CN-122021401-A - Offshore typhoon wave refined simulation method based on terrain self-adaptive grid and parameter dynamic correction

CN122021401ACN 122021401 ACN122021401 ACN 122021401ACN-122021401-A

Abstract

The invention relates to the technical field of marine environment numerical simulation, in particular to a near-shore typhoon wave refined simulation method based on terrain self-adaptive grid and parameter dynamic correction, which comprises the steps of obtaining basic data and simulation parameters of a target sea area, constructing a calculation domain and an initial grid, wherein the initial grid is an unstructured grid fused with multiple physical constraint factors; the method comprises the steps of optimizing an initial grid based on a numerical stability criterion to obtain a final calculation grid meeting calculation convergence requirements, establishing a bidirectional coupling model, applying the final calculation grid to the bidirectional coupling model, carrying out localized iteration calibration on key physical parameters of the bidirectional coupling model to obtain an optimal parameter set, carrying out typhoon wave process simulation calculation by utilizing the final calculation grid and the optimal parameter set, and constructing a typhoon wave characteristic database.

Inventors

Chu Fushuo
WANG WEIZHU
PENG CHENG
ZHAO ZHIGANG
LIU SHIWU
Cao Zhongsen
LIU JIANLAN

Assignees

福建永福电力设计股份有限公司

Dates

Publication Date: 20260512
Application Date: 20251229

Claims (10)

1. A method for finely simulating near-shore typhoon waves based on terrain self-adaptive grids and parameter dynamic correction is characterized by comprising the following steps: step 1, acquiring basic data and simulation parameters of a target sea area; Step 2, constructing a calculation domain and an initial grid which are adaptive to the target sea area topography and typhoon influence characteristics, wherein the initial grid is an unstructured grid fused with multiple physical constraint factors; step3, optimizing the initial grid based on a numerical stability criterion to obtain a final calculation grid meeting the calculation convergence requirement; step 4, establishing a bidirectional coupling model comprising wind fields, storm tides and sea waves, and applying the final calculation grid to the bidirectional coupling model; Step 5, constructing a wave flow coupling dynamic bottom friction mechanism, utilizing measured data of a target sea area to establish an error feedback closed loop, and carrying out space-time localized inversion on typhoon wind field parameters and seabed physical attribute parameters to generate an optimal parameter set; And 6, carrying out simulation calculation on the typhoon wave process by utilizing the final calculation grid and the optimal parameter set, correcting the typhoon field parameters and the seabed physical attribute parameters in real time in the simulation process, and constructing a typhoon wave characteristic database.
2. The method for simulating the fine simulation of near-shore typhoons based on the terrain adaptive grid and the dynamic correction of parameters according to claim 1, wherein in the step 1, the basic data comprise terrain data, historical typhoons and actual marine environment data, and the simulation parameters comprise time integration step sizes; The topographic data is corrected by adopting SRTM15 arc-second water depth grid data and coastal sea area navigation actual measurement data; historical typhoon data uses CMA tropical cyclone best path datasets.
3. The method is characterized in that a computing domain is constructed in the specific mode of adopting a multistage nested elliptical sector boundary structure, wherein the multistage nested elliptical sector boundary structure at least comprises an outer elliptical boundary and an inner elliptical boundary, the outer elliptical boundary covers a typhoon far-field influence range, the long half axis direction of the outer elliptical boundary is consistent with a target sea area historical typhoon dominant path, the inner elliptical boundary focuses on a near-shore core concerned area, the center of the center is positioned as a target sea area key geographic unit center, and invalid land areas and non-concerned deep sea areas are removed by adjusting elliptical eccentricity, rotation angles and sector azimuth angles.
4. The method for simulating the fine simulation of the near-shore typhoon wave based on the terrain self-adaptive grid and the parameter dynamic correction is characterized in that the specific process of generating the initial grid in the step 2 is that a grid scale control function H (x, y) is constructed, the grid scale control function is formed by weighting shallow water wavelength constraint factors, terrain gradient response factors and grid gradient smoothing factors, the shallow water wavelength constraint factors ensure that a preset number of grid nodes are contained in unit wavelength, the terrain gradient response factors automatically encrypt the grid when the change rate of the terrain gradient of the seabed exceeds a preset threshold value, and the grid gradient smoothing factors control the transition growth rate of an inner-layer high-resolution grid to an outer-layer low-resolution grid.
5. The method for simulating the fine simulation of the near-shore typhoon wave based on the terrain self-adaptive grid and the dynamic correction of parameters according to claim 1, wherein the grid optimization processing in the step 3 specifically comprises the following steps: calculating the full-field Brownian number CFL of the initial grid under a preset time integral step; identifying high risk grid cells having a kulangerhans greater than a stability threshold; and deducing the minimum feature scale of the high-risk grid unit reversely according to the stability threshold value, and carrying out partial topology reconstruction or relaxation smoothing treatment on the regional grid until the full-field grid kurtosis meets the stability requirement.
6. The method for simulating the fine simulation of near-shore typhoon waves based on the terrain adaptive grid and the dynamic correction of parameters according to claim 1, wherein the grid optimization processing in the step 3 further comprises terrain gradient correction, gradient detection is carried out on the water depth data after grid interpolation, and when the terrain gradient between adjacent nodes exceeds a critical value, smooth correction is carried out on the water depth data.
7. The method for simulating the offshore typhoon wave refinement based on the terrain self-adaptive grid and the parameter dynamic correction is characterized in that a coupling numerical model system in the step 4 is constructed in a mode that a Holland typhoon model is adopted to generate a typhoon wind field, a ADCIRC model is adopted to calculate storm tide level and flow field, a SWAN model is adopted to calculate sea wave field, a ADCIRC model and the SWAN model share the final calculation grid, water level, flow speed and wave radiation stress data are exchanged in real time, and bidirectional coupling of storm tide, sea wave and tide is achieved.
8. The method for simulating the fine simulation of near-shore typhoon waves based on the terrain adaptive grid and the dynamic correction of parameters according to claim 1, wherein the method for simulating the fine simulation of near-shore typhoon waves based on the terrain adaptive grid and the dynamic correction of parameters is characterized by comprising the following steps: (1) The dynamic bottom friction function is constructed by introducing wave-stream interaction WCI theory and constructing a time-varying function of the bottom friction evolving along with the state of the flow field: ; Wherein the method comprises the steps of For the time-varying sole friction force m, Is the density of the seawater, and the seawater is the density of the seawater, Is determined by the nonlinearity of the fluctuating geometric parameters, In order to achieve a wave bottom track speed, Is the background flow rate; (2) The method comprises the steps of determining an observation vector and a control variable, wherein the effective wave height, the spectrum peak period and the actual measurement value of the tide level during typhoon are selected as the observation vector, and the median particle size of submarine sediments and the coefficient i of the air pressure shape of a wind field are selected as the control variables to be inverted; (3) Error feedback and parameter optimization, namely constructing a cost function in each time step or a preset time window of numerical simulation, calculating residual errors of simulation values and actual measurement values by utilizing an accompanying assimilation algorithm or gradient descent optimization algorithm, and dynamically adjusting the control variables to obtain an optimal submarine sediment particle size distribution field and an optimal instantaneous air pressure shape coefficient, wherein the cost function is as follows: ; Wherein, the In order to simulate the vector of the vector, In order to observe the vector of the light, Is a control parameter vector of the air pressure shape coefficient of the wind field, As the weight coefficient of the light-emitting diode, As a cost function; (4) And dynamically correcting, namely reconstructing the bottom friction coefficient field and the wind field driving force of the full-field grid node in real time according to the updated control variable, and realizing the dynamic correction of physical parameters along with the typhoon development process.
9. The method for accurately simulating the near-shore typhoon and wave based on the terrain self-adaptive grid and the parameter dynamic correction, which is disclosed in claim 1, is characterized in that the time span of simulation calculation in the step 6 is not less than 50 years, long-term sea condition data sets are generated by adopting continuous simulation every hour, and typhoon and wave characteristic databases comprise wind fields, wave fields, tide fields and tide level space-time distribution data in different reproduction periods, wherein the data are obtained through generalized extremum distribution or poisson distribution statistical model analysis.
10. The method for simulating the fine simulation of the near-shore typhoon wave based on the terrain self-adaptive grid and the dynamic parameter correction according to claim 1, wherein in the step 4, a wind field is driven by a combined wind field, the wind field of a Holland typhoon model and an ERA5 wind field are fused through a dynamic weighting formula to construct the combined wind field, and the weighting formula is as follows: ; Wherein, the Is a combined wind field; A wind field calculated for the Holland typhoon model; Analyzing the wind farm for ERA 5; Is a weight coefficient.

Description

Offshore typhoon wave refined simulation method based on terrain self-adaptive grid and parameter dynamic correction Technical Field The invention belongs to the technical field of marine environment numerical simulation, and particularly relates to a near-shore typhoon wave refined simulation method based on terrain self-adaptive grid and parameter dynamic correction. Background With the deep advancement of ocean national strategies, the construction scale of ocean infrastructures such as offshore wind power, cross-sea channels and the like is continuously enlarged, and the structural safety and the full life cycle reliability of the offshore wind power, cross-sea channels and the like are highly dependent on accurate ocean environment design parameters. The hydrodynamic conditions in regions such as southeast coast and Taiwan strait in China are extremely complex, are influenced by multiple modes of black tides, strong tides, monsoon and frequent typhoons, form a strong wave-tide-flow nonlinear coupling effect, and bring great challenges to typhoon wave simulation. The existing typhoon wave numerical simulation technology has two core defects that firstly, a model coupling mechanism is imperfect, most researches adopt storm tide, wave and tide models to drive unidirectionally or independently simulate frames, and neglect bidirectional feedback mechanisms between wave, tide and current, such as modulation of wave radiation stress on storm tide level, influence of tide on wave propagation and the like, so that extreme load simulation has systematic deviation, potential safety hazards or manufacturing cost redundancy are brought to engineering design, secondly, calculation grid adaptability and stability are insufficient, a traditional rectangular structured grid is difficult to fit a tortuous shoreline and a complex terrain, and key physical processes such as wave shallow water deformation, refraction and diffraction cannot be accurately depicted due to low simulation resolution of a near-shore key engineering area. Although there are attempts of unstructured grid models, the method is limited to single typhoon individual inversion, and is lack of self-adaptive optimization based on numerical stability, calculation stability of complex terrains under large time steps is difficult to guarantee, and popularization and application of the method are limited. In addition, the existing method lacks a physical parameter localization dynamic correction mechanism aiming at a specific sea area, and general parameters cannot be adapted in different sea areas, so that the simulation precision is insufficient, and the requirement of ocean engineering on high-precision design parameters cannot be met. Therefore, development of a typhoon wave refined simulation method integrating a self-adaptive grid, a bidirectional coupling model and a parameter dynamic correction mechanism is needed, and the technical defects are fundamentally overcome. Disclosure of Invention In order to solve the problems, the invention provides a near-shore typhoon wave refined simulation method based on terrain self-adaptive grid and parameter dynamic correction, which realizes high-precision simulation and prediction of the typhoon wave process by constructing a self-adaptive optimization grid, establishing a bidirectional coupling model and a parameter localization calibration mechanism. The technical scheme of the invention is as follows: A method for finely simulating near-shore typhoon waves based on terrain self-adaptive grids and parameter dynamic correction comprises the following steps: step 1, acquiring basic data and simulation parameters of a target sea area; Step 2, constructing a calculation domain and an initial grid which are adaptive to the target sea area topography and typhoon influence characteristics, wherein the initial grid is an unstructured grid fused with multiple physical constraint factors; step3, optimizing the initial grid based on a numerical stability criterion to obtain a final calculation grid meeting the calculation convergence requirement; step 4, establishing a bidirectional coupling model comprising wind fields, storm tides and sea waves, and applying the final calculation grid to the bidirectional coupling model; Step 5, constructing a wave flow coupling dynamic bottom friction mechanism, utilizing measured data of a target sea area to establish an error feedback closed loop, and carrying out space-time localized inversion on typhoon wind field parameters and seabed physical attribute parameters to generate an optimal parameter set; And 6, carrying out simulation calculation on the typhoon wave process by utilizing the final calculation grid and the optimal parameter set, correcting the typhoon field parameters and the seabed physical attribute parameters in real time in the simulation process, and constructing a typhoon wave characteristic database. Further, in step 1, the basic data includes topographic data