbine foundation area c ,in:

[0024] The semi-analytical balanced scour formula is as follows:

[0025]

[0026] Where V c is the critical velocity at the average water depth, V is the water velocity, and D is the equivalent diameter of the fan foundation.

[0027] As a preferred implementation of the present invention, the specific steps of obtaining the reconstructed three-dimensional grid data model are as follows:

[0028] The height H in the grid coordinates is calculated based on the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scour depth of each wind turbine foundation area, and is expressed as:

[0029] H=h-max(H a ,H b ,H c );

[0030] In the formula, H b is the thickness of the sediment layer;

[0031] A reconstructed three-dimensional grid data model is obtained based on the grid elevation H and the original three-dimensional topographic data, and the reconstructed three-dimensional grid data model is partitioned into 1*1m grids.

[0032] As a preferred embodiment of the present invention, the terrain slope is calculated based on the reconstructed three-dimensional grid data model, which is expressed as follows:

[0033]

[0034] In the formula, △h is the maximum height difference of the current partition, d is the average side length of the current partition, and Ds is the slope percentage;

[0035] The terrain slope factor P is assigned a value based on the slope percentage, which is expressed as follows:

[0036]

[0037] The terrain slope factor of each grid partition in the reconstructed three-dimensional grid data model is assigned, and the average elevation corresponding to the grid partition with a terrain slope factor less than or equal to 0.6 is included in the seabed base surface calculation data set.

[0038] As a preferred embodiment of the present invention, the reference surface elevation for wind turbine foundation scour analysis is calculated based on the seabed base surface calculation data set as follows:

[0039] A seabed base surface calculation data set corresponding to each wind turbine is obtained, and an average value of the seabed base surface calculation data set is calculated, and the average value is used as the reference surface elevation for foundation scour analysis of the corresponding wind turbine.

[0040] On the other hand, the present invention also provides a system for determining the base elevation of an offshore wind turbine foundation scour analysis, the system comprising a data acquisition module, a data preprocessing module, a shallow silt thickness calculation module, a sediment layer thickness calculation module, a theoretical scour depth calculation module, a three-dimensional grid data model reconstruction module, a terrain slope calculation module and a base elevation calculation module, wherein:

[0041] The data acquisition module is used to collect seabed three-dimensional point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment;

[0042] The data preprocessing module is used to perform three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and perform grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model;

[0043] The shallow silt thickness calculation module is used to calculate the thickness of the shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data;

[0044] The sediment layer thickness calculation module is used to obtain stratum distribution data based on shallow profile data, including the depth and thickness of different strata, and determine the sediment layer thickness of each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing;

[0045] The theoretical scour depth calculation module is used to calculate the theoretical scour depth of each wind turbine foundation area based on water flow data using a semi-analytical balanced scour formula;

[0046] The reconstructed three-dimensional grid data model module is used to reconstruct the original three-dimensional grid data model using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model;

[0047] The terrain slope calculation module is used to calculate the terrain slope based on the reconstructed three-dimensional grid data model, obtain the terrain slope factor of each partition, and construct a seabed base surface calculation data set;

[0048] The reference surface elevation calculation module is used to calculate the reference surface elevation for wind turbine foundation scour analysis based on the seabed base surface calculation data set.

[0049] On the other hand, the present invention further provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for determining the elevation of a reference plane for scour analysis of an offshore wind turbine foundation as described in any embodiment of the present invention is implemented.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The present invention provides a method and system for determining the datum elevation of offshore wind turbine foundation scour analysis. By integrating multi-source data (such as seabed three-dimensional point cloud, high-frequency and low-frequency bathymetric data, shallow profile data and water flow data), combined with three-dimensional modeling, grid processing, stratigraphic distribution analysis and calculation of theoretical scour depth, a refined reconstruction of the landform of the offshore wind turbine foundation area is achieved; based on the reconstructed three-dimensional grid data model, a seabed base surface calculation data set suitable for scour analysis is constructed by screening the terrain slope factor, and finally the datum elevation of the wind turbine foundation scour analysis is accurately calculated, which improves the accuracy and scientificity of the datum elevation determination, provides reliable data support for the stability assessment and design optimization of the offshore wind turbine foundation, significantly reduces the structural safety risk caused by scour, and improves the overall safety of the offshore wind farm. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a flow chart of a method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0053] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0054] The present invention provides the following technical solution: a method and system for determining the elevation of a reference surface for scour analysis of an offshore wind turbine foundation.

[0055] Embodiment 1:

[0056] This embodiment provides a method for determining the elevation of a datum surface for scour analysis of an offshore wind turbine foundation, the method comprising:

[0057] S1. Collect seabed 3D point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment;

[0058] Furthermore, in this embodiment:

[0059] S11, collecting three-dimensional point cloud data of the seabed through a multi-beam sonar system, wherein the multi-beam sonar system transmits multiple sound beams to the seabed, receives echo signals, and calculates the round-trip time of the sound waves, thereby obtaining the height information of the seabed; through multiple scans, high-precision three-dimensional point cloud data of the seabed is generated;

[0060] S12, collecting high-frequency sounding data and low-frequency sounding data by single-beam sonar, wherein the single-beam sonar transmits a single sound beam to the seabed, receives the echo signal, and calculates the round-trip time of the sound wave, thereby obtaining the seabed depth, wherein the high-frequency sounding data uses a higher frequency sound wave, has a higher resolution, but has a weaker penetration; the low-frequency sounding data uses a lower frequency sound wave, has a stronger penetration, but has a lower resolution;

[0061] S13, obtaining shallow profile data by using a shallow stratum profiler, wherein the shallow stratum profiler emits low-frequency sound waves, penetrates the seabed surface, identifies the boundaries of different strata, and obtains stratum distribution data based on the identification results, including the depth and thickness of different strata;

[0062] S14, collecting water flow data by using an acoustic Doppler current meter, wherein the acoustic Doppler current meter transmits sound waves into the water body, receives echo signals, and calculates the water flow velocity by using the Doppler effect; the acoustic Doppler current meter can simultaneously measure the water flow velocity and direction in water layers of different depths;

[0063] S2, performing three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and performing grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model;

[0064] Furthermore, the model spacing of the original three-dimensional grid data model is 0.5m, and each grid coordinate is represented by (x, y, h);

[0065] S3, calculating the thickness of the shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data;

[0066] Specifically, the high-frequency bathymetric data and the low-frequency bathymetric data are converted into elevation through water depth to obtain high-frequency elevation data H1 and low-frequency elevation data H2, which have the same plane position; the thickness H of the shallow silt is calculated based on the high-frequency elevation data H1 and the low-frequency elevation data H2. a , expressed as:

[0067] H a =H1-H2;

[0068] S4, obtaining stratum distribution data based on the shallow profile data, including the depth and thickness of different strata, and determining the thickness of the sediment layer in each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing;

[0069] The stratum distribution data of the wind turbine foundation in the wind turbine foundation construction drawing is obtained during the design period. The stratum distribution data is compared with the stratum distribution data of the wind turbine foundation. If the actual thickness of the mud layer is consistent with the thickness of the mud layer in the construction drawing, the thickness of the mud layer in the stratum distribution data of the wind turbine foundation is the thickness of the mud layer; otherwise, the thickness of the mud layer in the stratum distribution data is used as the thickness of the mud layer;

[0070] S5. Based on the water flow data, the theoretical scour depth of each wind turbine foundation area is calculated using a semi-analytical balanced scour formula;

[0071] Water flow data include critical velocity and water velocity at average water depth;

[0072] The theoretical scouring depth of each wind turbine foundation area is calculated based on the water flow data using the semi-analytical balanced scouring formula. Specifically, the scouring depth S under the action of water flow alone is calculated based on the water flow data and the semi-analytical balanced scouring formula. c , S c As the theoretical scouring depth H for each wind turbine foundation area c ,in:

[0073] The semi-analytical balanced scour formula is as follows:

[0074]

[0075] Where V c is the critical velocity at the average water depth, V is the water velocity, and D is the equivalent diameter of the fan foundation;

[0076] Furthermore, the critical velocity V at the average water depth is obtained. c The steps include:

[0077] Determine the median particle size d of sediment through field sampling or historical data 50 (unit: m);

[0078] Based on the median particle size of sediment 50 Calculation of critical shear stress τ c , expressed as:

[0079]

[0080] In the formula, ρ represents the density of water, which is 1000 kg / m 3 ; g represents the acceleration due to gravity, which is 9.81 m / s 2 ρ s Indicates the density of sediment, take 2650kg / m 3 ;τ0 represents the critical Shields parameter, which is 0.047;

[0081] The critical shear stress τ c Calculate the critical velocity V at the average water depth c , expressed as:

[0082]

[0083] In the formula, C f is the friction coefficient, n is the Manning roughness coefficient. According to different substrate types, the Manning roughness coefficient has corresponding empirical values, such as n∈[0.012,0.015] for cement channels, n∈[0.022,0.025] for stone channels, n∈[0.025,0.030] for clay channels, n∈[0.012,0.015] for concrete pipes, and n∈[0.025,0.040] for silt riverbeds;

[0084] In order to improve the accuracy, the Manning roughness coefficient is derived by reverse calculation based on the flow velocity, water depth and bottom slope in the data collected by field measurement equipment on site, which is expressed as:

[0085]

[0086] Where V avg is the average flow velocity, R is the hydraulic radius, and S is the bottom slope;

[0087] Among them, the hydraulic radius R is calculated by combining the water depth with the geometric parameters of the channel. The corresponding relationship is calculated according to the cross-sectional shape of the channel, which will not be repeated here;

[0088] S6, reconstructing the original three-dimensional grid data model using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model;

[0089] The height H in the grid coordinates is calculated based on the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scour depth of each wind turbine foundation area, and is expressed as:

[0090] H=h-max(H a ,H b ,H c );

[0091] In the formula, H b is the thickness of the sediment layer;

[0092] A reconstructed three-dimensional grid data model is obtained based on the grid elevation H and the original three-dimensional topographic data, wherein the reconstructed three-dimensional grid data model removes the elevation influence caused by the dynamics of floating sediment on the seabed and the surface silt, thereby ensuring that the seabed within a certain range of the wind turbine foundation is not affected by the short-term dynamics of the ocean current;

[0093] Furthermore, in the original 3D grid data model, the distribution of corresponding data points of the seabed 3D point cloud data collected by the multi-beam sonar system is dense enough to accurately capture the changes and details of the seabed terrain, meeting the requirements of high precision. The original 3D grid data model can take a distance requirement of 0.5 units; and the reconstructed 3D grid data model combines multi-source data to obtain the reference surface. After correction and optimization of the reference surface, the model can still accurately reflect the actual terrain characteristics of the seabed under a larger scale of grid division. By increasing the grid spacing from 0.5 units to 1 unit, the number of grids is significantly reduced, which reduces the amount of data and the complexity of calculation. This not only improves the calculation rate, but also reduces the burden of storage and processing. Therefore, the reconstructed 3D grid data model is divided into 1*1m grids.

[0094] S7. Calculate the terrain slope based on the reconstructed three-dimensional grid data model, obtain the terrain slope factor of each partition, and construct a seabed base surface calculation data set, wherein the terrain slope factor is a dimensionless parameter, usually between 0 and 1, used to quantify the influence of the terrain slope on a certain process. The larger the terrain slope factor, the greater the influence of the slope on the process; the smaller the terrain slope factor, the smaller the influence of the slope on the process;

[0095] S71. Calculate the terrain slope based on the reconstructed three-dimensional grid data model, expressed as follows:

[0096]

[0097] In the formula, △h is the maximum height difference of the current partition, d is the average side length of the current partition, and Ds is the slope percentage;

[0098] S72, assigning a terrain slope factor P based on the slope percentage, expressed as:

[0099]

[0100] S73, assigning a value to the terrain slope factor of each grid partition in the reconstructed three-dimensional grid data model, and including the average elevation corresponding to the grid partition with a terrain slope factor less than or equal to 0.6 into the seabed base surface calculation data set, that is, when S is 1.0, the average elevation of the points in the grid partition is not included in the seabed base surface calculation data set;

[0101] S8. Calculate and obtain a reference surface elevation for wind turbine foundation scour analysis based on the seabed base surface calculation data set;

[0102] Specifically, a seabed base surface calculation data set corresponding to each wind turbine is obtained, and an average value of the seabed base surface calculation data set is calculated, and the average value is used as the reference surface elevation for foundation scour analysis of the corresponding wind turbine.

[0103] Embodiment 2:

[0104] This embodiment provides a system for determining the datum elevation of an offshore wind turbine foundation scour analysis, the system comprising a data acquisition module, a data preprocessing module, a shallow silt thickness calculation module, a sediment layer thickness calculation module, a theoretical scour depth calculation module, a three-dimensional grid data model reconstruction module, a terrain slope calculation module and a datum elevation calculation module, wherein:

[0105] The data acquisition module is used to collect seabed three-dimensional point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment;

[0106] The data preprocessing module is used to perform three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and perform grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model;

[0107] The shallow silt thickness calculation module is used to calculate the thickness of the shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data;

[0108] The sediment layer thickness calculation module is used to obtain stratum distribution data based on shallow profile data, including the depth and thickness of different strata, and determine the sediment layer thickness of each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing;

[0109] The theoretical scour depth calculation module is used to calculate the theoretical scour depth of each wind turbine foundation area based on water flow data using a semi-analytical balanced scour formula;

[0110] The reconstructed three-dimensional grid data model module is used to reconstruct the original three-dimensional grid data model using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model;

[0111] The terrain slope calculation module is used to calculate the terrain slope based on the reconstructed three-dimensional grid data model, obtain the terrain slope factor of each partition, and construct a seabed base surface calculation data set;

[0112] The reference surface elevation calculation module is used to calculate the reference surface elevation for wind turbine foundation scour analysis based on the seabed base surface calculation data set.

[0113] Embodiment 3:

[0114] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, a method for determining a reference surface elevation for scour analysis of an offshore wind turbine foundation as described in any embodiment is implemented.

[0115] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for determining the elevation of a datum surface for scour analysis of an offshore wind turbine foundation, characterized in that: The method comprises: Collect seabed 3D point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment; Performing three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and performing grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model; Calculating the thickness of shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data; Obtaining stratum distribution data based on shallow profile data, including the depth and thickness of different strata, and determining the thickness of the sediment layer in each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing; The theoretical scour depth of each wind turbine foundation area is calculated using a semi-analytical balanced scour formula based on water flow data; The original three-dimensional grid data model is reconstructed using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model; The terrain slope is calculated based on the reconstructed three-dimensional grid data model, the terrain slope factor of each partition is obtained, and the seabed base surface calculation data set is constructed; The base surface elevation for wind turbine foundation scour analysis is calculated based on the seabed base surface calculation data set.

2. The method for determining the elevation of the offshore wind turbine foundation scour analysis reference surface according to claim 1, characterized in that: The model spacing of the original three-dimensional grid data model is 0.5m, and each grid coordinate is represented by (x, y, h).

3. The method for determining the elevation of the offshore wind turbine foundation scour analysis reference surface according to claim 2, characterized in that: The thickness of the shallow silt calculated based on the high-frequency and low-frequency bathymetric data is as follows: The high-frequency bathymetric data and the low-frequency bathymetric data are converted into elevation through water depth to obtain high-frequency elevation data H1 and low-frequency elevation data H2. The thickness H of the shallow silt is calculated based on the high-frequency elevation data H1 and the low-frequency elevation data H2. a , expressed as: H a =H1-H2。 4. A method for determining the elevation of an offshore wind turbine foundation scour analysis reference surface according to claim 3, characterized in that: The thickness of the sediment layer in each wind turbine foundation area is determined as follows: The stratum distribution data is compared with the stratum distribution data of the wind turbine foundation. If the actual thickness of the mud layer is consistent with the thickness of the mud layer in the construction drawing, the thickness of the mud layer in the stratum distribution data of the wind turbine foundation is the thickness of the mud layer; otherwise, the thickness of the mud layer in the stratum distribution data is used as the thickness of the mud layer.

5. The method for determining the elevation of the offshore wind turbine foundation scour analysis reference surface according to claim 4, characterized in that: Water flow data include critical velocity and water velocity at average water depth; The theoretical scouring depth of each wind turbine foundation area is calculated based on the water flow data using the semi-analytical balanced scouring formula. Specifically, the scouring depth S under the action of water flow alone is calculated based on the water flow data and the semi-analytical balanced scouring formula. c , S c As the theoretical scouring depth H for each wind turbine foundation area c ,in: The semi-analytical balanced scour formula is as follows: Where V c is the critical velocity at the average water depth, V is the water velocity, and D is the equivalent diameter of the fan foundation.

6. A method for determining the elevation of an offshore wind turbine foundation scour analysis reference surface according to claim 5, characterized in that: The specific steps of obtaining the reconstructed three-dimensional grid data model are as follows: The height H in the grid coordinates is calculated based on the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scour depth of each wind turbine foundation area, and is expressed as: H=h-max(H a ,H b ,H c ); In the formula, H b is the thickness of the sediment layer; A reconstructed three-dimensional grid data model is obtained based on the grid elevation H and the original three-dimensional topographic data, and the reconstructed three-dimensional grid data model is partitioned into 1*1m grids.

7. A method for determining the elevation of an offshore wind turbine foundation scour analysis reference surface according to claim 6, characterized in that: The terrain slope is calculated based on the reconstructed three-dimensional grid data model, which is expressed as follows: In the formula, △h is the maximum height difference of the current partition, d is the average side length of the current partition, and Ds is the slope percentage; The terrain slope factor P is assigned a value based on the slope percentage, which is expressed as follows: The terrain slope factor of each grid partition in the reconstructed three-dimensional grid data model is assigned, and the average elevation corresponding to the grid partition with a terrain slope factor less than or equal to 0.6 is included in the seabed base surface calculation data set.

8. A method for determining the elevation of an offshore wind turbine foundation scour analysis reference surface according to claim 7, characterized in that: The base elevation of the wind turbine foundation scour analysis calculated based on the seabed base surface calculation data set is specifically: A seabed base surface calculation data set corresponding to each wind turbine is obtained, and an average value of the seabed base surface calculation data set is calculated, and the average value is used as the reference surface elevation for foundation scour analysis of the corresponding wind turbine.

9. A system for determining the elevation of a reference surface for scour analysis of offshore wind turbine foundations, characterized in that: The system includes a data acquisition module, a data preprocessing module, a shallow silt thickness calculation module, a sediment layer thickness calculation module, a theoretical scour depth calculation module, a three-dimensional grid data model reconstruction module, a terrain slope calculation module and a reference surface elevation calculation module, wherein: The data acquisition module is used to collect seabed three-dimensional point cloud data, high-frequency bathymetric data, low-frequency bathymetric data, shallow profile data and water flow data through field measurement equipment; The data preprocessing module is used to perform three-dimensional modeling based on the seabed three-dimensional point cloud data to obtain original three-dimensional landform data of the offshore wind turbine foundation area, and perform grid processing on the original three-dimensional landform data to obtain an original three-dimensional grid data model; The shallow silt thickness calculation module is used to calculate the thickness of the shallow silt based on the high-frequency bathymetric data and the low-frequency bathymetric data; The sediment layer thickness calculation module is used to obtain stratum distribution data based on shallow profile data, including the depth and thickness of different strata, and determine the sediment layer thickness of each wind turbine foundation area according to the stratum distribution data and the wind turbine foundation stratum distribution data in the wind turbine foundation construction drawing; The theoretical scour depth calculation module is used to calculate the theoretical scour depth of each wind turbine foundation area based on water flow data using a semi-analytical balanced scour formula; The reconstructed three-dimensional grid data model module is used to reconstruct the original three-dimensional grid data model using the thickness of the shallow silt, the thickness of the silt layer in each wind turbine foundation area, and the theoretical scouring depth of each wind turbine foundation area to obtain a reconstructed three-dimensional grid data model; The terrain slope calculation module is used to calculate the terrain slope based on the reconstructed three-dimensional grid data model, obtain the terrain slope factor of each partition, and construct a seabed base surface calculation data set; The reference surface elevation calculation module is used to calculate the reference surface elevation for wind turbine foundation scour analysis based on the seabed base surface calculation data set.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method for determining the elevation of the offshore wind turbine foundation scour analysis reference surface as described in any one of claims 1 to 8 is implemented.

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