MPS numerical simulation method and apparatus for the interaction between riverbed sediment and water

Abstract

This invention discloses an MPS numerical simulation method and apparatus for the interaction between riverbed sediment and water. The method includes: establishing an MPS numerical model of the interaction between riverbed sediment and water; setting boundary conditions, flow velocity parameters, and selecting sediment material; setting parameters for the rheological equations based on the selected sediment material; inputting the boundary conditions, flow velocity parameters, and sediment material into the MPS numerical model for solution, obtaining riverbed sediment deformation, and peak and trough values ​​at the sediment-water interface; comparing these values ​​with measured and calculated values; if the verification conditions are met, the simulation is executed; otherwise, the above steps are repeated; based on the verified riverbed sediment deformation and peak and trough values ​​at the sediment-water interface, the influence of flow velocity parameters and sediment material elements on the morphological changes of the riverbed sediment is analyzed.

Description

Technical Field

[0001] This application relates to the field of water conservancy engineering resources and environmental technology, and in particular to an MPS numerical simulation method and apparatus for the interaction between riverbed sediment and water. Background Technology

[0002] Sediment pollution is one of the main sources of endogenous pollution in urban rivers and a prominent research challenge worldwide. Urban rivers are mostly located in plain river networks, characterized by poor flow and slow velocity, making them highly susceptible to severe siltation. The resulting endogenous sediment pollution has a significant impact on the river's aquatic ecosystem and environment. Current research on sediment pollution, both domestically and internationally, is largely limited to on-site observations and still-water model experiments. However, research using mathematical models to study the morphological changes and efficient capture of sediment-overlying water interface remains a global research hotspot.

[0003] Traditional sediment-water numerical models are mostly based on the grid method. While the grid method has a long history, mature development, and wide application, its limitations stem from its Euler-based approach to numerical simulation. When dealing with free water surfaces or multiphase flow interfaces, it requires simulation techniques such as VOF (Volume of Fluid). Furthermore, in simulating sediment-water interactions, the grid method has shortcomings in handling convection and source terms in the governing equations; improper handling can affect computational stability and convergence. Moreover, considering computational efficiency and accuracy, grid method calculations often use simple source terms or analytical solutions, making it difficult to visually represent sediment-water interactions and interface morphological changes. Summary of the Invention

[0004] The purpose of this application is to provide an MPS numerical simulation method and apparatus for the interaction between riverbed sediment and water, so as to solve the technical problems of the interaction between riverbed sediment and overlying water, deformation (peaks and troughs) of water-sand interface and its capture in related technologies.

[0005] According to a first aspect of the embodiments of this application, an MPS numerical simulation method for the interaction between riverbed sediment and water is provided, comprising:

[0006] S11: Establish an MPS numerical model of the interaction between riverbed sediment and water body. The basic equations of the MPS numerical simulation model include: water flow equation, rheological equation, and multiphase flow MPS equation.

[0007] S12: Set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material;

[0008] S13: Input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solution to obtain the riverbed sediment deformation and the peak and trough values ​​of the sediment-water interface.

[0009] S14: The measured sediment deformation and the peak and trough values ​​of the sediment-water interface are compared and verified with the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model. If the verification conditions are met, proceed to S15; otherwise, proceed to S12-S14.

[0010] S15: Based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface that meet the verification conditions, analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment.

[0011] Furthermore, the specific equations of motion, rheological equations, and multiphase flow MPS equations are as follows:

[0012] ① Equation of water flow motion:

[0013]

[0014]

[0015] In the formula: ρ is the fluid density, t is time, u is the velocity vector, d is the calculation dimension, n0 is the initial spatial particle density, p is the pressure, r is the distance between two adjacent spatial particles, W is the core equation, and R... e Let be the search radius of the spatial particle, μ be the dynamic viscosity coefficient of the fluid, v be the volume function, V be the volume integral, and f be the volume force. The subscripts i and j in the above formula represent different particles within the calculation space.

[0016] ② Rheological equations:

[0017]

[0018] Π=(2E m E m ) 0.5

[0019] In the formula, μ0 is the initial dynamic viscosity coefficient, k is the consistency coefficient, π is the strain tensor, n is the flow exponent, τ0 is the yield stress, and E m For strain rate tensor;

[0020] ③ Multiphase flow MPS equations:

[0021]

[0022]

[0023]

[0024]

[0025]

[0026] In the formula, C1 is the spatial fraction of the first phase particle at the multiphase flow interface, C2 is the spatial fraction of the second phase particle at the multiphase flow interface, r is the position vector of the spatial particle, and R e Let R be the search radius of the spatial particle, η be the physical variable of the fluid, and the subscripts PF1 and PF2 represent the search radius R. e The number of spatial particles in different phase fluids within the search radius Re is represented by the subscript PFA, which indicates the total number of spatial particles in all phase fluids within the search radius Re.

[0027] Furthermore, the boundary conditions are calculated as follows:

[0028] ① Setting the boundary of the free surface of the water body

[0029] <n*> i ≤n0β

[0030] In the formula, <n * > represents the spatial particle density. <n0>Where β is the initial spatial particle density, and β is the recognition constant;

[0031] ② Defining the boundary between sediment and water interaction:

[0032]

[0033]

[0034] Furthermore, the high-order precision gradient operator and Laplace operator used in the rheological equations are as follows:

[0035] ①High-order precision gradient operator:

[0036]

[0037]

[0038] In the formula, Φ is a universal variable, r is the position vector of the spatial particle, and R e The search radius for spatial particles;

[0039] ②High-order precision Laplace operator:

[0040]

[0041] Furthermore, the density smoothing transition operator used in the multiphase flow MPS equations is as follows:

[0042] ρ i = <c1> i r f1 + <c2> i ρ f2 .

[0043] Furthermore, the viscosity smoothing transition operator used in the multiphase flow MPS equations is as follows:

[0044] μ i = <c1> i m f1 + <c2> i μ f2 .

[0045] Furthermore, the boundary conditions, flow velocity parameters, and sediment material are input into the MPS numerical model for solution. The basic unit of calculation is a spatial particle, and the scale of the spatial particle is determined according to the calculation area.

[0046] According to a second aspect of the embodiments of this application, an MPS numerical simulation device for the interaction between riverbed sediment and water is provided, comprising:

[0047] A module is established to build a numerical model of the interaction between riverbed sediment and water. The basic equations of the MPS numerical simulation model include: the water flow equation, the rheological equation, and the multiphase flow MPS equation.

[0048] The setting module is used to set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material;

[0049] The solution module is used to input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solution, and to obtain the deformation of the riverbed sediment and the peak and trough values ​​of the sediment-water interface.

[0050] The verification module is used to compare and verify the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model with the measured sediment deformation and the peak and trough values ​​of the sediment-water interface. If the verification conditions are met, the analysis module is executed; otherwise, the creation module is executed and the verification module is executed.

[0051] The analysis module is used to analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface, which meet the verification conditions.

[0052] According to a third aspect of the embodiments of this application, an electronic device is provided, characterized in that it includes:

[0053] One or more processors;

[0054] Memory, used to store one or more programs;

[0055] When the one or more programs are executed by the one or more processors, the one or more processors perform the method as described in the first aspect.

[0056] According to a fourth aspect of the embodiments of this application, a computer-readable storage medium is provided that stores computer instructions thereon, which, when executed by a processor, implement the steps of the method as described in the first aspect.

[0057] The technical solutions provided by the embodiments of this application may include the following beneficial effects:

[0058] As can be seen from the above embodiments, this application adopts an MPS numerical model based on the Lagrange perspective, overcoming technical problems such as the non-convergence of convection and source terms, the difficulty in simulating sediment morphology changes in riverbeds, and the difficulty in capturing the deformation (crests and troughs) at the sediment-water interface in water-sediment multiphase flow simulation. It rationally considers sediment materials such as sand and silt, as well as the interaction mechanism between sediment and water under various flow velocities, and employs a numerical simulation technique for efficient interface capture. This achieves simplified calculation of convection and source terms, convenient simulation of sediment-overlying water two-phase flow motion, and efficient capture of the water-sediment interface (crests and troughs). This invention analyzes sediment morphology changes and sediment-overlying water interface interactions under different parameter combinations, and provides the peak and trough values ​​of sediment deformation caused by sediment-overlying water interaction under various working conditions. This invention provides a feasible predictive analysis technique and method for effectively solving sediment morphology changes caused by dredging, navigation, and flood discharge in natural rivers.

[0059] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0060] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0061] Figure 1 This is a flowchart illustrating an MPS numerical simulation method for the interaction between riverbed sediment and water, according to an exemplary embodiment.

[0062] Figure 2 This is a schematic diagram of the original model layout of a river channel according to an exemplary embodiment.

[0063] Figure 3 This is a schematic diagram of the arrangement of MPS models of different types of bottom sediment materials in a river channel, according to an exemplary embodiment.

[0064] Figure 4 This is a schematic diagram illustrating the interaction, deformation (crests, troughs) and capture of the interface between riverbed sediment and overlying water, according to an exemplary embodiment.

[0065] Figure 5 This is a block diagram of an MPS numerical simulation apparatus for the interaction between riverbed sediment and water, according to an exemplary embodiment. Detailed Implementation

[0066] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0067] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms "a," "the," and "the" as used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0068] Figure 1 This is a flowchart illustrating an MPS numerical simulation method for the interaction between riverbed sediment and water, according to an exemplary embodiment, as shown below. Figure 1 As shown, the method may include the following steps:

[0069] S11: Establish an MPS numerical model of the interaction between riverbed sediment and water body. The basic equations of the MPS numerical simulation model include: water flow equation, rheological equation, and multiphase flow MPS equation.

[0070] S12: Set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material;

[0071] S13: Input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solution to obtain the riverbed sediment deformation and the peak and trough values ​​of the sediment-water interface.

[0072] S14: The measured sediment deformation and the peak and trough values ​​of the sediment-water interface are compared and verified with the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model. If the verification conditions are met, proceed to S15; otherwise, proceed to S12-S14.

[0073] S15: Based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface that meet the verification conditions, analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment.

[0074] As can be seen from the above embodiments, this application adopts an MPS numerical model based on the Lagrange perspective, overcoming technical problems such as the non-convergence of convection and source terms, the difficulty in simulating sediment morphology changes in riverbeds, and the difficulty in capturing the deformation (crests and troughs) at the sediment-water interface in water-sediment multiphase flow simulation. It rationally considers sediment materials such as sand and silt, as well as the interaction mechanism between sediment and water under various flow velocities, and employs a numerical simulation technique for efficient interface capture. This achieves simplified calculation of convection and source terms, convenient simulation of sediment-overlying water two-phase flow motion, and efficient capture of the water-sediment interface (crests and troughs). This invention analyzes sediment morphology changes and sediment-overlying water interface interactions under different parameter combinations, and provides the peak and trough values ​​of sediment deformation caused by sediment-overlying water interaction under various working conditions. This invention provides a feasible predictive analysis technique and method for effectively solving sediment morphology changes caused by dredging, navigation, and flood discharge in natural rivers.

[0075] This application leverages the advantages of the MPS method in handling convection and source terms in multiphase flow calculations, achieving efficient processing and calculation of convection and source terms in the simulation of riverbed sediment-water interaction. Simultaneously, it presents the state changes of riverbed sediment-water interaction under different hydrodynamic conditions, successfully reversing the interaction patterns of riverbed sediment-water in various flow regimes. Furthermore, utilizing the inherent advantage of the MPS method in efficiently capturing multiphase flow interfaces, it achieves accurate capture of the riverbed sediment-water interface.

[0076] In the specific implementation of S11: an MPS numerical model of the interaction between riverbed sediment and water body is established. The basic equations of the MPS numerical simulation model include: water flow motion equation, rheological equation, and multiphase flow MPS equation.

[0077] Specifically, in the embodiments, the flow state of hydraulic phase particles is simulated using the water flow equation (i.e., the Navier-Stokes equation), the viscosity changes and flow state of sediment phase particles are simulated using the rheological equation (i.e., the Herschel-Buckley equation), and the multiphase flow MPS equation is used to simulate and characterize the interaction between riverbed sediment and water, the changes in interface morphology, and the changes in the physical characteristics of particles near the interface. After implementing the above steps, the MPS method involved in this invention can utilize multiphase flow particles to characterize the movement laws of riverbed sediment and water phases, thereby efficiently and accurately simulating the interaction between riverbed sediment and water.

[0078] The fundamental equations of the MPS numerical simulation model include: the water flow equation, the rheological equation, and the multiphase flow MPS equation, as detailed below:

[0079] ① Equation of water flow motion:

[0080]

[0081]

[0082] In the formula: ρ is the fluid density, t is time, u is the velocity vector, d is the calculation dimension, n0 is the initial spatial particle density, p is the pressure, r is the distance between two adjacent spatial particles, W is the core equation, and R... e Let be the search radius of the spatial particle, μ be the dynamic viscosity coefficient of the fluid, v be the volume function, V be the volume integral, and f be the volume force. The subscripts i and j in the above formula represent different particles within the calculation space.

[0083] ② Rheological equations:

[0084]

[0085] Π=(2E m E m ) 0.5

[0086] In the formula, μ0 is the initial dynamic viscosity coefficient, k is the consistency coefficient, π is the strain tensor, n is the flow exponent, τ0 is the yield stress, and E m For strain rate tensor;

[0087] ③ Multiphase flow MPS equations:

[0088]

[0089]

[0090]

[0091]

[0092]

[0093] In the formula, C1 is the spatial fraction of the first phase particle at the multiphase flow interface, C2 is the spatial fraction of the second phase particle at the multiphase flow interface, r is the position vector of the spatial particle, and R e Let R be the search radius of the spatial particle, η be the physical variable of the fluid, and the subscripts PF1 and PF2 represent the search radius R. e The number of spatial particles in different phase fluids within the search radius Re is represented by the subscript PFA, which indicates the total number of spatial particles in all phase fluids within the search radius Re.

[0094] The density smoothing transition at the interface of the multiphase flow MPS equation is calculated using the above equation, and the calculation equation is shown below:

[0095] ρ i = <c1> i r f1 + <c2> i ρ f2

[0096] The above equation is used to calculate the viscosity smoothing transition at the interface of the multiphase flow MPS equation. The calculation equation is shown below:

[0097] μi i = <c1> i m f1 + <c2> i μ f2

[0098] In the specific implementation of S12: set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material;

[0099] Specifically, in this embodiment, the inflow boundary condition is set as a flow rate (velocity) boundary, the outflow boundary condition is set as a water level boundary, the velocity parameters are set to three types: low velocity (0.01 m / s), medium velocity (0.05 m / s), and high velocity (0.09 m / s), and the sediment material is set to sandy (density 1.06 × 10⁻⁶ m / s). 3 kg / m 3 ) and silt (density 2.72×10 3 kg / m 3 Two types of methods are used, and the parameters of the rheological equations are set according to the different sediment materials. Therefore, embodiments of the present invention can simulate the interaction between river sediment and water under different flow conditions and different sediment materials, and obtain the morphological changes of the river sediment-water interface under different conditions.

[0100] The boundary conditions are calculated as follows:

[0101] ① Setting the boundary of the free surface of the water body

[0102] <n*> i ≤n0β

[0103] In the formula, <n * > represents the spatial particle density. <n0>Where β is the initial spatial particle density, and β is the recognition constant;

[0104] ② Defining the boundary between sediment and water interaction:

[0105]

[0106]

[0107] The high-order precision gradient operator and Laplace operator used in the rheological equations are as follows:

[0108] ①High-order precision gradient operator:

[0109]

[0110]

[0111] In the formula, Φ is a universal variable, r is the position vector of the spatial particle, and R e The search radius for spatial particles;

[0112] ②High-order precision Laplace operator:

[0113]

[0114] ③ The density smoothing transition operator used in the multiphase flow MPS equation is as follows:

[0115] ρ i = <c1> i r f1 + <c2> i ρ f2 .

[0116] ④ The viscosity smoothing transition operator used in the multiphase flow MPS equations is as follows:

[0117] μ i = <c1> i m f1 + <c2> i μ f2 .

[0118] In the specific implementation of S13: the boundary conditions, flow velocity parameters and sediment material are input into the MPS numerical model for solution to obtain the riverbed sediment deformation and the peak and trough values ​​of the sediment-water interface.

[0119] Specifically, boundary conditions, flow velocity parameters, and sediment material are set in the MPS numerical model and numerical simulations are performed to obtain the deformation curve of the riverbed sediment and the peak and trough values ​​of the sediment-water interface. The deformation curves of the riverbed sediment and the specific values ​​of the peaks and troughs of the sediment-water interface are compared, and then the above data are used to conduct a comparative analysis of the interaction between the riverbed sediment and the water body under different conditions.

[0120] The boundary conditions, flow velocity parameters, and sediment material are input into the MPS numerical model for solution. The basic unit of calculation is a spatial particle, and the size of the spatial particle depends on the calculation area.

[0121] In the specific implementation of S14: The measured sediment deformation, peak and trough values ​​of the sediment-water interface are compared and verified with the sediment deformation, peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model. If the verification conditions are met, proceed to S15; otherwise, proceed to S12-S14.

[0122] Specifically, in the embodiments, the comparison and verification condition between MPS numerical simulation and physical experimental data is based on an absolute error of less than 5%. When the error between the MPS calculated data of the peaks and troughs of the sediment-water interface and the physical experimental data meets the verification condition, it is considered that the MPS numerical model can accurately simulate the interaction between river sediment and water and can accurately obtain the deformation curve of river sediment.

[0123] In the specific implementation of S15: Based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface that meet the verification conditions, the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment is analyzed.

[0124] Specifically, six working conditions were calculated in the embodiments, each consisting of different combinations of water flow velocity and sediment material. Clearly, flow velocity parameters and sediment material factors have a certain impact on the morphological changes of riverbed sediment. The above working conditions were set using single-factor discrimination, combining factors to form different calculation working conditions, and thereby calculating the peak and trough values ​​of the riverbed sediment-water interface under different working conditions. Using the peak and trough values ​​obtained from MPS calculations, the influence of flow velocity parameters and sediment material factors on the morphological changes of riverbed sediment was quantitatively analyzed, thereby enabling the interpretation and subsequent application of MPS numerical simulation results.

[0125] This invention provides a feasible predictive analysis technique and method for effectively addressing changes in the morphology of bottom sediment caused by dredging, navigation, and flood discharge in natural river channels.

[0126] Example:

[0127] This embodiment uses the MPS method, combining the basic equations of step S1, the calculation equations of S2, and the boundary conditions. Sandy and silty sediments are selected as the sediment materials, and three flow velocity parameters (high, medium, and low) are chosen. The particle method based on the Lagrange perspective is used to solve the established kinematic equations of the riverbed sediment and water body. The basic computational unit is the spatial particle, and the spatial particle scale is D. L =0.01m.

[0128] ① Layout of the river model: The river model is 40m long with a bottom slope of 1:100,000. The stable flow section is 4m from the inlet to 2m from the outlet. The water enters from the left side of the model, and the water density is 1.0 × 10⁻⁶. 3 kg / m 3 The kinematic viscosity coefficient is 1.01 × 10⁻⁶. -6 m 2 / s, such as Figure 2 and Figure 3 As shown.

[0129] ② Selection and Layout of Riverbed Sediment: Two types of sediment materials were selected: sandy and silty. The different materials were distinguished by their physical parameters such as density and kinematic viscosity. The riverbed sediment materials were evenly spread on the bottom of the model.

[0130] ③The initial working conditions are: water depth 0.15m, bottom mud layer thickness 0.05m.

[0131] ④ The selection parameters for bottom sediment material are: sand density 1.06×10 3 kg / m 3 The density of the silt is 2.72 × 10⁻⁶. 3 kg / m 3 .

[0132] ⑤ The flow velocity selection parameters are: low velocity 0.01m / s, medium velocity 0.05m / s, and high velocity 0.09m / s.

[0133] ⑥ All structures in the model use impermeable solid boundaries.

[0134] In this example, the sediment deforms under the influence of shear stress from the overlying water flow. This invention calculates and analyzes the deformation characteristics of different sediment materials under different water flow velocities, including the peak and trough values ​​of the sediment deformation. A peak refers to the highest vertical distance between the wavy deformation at the interface and the riverbed, while a trough refers to the lowest vertical distance between the wavy deformation at the interface and the riverbed. Figure 2 , Figure 4 As shown.

[0135] (4) Simulation results and statistical analysis

[0136] Simulation results show that when the shear stress at the sediment-overlying water interface increases to the sediment initiation critical value, the river sediment undergoes shear deformation, its shape changes, and it produces horizontal displacement and vertical deformation. Its motion is closely related to the physical properties of the sediment itself, the flow velocity of the overlying water, and the deformation process of the sediment-water interface.

[0137] Table 1. Index parameters under different working condition combinations

[0138]

[0139] Table 1 presents the index parameters under different working condition combinations. Several conclusions can be drawn from comparing these parameters:

[0140] 1. Whether or not sediment is activated is mainly controlled by its own physical properties and the influence of the overlying water body on its shear stress. The greater the flow velocity of the overlying water body, the greater the shear stress at the sediment-overlying water interface. When the shear stress reaches a critical value, the river sediment begins to deform and move. Obviously, under condition 2-1, the river water flow did not meet the activation conditions for silty sediment. Under other conditions, the river water flow met the necessary conditions for sediment activation.

[0141] 2. The morphological changes and movement patterns of bottom sediment are less affected by the river depth and the thickness of the bottom sediment layer. This is because the interaction between the bottom sediment and the overlying water body occurs at the interface between the two, and the water depth and the thickness of the bottom sediment layer do not affect the movement patterns of the two at the interface.

[0142] 3. The greater the flow velocity of the overlying water, the greater the shear stress on the sediment layer, and consequently, the more severe the deformation of the sediment. This is reflected in the parameters in Table 1, namely, the larger the deformation peaks and troughs. For sandy sediments with low critical shear stress, the shear stress generated by a relatively low water flow velocity is sufficient to induce deformation. For silty sediments with high critical stress, the shear stress generated by a relatively low water flow velocity is insufficient to induce deformation; the overlying water must reach a certain flow velocity to cause deformation and subsequent movement of the silty sediment. The morphological changes at the interface between riverbed sediment and overlying water can be observed. Figure 4 .

[0143] In summary, the deformation and movement patterns of riverbed sediments under the influence of water flow are closely related to the physical properties of the sediments themselves and the flow characteristics of the overlying water.

[0144] Due to the two-dimensional modeling characteristics of MPS numerical simulation, for the simulation of riverbed sediment-overlying water, only when the water flow velocity is stable enough and the sediment viscosity coefficient is large enough can the sediment particles maintain their overall deformation. Otherwise, a small number of sediment particles will enter the water body and form suspended sediment.

[0145] Corresponding to the aforementioned embodiments of the MPS numerical simulation method for the interaction between riverbed sediment and water, this application also provides embodiments of an MPS numerical simulation apparatus for the interaction between riverbed sediment and water.

[0146] Figure 5 This is a block diagram of an MPS numerical simulation apparatus for the interaction between riverbed sediment and water, according to an exemplary embodiment. (Refer to...) Figure 5 The device includes:

[0147] Module 21 is established to establish an MPS numerical model of the interaction between riverbed sediment and water. The basic equations of the MPS numerical simulation model include: water flow equation, rheological equation, and multiphase flow MPS equation.

[0148] The setting module 22 is used to set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material;

[0149] The solver module 23 is used to input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solving, and to obtain the deformation of the riverbed sediment and the peak and trough values ​​of the sediment-water interface.

[0150] The verification module 24 is used to compare and verify the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model with the measured sediment deformation and the peak and trough values ​​of the sediment-water interface. If the verification conditions are met, the analysis module is executed; otherwise, the creation module is executed and the verification module is executed.

[0151] Analysis module 25 is used to analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface that meet the verification conditions.

[0152] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0153] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0154] Accordingly, this application also provides an electronic device, comprising: one or more processors; a memory for storing one or more programs; and when the one or more programs are executed by the one or more processors, causing the one or more processors to implement the MPS numerical simulation method for the interaction between riverbed sediment and water as described above.

[0155] Accordingly, this application also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, implement the MPS numerical simulation method for the interaction between riverbed sediment and water as described above.

[0156] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

[0157] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A numerical simulation method for the interaction between riverbed sediment and water, characterized in that, include: S11: Establish an MPS numerical model of the interaction between riverbed sediment and water body. The basic equations of the MPS numerical model include: water flow equation, rheological equation, and multiphase flow MPS equation. S12: Set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material; S13: Input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solution to obtain the riverbed sediment deformation and the peak and trough values ​​of the sediment-water interface. S14: The measured sediment deformation and the peak and trough values ​​of the sediment-water interface are compared and verified with the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model. If the verification conditions are met, proceed to S15; otherwise, proceed to S12-S14. S15: Based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface that meet the verification conditions, analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment. The specific equations of water flow motion, rheological equations, and multiphase flow MPS equations are as follows: ① Equation of water flow motion: ； ； In the formula: ρ Let be the fluid density, and t be the time. u It is a velocity vector. d To calculate the dimension, n 0 represents the initial space particle density for calculation. p For pressure, r This represents the distance between two adjacent spatial particles. W As the core equation, R e The search radius for spatial particles. μ Let be the dynamic viscosity coefficient of the fluid. v It is a volume function. V For volume integral, f For volume forces, the subscripts in the above formula... i , j These represent different particles within the computational space; ② Rheological equations: ； ； In the formula, μ 0 represents the initial dynamic viscosity coefficient. k Π is the consistency coefficient, and Π is the strain tensor. n For traffic index, τ 0 represents the yield stress. E m For strain rate tensor; ③ Multiphase flow MPS equations: ； ； ； ； ； In the formula, C 1 represents the spatial fraction of the first phase particle at the multiphase flow interface. C 2 represents the spatial fraction of the second phase particles at the multiphase flow interface. r Let be the position vector of the spatial particle. R e The search radius for spatial particles. η For the physical variables of the fluid, the subscripts PF1 and PF2 represent the search radius. R e The number of spatial particles in different phase fluids within the range, with the subscript PFA representing the search radius. R e The total number of spatial particles in all phase fluids within the range.

2. The MPS numerical simulation method for the interaction between riverbed sediment and water body according to claim 1, characterized in that, The boundary conditions are calculated as follows: ① Setting the boundary of the free surface of the water body ； In the formula, < n * > represents the spatial particle density. n 0 represents the initial spatial particle density. β To identify constants; ② Defining the boundary between sediment and water interaction: ； 。 3. The MPS numerical simulation method for the interaction between riverbed sediment and water body according to claim 1, characterized in that, The high-order precision gradient operator and Laplace operator used in the rheological equations are as follows: ①High-order precision gradient operator: ； ； In the formula, Φ For general variables, r Let be the position vector of the spatial particle. R e The search radius for spatial particles; ②High-order precision Laplace operator: 。 4. The MPS numerical simulation method for the interaction between riverbed sediment and water body according to claim 1, characterized in that, The density smoothing transition operator used in the multiphase flow MPS equations is as follows: 。 5. The MPS numerical simulation method for the interaction between riverbed sediment and water body according to claim 1, characterized in that, The viscosity smoothing transition operator used in the multiphase flow MPS equations is as follows: 。 6. The MPS numerical simulation method for the interaction between riverbed sediment and water body according to claim 1, characterized in that, The boundary conditions, flow velocity parameters, and sediment material are input into the MPS numerical model for solution. The basic unit of calculation is a spatial particle, and the size of the spatial particle depends on the calculation area.

7. An MPS numerical simulation device for the interaction between riverbed sediment and water, characterized in that, The apparatus for performing the method of claim 1 includes: A module is established to build a multiphase flow MPS numerical model of the interaction between riverbed sediment and water. The basic equations of the MPS numerical model include: the flow motion equation, the rheological equation, and the multiphase flow MPS equation. The setting module is used to set boundary conditions, set flow velocity parameters, select sediment material, and set the parameters of the rheological equation according to the selected sediment material; The solution module is used to input the boundary conditions, flow velocity parameters and sediment material into the MPS numerical model for solution, and to obtain the deformation of the riverbed sediment and the peak and trough values ​​of the sediment-water interface. The verification module is used to compare and verify the sediment deformation and the peak and trough values ​​of the sediment-water interface calculated by the MPS numerical model with the measured sediment deformation and the peak and trough values ​​of the sediment-water interface. If the verification conditions are met, the analysis module is executed; otherwise, the setting module is executed and the verification module is executed. The analysis module is used to analyze the influence of flow velocity parameters and sediment material elements on the morphological changes of riverbed sediment based on the deformation of riverbed sediment and the peak and trough values ​​of the sediment-water interface, which meet the verification conditions.

8. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-6.

9. A computer-readable storage medium storing computer instructions thereon, characterized in that, When executed by the processor, this instruction implements the steps of the method as described in any one of claims 1-6.

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