A storm surge floodplain algorithm and device based on SCVT unstructured grid

Abstract

A storm surge floodplain algorithm and device based on SCVT unstructured grid, the method performs grid division and numbering according to the SCVT unstructured grid; respectively determines the indexing strategy of the adjacent grid cells of the grid cell, the grid edge corresponding to the grid cell, and the two adjacent grid cells of the grid edge; defines the model physical variables and sets the corresponding marking positions; when the numerical mode is initialized, the grid cell and the grid edge are respectively marked for dry and wet states; the numerical mode is integrated according to the set time step, and after the integration is completed in one step, the dry and wet change state of the grid cell is judged and marked by the dry-to-wet strategy and the wet-to-dry strategy, and the numerical mode integration is circulated within the set simulation time until the simulation ends, and the final dry and wet state of the grid cells in the simulation area and the floodplain inundation depth and other information are output. The floodplain algorithm designed by the present invention is based on the SCVT grid, has a local encryption function, and the calculation is more stable, and is more suitable for storm surge floodplain simulation.

Description

Technical Field

[0001] The invention relates to the technical field of computer algorithms, and in particular to a storm surge floodplain algorithm and device based on SCVT unstructured grid. Background Art

[0002] Floodplains caused by storm surges are currently important natural disasters that cause casualties and economic losses. The numerical model of storm surge floodplains is an important forecasting tool that can provide guidance for disaster prevention and mitigation.

[0003] The floodplain process is the process in which seawater gradually invades the land and then gradually retreats. The physical process of the floodplain is more complicated. In the calculation and solution process, it involves the dry grid becoming a wet grid to participate in the calculation and solution, and the wet grid becoming a dry grid to exit the calculation and solution.

[0004] The numerical model of storm surge floodplain is to discretize the partial differential equations (shallow water equations) that reflect the movement of seawater into grids for numerical solution, including triangular grids, equal longitude and latitude grids, etc.

[0005] At present, there are two main types of grids for mainstream storm surge floodplain models, equal longitude and latitude grids and triangular grids, both of which have certain shortcomings. Although the equal longitude and latitude grid has a simple discrete form and the model code is relatively easy to write, it does not have the ability to encrypt locally, and the global high resolution leads to a large amount of calculation. If the nested encryption method is used, that is, a small-scale high-resolution area is nested in a large-scale low-resolution grid, the boundary between the coarse and fine grids is prone to instability. Especially for floodplain simulation, the grid resolution is generally as high as tens of meters. This defect of the structural grid seriously restricts its application in the field of floodplain simulation. The triangular grid has the ability to encrypt locally, and can use high resolution for key areas and low resolution for non-key areas, saving computing resources while ensuring the simulation accuracy of key areas; however, the triangular grid often has some grids with too small sharp angles in the grid configuration. From the grid quality evaluation criteria, that is, the evaluation indicators of its skewness and aspect ratio are poor, and according to relevant research, the grid quality will affect the truncation error. In actual use, it is also found that in a grid with too small an acute angle, it is easy to cause calculation instability or even overflow, especially in a physical process that develops violently such as a floodplain.

[0006] SCVT (spherical centroidal Voronoi tessellation) grid is an unstructured hexagonal grid. SCVT grid is mainly composed of Voronoi hexagonal grids, and also has a small amount of pentagons or heptagons. SCVT has the ability of transitional encryption, so it can use high-resolution grids for key areas and low-variation rate grids for non-key areas, ensuring the simulation effect of key areas while saving computing resources. In recent years, SCVT grids have gradually been applied to storm surge numerical models.

[0007] Therefore, further proposing a floodplain algorithm process for the SCVT grid is a necessary prerequisite for applying the storm surge numerical model based on the SCVT grid to storm surge floodplain simulation and forecasting. Summary of the invention

[0008] To this end, the present invention provides a storm surge floodplain algorithm and device based on SCVT unstructured grid. Through this method, the current storm surge model based on SCVT grid can be applied to floodplain simulation and forecasting, broadening and improving the functions of the current such model. At the same time, compared with the floodplain algorithm based on equal longitude and latitude grid and triangular grid, it has a local encryption function and the calculation is more stable, which is more suitable for storm surge floodplain simulation.

[0009] In order to achieve the above object, the present invention provides the following technical solution: a storm surge floodplain algorithm based on SCVT unstructured grid, comprising:

[0010] Divide the simulation area into grids according to the SCVT unstructured grid, and number all grid cells and grid edges in the simulation area;

[0011] Determine the indexing strategy of the adjacent grid cells of the grid cell, the indexing strategy of the grid edge corresponding to the grid cell, and the indexing strategy of the two adjacent grid cells of the grid edge respectively;

[0012] Defining model physical variables and setting the marking positions of the model physical variables in the grid cells;

[0013] When the numerical mode is initialized, the grid cells and grid edges are marked for dry and wet states respectively;

[0014] Performing numerical model integration according to a set time step, calculating the influence of set factors on seawater through the integration step, and determining the values ​​of the physical variables of the model;

[0015] After the numerical mode integration is completed in one step, the wet-dry change state of the grid cell is confirmed; when the grid cell changes from a wet state to a dry state, if the grid cell is a dry grid cell, maskCell(iCell) is marked as 0, and the next grid cell is judged after marking; if the grid cell is a wet grid cell, it is judged according to the wet grid cell judgment strategy, and marked after the judgment is completed; when the grid cell changes from a dry state to a wet state, if the grid cell is a wet grid cell, maskCell(iCell) is marked as 1, and the next grid cell is judged after marking; if the grid cell is a dry grid cell, it is judged according to the dry grid cell judgment strategy, and marked after the judgment is completed;

[0016] The numerical model integration is cycled within the set simulation time, and the dry and wet states of the grid units are updated until the simulation is finished, and the final dry and wet states of the grid units in the simulation area are output.

[0017] As a preferred solution of the storm surge floodplain algorithm based on SCVT unstructured grid, the index strategy of the adjacent grid cells of the grid cell is: for the iCell grid cell, the indexes of its adjacent grids are cellsOnCell(1,iCell), cellsOnCell(2,iCell)...cellsOnCell(nCOC,iCell);

[0018] The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell);

[0019] The index strategy of the two adjacent grid cells of the grid edge is: for the iEdgeth edge, the indexes of the two adjacent grid cells on the left and right are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges) respectively.

[0020] As a preferred solution of the storm surge floodplain algorithm based on SCVT unstructured grid, in the process of defining the model physical variables, the model physical variables include storm surge flood depth, sea level water depth, total water depth, current velocity and the distance between two adjacent grid centers;

[0021] The marking positions of the model physical variables in the grid units are as follows: the storm surge depth, sea level depth, and total water depth model material variables are set at the center of the grid unit; the ocean current velocity model physical variables are set at the grid edge, and the direction is perpendicular to the grid edge.

[0022] As an optimal solution of the storm surge overland algorithm based on the SCVT unstructured grid, during the numerical model initialization, when marking the dry and wet states of grid cells and grid edges respectively, a grid cell without seawater is in the "dry" state, and a grid cell with seawater is in the "wet" state; maskCell(nCells) is used to mark the dry and wet states of grid cells, and maskEdge(nEdges) is used to mark the dry and wet states of grid edges. The wet state is 1, and the dry state is 0.

[0023] As an optimal solution of the storm surge overland algorithm based on the SCVT unstructured grid, when the cell grid is a wet grid cell, during the judgment process according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge water level rise h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0, and the flow velocity u(eoc) is 0;

[0024] When the cell grid is a dry grid cell, during the judgment process according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is: for the dry grid cell iCell, initialize the temporary counting variable count to 0 and the temporary accumulation variable temp to 0. Determine all adjacent grid cells of the dry grid cell iCell according to the index strategy of the adjacent grid cells of the grid cell. For the jth adjacent grid cell, calculate the water level difference deltaH; if deltaH > hMin, then increment the temporary counting variable count by 1, add deltaH to the temporary accumulation variable temp, and mark the dry and wet state of the grid edge maskEdge(eoc) as 1; when the determination of the nCOC adjacent grid cells is completed, if count > 0, then mark the dry and wet state of the dry grid cell iCell maskCell(iCell) as 1.

[0025] The present invention also provides a storm surge overland algorithm processing device based on the SCVT unstructured grid, adopting the above-mentioned storm surge overland algorithm based on the SCVT unstructured grid, including:

[0026] A grid division and numbering module, configured to divide the simulation area into grids according to the SCVT unstructured grid, and number all grid cells and grid edges within the simulation area;

[0027] An index strategy determination module, configured to determine the index strategy of adjacent grid cells of grid cells, the index strategy of grid edges corresponding to grid cells, and the index strategy of two adjacent grid cells of grid edges respectively;

[0028] A model physical variable definition module, used to define the model physical variables and set the marking positions of the model physical variables in the grid units;

[0029] An initial dry-wet state marking module is used to mark the dry-wet state of the grid cells and grid edges respectively when the numerical mode is initialized;

[0030] A numerical model integration module is used to perform numerical model integration according to a set time step, calculate the influence of set factors on seawater through the integration step, and determine the value of the physical variables of the model;

[0031] A grid unit wet and dry state judgment marking module is used to confirm the wet and dry change state of the grid unit after the numerical mode integration step is completed; when the grid unit changes from wet to dry, if the grid unit is a dry grid unit, maskCell (iCell) is marked as 0, and the next grid unit is judged after marking; if the grid unit is a wet grid unit, it is judged according to the wet grid unit judgment strategy, and the marking is performed after the judgment is completed; when the grid unit changes from dry to wet, if the grid unit is a wet grid unit, maskCell (iCell) is marked as 1, and the next grid unit is judged after marking; if the grid unit is a dry grid unit, it is judged according to the dry grid unit judgment strategy, and the marking is performed after the judgment is completed;

[0032] The final dry and wet state acquisition module of the grid unit is used to cycle the numerical model integration within the set simulation time, update the dry and wet state of the grid unit, and output the final dry and wet state of the grid unit in the simulation area until the simulation is completed.

[0033] As a preferred solution of a storm surge floodplain algorithm processing device based on SCVT unstructured grid, in the index strategy determination module, the index strategy of the adjacent grid cells of the grid cell is: for the iCell grid cell, the indexes of its adjacent grids are cellsOnCell(1,iCell), cellsOnCell(2,iCell)...cellsOnCell(nCOC,iCell);

[0034] The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell);

[0035] The indexing strategy for two adjacent grid cells of the grid edge is as follows: for the iEdge-th edge, the indices of its left and right adjacent grid cells are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges), respectively.

[0036] As a preferred solution of a storm surge overland flooding algorithm processing device based on SCVT unstructured grid, in the model physical variable definition module, during the process of defining the model physical variables, the model physical variables include storm surge water level rise depth, sea level water depth, total water depth, sea current velocity, and the distance between the centers of two adjacent grids.

[0037] The marking positions of the model physical variables in the grid cells are as follows: the model material variables of the storm surge water level rise depth, sea level water depth, and total water depth are set at the center positions of the grid cells; the model physical variable of the sea current velocity is set on the grid edge and the direction is perpendicular to the grid edge.

[0038] As a preferred solution of a storm surge overland flooding algorithm processing device based on SCVT unstructured grid, in the initial dry-wet state marking module, when the numerical model is initialized and the dry-wet states of the grid cells and grid edges are marked respectively, a grid cell without seawater is in the "dry" state, and a grid cell with seawater is in the "wet" state; maskCell(nCells) is used to mark the dry-wet state of the grid cells, and maskEdge(nEdges) is used to mark the dry-wet state of the grid edges, with the wet state being 1 and the dry state being 0.

[0039] As a preferred solution of a storm surge overland flooding algorithm processing device based on SCVT unstructured grid, in the grid cell dry-wet state judgment and marking module, when the unit grid is a wet grid cell, during the process of judging according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is as follows: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge water level rise h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0 and the flow velocity u(eoc) is 0.

[0040] When the unit grid is a dry grid cell, in the process of judging according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is: for the dry grid cell iCell, initialize the temporary counting variable count to 0, the temporary accumulation variable temp to 0, determine all adjacent grid cells of the dry grid cell iCell according to the index strategy of the adjacent grid cells of the grid cell, and for the j-th adjacent grid cell, calculate the water level difference deltaH; if deltaH>hMin, then add 1 to the temporary counting variable count, add deltaH to the temporary accumulation variable temp, and mark the grid edge dry and wet state maskEdge(eoc) as 1; when nCOC adjacent grid cells are determined, if count>0, mark the dry and wet state maskCell(iCell) of the dry grid cell iCell as 1.

[0041] The present invention has the following advantages: the simulation area is grid-divided according to the SCVT unstructured grid, and all the grid cells and grid edges in the simulation area are numbered; the index strategy of the adjacent grid cells of the grid cell, the index strategy of the grid edge corresponding to the grid cell and the index strategy of the two adjacent grid cells of the grid edge are respectively determined; the model physical variables are defined, and the marking positions of the model physical variables in the grid cells are set; when the numerical mode is initialized, the grid cells and grid edges are respectively marked for dry and wet states; the numerical mode is integrated according to the set time step, and the influence of the set factors on the seawater is calculated by the integration step to determine the value of the model physical variables; after the numerical mode integration step is completed, the dry and wet change state of the grid cell is confirmed; when the grid cell is subjected to the When the state changes from wet to dry, if the grid cell is a dry grid cell, maskCell (iCell) is marked as 0, and the next grid cell is judged after marking; if the grid cell is a wet grid cell, it is judged according to the wet grid cell judgment strategy, and the marking is performed after the judgment is completed; when the grid cell changes from dry to wet, if the grid cell is a wet grid cell, maskCell (iCell) is marked as 1, and the next grid cell is judged after marking; if the grid cell is a dry grid cell, it is judged according to the dry grid cell judgment strategy, and the marking is performed after the judgment is completed; the numerical model integration is cycled within the set simulation time, and the grid cell wet and dry states are updated until the simulation ends, and the final wet and dry states of the grid cells in the simulation area are output. The present invention applies SCVT unstructured grids to the wave numerical model, and uses the upwind format to apply the unstructured grids to the wave geographic space advection, so that the current storm surge model based on SCVT grids can be applied to floodplain simulation and forecasting, broadening and improving the functions of the current such models. At the same time, compared with the floodplain algorithm based on equal longitude and latitude grids and triangular grids, it has the function of local encryption and the calculation is more stable, making it more suitable for storm surge floodplain simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the drawings required for the implementation methods or the prior art descriptions are briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0043] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0044] Figure 1 A schematic diagram of a storm surge floodplain algorithm flow based on SCVT unstructured grid provided in Example 1 of the present invention;

[0045] Figure 2 A schematic diagram of SCVT grid variable distribution in a storm surge floodplain algorithm based on SCVT unstructured grid provided in Example 1 of the present invention;

[0046] Figure 3 A schematic diagram of the architecture of a storm surge floodplain algorithm processing device based on SCVT unstructured grid provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0047] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Example 1

[0049] See also Figure 1 Embodiment 1 of the present invention provides a storm surge floodplain algorithm based on SCVT unstructured grid, including:

[0050] S1. Divide the simulation area into grids according to the SCVT unstructured grid, and number all grid cells and grid edges in the simulation area;

[0051] S2, respectively determining the indexing strategy of the adjacent grid cells of the grid cell, the indexing strategy of the grid edge corresponding to the grid cell, and the indexing strategy of the two adjacent grid cells of the grid edge;

[0052] S3, defining model physical variables, and setting the marking positions of the model physical variables in the grid units;

[0053] S4, when the numerical mode is initialized, the grid cells and grid edges are marked for dry and wet states respectively;

[0054] S5, integrating the numerical model according to the set time step, calculating the influence of the set factors on the seawater through the integration step, and determining the values ​​of the physical variables of the model;

[0055] S6. After the numerical model integration is completed in one step, the wet-dry change state of the grid cell is confirmed; when the grid cell changes from wet to dry, if the grid cell is a dry grid cell, maskCell(iCell) is marked as 0, and the next grid cell is judged after marking; if the grid cell is a wet grid cell, it is judged according to the wet grid cell judgment strategy, and marked after the judgment is completed; when the grid cell changes from dry to wet, if the grid cell is a wet grid cell, maskCell(iCell) is marked as 1, and the next grid cell is judged after marking; if the grid cell is a dry grid cell, it is judged according to the dry grid cell judgment strategy, and marked after the judgment is completed;

[0056] S7, looping the numerical model integration within the set simulation time, and updating the dry and wet states of the grid units until the simulation is finished, and outputting the final dry and wet states of the grid units in the simulation area.

[0057] In this embodiment, in step S1, the simulation area is meshed according to the SCVT unstructured grid, and all mesh cells and mesh edges in the simulation area are numbered;

[0058] Specifically, all grid cells in the simulation area have unique numbers, represented by the subscript iCell, numbered 1, 2...nCells; each grid cell has nEOC edges and nCOC adjacent grids, and nEOC and nCOC are generally 6; all grid edges in the simulation area have unique numbers, represented by the subscript iEdge, numbered 1, 2...nEdges; each edge has two adjacent grid cells on the left and right.

[0059] In this embodiment, in step S2, the index strategy of the adjacent grid cells of the grid cell is: for the iCell th grid cell, the indexes of its adjacent grid cells are cellsOnCell(1, iCell), cellsOnCell(2, iCell) ... cellsOnCell(nCOC, iCell);

[0060] The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell);

[0061] The index strategy of the two adjacent grid cells of the grid edge is: for the iEdgeth edge, the indexes of the two adjacent grid cells on the left and right are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges) respectively.

[0062] In this embodiment, in step S3, in the process of defining the model physical variables, the model physical variables include storm surge depth, sea level depth, total water depth, current velocity, and the distance between two adjacent grid centers;

[0063] The marking positions of the model physical variables in the grid units are as follows: the storm surge depth, sea level depth, and total water depth model material variables are set at the center of the grid unit; the ocean current velocity model physical variables are set at the grid edge, and the direction is perpendicular to the grid edge.

[0064] Specifically, Figure 2 As shown in the figure, h represents the storm surge water, H represents the sea level water depth, ht=h+H represents the total water depth, and the dimensions of h, H and ht variables are nCells, distributed at the center of each grid cell. u represents the ocean current speed, with a dimension of nEdges, located at the edge of the grid, and the direction is perpendicular to the grid edge. dcEdge represents the distance between the centers of two adjacent grids at the grid edge, with a dimension of nEdges.

[0065] In this embodiment, in step S4, when the numerical mode is initialized, in the process of marking the dry and wet states of the grid cells and grid edges respectively, the grid cells without seawater are in a "dry" state, and the grid cells with seawater are in a "wet" state; maskCell (nCells) is used to mark the dry and wet states of the grid cells, and maskEdge (nEdges) is used to mark the dry and wet states of the grid edges, the wet state is 1, and the dry state is 0.

[0066] Specifically, for the iCell-th grid cell, if its total water depth ht(iCell) ≤ 0, then maskCell(iCell) = 0, indicating a dry state; otherwise, maskCell(iCell) = 1, indicating a wet state. Traverse all grid edges. For the iEdge-th grid edge, if the maskCells of its two adjacent grid cells are both 1, that is, both are wet grids, then maskEdge(iEdge) = 1, indicating a wet state; otherwise, maskEdge(iEdge) = 0, indicating a dry state. During the numerical model simulation, due to the change of ht, the values of maskCell and maskEdge may both change, especially for the grids near the coast.

[0067] In this embodiment, in step S5, numerical model integration is performed according to a set time step. By calculating the integral steps, the influence of set factors on seawater is calculated to determine the values of the model physical variables.

[0068] Among them, the set factors include atmospheric wind stress, atmospheric pressure, astronomical tide, bottom friction, water level gradient force, gravity, Coriolis force and other factors.

[0069] In this embodiment, in step S6, after one step of the numerical model integration is completed, the dry-wet change state of the grid cells is confirmed; when a grid cell changes from a wet state to a dry state, if the grid cell is a dry grid cell, then mark maskCell(iCell) as 0, and after marking, judge the next grid cell; if the grid cell is a wet grid cell, then judge according to the wet grid cell judgment strategy, and perform marking after the judgment is completed.

[0070] Among them, when the unit grid is a wet grid cell, during the judgment according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge increment h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0, and the flow velocity u(eoc) is 0.

[0071] Specifically, due to the receding of the seawater, the grid cells that were originally occupied by seawater may become dry, that is, the process of the grid changing from a wet state to a dry state. After each step of the numerical model integration is completed, all grid cells are traversed. For the iCell grid, if it is a dry grid, that is, maskCell(iCell) is 0, skip this grid cell and move on to the next grid cell; otherwise, if it is a wet grid, continue to the next step. For the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge increment h(iCell) = 0; for the nEOC edges corresponding to the grid, maskEdge(eoc) is marked as 0, and the flow velocity u(eoc) = 0, where eoc = edgesOnCell(j, iCell), j = 1, 2... nEOC. hMin is a critical value, generally 0.1 m.

[0072] Pseudocode:

[0073] “for iCell = 1, nCells:

[0074] if maskCell(iCell) = 1:

[0075] if ht(iCell) < hMin:

[0076] maskCell(iCell) = 0

[0077] h(iCell) = 0

[0078] for j = 1, nEOC:

[0079] eoc = edgesOnCell(j, iCell)

[0080] u(eoc) = 0

[0081] maskEdge(eoc) = 0”.

[0082] In this embodiment, in step S6, it further includes: after one step of the numerical model integration is completed, confirm the dry-wet change state of the grid cells; when the grid cells change from a dry state to a wet state, if the grid cells are wet grid cells, then mark maskCell(iCell) as 1, and after marking, judge the next grid cell; if the grid cells are dry grid cells, then judge according to the dry grid cell judgment strategy, and after the judgment is completed, mark.

[0083] Among them, when the unit grid is a dry grid cell, in the process of judging according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is: for the dry grid cell iCell, initialize the temporary counting variable count to 0, the temporary accumulation variable temp to 0, and determine all adjacent grid cells of the dry grid cell iCell according to the index strategy of the adjacent grid cells of the grid cell, and for the j-th adjacent grid cell, calculate the water level difference deltaH; if deltaH>hMin, then the temporary counting variable count is increased by 1, deltaH is added to the temporary accumulation variable temp, and the grid edge dry and wet state maskEdge(eoc) is marked as 1; when nCOC adjacent grid cells are determined, if count>0, then the dry and wet state maskCell(iCell) of the dry grid cell iCell is marked as 1.

[0084] Specifically, due to the invasion of seawater, the original land grid may become wet, that is, the grid changes from a dry state to a wet state. After each step of numerical model integration is completed, all grid cells are traversed. For the iCell grid cell, if it is a wet grid, that is, maskCell(iCell) is 1, skip the grid cell and enter the next grid cell; conversely, if it is a dry grid, continue to the next link. For the dry grid cell iCell, initialize the temporary count variable count = 0, the temporary accumulation variable temp = 0, traverse all its adjacent grid cells (adjacent grid cell index coc = cellsOnCll(j,iCell), corresponding grid edge index eoc = edgesOnCell(j,iCell), j = 1,2…nCOC), for the jth adjacent grid, calculate the water level difference deltaH = ht(coc)-ht(iCell). If deltaH>hMin, the temporary count variable count is increased by 1, deltaH is added to the temporary cumulative variable temp, the speed of the corresponding grid edge u(eoc) = -dt*g*deltaH / dcEdge(eoc), and the grid edge wet and dry state maskEdge(eoc) = 1. When the traversal of nCOC adjacent grid cells is completed, if count>0, the wet and dry state of the grid cell maskCell(iCell) = 1, h(iCell) = temp / (count+1).

[0085] pseudocode:

[0086] “for iCell=1,nCells:

[0087] if maskCell(iCell)=0:

[0088] count=0

[0089] temp=0

[0090] for j=1,nCOC:

[0091] coc = cellsOnCell(j,iCell)

[0092] eoc=edgesOnCell(j,iCell)

[0093] deltaH=ht(coc)–ht(iCell)

[0094] if deltaH>hMin:

[0095] count=count+1

[0096] temp=temp+deltaH

[0097] maskEdge(eoc)=1

[0098] u(eoc)=-dt*g*deltaH / dcEdge(eoc)

[0099] if count>0:

[0100] maskCell(iCell)=1

[0101] h(iCell)=temp / (count+1)”.

[0102] In this embodiment, in step S7, the numerical model integration is circulated within the set simulation time, and the dry and wet states of the grid units are updated until the simulation is completed, and the final dry and wet states of the grid units in the simulation area are output.

[0103] Specifically, the numerical model starts the integral forecast from time 0, and the numerical model integration is cyclically performed within the set simulation time, with each forward forecast time step being dt, until the simulation ends.

[0104] In summary, the present invention divides the simulation area into grids according to the SCVT unstructured grid, and numbers all the grid cells and grid edges in the simulation area; respectively determines the index strategy of the adjacent grid cells of the grid cell, the index strategy of the grid edge corresponding to the grid cell, and the index strategy of the two adjacent grid cells of the grid edge; defines the model physical variables, and sets the marking position of the model physical variables in the grid cells; when the numerical mode is initialized, the grid cells and grid edges are respectively marked for dry and wet states; the numerical mode is integrated according to the set time step, and the influence of the set factors on the seawater is calculated through the integration step to determine the value of the model physical variables; after the numerical mode integration step is completed, the dry and wet change state of the grid cell is confirmed; when the grid cell changes from wet to dry, the grid cell changes from wet to dry; and when the grid cell changes from wet to dry, the grid cell changes from wet to dry. When the state changes from dry to wet, if the grid cell is a dry grid cell, maskCell (iCell) is marked as 0, and the next grid cell is judged after marking; if the grid cell is a wet grid cell, it is judged according to the wet grid cell judgment strategy, and the marking is performed after the judgment is completed; when the grid cell changes from dry to wet, if the grid cell is a wet grid cell, maskCell (iCell) is marked as 1, and the next grid cell is judged after marking; if the grid cell is a dry grid cell, it is judged according to the dry grid cell judgment strategy, and the marking is performed after the judgment is completed; the numerical model integration is cycled within the set simulation time, and the dry and wet states of the grid cells are updated until the simulation ends, and the final dry and wet states of the grid cells in the simulation area are output. The present invention applies SCVT unstructured grids to the wave numerical model, and uses the upwind format to apply the unstructured grids to the wave geographic space advection, so that the current storm surge model based on SCVT grids can be applied to floodplain simulation and forecasting, broadening and improving the functions of the current such models. At the same time, compared with the floodplain algorithm based on equal longitude and latitude grids and triangular grids, it has the function of local encryption and the calculation is more stable, making it more suitable for storm surge floodplain simulation.

[0105] It should be noted that the method of the embodiment of the present disclosure can be performed by a single device, such as a computer or a server. The method of the present embodiment can also be applied in a distributed scenario and completed by multiple devices cooperating with each other. In the case of such a distributed scenario, one of the multiple devices can only perform one or more steps in the method of the embodiment of the present disclosure, and the multiple devices will interact with each other to complete the described method.

[0106] It should be noted that the above describes some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0107] Example 2

[0108] See also Figure 3 Embodiment 2 of the present invention provides a storm surge floodplain algorithm processing device based on SCVT unstructured grid, comprising:

[0109] The grid division and numbering module 001 is used to grid the simulation area according to the SCVT unstructured grid and number all the grid cells and grid edges in the simulation area;

[0110] An index strategy determination module 002, used to respectively determine the index strategy of the adjacent grid cells of the grid cell, the index strategy of the grid edge corresponding to the grid cell, and the index strategy of two adjacent grid cells of the grid edge;

[0111] A model physical variable definition module 003 is used to define the model physical variables and set the marking positions of the model physical variables in the grid units;

[0112] The initial dry-wet state marking module 004 is used to mark the dry-wet state of the grid cells and grid edges respectively when the numerical mode is initialized;

[0113] The numerical model integration module 005 is used to perform numerical model integration according to a set time step, calculate the influence of the set factors on the seawater through the integration step, and determine the value of the physical variable of the model;

[0114] The grid unit wet and dry state judgment marking module 006 is used to confirm the wet and dry change state of the grid unit after the numerical mode integration step is completed; when the grid unit changes from wet to dry, if the grid unit is a dry grid unit, the maskCell (iCell) is marked as 0, and the next grid unit is judged after marking; if the grid unit is a wet grid unit, it is judged according to the wet grid unit judgment strategy, and the marking is performed after the judgment is completed; when the grid unit changes from dry to wet, if the grid unit is a wet grid unit, the maskCell (iCell) is marked as 1, and the next grid unit is judged after marking; if the grid unit is a dry grid unit, it is judged according to the dry grid unit judgment strategy, and the marking is performed after the judgment is completed;

[0115] The grid unit final wet and dry state acquisition module 007 is used to cycle the numerical model integration within the set simulation time, and update the wet and dry state of the grid unit until the simulation is completed, and output the final wet and dry state of the grid unit in the simulation area.

[0116] In this embodiment, in the index strategy determination module 002, the index strategy of the adjacent grid cells of the grid cell is: for the iCell th grid cell, the indexes of its adjacent grids are cellsOnCell(1, iCell), cellsOnCell(2, iCell) ... cellsOnCell(nCOC, iCell);

[0117] The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell);

[0118] The index strategy of the two adjacent grid cells of the grid edge is: for the iEdgeth edge, the indexes of the two adjacent grid cells on the left and right are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges) respectively.

[0119] In this embodiment, in the model physical variable definition module 003, in the process of defining the model physical variables, the model physical variables include storm surge water depth, sea level water depth, total water depth, current velocity and the distance between two adjacent grid centers at the grid edge;

[0120] The marking positions of the model physical variables in the grid units are as follows: the storm surge depth, sea level depth, and total water depth model material variables are set at the center of the grid unit; the ocean current velocity model physical variables are set at the grid edge, and the direction is perpendicular to the grid edge.

[0121] In this embodiment, in the initial dry and wet state marking module 004, when the numerical mode is initialized, in the process of marking the dry and wet states of the grid cells and grid edges respectively, the grid cells without seawater are in a "dry" state, and the grid cells with seawater are in a "wet" state; maskCell (nCells) is used to mark the dry and wet states of the grid cells, and maskEdge (nEdges) is used to mark the dry and wet states of the grid edges, the wet state is 1, and the dry state is 0.

[0122] In this embodiment, in the wet / dry state judgment and marking module 006 of the grid cell, when the cell grid is a wet grid cell, during the judgment according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is as follows: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge water level rise h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0, and the flow velocity u(eoc) is 0.

[0123] When the cell grid is a dry grid cell, during the judgment according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is as follows: for the dry grid cell iCell, initialize the temporary counting variable count to 0 and the temporary accumulation variable temp to 0. Determine all adjacent grid cells of the dry grid cell iCell according to the index strategy of the adjacent grid cells of the grid cell. For the j-th adjacent grid cell, calculate the water level difference deltaH; if deltaH > hMin, then increment the temporary counting variable count by 1, add deltaH to the temporary accumulation variable temp, and mark the wet / dry state of the grid edge maskEdge(eoc) as 1; when the determination of the nCOC adjacent grid cells is completed, if count > 0, then mark the wet / dry state maskCell(iCell) of the dry grid cell iCell as 1.

[0124] It should be noted that for the information interaction, execution process, etc. between the above-mentioned system modules / units, since they are based on the same concept as the method embodiment in Embodiment 1 of this application, the technical effects brought by them are the same as those of the method embodiment of this application. For the specific content, reference can be made to the description in the method embodiment shown above in this application, and details will not be elaborated here.

[0125] Embodiment 3

[0126] Embodiment 3 of the present invention provides a non-transitory computer-readable storage medium, in which a program code of a storm surge overland flow algorithm based on an SCVT unstructured grid is stored. The program code includes instructions for executing a storm surge overland flow algorithm based on an SCVT unstructured grid in Embodiment 1 or any possible implementation thereof.

[0127] The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrating one or more available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid-state drive (SSD)).

[0128] Example 4

[0129] Embodiment 4 of the present invention provides an electronic device, including: a memory and a processor;

[0130] The processor and the memory communicate with each other via a bus; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute a storm surge floodplain algorithm based on an SCVT unstructured grid in Example 1 or any possible implementation thereof.

[0131] Specifically, the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor implemented by reading software codes stored in a memory. The memory can be integrated in the processor or can be located outside the processor and exist independently.

[0132] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center.

[0133] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0134] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A storm surge floodplain algorithm based on SCVT unstructured grid, characterized in that: Including: Meshing the simulation area according to the SCVT unstructured grid, and numbering all grid cells and grid edges within the simulation area; Respectively determining the indexing strategy for adjacent grid cells of a grid cell, the indexing strategy for the grid edge corresponding to a grid cell, and the indexing strategy for two adjacent grid cells of a grid edge; Defining the model physical variables and setting the marked positions of the model physical variables in the grid cells; During the initialization of the numerical model, marking the wet / dry states of grid cells and grid edges respectively; Performing numerical model integration according to the set time step, calculating the influence of the seawater under the set factors through the integration step, and determining the values of the model physical variables; After one step of the numerical model integration is completed, confirming the wet / dry change state of the grid cell; when the grid cell changes from wet to dry, if the grid cell is a dry grid cell, then mark maskCell(iCell) as 0, and after marking, judge the next grid cell; if the grid cell is a wet grid cell, then judge according to the wet grid cell judgment strategy, and perform marking after the judgment is completed; When the grid cell changes from dry to wet, if the grid cell is a wet grid cell, then mark maskCell(iCell) as 1, and after marking, judge the next grid cell; if the grid cell is a dry grid cell, then judge according to the dry grid cell judgment strategy, and perform marking after the judgment is completed; Performing cyclic numerical model integration within the set simulation time and updating the wet / dry states of grid cells until the simulation ends, and outputting the final wet / dry states of grid cells in the simulation area; During the process of defining the model physical variables, the model physical variables include the storm surge water level rise depth, sea level water depth, total water depth, sea current velocity, and the distance between the centers of two adjacent grid cells of a grid edge; The marked positions of the model physical variables in the grid cells are: the storm surge water level rise depth, sea level water depth, and total water depth model material variables are set at the center positions of the grid cells; the sea current velocity model physical variable is set on the grid edge and the direction is perpendicular to the grid edge; During the initialization of the numerical model, during the process of respectively marking the wet / dry states of grid cells and grid edges, a grid cell without seawater is in the "dry" state, and a grid cell with seawater is in the "wet" state; the maskCell(nCells) is used to mark the wet / dry state of the grid cell, and the maskEdge(nEdges) is used to mark the wet / dry state of the grid edge, with the wet state being 1 and the dry state being 0; When the unit grid is a wet grid cell, during the process of judging according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge water level rise h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0, and the flow velocity u(eoc) is 0; When the unit grid is a dry grid cell, in the process of judging according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is: for the dry grid cell iCell, initialize the temporary counting variable count to 0, the temporary accumulation variable temp to 0, determine all adjacent grid cells of the dry grid cell iCell according to the index strategy of the adjacent grid cells of the grid cell, and for the j-th adjacent grid cell, calculate the water level difference deltaH; if deltaH>hMin, then add 1 to the temporary counting variable count, add deltaH to the temporary accumulation variable temp, and mark the grid edge dry and wet state maskEdge(eoc) as 1; when nCOC adjacent grid cells are determined, if count>0, mark the dry and wet state maskCell(iCell) of the dry grid cell iCell as 1.

2. A storm surge floodplain algorithm based on SCVT unstructured grid according to claim 1, characterized in that: The index strategy of the adjacent grid cells of the grid cell is: for the iCell th grid cell, the indexes of its adjacent grids are cellsOnCell(1, iCell), cellsOnCell(2, iCell) ... cellsOnCell(nCOC, iCell); The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell); The index strategy of the two adjacent grid cells of the grid edge is: for the iEdgeth edge, the indexes of the two adjacent grid cells on the left and right are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges) respectively.

3. A storm surge floodplain algorithm processing device based on SCVT unstructured grid, using the storm surge floodplain algorithm based on SCVT unstructured grid as described in claims 1-2 above, characterized in that: include: The meshing and numbering module is used to mesh the simulation area according to the SCVT unstructured grid and number all the grid cells and grid edges in the simulation area; An index strategy determination module, used to respectively determine the index strategy of the adjacent grid cells of the grid cell, the index strategy of the grid edge corresponding to the grid cell, and the index strategy of two adjacent grid cells of the grid edge; A model physical variable definition module, used to define the model physical variables and set the marking positions of the model physical variables in the grid units; An initial dry-wet state marking module is used to mark the dry-wet state of the grid cells and grid edges respectively when the numerical mode is initialized; A numerical model integration module is used to perform numerical model integration according to a set time step, calculate the influence of set factors on seawater through the integration step, and determine the value of the physical variables of the model; A grid cell wet / dry state judgment and marking module is used to confirm the wet / dry change state of the grid cell after the numerical mode integration step is completed; when the grid cell changes from wet to dry, if the grid cell is a dry grid cell, maskCell(iCell) is marked as 0, and after marking, the next grid cell is judged; if the grid cell is a wet grid cell, it is judged according to the wet grid cell judgment strategy, and marked after the judgment is completed; When the grid cell changes from dry to wet, if the grid cell is a wet grid cell, maskCell(iCell) is marked as 1, and the next grid cell is judged after marking; if the grid cell is a dry grid cell, it is judged according to the dry grid cell judgment strategy, and marked after the judgment is completed; The final dry and wet state acquisition module of the grid unit is used to cycle the numerical model integration within the set simulation time, update the dry and wet state of the grid unit, and output the final dry and wet state of the grid unit in the simulation area until the simulation is completed.

4. The storm surge floodplain algorithm processing device based on SCVT unstructured grid according to claim 3 is characterized in that: In the index strategy determination module, the index strategy of the adjacent grid cells of the grid cell is: for the iCell th grid cell, the indexes of its adjacent grids are cellsOnCell(1, iCell), cellsOnCell(2, iCell) ... cellsOnCell(nCOC, iCell); The index strategy of the grid edges corresponding to the grid cells is: for the iCell th grid cell, the indexes of the grid edges constituting the grid cell are edgesOnCell(1,iCell), edgesOnCell(2,iCell)...edgesOnCell(nEOC,iCell); The index strategy of the two adjacent grid cells of the grid edge is: for the iEdgeth edge, the indexes of the two adjacent grid cells on the left and right are cellsOnEdge(1, iEdges) and cellsOnEdge(2, iEdges) respectively.

5. The storm surge floodplain algorithm processing device based on SCVT unstructured grid according to claim 4 is characterized in that: In the model physical variable definition module, in the process of defining the model physical variables, the model physical variables include storm surge depth, sea level depth, total water depth, current velocity and the distance between two adjacent grid centers at the grid edge; The marking positions of the model physical variables in the grid units are as follows: the storm surge depth, sea level depth, and total water depth model material variables are set at the center of the grid unit; the ocean current velocity model physical variables are set at the grid edge, and the direction is perpendicular to the grid edge.

6. The storm surge floodplain algorithm processing device based on SCVT unstructured grid according to claim 5 is characterized in that: In the initial dry and wet state marking module, when the numerical mode is initialized, in the process of marking the dry and wet states of the grid cells and grid edges respectively, the grid cells without seawater are in a "dry" state, and the grid cells with seawater are in a "wet" state; maskCell (nCells) is used to mark the dry and wet states of the grid cells, and maskEdge (nEdges) is used to mark the dry and wet states of the grid edges, with the wet state being 1 and the dry state being 0.

7. The storm surge floodplain algorithm processing device based on SCVT unstructured grid according to claim 6 is characterized in that: In the wet / dry state judgment and marking module of the grid cell, when the cell grid is a wet grid cell, during the judgment process according to the wet grid cell judgment strategy, the wet grid cell judgment strategy is as follows: for the wet grid cell iCell, if its total water depth ht(iCell) < hMin, then maskCell(iCell) is marked from 1 to 0; the storm surge water level rise h(iCell) is 0; for the nEOC edges corresponding to the wet grid cell, maskEdge(eoc) is marked as 0 and the flow velocity u(eoc) is 0. When the cell grid is a dry grid cell, during the judgment process according to the dry grid cell judgment strategy, the dry grid cell judgment strategy is as follows: for the dry grid cell iCell, initialize the temporary counting variable count to 0 and the temporary accumulation variable temp to 0. Determine all adjacent grid cells of the dry grid cell iCell according to the adjacent grid cell indexing strategy of the grid cell. For the j-th adjacent grid cell, calculate the water level difference deltaH; if deltaH > hMin, then increment the temporary counting variable count by 1, add deltaH to the temporary accumulation variable temp, and mark the wet / dry state of the grid edge maskEdge(eoc) as 1; when the determination of the nCOC adjacent grid cells is completed, if count > 0, then mark the wet / dry state maskCell(iCell) of the dry grid cell iCell as 1.

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