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CN-122022213-A - Comprehensive evaluation method and system for offshore sea conditions

CN122022213ACN 122022213 ACN122022213 ACN 122022213ACN-122022213-A

Abstract

The invention discloses a comprehensive evaluation method and a comprehensive evaluation system for offshore sea conditions, and relates to the technical field of ocean hydrology and ocean wind energy resource utilization. The method comprises the steps of obtaining an initial data set of a wind field, a shoreline, a water depth and a tide level of a sea area to be researched, generating a predicted data set through a numerical model of hydrodynamic force and wave bidirectional coupling, adopting a layered super-parameter optimization strategy to carry out iterative adjustment on model parameters, controlling relative errors to be within 5% by combining measured data, generating extreme working condition data by fusing a platform wind field and a background wind field, carrying out comprehensive analysis on tide, wave, tide and storm tide characteristic parameters on the predicted data output by the model, and generating a sea condition comprehensive evaluation report. The invention improves the calibration efficiency and the simulation precision of model parameters, reduces the survey cost of offshore sea condition evaluation, and can be widely applied to site selection and feasibility analysis of offshore projects such as offshore wind power, port construction and the like.

Inventors

  • LI SHICHANG
  • LI NA
  • WANG YINGYU
  • REN ZHAOFEI
  • ZHAO QING
  • Shen Duhan
  • YU XINTONG

Assignees

  • 中国电力工程顾问集团西北电力设计院有限公司

Dates

Publication Date
20260512
Application Date
20260416

Claims (10)

  1. 1. The comprehensive offshore sea condition assessment method is characterized by being realized based on a numerical model of hydrodynamic force and wave bidirectional coupling, and comprises the following steps of: step 1, obtaining a model grid file and an initial data set of a wind field, a shoreline, a water depth and a tide level in a sea area coordinate range to be researched, and generating a prediction data set through a numerical model; Step 2, carrying out error analysis on the predicted data and the existing measured data in the predicted data set, and adopting a hierarchical super-parameter optimization strategy to adjust the numerical model parameters and the initial data set until the relative error between the numerical model predicted data and the existing measured data is smaller than a set threshold value, so as to obtain an adjusted numerical model; And 3, combining historical typhoon data in the sea area to be researched, generating new typhoon data by using a coast and ocean hydrodynamic force numerical simulation module in the numerical model, inputting the new typhoon data into the adjusted numerical model to operate so as to obtain predicted data, and analyzing characteristic parameters of water level, tide, wave, ocean current and storm surge to the predicted data so as to obtain an evaluation result.
  2. 2. The method of claim 1, wherein in step1, obtaining a model grid file and an initial data set of a wind field, a shoreline, a water depth and a tide level within a coordinate range of a sea area to be researched comprises: extracting a shoreline coordinate and generating a shp format file, converting the generated shp format file into a xyz format file, opening the generated xyz format file by MIKE MESH GENERATE blocks, and generating a grid file of the model after removing repeated points and cross lines; acquiring data of transverse and longitudinal average wind speeds and sea level atmospheric pressure for one year or more from the public data set, wherein a wind field file of the numerical model hydrodynamic module comprises wind speed and sea level atmospheric pressure data, and a wind field file of the wave module comprises wind speed data; Importing global tide level model data, matching the time dimension and the total simulation time length of numerical simulation, importing the data into a grid file of the model to generate tide level boundary tide level data of the sea area to be researched, inputting an initial data set and the tide level boundary data into a numerical model with hydrodynamic force and wave coupled in two directions, and generating a prediction data set of tide level, tide, wave and water level through calculation of the numerical model; The hydrodynamic module numerical model calculation comprises water flow mass and momentum conservation calculation, turbulence closed simulation, wind stress driving calculation, bed surface resistance dissipation calculation, coriolis force effect calculation and wave radiation stress coupling calculation, and the wave module numerical model calculation comprises wave action conservation calculation, wind energy input calculation, white cap dissipation calculation, water depth induced crushing control calculation, bottom friction dissipation calculation and wave diffraction effect simulation.
  3. 3. The comprehensive offshore sea condition assessment method according to claim 1, wherein the numerical model with the hydrodynamic force and wave bidirectional coupling is a numerical model with the real-time bidirectional data interaction capability of a hydrodynamic force process and a wave process, specifically a MIKE/3 Coupled model, a Delft3D FM model or a FVCOM hydrodynamic force model is adopted to couple a SWAN wave model, and the numerical model realizes the data interaction of a hydrodynamic force module and a wave module in an online bidirectional coupling mode and transmits water level, flow rate and wave radiation stress parameters in real time.
  4. 4. The method for comprehensive assessment of offshore conditions according to claim 1, wherein step 2 specifically comprises the steps of: Performing error analysis on the predicted data and the existing measured data in the predicted data set, and calculating the relative error of the predicted data and the existing measured data, wherein if the relative error is more than or equal to 5%, a hierarchical super-parameter optimization strategy is adopted to adjust the numerical model parameters and the initial data set, and if the relative error is less than 5%, the calibrated high-precision numerical model is directly obtained; The method comprises the steps of generating a parameter importance weight matrix of initial data on the influence of a result through an automatic encoder and arranging the parameter importance weight matrix according to a weight descending order, generating a main component analysis weight matrix of model parameters on the influence of the result through main component analysis and arranging the weight matrix according to the weight descending order, combining the main component analysis weight matrix and the parameter importance weight matrix arranged according to the descending order to obtain comprehensive weight matrix data, taking the comprehensive weight matrix data as input and relative error as output, carrying out hierarchical screening and calculating resource redistribution by combining the parameter importance reflected by the weight matrix through deep learning of the hierarchical super parameter optimization strategy; repeating the iterative steps until the relative error between the predicted data set and the measured data is less than 5%, and obtaining the calibrated high-precision numerical model.
  5. 5. The method for comprehensive evaluation of offshore conditions according to claim 4, wherein the mandatory physical constraints of adding the lower limit of the optimization priority and the feasible parameter domain in the optimization process are as follows: Optimizing a priority lower limit constraint: Parameter feasible domain physical constraints: wherein: is a composite weight matrix of the weight matrix, Representing the physical parameter index, Ω phy is the key physical parameter set, w min is the optimization priority lower limit, 、 The lower and upper limits of the feasible region for the jth physical parameter, respectively.
  6. 6. The method for comprehensively evaluating the offshore sea condition according to claim 1, wherein in the step 3, the numerical model automatically matches the input characteristic parameter values with the standards in the rule base, judges the states, grades and risks of various characteristic parameters corresponding to water levels, tides, waves, ocean currents and storm tides, combines the physical relevance among the characteristic parameters, and automatically marks the precision of the predicted result according to the comparison of the numerical model predicted data and the measured data.
  7. 7. The method of claim 1, wherein in step 3, generating new typhoon data using the coast and ocean hydrodynamic force numerical simulation module in the numerical model comprises: the platform wind field and the background wind field are fused by adopting a dynamic weight formula, and the calculation formula is as follows: wherein V C is a mixed wind field after fusion, V M is a typhoon wind field, V Q is a background wind field, r 0 is a maximum wind speed radius, r is a distance from a calculated point to a typhoon center, and e w is a weight coefficient.
  8. 8. A comprehensive evaluation system of offshore sea conditions is characterized by comprising a data acquisition module, a model calculation module, a parameter optimization calibration module and a sea condition evaluation output module, The output end of the data acquisition module is connected with the input end of the model calculation module, the output end of the model calculation module is respectively connected with the input ends of the parameter optimization calibration module and the sea state evaluation output module, and the output end of the parameter optimization calibration module is connected with the input end of the model calculation module; The data acquisition module is used for acquiring initial data of a wind field, a shoreline, a water depth and a tide level of a sea area to be ground, completing the data format conversion of the shoreline, generating a model grid file after removing the duplication and crossing lines, interpolating the water depth to the model grid file, acquiring continuous transverse and longitudinal average wind speed and sea level atmospheric pressure data for at least 1 year, constructing an initial data set, importing global tide level model data, and generating tide level boundary data of the sea area to be ground; The model calculation module is used for configuring a numerical model for bidirectionally coupling running hydrodynamic force and waves, receiving an initial data set and tide level boundary data, generating a prediction data set through bidirectionally coupling calculation of the hydrodynamic force module and the wave module, receiving optimized model parameters output by the parameter optimization calibration module and typhoon working condition wind field data, and running to obtain typhoon working condition full-factor prediction data, wherein the hydrodynamic force module covers water flow mass and momentum conservation, turbulence sealing, wind stress driving, bed surface resistance dissipation, coriolis force effect and wave radiation stress coupling calculation functions, and the wave module covers wave action, wind energy input, white cap dissipation, water depth induced crushing control, bottom friction dissipation and wave diffraction effect simulation functions; The parameter optimization calibration module is used for receiving the predicted data set output by the model calculation module, carrying out error analysis on the predicted data set and the existing measured data of the sea area to be researched, and calculating relative errors, when the relative errors are more than or equal to 5%, executing hierarchical super-parameter optimization, generating a parameter importance weight matrix through a neural network automatic encoder, generating a principal component analysis weight matrix through principal component analysis, merging to obtain a comprehensive weight matrix, carrying out hierarchical screening and calculation resource weight distribution according to the parameter weight by taking the comprehensive weight matrix as an input and the relative errors as an output, simultaneously adding a lower limit of optimization priority and forced physical constraint of a parameter feasible domain in the optimization process, and feeding back the optimized model parameters to the model calculation module until the relative errors of the predicted data set and the measured data are less than 5%, and completing model calibration; The sea state evaluation output module is internally provided with a sea state evaluation rule base and is used for generating typhoon working condition wind field data by combining historical typhoon data of a sea area to be researched and adopting a dynamic weight formula to fuse a typhoon wind field and a background wind field, and inputting the typhoon working condition wind field data into the calibrated model calculation module; the method comprises the steps of receiving typhoon working condition full-factor prediction data output by a model calculation module, analyzing characteristic parameters of four dimensions of tides, waves, tides and storm tides, matching the characteristic parameters with a sea condition evaluation rule base, generating and outputting an offshore sea condition comprehensive evaluation report containing tide attributes, wave element characteristics, tide characteristics and storm tides risk levels of a sea area to be researched, and specifically comprises the steps of judging accurate conversion relations of tide attributes, theoretical lowest tide level and average sea level of the sea area to be researched based on a field site tide level reconciliation analysis result, drawing an annual wave rose diagram based on a numerical simulation result, counting annual and seasonal occurrence frequencies of different wave levels and wave directions, analyzing influence rules of wave refraction, diffraction, crushing characteristics and wave flow interaction, judging tide attributes and tide motion forms based on a tide reconciliation analysis result, and outputting historical storm tides and storm water increasing statistical rules of the field site area, increasing characteristic differences, maximum water increasing values and water increasing season distribution characteristics of different paths typhoons.
  9. 9. A computer readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements a method for comprehensive assessment of offshore conditions according to any of claims 1-7.
  10. 10. An offshore engineering site selection method, characterized in that the output result of the comprehensive evaluation method of offshore conditions according to any one of claims 1-7 is used as the basis of engineering feasibility analysis, and the method comprises the following steps: verifying a theoretical depth datum plane of an offshore wind farm or a photovoltaic site; The wave load and the flow velocity load of the offshore wind turbine foundation are evaluated; And (5) analyzing the tidal range and flow rate adaptability of the harbor construction area.

Description

Comprehensive evaluation method and system for offshore sea conditions Technical Field The invention belongs to the technical field of ocean hydrology and ocean wind energy resource utilization, and particularly relates to a comprehensive evaluation method and system for offshore sea conditions. Background The annual average solar total radiation in coastal areas is high, the sea surface reflection effect can improve the power generation efficiency of the photovoltaic panel, the tidal energy technology can be developed in a large quantity, and the tidal energy technology is mainly concentrated in a region with significant tidal range. The energy has the advantages of zero pollution emission, renewable resources, large development scale and the like, is an important direction of energy structure transformation, is rich in offshore wind energy, light energy and tidal energy, and is valued and supported by various industries because the energy development has the advantages of no pollution, high utilization rate and the like. The sea conditions of the sea area and the photovoltaic field are considered, if the local sea conditions cannot be effectively evaluated, the cost is increased, the efficiency is low, and the structural damage of the sea worker is caused seriously. The current collection of offshore hydrologic data relies mainly on-site in-situ observation and numerical simulation of two technical routes. In current engineering practice, it is often necessary to set up hydrologic monitoring stations locally and to conduct continuous observations for decades to acquire sea hydrologic data. The acquisition of the hydrologic data often requires a large amount of manpower and material resources, so that the data cost is high, the period is long, and the requirements of related departments for quick and efficient evaluation of the hydrologic information are difficult to meet. The sensitivity difference of different types of energy development to sea state parameters is not monitored in a targeted manner, for example, a photovoltaic field needs to pay attention to water quality transparency, and related sensors are not configured in the prior hydrologic station generally, so that input parameters of an evaluation model are lost. The wind power plant position layout depends on an accurate wind resource map, the power curve prediction deviation is caused by sparse measuring points, the floating body displacement calculation of the photovoltaic field is out of alignment due to ocean currents, extra intervals are reserved, and the utilization rate is reduced. The tidal power station is insufficient in tidal current flow speed monitoring, and the unit impeller is in an inefficient working condition for a long time. Taking offshore wind power as an example, equipment such as a flow velocity meter, a wave height meter, a temperature and salt depth meter and the like is required to be deployed at a single monitoring station, technical problems such as corrosion, ocean current impact and the like are overcome, construction cost is high, professional ships are required to be calibrated regularly for equipment operation and maintenance, single maintenance cost of the deep sea monitoring station reaches hundreds of thousands of yuan, the contradiction between the economy and timeliness of data acquisition is prominent, in addition, the current hydrological data measuring points are scattered and are usually separated from an evaluation area by tens of kilometers or even more, sea conditions of the area to be evaluated cannot be fully reflected, and the data loss causes overlarge offshore sea condition evaluation error. Numerical simulation technology is an important technical means for solving the problems of high in-situ observation cost and long period, and a plurality of related patent applications are disclosed in the prior art about the numerical simulation of offshore sea conditions. For example, the patent application with publication number CN105824993a adopts a hydrodynamic and wave coupling model to perform numerical simulation on the near shore tide, flow field and wave process, and performs model parameter determination by combining measured data. However, the method generally depends on manual experience in the parameter adjustment process, has the problems of low parameter adjustment efficiency and insufficient result consistency, and is not a systematic simulation method under the extreme sea condition. In the aspect of extreme sea state simulation, the patent application with the publication number of CN110287504A simulates based on design waves and historical typhoon processes, but the defects still exist in the aspects of multi-element coupling and dynamic response, particularly in the aspects of insufficient consideration of nonlinear interaction of tides, tides and waves, limited dynamic response capability to typhoon time-varying wind fields and boundary conditions, and difficulty in accurately reflec