A nonlinear coupled simplified simulation method and system for dynamic water grouting to fill fractures

Abstract

The present invention belongs to the technical field of grouting simulation and specifically discloses a nonlinear coupled simplified dynamic water grouting simulation method and system for filling fractures. The method comprises: constructing a geometric model of the area to be simulated, constructing a fluid continuity equation and a momentum equation based on initialized model parameters, and calculating the grouting pressure and grouting velocity at the current time step; constructing a concentration field equation based on the velocity field at the current time step, and solving the slurry concentration distribution and grouting velocity at the current time step based on the discretized concentration field equation and momentum equation; constructing a phase fraction equation based on the grouting velocity at the current time step to obtain the slurry diffusion morphology in the water-rich filling fracture at the current time step; and repeating the above process for each time step to complete the simulation of dynamic water grouting for filling water-rich fractures. While simplifying the algorithm, the present invention balances computational efficiency and accuracy, achieving an accurate description of the slurry flow characteristics in fractured porous media.

Description

Technical Field

[0001] The present invention relates to the technical field of grouting simulation, and in particular to a nonlinear coupled simplified fissure filling dynamic water grouting simulation method and system. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] With the increasing demand for underground construction, the scale and number of transportation and engineering construction have generally shown an increasing trend. The geological environment faced by underground engineering construction has also become increasingly complex. Adverse geological conditions such as strong karst, deep burial, high ground pressure, and high ground temperature have led to frequent water and mud disasters, which seriously threaten the safety of life and property of construction workers and the progress of the project.

[0004] Groundwater disasters are one of the most important underground engineering disasters. Grouting is one of the most important treatment methods for groundwater disasters in underground engineering. Underground rock fissures are important water conduits for groundwater disasters. However, underground rock fissures are hidden, and the diffusion of grouting slurry in underground rock fissures is non-visible. Therefore, exploring the mechanism of dynamic water grouting to fill fissures is of great significance for improving the stability of underground engineering, preventing and controlling geological disasters, optimizing grouting effects, adapting to complex geological conditions, selecting appropriate grouting materials, and saving engineering costs.

[0005] The means of exploring the sealing mechanism of dynamic water grouting in fractures generally adopt the methods of model testing and numerical calculation. In terms of model testing, the reduced-scale experimental model will produce scale effects, which makes it difficult to fully reflect the slurry diffusion and water flow characteristics in actual working conditions. Secondly, the simplification of experimental conditions, such as the idealization of fracture structure and fluid flow characteristics, cannot fully cover the complex actual geological environment. In addition, model testing is costly and time-consuming, and it is difficult to quickly adjust and verify various working conditions. Moreover, during the dynamic grouting process, experimental means make it difficult to accurately observe microscopic details such as slurry diffusion in fractures. In terms of numerical calculation, the existing simulation methods of dynamic water grouting for filling fractures are mainly limited by the treatment of nonlinear fluid flow under complex dynamic water conditions, especially when the fracture scale and flow rate are large, the traditional Darcy law cannot accurately describe the flow process. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a nonlinear coupled simplified dynamic water grouting simulation method and system for filling fractures. The Darcy-Forchheimer equation is used to describe the slurry flow process in a water-rich fracture filling medium environment. The viscous permeability coefficient and inertial permeability coefficient of the porous medium are introduced, and the permeability properties of each grid in the fracture model are defined, thereby realizing the optimized simulation of the porous environment of the fracture filling medium.

[0007] In some embodiments, the following technical solutions are adopted:

[0008] A simplified nonlinear coupling method for simulating dynamic water grouting to fill fractures includes:

[0009] Construct a geometric model of the area to be simulated, divide the fluid calculation grid into the geometric model, and initialize the model parameters;

[0010] Constructing a fluid continuity equation and a momentum equation based on the initialized model parameters. In the momentum equation, the Darcy-Forchheimer law is used to describe the relationship between pressure gradient and velocity, and the viscous permeability coefficient and the inertial permeability coefficient are introduced.

[0011] Based on the discretized fluid continuity equation and momentum equation, the grouting pressure and grouting velocity of the current time step are calculated; the concentration field equation is constructed according to the velocity field of the current time step, and the slurry concentration distribution and grouting velocity of the current time step are obtained based on the coupled solution of the discretized concentration field equation and momentum equation;

[0012] According to the grouting velocity of the current time step, the phase fraction equation is constructed to obtain the slurry diffusion pattern in the water-rich filling fracture at the current time step;

[0013] By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained;

[0014] The above process is repeated for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich fracture filling.

[0015] As a further solution, the momentum equation is specifically:

[0016]

[0017] Where U represents the multiphase velocity, ρ represents the density, represents the gradient operator, which is used to describe the change of vector field or scalar field in space, μ represents the dynamic viscosity coefficient, μD represents the viscous permeability coefficient, represents the inertial permeability coefficient, f g represents the effect of volume force on the fluid, I represents the unit tensor, and F represents the source term; φ(Re) is the interpolation function, 0≤φ(Re)≤1, and Re is the Reynolds number of the grid area.

[0018] As a further solution, the interpolation function φ(Re) is specifically taken as:

[0019] When Re<<10, φ(Re)=1, which means viscosity dominates.

[0020] When Re>>10, φ(Re)=0, and inertia dominates;

[0021] On this basis, when viscosity dominates and inertia dominates, the specific value of Re is set according to actual needs;

[0022] When Re takes other intermediate values, φ(Re) transitions smoothly between 0 and 1.

[0023] As a further solution, the concentration field equation is constructed based on the velocity field of the current time step, specifically:

[0024]

[0025] Where C represents the concentration of the slurry, D is the concentration diffusion coefficient, S represents the source of the new concentration of the slurry during the grouting process, and R represents the part of the slurry that is consumed or reduced due to certain physical or chemical mechanisms during the flow and diffusion process.

[0026] As a further solution, the phase fraction equation is constructed according to the grouting velocity at the current time step, specifically:

[0027]

[0028] Among them, α s represents the slurry phase fraction, and U represents the multiphase velocity.

[0029] As a further solution, the discrete injection time transmission equation is specifically:

[0030]

[0031] Among them, T is the injection duration at the current moment, U represents the multiphase velocity, α w represents the water phase fraction, α s represents the slurry phase fraction, H represents the proportional coefficient, U r Indicates the relative movement velocity between the slurry phase and the water phase.

[0032] As a further solution, a geometric model of the area to be simulated is constructed, specifically:

[0033] Obtain the lithology, filling fracture geometry, filling medium type and distribution data of the area to be simulated, and construct a three-dimensional geometric model of water-rich filling fractures.

[0034] As a further solution, it also includes: visualizing the simulated three-dimensional flow field, pressure distribution and time series data, and animating the velocity field, concentration field and slurry diffusion morphology during the simulation process.

[0035] In other embodiments, the following technical solutions are adopted:

[0036] A nonlinear coupled simplified dynamic water grouting simulation system for filling fractures, including:

[0037] Parameter initialization module, used to build the geometric model of the area to be simulated, divide the fluid calculation grid for the geometric model, and initialize the model parameters;

[0038] The velocity simulation module is used to construct the fluid continuity equation and momentum equation based on the initialized model parameters. In the momentum equation, the Darcy-Forchheimer law is used to describe the relationship between pressure gradient and velocity, and the viscous permeability coefficient and inertial permeability coefficient are introduced. Based on the discretized fluid continuity equation and momentum equation, the grouting pressure and grouting velocity at the current time step are calculated;

[0039] The concentration simulation module is used to construct the concentration field equation according to the velocity field of the current time step, and obtain the slurry concentration distribution and grouting velocity of the current time step based on the coupling solution of the discretized concentration field equation and momentum equation;

[0040] Phase fraction simulation module, which is used to construct the phase fraction equation according to the grouting velocity at the current time step and obtain the slurry diffusion morphology in the water-rich filling fracture at the current time step;

[0041] By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained;

[0042] The iterative calculation module is used to repeat the above process for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures.

[0043] In other embodiments, the following technical solutions are adopted:

[0044] A terminal device includes a processor and a memory, wherein the processor is used to implement instructions; the memory is used to store multiple instructions, and the instructions are suitable for the processor to load and execute the above-mentioned nonlinear coupling simplified dynamic water grouting simulation method for filling fractures.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] (1) When constructing the momentum equation, this method captures the linear and nonlinear relationships between pressure gradient and velocity during dynamic water grouting based on the Darcy-Forchheimer law, particularly emphasizing the inertial effect under high Reynolds number conditions. By introducing viscous permeability and inertial permeability parameters, this method simplifies the algorithm while balancing computational efficiency and accuracy, achieving an accurate description of the flow characteristics of slurries in fractured porous media.

[0047] (2) The present invention comprehensively considers different flow conditions dominated by viscosity and inertia, defines viscous permeability and inertial permeability coefficients, and constructs an adaptive model by introducing a difference function. It realizes the dynamic switching of the dominant characteristics of the permeability coefficient of the local area Reynolds number and the adaptive adjustment of the fluid flow characteristics in the momentum equation; it solves the computational difficulty of characterizing the local anisotropic permeability characteristics under complex flow conditions in porous media.

[0048] (3) The present invention constructs a concentration field equation by considering the deposition, adsorption or accumulation effects of slurry particles, and accurately describes the concentration changes of slurry caused by dynamic water scouring in water-rich filling fracture media and the deposition of slurry particles in the filling medium. Combined with the momentum equation, the slurry concentration distribution and grouting velocity at the current time step are solved to achieve accurate simulation of grouting diffusion in water-rich filling fractures.

[0049] Other features and advantages of additional aspects of the present invention will be given in part in the following description and in part will become obvious from the following description or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a flow chart of a simplified nonlinear coupling method for simulating dynamic water grouting for filling fractures in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0052] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0053] Example 1

[0054] In one or more embodiments, a nonlinear coupled simplified dynamic water grouting simulation method for filling fractures is disclosed, combining Figure 1 , specifically including:

[0055] S101: Construct a geometric model of the area to be simulated, divide the geometric model into a fluid calculation grid, and initialize model parameters.

[0056] In this embodiment, a three-dimensional geometric model of water-rich filled fractures is constructed by collecting relevant data of the area to be simulated and the surrounding geology, including lithology, geometry of filled fractures, type of filling medium and its distribution;

[0057] The fluid calculation grid is divided on the three-dimensional geometric model of water-filled fractures, and the continuous calculation domain is discretized into each control volume (i.e., grid calculation unit) based on the finite volume method (FVM).

[0058] According to the actual engineering conditions, the parameters of the three-dimensional geometric model of water-rich filling fractures, such as boundary conditions, grouting speed, grouting pressure, slurry diffusion form, dynamic water initial flow field, gravity field, etc. are initialized and set.

[0059] S102: Construct the fluid continuity equation and momentum equation based on the initialized model parameters; in the momentum equation, use the Darcy-Forchheimer law to describe the relationship between pressure gradient and velocity, and introduce the viscous permeability coefficient and inertial permeability coefficient.

[0060] Specifically, the continuity equation describes the conservation of mass for incompressible fluids, ensuring that the volume of the fluid remains constant during flow, with no accumulation or loss of mass. The fluid continuity equation is:

[0061]

[0062] Where U represents the multiphase velocity, Represents the gradient operator, which is used to describe the change of a vector field or scalar field in space.

[0063] The momentum equation describes the effects of fluid inertia, pressure gradient, rheological properties, gravity, and external forces on slurry migration. Combining the momentum equation with the continuity equation and the phase fraction equation can solve the flow behavior of slurry in fractures. The momentum equation is constructed based on the grouting velocity, grouting pressure, phase fraction, and slurry viscosity.

[0064] The momentum equation is specifically:

[0065]

[0066] where U represents the multiphase velocity, p represents the fluid pressure, τ represents the shear stress tensor, ρ represents the density, g represents the gravity vector, and F represents the source term.

[0067] In this example, in order to consider the influence of viscous resistance (Darcy term) and inertial effect (Forchheimer term) on the flow, the Darcy-Forchheimer law is introduced to describe the relationship between pressure gradient and velocity. At the same time, considering the different flow conditions dominated by viscosity and inertia, the viscous permeability and inertial permeability coefficients are introduced, specifically:

[0068]

[0069] Substituting the pressure gradient term, viscous permeability, and inertial permeability coefficients into the momentum equation, we obtain:

[0070]

[0071] Where U represents the multiphase velocity, ρ represents the density, represents the gradient operator, which is used to describe the change of vector field or scalar field in space, μ represents the dynamic viscosity coefficient, μD represents the viscous permeability coefficient, represents the inertial permeability coefficient, f g represents the effect of volume force on the fluid, I represents the unit tensor, F represents the source term; φ(Re) is the interpolation function, 0≤φ(Re)≤1, Re is the Reynolds number of the 0 grid area.

[0072] When Re<<10, φ(Re)=1, which means viscosity dominates.

[0073] When Re>>10, φ(Re)=0, and inertia dominates;

[0074] On this basis, when viscosity dominates and inertia dominates, the specific value of Re is set according to actual needs; for example: when Re≤t1, φ(Re)=1; when Re≥t2, φ(Re)=0; t1 and t2 are both set values.

[0075] When Re takes other intermediate values ​​(i.e., Re takes a value between t1 and t2), a smooth transition function is introduced to describe φ(Re). The smooth transition function can be, but is not limited to, the following:

[0076] (1) Exponential function type

[0077]

[0078] Among them, Re c represents the critical value of control transition, and k represents the steepness of control transition.

[0079] (2) Inverse hyperbolic tangent function type

[0080]

[0081] Among them, Re c represents the critical value of control transition, and k represents the steepness of control transition.

[0082] (3) Power function type

[0083]

[0084] Where n represents the control decay speed.

[0085] This embodiment introduces a difference function to construct an adaptive model, achieving dynamic switching of the dominant characteristic of the local area Reynolds number on the permeability coefficient and adaptive adjustment of the fluid flow characteristics in the momentum equation; it solves the computational difficulty of characterizing local anisotropic permeability characteristics under complex flow conditions in porous media.

[0086] S103: Calculate the grouting pressure and grouting velocity of the current time step based on the discretized fluid continuity equation and momentum equation;

[0087] The continuity equation and momentum equation are discretized, and the discrete continuity equation is:

[0088] ∑ j F ij =0;

[0089] Among them, F ij represents the mass flow rate from control volume i to the adjacent control volume j.

[0090] The discretized momentum equation is:

[0091]

[0092] Among them, ρ i represents the fluid density, U represents the multiphase velocity, represents the velocity of the control volume i at the current time step, represents the velocity of the control volume i at the next time step, U ij represents the fluid velocity between control volume i and control volume j, ∑ j F ij U ij represents the convection term, represents the viscosity diffusion term, S i represents the source term, F ij represents the mass flow rate from control volume i to the adjacent control volume j.

[0093] The discretized momentum equation is combined with the continuity equation to solve the grouting pressure according to the predicted grouting velocity, and the grouting velocity is solved according to the grouting pressure. The grouting pressure and grouting velocity are calculated iteratively until the number of iterations is reached. The grouting pressure and grouting velocity obtained are the grouting pressure and grouting velocity of the current time step.

[0094] S104: Constructing a concentration field equation based on the velocity field of the current time step, and solving the discretized concentration field equation and momentum equation in a coupled manner to obtain the slurry concentration distribution and grouting velocity of the current time step.

[0095] Specifically, the concentration field equation considering the deposition, adsorption or accumulation of slurry particles is constructed based on the velocity field of the current time step, specifically:

[0096]

[0097] in, represents the rate of change of concentration with time, represents the convection term, D is the concentration diffusion coefficient, C represents the concentration of the slurry, D is the concentration diffusion coefficient, S represents the source of new concentration of the slurry during the grouting process, and R represents the part of the slurry that is consumed or reduced due to some physical or chemical mechanisms during the flow and diffusion process.

[0098] The concentration field equation is discretely solved and the discretized equation is:

[0099]

[0100] in, and Indicates the slurry concentration between the current time step and the next time step, V i represents the volume of the control volume, F ij represents the mass flow rate from control volume i to adjacent control volume j, C ij represents the concentration value on the boundary, D ij represents the diffusion coefficient between control volumes i and j, d ij represents the distance between control volumes i and j, A ij represents the boundary area between control volumes i and j, S i represents the concentration generation within the control volume i, R i Denotes the concentration consumption within the control volume i.

[0101] The concentration field equation of this embodiment can accurately describe the concentration changes caused by the scouring of slurry by dynamic water in a water-rich fractured medium and the deposition of slurry particles in the filling medium.

[0102] The discretized concentration field equation is coupled with the momentum equation to obtain the slurry concentration distribution and grouting velocity at the current time step.

[0103] S105: Constructing a phase fraction equation based on the grouting velocity at the current time step to obtain the slurry diffusion morphology in the water-rich filling fracture at the current time step.

[0104] Specifically, the phase fraction equation is:

[0105]

[0106] Among them, α s represents the slurry phase fraction, and U represents the multiphase velocity.

[0107] The phase fraction equation is discretely solved to obtain the slurry diffusion pattern in the water-filled fracture at the current time step. The discrete equation of the phase fraction is:

[0108]

[0109] in, represents the slurry phase fraction of control volume i at the next time step, represents the slurry phase fraction of the control volume i at the current time step, Δt represents the time step, V i represents the volume of control volume i, F ij represents the mass flow rate, α s,ij represents the phase fraction of the slurry phase on the boundary between control volumes i and j.

[0110] S106: By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained, that is, the duration from the start of slurry injection to any time step, which is used to calculate the values ​​of various parameters at a certain moment.

[0111] Based on the basic principles of the finite volume method, a calculation formula for the injection time T of any slurry micro-group from the start of injection into the fracture to the current moment is established. Combined with the specific application principles of the scalar transport equation, the injection time transmission equation is constructed as follows:

[0112]

[0113] Among them, T is the injection duration at the current moment, U represents the multiphase velocity, α w represents the water phase fraction, α s represents the slurry phase fraction, H represents the proportional coefficient, U r Indicates the relative movement velocity between the slurry phase and the water phase.

[0114] According to the grouting speed of the current time step, a discrete injection time transmission equation is constructed to obtain the slurry injection duration of the current time step;

[0115] S107: Repeat the above process for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures.

[0116] Through the iterative calculation of steps S102-S106, the grouting velocity field, grouting pressure field, phase fraction field and slurry viscosity field of the current time step can be obtained. The above steps are repeated to advance the time step until the final set grouting time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures.

[0117] As an optional implementation, during the grouting simulation, the simulated three-dimensional flow field, pressure distribution and time series data can be visualized in the form of graphs. At the same time, the velocity field, concentration field and slurry diffusion morphology in the simulation process can be animated. The user can intuitively observe the entire grouting process and facilitate the analysis of the simulated grouting pressure and diffusion changes.

[0118] Example 2

[0119] In one or more embodiments, a nonlinear coupled simplified fracture filling hydrodynamic grouting simulation system is disclosed, comprising:

[0120] Parameter initialization module, used to build the geometric model of the area to be simulated, divide the fluid calculation grid for the geometric model, and initialize the model parameters;

[0121] The velocity simulation module is used to construct the fluid continuity equation and momentum equation based on the initialized model parameters. In the momentum equation, the Darcy-Forchheimer law is used to describe the relationship between pressure gradient and velocity, and the viscous permeability coefficient and inertial permeability coefficient are introduced. Based on the discretized fluid continuity equation and momentum equation, the grouting pressure and grouting velocity at the current time step are calculated;

[0122] The concentration simulation module is used to construct the concentration field equation according to the velocity field of the current time step, and obtain the slurry concentration distribution and grouting velocity of the current time step based on the coupling solution of the discretized concentration field equation and momentum equation;

[0123] Phase fraction simulation module, which is used to construct the phase fraction equation according to the grouting velocity at the current time step and obtain the slurry diffusion morphology in the water-rich filling fracture at the current time step;

[0124] By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained;

[0125] The iterative calculation module is used to repeat the above process for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures.

[0126] It should be noted that the specific implementation of the above modules is the same as that in Example 1 and will not be described in detail.

[0127] Example 3

[0128] In one or more embodiments, a terminal device is disclosed, which includes a processor and a memory, wherein the processor is used to implement instructions; the memory is used to store multiple instructions, and the instructions are suitable for being loaded by the processor and executed by the nonlinear coupling simplified dynamic water grouting simulation method for filling fractures described in Example 1.

[0129] It should be understood that in this embodiment, the processor may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), off-the-shelf field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0130] The memory may include a read-only memory and a random access memory, and provides instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0131] During implementation, each step of the above method may be completed by an integrated logic circuit of hardware in a processor or by instructions in the form of software.

[0132] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without any creative work are still within the scope of protection of the present invention.

Claims

1. A simplified nonlinear coupling method for simulating dynamic water grouting for filling fractures, characterized in that: include: Construct a geometric model of the area to be simulated, divide the fluid calculation grid into the geometric model, and initialize the model parameters; Constructing a fluid continuity equation and a momentum equation based on the initialized model parameters. In the momentum equation, the Darcy-Forchheimer law is used to describe the relationship between pressure gradient and velocity, and the viscous permeability coefficient and the inertial permeability coefficient are introduced. Based on the discretized fluid continuity equation and momentum equation, the grouting pressure and grouting velocity of the current time step are calculated; the concentration field equation is constructed according to the velocity field of the current time step, and the slurry concentration distribution and grouting velocity of the current time step are obtained based on the coupled solution of the discretized concentration field equation and momentum equation; According to the grouting velocity of the current time step, the phase fraction equation is constructed to obtain the slurry diffusion pattern in the water-rich filling fracture at the current time step; By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained; Repeat the above process for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures; The momentum equation is specifically: in, represents the multiphase velocity, represents density, represents the gradient operator, which is used to describe the change of vector field or scalar field in space. represents the dynamic viscosity coefficient, represents the viscous permeability coefficient, represents the inertial permeability coefficient, represents the action of body force on the fluid, represents the unit tensor, represents the source term; is the interpolation function, 0≤ , is the Reynolds number of the grid area.

2. A nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: The interpolation function The specific values ​​are: when hour, , at this time, viscosity dominates; when hour, , inertia dominates at this time; On this basis, when viscosity dominates and inertia dominates, the specific value of Re is set according to actual needs; when When taking other intermediate values, Smoothly transition between 0 and 1.

3. The nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: The concentration field equation is constructed based on the velocity field of the current time step, specifically: ； in, Indicates the concentration of the slurry, is the concentration diffusion coefficient, Indicates the source of additional slurry concentration during the grouting process, It refers to the part of the slurry that is consumed or reduced due to some physical or chemical mechanism during the flow and diffusion process.

4. The nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: The phase fraction equation is constructed according to the grouting velocity of the current time step, specifically: ； in, represents the slurry phase fraction, Represents multiphase velocity.

5. The nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: The discrete injection time transmission equation is specifically: ； Among them, T is the injection duration at the current moment, represents the multiphase velocity, The water phase fraction, represents the slurry phase fraction, Represents the proportionality coefficient, Indicates the relative movement speed between the slurry phase and the water phase.

6. The nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: Construct a geometric model of the area to be simulated, specifically: Obtain the lithology, filling fracture geometry, filling medium type and distribution data of the area to be simulated, and construct a three-dimensional geometric model of water-rich filling fractures.

7. The nonlinear coupled simplified dynamic water grouting simulation method for filling fractures according to claim 1, characterized in that: Also includes: The three-dimensional flow field, pressure distribution and time series data obtained by simulation are visualized, and the velocity field, concentration field and slurry diffusion morphology during the simulation process are animated.

8. A nonlinear coupled simplified fracture filling water dynamic grouting simulation system, characterized in that: include: Parameter initialization module, used to build the geometric model of the area to be simulated, divide the fluid calculation grid for the geometric model, and initialize the model parameters; The velocity simulation module is used to construct the fluid continuity equation and momentum equation based on the initialized model parameters. In the momentum equation, the Darcy-Forchheimer law is used to describe the relationship between pressure gradient and velocity, and the viscous permeability coefficient and inertial permeability coefficient are introduced. Based on the discretized fluid continuity equation and momentum equation, the grouting pressure and grouting velocity at the current time step are calculated; The concentration simulation module is used to construct the concentration field equation according to the velocity field of the current time step, and obtain the slurry concentration distribution and grouting velocity of the current time step based on the coupling solution of the discretized concentration field equation and momentum equation; Phase fraction simulation module, which is used to construct the phase fraction equation according to the grouting velocity at the current time step and obtain the slurry diffusion morphology in the water-rich filling fracture at the current time step; By constructing a discrete injection time transmission equation, the slurry injection duration of the current time step is obtained; Iterative calculation module, used to repeat the above process for each time step until the set time step is reached to complete the simulation of dynamic water grouting of water-rich filling fractures; The momentum equation is specifically: in, represents the multiphase velocity, represents density, represents the gradient operator, which is used to describe the change of vector field or scalar field in space. represents the dynamic viscosity coefficient, represents the viscous permeability coefficient, represents the inertial permeability coefficient, represents the action of body force on the fluid, represents the unit tensor, represents the source term; is the interpolation function, 0≤ , is the Reynolds number of the grid area.

9. A terminal device comprising a processor and a memory, wherein the processor is used to implement instructions; the memory is used to store multiple instructions, characterized in that: The instructions are suitable for being loaded by a processor and executed by the nonlinear coupled simplified fracture filling water dynamic grouting simulation method according to any one of claims 1 to 7.

Images