Physical field transmission method for landslide surge multi-scale model based on dynamic conversion domain

Abstract

The application provides a landslide surge multi-scale model physical field transmission method based on a dynamic conversion domain, and contains the following steps: step 1: traversing a landslide surge near-field calculation SPH landslide particle to judge whether the landslide stops; step 2: if the landslide movement stops, then traversing the SPH water body particle; step 3: calculating the model grid interval and node position to generate a dynamic conversion domain grid; step 4: interpolating and transmitting the near-field surge physical quantity carried by the SPH water body particle to the dynamic conversion domain grid node; step 5: updating the landslide surge far-field propagation FDM model topographic elevation information; step 6: performing the far-field calculation of the landslide surge. The application of the technical scheme can realize the information transmission between the SPH model of the surge near-field calculation and the FDM model of the far-field calculation, which is a key technology of the multi-scale analysis method of the reservoir area landslide surge, and provides technical support for the prevention and control of the reservoir area surge disaster.

Description

Technical Field

[0001] This invention relates to the field of computational fluid dynamics, and in particular to a method for transferring physical fields in a multi-scale model of landslide surge based on a dynamic transformation domain. Background Technology

[0002] Smoothed Particle Hydrodynamics (SPH) is a meshless Lagrangian method widely used in the study of solid mechanics and fluid dynamics. In the near-field generation of landslide surges, SPH can effectively simulate large deformations and multiphase coupling. However, the large computational domain of far-field surge propagation limits its application. The Finite Difference Method (FDM) transforms nonlinear ordinary differential equations or partial differential equations into linear equations for solution. It is a numerical technique that approximates analytical solutions to differential equations using finite difference derivatives. The introduction of parallel computing and other techniques can significantly improve the computational efficiency of the algorithm, leading to its widespread application in long-distance surge propagation problems such as tsunamis and landslide surges. In landslide surge simulations, different models are needed for the near-field simulation of the surge generation zone and the far-field simulation of the surge propagation zone; otherwise, a balance between computational accuracy and efficiency cannot be achieved. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a physical field transfer method for a multi-scale model of landslide surge based on a dynamic transformation domain. This method realizes the key technology of information transfer between the SPH model for near-field calculation of surge and the FDM model for far-field calculation of surge, providing technical support for the prevention and control of surge disasters in reservoir areas.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a physical field transfer method for a multi-scale model of landslide surge based on a dynamic transformation domain, comprising the following steps:

[0005] Step 1: Calculate the SPH (Surface Heating Principle) of landslide particles in the near field of the landslide surge to determine whether the landslide has stopped;

[0006] Step 2: If the landslide stops, then trace all the SPH water particles and mark the water particles with non-zero velocities. The area covered by this marking is the near-field surge wave propagation range.

[0007] Step 3: Generate a dynamic transformation domain mesh based on the near-field surge propagation range, far-field calculation model mesh spacing, and node positions;

[0008] Step 4: Interpolate the near-field surge physical quantities carried by SPH water particles and pass them to the dynamic transformation domain grid nodes; interpolate the landslide accumulation distribution information carried by SPH soil particles and pass it to the dynamic transformation domain grid nodes.

[0009] Step 5: Update the landslide surge far-field propagation FDM model topographic elevation information using the accumulation distribution information carried by the grid nodes in the dynamic transformation domain;

[0010] Step 6: Use the near-field surge physical quantities carried by the grid nodes of the dynamic transformation domain as the initial conditions for the calculation of the far-field propagation FDM model of landslide surge, and perform far-field calculation of landslide surge.

[0011] In a preferred embodiment, step 1 calculates the absolute velocity of all SPH landslide particles by traversing all of them, and the absolute velocity of the i-th SPH particle is vsmod. i The expression is as follows:

[0012]

[0013] Among them, vs i (1) vs i (2) These are the velocity values ​​of the i-th landslide SPH particle in the x and y directions, respectively; assuming the initial value of the maximum value vsmod_max is -1, compare vsmod_max for each landslide SPH particle. i If vsmod_max is the same as vsmod i >vsmod_max will then set vsmod i The magnitude is assigned to vsmod_max; after the traversal is completed, first, if vsmod_max < 0, the program will report an error, indicating that the calculation of the maximum absolute velocity of the particles is incorrect; then, if vsmod_max > 0 and vsmod_max - 0 ≤ 10, the program will further check if vsmod_max > 0 and vsmod_max - 0 ≤ 10. -5 If the landslide particles are in a stopped state, then it is considered that the landslide particles are in a stopped state at this time; otherwise, the landslide has not stopped, and the next time step is entered to update the particle information and continue to determine whether the landslide has stopped.

[0014] In a preferred embodiment, step 2 iterates through all SPH water particles to calculate their absolute velocities, and for the i-th SPH water particle, the absolute velocity is vwmod. i The expression is as follows:

[0015]

[0016] Among them, vw i (1) vw i (2) are the velocity values ​​of the i-th SPH particle in the water body in the x and y directions, respectively; if vwmod i -0≤10 -5Then, the i-th water body SPH particle is marked as a water body particle with a flow velocity of non-zero; the propagation range of the near-field surge is determined based on the maximum (xwmax, ywmax) and minimum (xwmin, ywmin) x and y coordinate values ​​of the water body particles with a flow velocity of non-zero.

[0017] In a preferred embodiment, the dynamic transformation domain mesh in step 3 is generated based on the near-field propagation range of the landslide surge, the grid spacing of the remotely calculated FDM model, and the node locations; it includes the following steps:

[0018] Step 31: Based on the maximum x and y coordinate values ​​"xwmax, ywmax" and minimum xwmin, ywmin" of the water particles with non-zero flow velocity, which is the propagation range of the near-field surge, delineate the corresponding rectangular influence area and determine the coordinate values ​​of four vertices TZ1(x,y), TZ2(x,y), TZ3(x,y), and TZ4(x,y), where TZ1 corresponds to the point "xwmin, ywmin" and TZ4 corresponds to the point "xwmax, ywmax".

[0019] Step 32: Based on the coordinates of the four vertices of the rectangular influence region, determine the far-field FDM model elements contained within the rectangular influence region; for any FDM model element, its four nodes are EP1, EP2, EP3, and EP4, if and only if

[0020]

[0021] When established, the FDM model element is located within the rectangular influence area, and the element number is marked.

[0022] Step 33: Further consider the FDM model elements cut by the boundary line of the affected domain. First, calculate the center point coordinates (cent) of each element. i (x,y), for any element FDM i ,have:

[0023]

[0024] Using the edge vectors of the rectangular influence region, calculate the distance DIST from any cell to the edge vector. i First, calculate the four edge vectors of the rectangular influence region:

[0025]

[0026] Calculate the minimum distance dist_min from the center point of each element to the boundary of the rectangular influence area. i :

[0027]

[0028] Based on the far-field calculation model, the minimum distance dist_min between the grid spacing size ediag and the boundary of the rectangular influence area of ​​each cell center point is used. i The FDM model elements that are cut by the boundary line of the affected domain are determined based on the following criteria:

[0029] dist_min i <ediag (7)

[0030] If the above formula is satisfied, the FDM model element is cut by the boundary line of the influence domain and the element number is marked. In summary, the dynamic transformation domain mesh is determined, which consists of the far-field FDM model elements contained in the rectangular influence region and the FDM model elements cut by the boundary line of the influence domain.

[0031] In a preferred embodiment, step 4 interpolates the near-field surge physical quantities carried by SPH water particles and transmits them to the dynamic transformation domain grid nodes, and interpolates the landslide deposit distribution information carried by SPH soil particles and transmits it to the dynamic transformation domain grid nodes; this includes the following steps:

[0032] Step 41: Traverse all SPH particles and determine the dynamic conversion domain grid in which they are located based on their coordinate values. Use cell_of_particle(:) and particle_in_cell(:) to store the dynamic conversion domain grid number corresponding to the particle and the number of SPH particles contained in each dynamic conversion domain grid, respectively.

[0033] Step 42: Traverse all dynamic transformation domain grids, interpolating the near-field surge physical quantities carried by SPH water particles and the landslide deposit distribution information carried by SPH soil particles to the dynamic transformation domain grid nodes; calculate the physical quantity values ​​interpolated from SPH particles to the grid nodes within the grid, using the following formula:

[0034]

[0035] Where, φ i It is the physical quantity value φ at node i of the dynamic transformation domain mesh. j It is the near-field swell physical quantity carried by SPH water particles j, d ij Let be the distance between node i and particle j, and m be a calculation parameter that can be set to 1.

[0036] In a preferred embodiment, step 5 updates the landslide surge far-field propagation FDM model topographic elevation information using the accumulation distribution information carried by the dynamic transformation domain grid nodes; wherein, the accumulation depth value dep carried by the dynamic transformation domain grid node i is... i Adding the z-direction value of the terrain coordinates of the original surge far-field propagation FDM model to obtain the updated FDM model terrain elevation information topo(z) is obtained. iThe calculation formula is as follows:

[0037] topo(z) i =topo(z) i +dep i (9)

[0038] Where i represents the i-th FDM model mesh node.

[0039] In a preferred embodiment, step 6 uses the near-field surge physical quantities carried by the nodes of the dynamic conversion domain grid as the initial conditions for calculating the far-field propagation FDM model of the landslide surge, and performs far-field calculation of the landslide surge. Since the dynamic conversion domain grid is established on the basis of the far-field propagation FDM model, the interpolation process can be directly completed according to the node information index. The near-field surge physical quantities transmitted include: velocity lists u(:) and v(:), water depth list h(:), and topographic information using the topographic height topol(:,:,:) formed after landslide triggering, considering the depth of the deposited mass. i .

[0040] Compared with existing technologies, this invention has the following advantages: Addressing the problem of needing to use different models for near-field simulation of the surge generation zone and far-field simulation of the surge propagation zone in landslide surge simulation calculations to achieve a balance between computational accuracy and efficiency, this invention proposes a physical field transfer method based on a dynamic transformation domain. This method realizes the key technology of multi-scale analysis of landslide surges in reservoir areas—the information transfer between the SPH model for near-field surge calculation and the FDM model for far-field surge calculation—providing technical support for the prevention and control of surge disasters in reservoir areas. Attached Figure Description

[0041] Figure 1 This is a flowchart of a preferred embodiment of the present invention.

[0042] Figure 2 This is a schematic diagram of the near-field generation and far-field propagation of landslide surge in the reservoir area, which is a preferred embodiment of the present invention.

[0043] Figure 3 A schematic diagram of the rectangular influence region of the preferred embodiment of the present invention, including the far-field FDM model unit, the FDM model unit cut by the boundary line of the influenced domain, and the dynamic transformation domain mesh.

[0044] Figure 4 This is a schematic diagram of an interpolation algorithm using velocity vector as an example, which is a preferred embodiment of the present invention. Detailed Implementation

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0046] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0047] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0048] This invention addresses the problem in landslide surge simulation calculations where different models are needed for near-field simulation of the surge generation zone and far-field simulation of the surge propagation zone to achieve a balance between computational accuracy and efficiency. It proposes a physical field transfer method based on a dynamic transformation domain, realizing information transfer between the SPH model for near-field surge calculation and the FDM model for far-field calculation—a key technology in multi-scale analysis of landslide surges in reservoir areas. This provides technical support for the prevention and control of surge disasters in reservoir areas. A detailed implementation flowchart is attached. Figure 1 As shown. It mainly includes the following 6 steps:

[0049] Step 1: Calculate the SPH (Surface Heating Principle) of landslide particles in the near field of the landslide surge to determine whether the landslide has stopped;

[0050] Step 2: If the landslide stops, then trace all the SPH water particles and mark the water particles with non-zero velocities. The area covered by this marking is the near-field surge wave propagation range.

[0051] Step 3: Generate a dynamic transformation domain mesh based on the near-field surge propagation range, far-field calculation model mesh spacing, and node positions;

[0052] Step 4: Interpolate the near-field surge physical quantities carried by SPH water particles and pass them to the dynamic transformation domain grid nodes; interpolate the landslide accumulation distribution information carried by SPH soil particles and pass it to the dynamic transformation domain grid nodes.

[0053] Step 5: Update the landslide surge far-field propagation FDM model topographic elevation information using the accumulation distribution information carried by the grid nodes in the dynamic transformation domain;

[0054] Step 6: Use the near-field surge physical quantities carried by the grid nodes of the dynamic transformation domain as the initial conditions for the calculation of the far-field propagation FDM model of landslide surge, and perform far-field calculation of landslide surge.

[0055] Select a real-world case study of a reservoir landslide and surge affecting a downstream dam (see schematic diagram for example). Figure 2In this case, a gravity dam is located more than ten kilometers downstream of the landslide trigger point. After the landslide surge is generated in the near field, it may propagate further downstream, affecting the safe operation of the dam. According to the methodology (… Figure 1 ) A detailed explanation will be provided:

[0056] Step 1: Calculate the absolute velocity (vsmod) of all SPH landslide particles in the near-field of the landslide surge to determine if the landslide has stopped. Calculate the absolute velocity of the i-th SPH particle. i The expression is as follows:

[0057]

[0058] Among them, vs i (1) vs i (2) These are the velocity values ​​of the i-th SPH particle in the x and y directions, respectively. Assuming the initial value of the maximum value vsmod_max is -1, vsmod is compared for each SPH particle in the landslide. i If vsmod_max is the same as vsmod i >vsmod_max will then set vsmod i The magnitude is assigned to `vsmod_max`. After traversal, the program first checks if `vsmod_max < 0`, then reports an error indicating an error in calculating the maximum absolute velocity of the particles. Further checks are performed if `vsmod_max > 0` and `vsmod_max - 0 ≤ 10`. -5 If the landslide is considered to have stopped, then all SPH landslide particles are considered to be in a stopped state. Otherwise, the landslide has not stopped, and the process proceeds to the next time step to update particle information and continue to determine whether the landslide has stopped.

[0059] Step 2: If the landslide stops, then trace all SPH water particles and mark those with non-zero velocities. The area covered by these particles is the near-field surge wave propagation range. The specific calculation method is as follows: Calculate the absolute velocity of all SPH water particles. For the i-th SPH water particle, the absolute velocity vwmod i The expression is as follows:

[0060]

[0061] Among them, vw i (1) vw i (2) These are the velocity values ​​of the i-th SPH particle in the water body in the x and y directions, respectively. If vwmod i -0≤10 -5The i-th water particle with SPH is then marked as a water particle with a flow velocity not equal to 0. The propagation range of the near-field surge is determined based on the maximum (xwmax, ywmax) and minimum (xwmin, ywmin) x and y coordinate values ​​of the water particles with a flow velocity not equal to 0.

[0062] Step 3: Generate a dynamic transformation domain mesh based on the near-field surge propagation range, far-field computational model mesh spacing, and node locations. This includes the following steps:

[0063] S3.1: Delineate the rectangular influence area of ​​the near-field surge, including the coverage area of ​​water particles with non-zero velocity. Based on the maximum (xwmax, ywmax) and minimum (xwmin, ywmin) x and y coordinates of water particles with non-zero velocity, i.e., the propagation range of the near-field surge, delineate the corresponding rectangular influence area and determine the coordinates of four vertices: TZ1(x,y), TZ2(x,y), TZ3(x,y), and TZ4(x,y), where TZ1 corresponds to point (xwmin, ywmin) and TZ4 corresponds to point (xwmax, ywmax).

[0064] S3.2: Determine the far-field FDM model elements completely contained within the rectangular influence region. Based on the coordinates of the four vertices of the rectangular influence region, determine the far-field FDM model elements contained within it. For any FDM model element, its four nodes are EP1, EP2, EP3, and EP4, respectively, if and only if...

[0065]

[0066] When established, the FDM model element is located within the rectangular influence area, and the element number is marked.

[0067] S3.3: Determine the FDM model elements cut by the boundary lines of the affected domain, and thus determine the dynamic transformation domain mesh. First, calculate the center point coordinates (cent) of each element. i (x,y), for any element FDM i ,have:

[0068]

[0069] Using the edge vectors of the rectangular influence region, calculate the distance DIST from any cell to the edge vector. i First, calculate the four edge vectors of the rectangular influence region:

[0070]

[0071] Calculate the minimum distance dist_min from the center point of each element to the boundary of the rectangular influence area. i :

[0072]

[0073] Based on the far-field calculation model, the minimum distance dist_min between the grid spacing size ediag and the boundary of the rectangular influence area of ​​each cell center point is used. i The FDM model elements that are cut by the boundary line of the affected domain are determined based on the following criteria:

[0074] dist_min i <ediag (7)

[0075] If the above formula is satisfied, then the FDM model element is cut by the boundary line of the influence domain, and the element number is marked. In summary, the dynamic transformation domain mesh is determined by consisting of the far-field FDM model elements contained within the rectangular influence region and the FDM model elements cut by the boundary line of the influence domain (see [link to dynamic transformation domain mesh] for details). Figure 3 ).

[0076] Step 4: Transmit near-field surge information and landslide deposit distribution information to the dynamic conversion domain grid. Interpolate the near-field surge physical quantities carried by SPH water particles to the dynamic conversion domain grid nodes, and interpolate the landslide deposit distribution information carried by SPH soil particles to the dynamic conversion domain grid nodes. This includes the following steps (see the schematic diagram of the interpolation algorithm using velocity vectors as an example). Figure 4 ):

[0077] S4.1: Traverse all SPH particles, determine the dynamic transformation domain grid in which they are located based on their coordinate values, and use cell_of_particle(:) and particle_in_cell(:) to store the dynamic transformation domain grid number corresponding to the particle and the number of SPH particles contained in each dynamic transformation domain grid, respectively.

[0078] S4.2: Traverse all dynamic transformation domain grids, interpolating the near-field surge physical quantities carried by SPH water particles and the landslide deposit distribution information carried by SPH soil particles to the dynamic transformation domain grid nodes (interpolation). Calculate the physical quantity values ​​of SPH particles interpolated to the grid nodes within the grid, using the following formula:

[0079]

[0080] Where, φ i It is the physical quantity value φ at node i of the dynamic transformation domain mesh. j It is the near-field swell physical quantity carried by SPH water particles j, d ij Let be the distance between node i and particle j, and m be a calculation parameter that can be set to 1.

[0081] Step 5: Update the topographic elevation information of the landslide surge far-field propagation FDM model using the accumulation distribution information carried by the grid nodes in the dynamic transformation domain. Specifically, the accumulation depth value `dep` carried by grid node i in the dynamic transformation domain is... i Adding the z-direction value of the terrain coordinates of the original surge far-field propagation FDM model to obtain the updated FDM model terrain elevation information topo(z) is obtained. i The calculation formula is as follows:

[0082] topo(z) i =topo(z) i +dep i (9)

[0083] Where i represents the i-th FDM model mesh node.

[0084] Step 6: Use the near-field surge physical quantities carried by the nodes of the dynamic transformation domain grid as the initial conditions for calculating the far-field propagation FDM model of the landslide surge, and perform far-field calculations of the landslide surge. Since the dynamic transformation domain grid is built on the far-field propagation FDM model, the interpolation process can be directly completed based on the node information index. The transmitted near-field surge physical quantities include: velocity lists u(:), v(:), water depth list h(:), and topographic information using the topographic height topol(:,:,:) formed after landslide triggering, considering the depth of the deposited mass. i .

[0085] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of the equivalent elements of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0086] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain, characterized in that, Includes the following steps: Step 1: Calculate the SPH (Surface Heating Principle) of landslide particles in the near field of the landslide surge to determine whether the landslide has stopped; Step 2: If the landslide stops, then trace all SPH water particles and mark the water particles with non-zero velocities. The area covered is the near-field surge wave propagation range. Step 3: Generate a dynamic transformation domain mesh based on the near-field surge propagation range, far-field calculation model mesh spacing, and node positions; Step 4: Interpolate the near-field surge physical quantities carried by SPH water particles and pass them to the dynamic transformation domain grid nodes; interpolate the landslide accumulation distribution information carried by SPH soil particles and pass it to the dynamic transformation domain grid nodes. Step 5: Update the landslide surge far-field propagation FDM model topographic elevation information using the accumulation distribution information carried by the grid nodes in the dynamic transformation domain; Step 6: Use the near-field surge physical quantities carried by the grid nodes of the dynamic transformation domain as the initial conditions for the calculation of the far-field propagation FDM model of landslide surge, and perform far-field calculation of landslide surge. Step 3 specifically includes the following steps: Step 31: Based on the maximum (xwmax, ywmax) and minimum (xwmin, ywmin) x and y coordinate values ​​of the water particles with non-zero flow velocity, determine the coordinate values ​​of four vertices TZ1(x,y), TZ2(x,y), TZ3(x,y), and TZ4(x,y), where TZ1 corresponds to the point (xwmin, ywmin) and TZ4 corresponds to the point (xwmax, ywmax). Step 32: Based on the coordinates of the four vertices of the rectangular influence region, determine the far-field FDM model elements contained within the rectangular influence region; for any FDM model element, its four nodes are EP1, EP2, EP3, and EP4, if and only if and (3) When established, the FDM model element is located within the rectangular influence area, and the element number is marked. Step 33: Further consider the FDM model elements cut by the boundary line of the affected domain, and first calculate the coordinates of the center point of each element. For any unit ,have: （4） Using the edge vectors of the rectangular influence region, calculate the distance from any cell to the edge vector. First, calculate the four edge vectors of the rectangular influence region: （5） Calculate the minimum distance from the center point of each element to the boundary of the rectangular influence area. : （6） Based on the minimum distance between the grid spacing size (ediag) and the boundary of the rectangular influence area of ​​each cell center point in the far-field calculation model. The FDM model elements that are cut by the boundary line of the affected domain are determined based on the following criteria: （7） If the above formula is satisfied, then the FDM model element is cut by the boundary line of the influence domain and the element number is marked.

2. The method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain as described in claim 1, characterized in that, Step 1 specifically includes: calculating the absolute velocity of all SPH landslide particles by traversing all of them, and calculating the absolute velocity of the i-th SPH particle. The expression is as follows: （1） in, , These are the velocity values ​​of the SPH particles in the i-th landslide body in the x and y directions, respectively; assuming the maximum value... The initial value is -1, and the SPH particles for each landslide are compared. and like Then Amplitude given After completing the traversal, first determine if... The program then reports an error, indicating that the calculation of the particle's absolute velocity maximum value is incorrect; further investigation is needed. and If the landslide particles are in a stopped state, then it is considered that the landslide particles are in a stopped state at this time; otherwise, the landslide has not stopped, and the next time step is entered to update the particle information and continue to determine whether the landslide has stopped.

3. The method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain as described in claim 1, characterized in that, Step 2 specifically includes: calculating the absolute velocity of all SPH water particles, and calculating the absolute velocity of the i-th SPH water particle. The expression is as follows: （2） in, , Let be the velocity values ​​of the i-th SPH particle in the water body in the x and y directions, respectively; if Then, the i-th water body SPH particle is marked as a water body particle with a flow velocity of non-zero; the propagation range of the near-field surge is determined based on the maximum (xwmax, ywmax) and minimum (xwmin, ywmin) x and y coordinate values ​​of the water body particles with a flow velocity of non-zero.

4. The method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain as described in claim 1, characterized in that, Step 4 involves interpolating the near-field surge physical quantities carried by SPH water particles and transmitting them to the dynamic transformation domain grid nodes, and interpolating the landslide deposit distribution information carried by SPH soil particles and transmitting it to the dynamic transformation domain grid nodes; this includes the following steps: Step 41: Traverse all SPH particles and determine the dynamic conversion domain grid in which they are located based on their coordinate values. Use cell_of_particle(:) and particle_in_cell(:) to store the dynamic conversion domain grid number corresponding to the particle and the number of SPH particles contained in each dynamic conversion domain grid, respectively. Step 42: Traverse all dynamic transformation domain grids, interpolating the near-field surge physical quantities carried by SPH water particles and the landslide deposit distribution information carried by SPH soil particles to the dynamic transformation domain grid nodes; calculate the physical quantity values ​​interpolated from SPH particles to the grid nodes within the grid, using the following formula: （8） in, It is the physical quantity value on the grid node i of the dynamic transformation domain. It is the near-field swell physical quantity carried by SPH water particles j. Let be the distance between node i and particle j, and m be the calculation parameter set to 1.

5. The method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain as described in claim 1, characterized in that, Step 5 updates the topographic elevation information of the landslide surge far-field propagation FDM model using the accumulation distribution information carried by the grid nodes in the dynamic transformation domain; wherein, the accumulation depth value carried by the grid node i in the dynamic transformation domain is... The updated FDM model terrain elevation information is obtained by adding the z-direction values ​​of the original surge far-field propagation FDM model terrain coordinates. The calculation formula is as follows: （9） Where i represents the i-th FDM model mesh node.

6. The method for transferring the physical field of a multi-scale model of landslide surge based on a dynamic transformation domain as described in claim 1, characterized in that, Step 6 uses the near-field surge physical quantities carried by the nodes of the dynamic conversion domain grid as the initial conditions for the calculation of the far-field propagation FDM model of landslide surge, and performs far-field calculation of landslide surge; since the dynamic conversion domain grid is established on the basis of the far-field propagation FDM model, the interpolation process is directly completed according to the node information index. The near-field surge physical quantities transmitted include: a list of flow velocities, a list of water depths, and topographic information, which uses the topographic height formed after a landslide triggering the landslide, taking into account the depth of the deposited mass.

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