Karst coupling medium network three-dimensional reconstruction method and system

Abstract

This invention relates to the field of karst media modeling and seepage simulation, and provides a method and system for three-dimensional reconstruction of karst coupled media networks. The method includes: acquiring the characteristics of dissolution pores in actual karst geological conditions and generating an equivalent dissolution pore matrix model; acquiring the characteristics of dissolution cavities in actual karst geological conditions and generating a three-dimensional equivalent dissolution cavity media model; acquiring the characteristics of fractures in actual karst geological conditions, generating an original equivalent three-dimensional fracture network model, and trimming the fracture portions outside the characterizing unit cell model to generate a three-dimensional fracture equivalent media model; generating a three-dimensional equivalent karst coupled media network based on the equivalent dissolution pore matrix, the three-dimensional equivalent dissolution pore media, and the three-dimensional equivalent fracture media model; and performing meshing processing on the three-dimensional equivalent karst coupled media network to achieve fluid dynamics analysis and simulation. This invention accurately reflects the equivalent distribution and seepage laws of karst media.

Description

Technical Field

[0001] This invention relates to the field of karst media modeling and seepage simulation technology, and in particular to a three-dimensional reconstruction method and system for karst coupled media networks. Background Technology

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

[0003] Karst media are typically multi-scale coupled seepage systems composed of dissolution pores, dissolution cavities, and fracture systems. Their complex spatial structure and seepage characteristics directly control a series of key processes in karst areas, including groundwater transport, resource development, engineering safety, and ecological protection. Dissolution pores are usually small and dispersed, forming the main fluid storage space; dissolution cavities are larger in scale and irregular in shape, often serving as local dominant channels; while fracture systems form penetrating seepage paths, controlling the direction and rate of regional water flow. These three elements do not exist in isolation but interact through strong fluid exchange and pressure transmission, jointly regulating the macroscopic seepage behavior and mechanical response of karst media. Traditional hydrogeological models often simplify each medium into a single pore or fracture system, or only consider the coupling of two media, failing to accurately depict the heterogeneous, anisotropic, and non-equilibrium flow characteristics under the synergistic effect of the three elements. This leads to significant errors in practical engineering applications, severely restricting the accurate design and safety control of major engineering projects.

[0004] Existing technologies mostly focus on idealized descriptions of pore-fracture dual media, lacking explicit characterization and integration of the important structure of dissolution pores, making it difficult to truly reflect the typical structural characteristics of karst media. In addition, the various structures such as dissolution pores, dissolution cavities, and fractures in natural karst media exhibit highly heterogeneous, multi-scale, and strongly coupled distribution characteristics in three-dimensional space, making it difficult to reconstruct their actual seepage environment using only two-dimensional models or simplified geometric assumptions.

[0005] While existing technologies disclose numerical analysis of dissolution pores obtained by scanning rock samples using multi-source data acquisition techniques such as CT and acoustic imaging, they suffer from challenges in solving flow problems with such complex structures. These challenges include large computational scale, difficulty in convergence, and low efficiency. Furthermore, the segmentation and extraction of media at different scales in the images are easily limited by noise and resolution. Additionally, the fusion and representation of diverse structures in three-dimensional space and the generation of meshes are highly complex. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a method and system for three-dimensional reconstruction of karst coupled media networks. This invention uses multiple methods, including nuclear magnetic resonance, CT scanning, scanning electron microscopy, and well logging, to identify karst media parameters. Combined with numerical simulation methods, it reconstructs and quantifies the three-dimensional network of dissolution pores, dissolution voids, and fractures. This allows for the rapid, accurate, and efficient construction of an equivalent three-dimensional network of dissolution pores-dissolution voids-fractures coupled media. Furthermore, the data volume is quantified, enabling a more accurate simulation of the heterogeneity and anisotropy of karst media flow.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides a method for three-dimensional reconstruction of karst coupled media networks.

[0009] A method for three-dimensional reconstruction of karst coupled media networks, comprising:

[0010] Based on actual karst geological conditions and the size of the characterizing unit, a characterizing unit model is constructed;

[0011] To obtain the characteristics of dissolution pores in actual karst geological conditions, and to generate an equivalent dissolution pore matrix model in the characterization unit model;

[0012] To obtain the characteristics of dissolution cavities in actual karst geological conditions, and to characterize the unit cell size to generate a three-dimensional equivalent medium model of dissolution cavities;

[0013] The fracture characteristics in actual karst geological conditions are obtained to characterize the unit cell size and generate the original equivalent three-dimensional fracture network model. The fracture part outside the characterizing unit cell model is then trimmed, and the remaining fracture network is the three-dimensional fracture equivalent medium model.

[0014] The equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, and the three-dimensional fracture equivalent medium model is defined as the fracture phase field. A global coupling control function is defined, and the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, each phase field competes, repels, and merges with each other, and finally forms a composite phase field, which is the three-dimensional equivalent karst coupling medium network.

[0015] The three-dimensional equivalent karst coupled medium network is meshed and a hybrid physical numerical model is established to realize fluid dynamics analysis and simulation.

[0016] Furthermore, the method for obtaining the dissolution pore characteristics in actual karst geological conditions and generating an equivalent dissolution pore matrix model in the characterization unit model includes: constructing a characterization unit model with the characterization unit size; generating several equivalent dissolution pores based on the obtained dissolution pore characteristics; determining the distribution range of dissolution pore size through the average equivalent radius and the distribution law of dissolution pore characteristics; determining the number of dissolution pores through porosity; and generating an equivalent dissolution pore matrix model; wherein the dissolution pore characteristics include porosity, equivalent radius, and the distribution law of dissolution pore characteristics.

[0017] Furthermore, the method for obtaining the characteristics of dissolution cavities in actual karst geological conditions to characterize the unit cell size and generate a three-dimensional equivalent medium model of dissolution cavities includes: randomly generating a spatial coordinate point in the characterizing unit cell model; generating a dissolution cavity based on the obtained dissolution cavity characteristics with the spatial coordinate point as the center; determining the distribution range of dissolution pore size through the average equivalent radius and the distribution law of dissolution cavity characteristics; determining the number of dissolution cavities through the porosity; determining the equivalent morphology of dissolution cavities through the morphology of dissolution cavities; and generating a three-dimensional equivalent medium model of dissolution cavities. The dissolution cavity characteristics include the morphology of dissolution cavities, the porosity, the equivalent radius, and the distribution law of dissolution cavity characteristics.

[0018] Furthermore, the method for obtaining fracture characteristics in actual karst geological conditions to characterize the unit cell size and generate an original equivalent three-dimensional fracture network model includes: randomly generating a spatial coordinate point in the characterizing unit cell model; generating an equivalent fracture based on the obtained fracture characteristics with the spatial coordinate point as the center; repeating the equivalent fracture generation process to generate the original equivalent three-dimensional fracture network model; wherein, the fracture characteristics include at least fracture rate, fracture aperture, fracture attitude, equivalent length, and fracture characteristic distribution law; the fracture attitude includes the average fracture strike and average dip angle, and the equivalent fracture length is characterized by the average equivalent length.

[0019] Furthermore, the method for meshing the three-dimensional equivalent karst coupled medium network includes: using a free tetrahedral meshing method to mesh the three-dimensional equivalent karst coupled medium network, selecting geometric domains representing dissolution pores and fissures, and independently refining and controlling specific pores or single fissures by adjusting the maximum and minimum values ​​of the range of the number of unit meshes.

[0020] Furthermore, the introduction of phase field dynamics equations controls the evolution of each phase field, enabling them to reach a stable equilibrium state under the constraints of the coupled control function. Through iterative calculations, the phase fields compete, repel, and merge with each other, ultimately forming a composite phase field; this is expressed by the following formula:

[0021]

[0022] C(x) = α P(x) + β V(x)+ γ F(x)

[0023] in, Indicates a composite phase field; Represents any one of the fields P, V, and F; λ It is the relaxation rate, which controls the speed of evolution; M ( x C(x) is a mask field used to protect specific regions that are not intended to be altered; C(x) is the coupling control function. α , β , γ All are weights; P(x) is the equivalent dissolution pore matrix model represented by the three-dimensional scalar field function; V(x) is the equivalent medium model of three-dimensional dissolution pores represented by the three-dimensional scalar field function; F(x) is the equivalent medium model of three-dimensional fractures represented by the three-dimensional scalar field function.

[0024] A second aspect of the present invention provides a three-dimensional reconstruction system for karst coupled media networks.

[0025] A three-dimensional reconstruction system for karst coupled media networks, comprising:

[0026] The characterization unit model construction module is configured to construct a characterization unit model based on actual karst geological conditions and characterization unit size.

[0027] The equivalent dissolution pore matrix model construction module is configured to: acquire the dissolution pore characteristics in actual karst geological conditions and generate an equivalent dissolution pore matrix model in the characterization unit model;

[0028] The three-dimensional dissolution cavity equivalent medium model construction module is configured to: acquire the characteristics of dissolution cavities in actual karst geological conditions, and generate a three-dimensional dissolution cavity equivalent medium model to characterize the unit cell size;

[0029] The three-dimensional fracture equivalent medium model construction module is configured to: acquire fracture characteristics in actual karst geological conditions, generate an original equivalent three-dimensional fracture network model to characterize the unit cell size, and trim the fracture part outside the characterizing unit cell model. The remaining fracture network is the three-dimensional fracture equivalent medium model.

[0030] The three-dimensional equivalent karst coupled medium network construction module is configured as follows: the equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, the three-dimensional fracture equivalent medium model is defined as the fracture phase field, a global coupling control function is defined, the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function, and through iterative calculation, the phase fields compete, repel and merge with each other, and finally form a composite phase field, which is the three-dimensional equivalent karst coupled medium network;

[0031] The model processing module is configured to mesh the three-dimensional equivalent karst coupled medium network and establish a hybrid physical numerical model to achieve fluid dynamics analysis and simulation.

[0032] A third aspect of the present invention provides a computer device comprising:

[0033] A processor, adapted to execute computer programs;

[0034] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in the three-dimensional reconstruction method for karst coupled media networks as described in the first aspect above.

[0035] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program adapted to be loaded by a processor and to execute the steps in the three-dimensional reconstruction method for karst coupled media networks as described in the first aspect above.

[0036] The fifth aspect of the present invention provides a computer program product or computer program.

[0037] This invention provides a computer program product or computer program comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the steps in the karst coupling medium network three-dimensional reconstruction method as described in the first aspect above.

[0038] Compared with the prior art, the beneficial effects of the present invention are:

[0039] This invention couples and quantifies the three-dimensional dissolution pore equivalent matrix, the three-dimensional dissolution cavity equivalent medium network, and the three-dimensional fracture equivalent medium network. This allows for the rapid, accurate, and efficient construction of a three-dimensional equivalent karst coupled medium network, accurately reflecting the distribution and interaction of the internal media of the karst. Subsequently, the three-dimensional data volume is quantified and subjected to fluid dynamics analysis and simulation.

[0040] Based on the seepage physical process of fluid in dissolution porous matrix, dissolution pores, fractured media and coupled media network, this invention establishes the basic control equations for seepage in coupled media. The model parameters can be set and verified using existing seepage simulation software to perform simulation calculations of the hybrid physical model, thereby enabling the analysis and simulation of seepage mechanics. Attached Figure Description

[0041] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0042] Figure 1 This is a flowchart of the three-dimensional reconstruction method of karst coupled media network in an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the method for simulating and generating a three-dimensional equivalent karst coupled medium network in an embodiment of the present invention;

[0044] Figure 3 This is a schematic diagram of the equidistant division of the characterizing unit in an embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram of the equivalent matrix model of three-dimensional dissolution pores in an embodiment of the present invention;

[0046] Figure 5(a) is a schematic diagram of the equivalent medium network model of the three-dimensional dissolution pores of the sphere in the embodiment of the present invention;

[0047] Figure 5(b) is a schematic diagram of the equivalent medium network model of the three-dimensional dissolution pores of the ellipsoid in the embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of the three-dimensional fracture equivalent medium network model in an embodiment of the present invention;

[0049] Figure 7 This is a schematic diagram of the three-dimensional fracture equivalent medium network model after trimming in an embodiment of the present invention;

[0050] Figure 8(a) is a schematic diagram of the three-dimensional equivalent karst coupling medium network model of the sphere in an embodiment of the present invention;

[0051] Figure 8(b) is a schematic diagram of the three-dimensional equivalent karst coupling medium network model of the ellipsoid in an embodiment of the present invention;

[0052] Figure 9(a) is a schematic diagram of the meshing of the network model containing the equivalent coupling medium of the sphere in an embodiment of the present invention;

[0053] Figure 9(b) is a schematic diagram of the meshing of the network model containing an ellipsoidal equivalent coupling medium in an embodiment of the present invention;

[0054] Figure 10(a) is a schematic diagram of the X-direction seepage simulation model of the equivalent coupled medium network in an embodiment of the present invention;

[0055] Figure 10(b) is a schematic diagram of the Y-direction seepage simulation model of the equivalent coupled medium network in an embodiment of the present invention;

[0056] Figure 10(c) is a schematic diagram of the Z-axis seepage simulation model of the equivalent coupled medium network in an embodiment of the present invention;

[0057] Figure 11 This is a structural diagram of the karst coupling medium network three-dimensional reconstruction system in an embodiment of the present invention;

[0058] Figure 12 This is a structural diagram of the computer device in an embodiment of the present invention. Detailed Implementation

[0059] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0060] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. 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 invention pertains.

[0061] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. 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.

[0062] Figure 1 This is a flowchart illustrating the three-dimensional reconstruction method of karst coupled media network according to an embodiment of the present invention; see reference. Figure 1 The method includes:

[0063] Based on actual karst geological conditions and the size of the characterizing unit, a characterizing unit model is constructed;

[0064] To obtain the characteristics of dissolution pores in actual karst geological conditions, and to generate an equivalent dissolution pore matrix model in the characterization unit model;

[0065] To obtain the characteristics of dissolution cavities in actual karst geological conditions, and to characterize the unit cell size to generate a three-dimensional equivalent medium model of dissolution cavities;

[0066] The fracture characteristics in actual karst geological conditions are obtained to characterize the unit cell size and generate the original equivalent three-dimensional fracture network model. The fracture part outside the characterizing unit cell model is then trimmed, and the remaining fracture network is the three-dimensional fracture equivalent medium model.

[0067] The equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, and the three-dimensional fracture equivalent medium model is defined as the fracture phase field. A global coupling control function is defined, and the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, each phase field competes, repels, and merges with each other, and finally forms a composite phase field, which is the three-dimensional equivalent karst coupling medium network.

[0068] The three-dimensional equivalent karst coupled medium network is meshed and a hybrid physical numerical model is established to realize fluid dynamics analysis and simulation.

[0069] This invention identifies karst medium parameters and combines numerical simulation methods to couple, reconstruct, and quantify a three-dimensional network of dissolution pores, dissolution cavities, and fractures. This enables the rapid, accurate, and efficient construction of an equivalent network of a three-dimensional coupled medium of dissolution pores, dissolution cavities, and fractures. Furthermore, by quantifying the data volume, it can more accurately simulate and characterize the heterogeneity and anisotropy of karst media during seepage.

[0070] Figure 2 This is a schematic diagram of the method for simulating and generating a three-dimensional equivalent karst coupled media network in an embodiment of the present invention; see reference. Figure 2 This includes the following steps:

[0071] (1) Construct a characterization unit model based on actual geological conditions;

[0072] In this embodiment, based on the micro-fine characterization unit size and the macroscopic karst medium size, combined with Figure 3 ( Figure 3 The white dots represent the imaging response of mineral components to X-rays, while the dark gray and black areas represent fissures and solution pores. The shape and size data of the karst characterization unit model are determined; the characterization unit model is typically a cube; the cube's size data includes the side length. La The specific shape and size data are determined according to actual needs. Additionally, more complex model shapes can be created based on actual geological conditions.

[0073] (2) Obtain the characteristics of dissolution pores in actual karst geological conditions, and generate a three-dimensional equivalent matrix model of dissolution pores in the characterization unit model;

[0074] In this embodiment, the types of dissolution pores can be dissolution-type pores, intergranular dissolution pores, dissolution fractures, diagenetic shrinkage fractures, and intergranular fractures. Dissolution pore characteristics include at least porosity, equivalent radius, and their distribution patterns. Dissolution pores are typically the smallest in scale but provide the main storage space; fluid flow is slow, primarily through diffusion. Porosity is established using geostatistics. ε p ) and the permeability field, where the permeability field is determined by permeability ( χ The data were constructed based on nuclear magnetic resonance, scanning electron microscopy, and CT testing.

[0075] In this embodiment, the process of generating an equivalent dissolved pore matrix model in the characterization unit model is as follows: based on the obtained porosity, equivalent radius, and their distribution patterns, porosity characteristics are assigned to the characterization unit; combined with the permeability obtained from experimental tests, permeability characteristics are assigned to the characterization unit, and a permeability field is constructed; experimental tests include nuclear magnetic resonance, scanning electron microscopy, and CT tests, wherein the CT test distinguishes the permeability characteristics of dissolved pores and dissolved voids using threshold segmentation technology, such as... Figure 4 As shown ( Figure 4 The black dots are calcified dissolution pores.

[0076] (3) Obtain the characteristics of dissolution cavities in actual karst geological conditions, and generate a three-dimensional equivalent medium model of dissolution cavities in the characterization unit model;

[0077] In this embodiment, the type of dissolution pores is a dissolution pore with an equivalent diameter between 5 and 500 mm. The characteristics of dissolution pores include at least the pore morphology, porosity, equivalent radius, and distribution pattern. Referring to Figures 5(a) and 5(b), the morphology of dissolution pores can generally be equivalent to two main categories: spheres and ellipsoids. They are relatively large in scale and serve as important storage spaces and high-speed flow channels. Their spatial distribution can be discontinuous or clustered. The number of dissolution pores in the model body is determined by the porosity. ψ v Configure; the size of the dissolution cavity is determined by the equivalent radius. Rv The distribution pattern is controlled, which can be a normal distribution, a random distribution, etc.

[0078] Specifically, taking a sphere as an example, the process of generating a three-dimensional equivalent medium model of dissolution cavities is as follows:

[0079] Considering the boundary effects of the coupled network model, a 0.01m full matrix region is reserved at the boundary when generating the equivalent medium model of dissolution pores in the dissolution pore matrix.

[0080] Using the reduced boundary range as the region, the center point coordinates of the dissolution holes are randomly generated. Combined with the equivalent radius of the spheres, the overlap relationship between the spheres and the contact relationship between the spheres and the boundary are checked. When the spheres overlap with the boundary, the spheres are regenerated and the dissolution hole generation process is repeated.

[0081] Set the height of the spherical crown to Based on the height of the spherical crown Then calculate the volume of the overlapping spherical cap. The calculation equation is as follows:

[0082]

[0083]

[0084] In the formula, Let m be the volume of the spherical caps of spheres a and b. 3 ; Let be the height of the spherical caps of spheres a and b, in meters. Let be the radii of spheres a and b, in meters.

[0085] Remove overlapping portions from the model, check and adjust the model's porosity to ensure that the model's porosity and seepage characteristics remain valid. The calculation formula is as follows:

[0086]

[0087] in, This represents the volume of the spherical cap of sphere a after removing the overlapping portion; This represents the volume of the spherical cap of sphere b after removing the overlapping portion.

[0088] Then, an equivalent medium network of dissolution cavities is created based on the generated spheres, with each pair of spheres... and sphere A cavity is considered a connected dissolution cavity if it satisfies the following equations.

[0089]

[0090] In the formula, d ab Let be the distance between spheres a and b, in meters (m). This represents the scaling factor, used to control the connection threshold.

[0091] Finally, a visual model of the equivalent medium of dissolved cavities was created based on the spherical equation and the system of linear equations. L ( t ).

[0092]

[0093]

[0094] In the formula, ( x a , x b , x c (a sphere) a The coordinates of the center point; C a and C b Let a and b be the equations of their surfaces.

[0095] (4) Obtain the fracture characteristics in actual karst geological conditions, and generate a three-dimensional fracture equivalent medium model within the characterization unit domain through a discrete fracture network;

[0096] In this embodiment, the fracture characteristics in actual karst geological conditions can be obtained through laser scanning, borehole inspection, seismic geophysical exploration, etc.; the fracture characteristics include at least fracture rate, fracture aperture, fracture attitude, equivalent length, and distribution pattern; the fracture attitude includes the mean dip angle. α Tendency mean β The crack length is obtained by taking the mean of the equivalent crack length or the mean of the equivalent crack radius. R c Characterization; number of fractures N c The grouping settings can be configured, and the distribution of fracture parameters can be normal, random, or other patterns.

[0097] Based on the actual karst fissure morphology, the generated fissures are mainly disc-shaped.

[0098] Specifically, the process of generating a three-dimensional fracture equivalent medium network model is as follows:

[0099] The center coordinates generated within the characterization unit domain are: , radius is The random disk crack, based on the Euler angle principle, defines the pitch angle and yaw angle as the tilt angle, respectively. α ,tendency β Rotate the fracture coordinate system around the z-axis to the fracture dip direction, and the transformation equation is as follows;

[0100]

[0101] The rotated coordinate system is further rotated around the y-axis until the original coordinate system aligns with the fracture dip. The calculation equations and the overall rotation matrix are as follows:

[0102]

[0103]

[0104] Rotation matrix Original coordinates in the global coordinate system Multiplication transformation yields the disk crack model in Cartesian coordinates;

[0105] Based on the fracture aperture A single three-dimensional random fracture model with a complete parameter system is obtained by translating along the normal direction. Then, the original equivalent three-dimensional fracture network model is obtained through a loop language, such as... Figure 6 As shown.

[0106] Combination Figure 7 The characterization unit model and the original equivalent three-dimensional fracture network model are saved as two sets of spatial coordinate data respectively.

[0107] By detecting the overlap of spatial coordinate data, the fracture network that intersects with the characterization unit model in the original equivalent 3D fracture network model is retained, which is the trimmed 3D fracture equivalent medium model, such as... Figure 7 As shown.

[0108] (5) Based on the constructed equivalent dissolution pore matrix model, three-dimensional dissolution pore equivalent medium model, and three-dimensional fracture equivalent medium model, a three-dimensional dissolution pore matrix-dissolution pore medium-fracture medium coupled network model is generated, namely, a three-dimensional equivalent karst coupled medium network.

[0109] The equivalent dissolved pore matrix model is defined as the background phase field (PF), which is represented by a three-dimensional scalar field function P(x), and its range [0,1] represents the continuous transition from intact rock (0) to fully dissolved pore matrix (1);

[0110] The equivalent medium model of the three-dimensional dissolution pore is defined as the pore phase field (VF), which is represented by a three-dimensional scalar field function V(x). Its value is 1 inside the pore and 0 outside, and there is a smooth transition zone at the interface.

[0111] The three-dimensional fracture equivalent medium model is defined as the fracture phase field (FF), which is represented by a three-dimensional scalar field function F(x). Its value is 1 inside the fracture and 0 outside. A smooth transition zone also exists at the interface.

[0112] Define a global coupling control function C(x), which determines the competition and symbiotic relationship between different phase fields at any point x in space. C(x) is generated based on geological rules and uses a weighted summation form: C(x) = α ×P(x) + β ×V(x)+ γ ×F(x) is obtained, where the weights are... α、β , γ Location-dependent, characterizing the geological preferences of a region.

[0113] The evolution of each phase field is controlled by a phase field dynamic equation, which, under the constraint of the coupling function C(x), reaches a stable equilibrium state, and the evolution rules are constructed as follows:

[0114]

[0115] in, Indicates a composite phase field; Represents any one of the fields P, V, and F; λ It is the relaxation rate, which controls the speed of evolution; M ( x A mask field is a field used to protect specific areas that are not intended to be altered.

[0116] By iteratively calculating the above rules, the phase fields compete, repel, and merge with each other, ultimately forming a stable composite phase field with natural boundaries. This is a three-dimensional equivalent karst coupling medium network.

[0117] (6) The three-dimensional dissolution pore-dissolution cavity-crack equivalent coupled medium network is meshed and a hybrid numerical model is established to realize seepage mechanics analysis and simulation.

[0118] In this embodiment, the meshing process of the three-dimensional equivalent coupled medium network typically employs the free tetrahedral mesh generation method, which exhibits excellent adaptability to complex and irregular geometric shapes and can effectively characterize the intricate spatial configuration relationships between dissolution pores, dissolution voids, and fractures. To achieve high-fidelity simulation, differentiated mesh refinement strategies are required for the randomly generated dissolution void and fracture networks of varying scales. This regional refinement approach stems from the distinct geometric characteristics and physical effects of different media: the dissolution pore matrix typically constitutes the background continuous phase, allowing for a relatively large mesh scale to control the overall computational scale; while dissolution voids, as important reservoir spaces and flow channels, require finer meshes to capture internal flow details due to their complex morphology; fractures, with their extremely high permeability, become the dominant seepage channels, but their opening is extremely small, necessitating the application of dense meshes to their walls and surrounding matrix to accurately resolve their strong pressure gradients and significant local effects.

[0119] Specifically, after completing the construction of the geometric coupling model, geometric domains representing dissolution pores and fissures are selected respectively. By specifically adjusting the maximum and minimum values ​​of the range of the number of unit grids, independent and refined control of specific pores or single fissures can be achieved.

[0120] The core advantage of this targeted meshing method lies in its ability to concentrate computational resources in areas where critical physical processes occur. This significantly improves the simulation accuracy of transport behavior in control pores and flow-guiding fissures without excessively increasing the overall computational load. This ensures accurate analysis of local flow and stress fields, avoiding the risk of key physical phenomena being diluted or ignored due to mesh coarsening. The resulting unstructured mesh model not only geometrically accurately characterizes the complex spatial structure of the multi-medium coupled system but also optimizes computational resource allocation, laying a reliable foundation for subsequent seepage simulations and contributing to a deeper understanding of the complex seepage mechanisms in such coupled media at multiple scales.

[0121] In this embodiment, based on the different physical processes of dissolution pores, dissolution voids, and fractured media, different flow equations are defined for the equivalent dissolution pore matrix model, the three-dimensional dissolution void equivalent medium model, and the three-dimensional fracture equivalent medium model; by setting model parameters and verifying them, the simulation calculation of the hybrid physical model can be performed.

[0122] Specifically, it is assumed that in a karst medium, fluid flows into fissures from dissolution pores and cavities, and flows in the form of fissure flow. Furthermore, there is an exchange between the fluid in the dissolution pores and the fluid in the fissures and cavities, and the fluid flows within the fissures and cavities. However, there is no fluid flow within the dissolution pores, which only provide a water source for the dissolution pores and fissures.

[0123] Based on the physical process of fluid seepage in a dissolving porous medium, the flow equations for the three-dimensional equivalent medium model of a dissolving porous medium are defined as follows:

[0124]

[0125] Based on the physical process of fluid seepage in fractured media, the flow equations for a three-dimensional fractured equivalent medium model are defined as follows:

[0126]

[0127] Based on the seepage physics of fluid in a dissolving porous matrix, the flow equations for an equivalent dissolving porous matrix model are defined as follows:

[0128]

[0129] Among them, in the governing equations, ρ The density of the fluid in the medium; k D represents absolute penetration. μ The coefficient of dynamic viscosity is given in Pa·s. -1 ; p The pressure exerted on the fluid in the aqueous medium, in MPa; , These represent the net outflow rate of the fluid in soluble porous media and fractured media, respectively, in kg·m³. -3 ; For gradient operators; For the source and sink terms of the dissolving porous medium, kg·m -3 ; The flow rate between the dissolution pore matrix and the dissolution pore medium per unit volume, expressed in kg·m³. -3 ·s -1 ; The flow rate between fractured media and cavitary media per unit volume, expressed in kg·m³. -3 ·s -1 ; t For time, s; Porosity; For source and sink terms of fractured media, kg·m -3 ; The flux density between the dissolved porous matrix and the fractured medium is expressed in kg·m³. -3 ·s -1 ; For the source and sink terms of dissolving the porous matrix, kg·m -3 ; The flow rate between the dissolved porous matrix, fractured media, and dissolved pore media is expressed in kg·m³. -3 ·s -1 ; denoted as porosity of the dissolved porous medium; ho, cr, and po respectively characterize the dissolved porous medium, fractured medium, and dissolved porous matrix.

[0130] Based on the seepage process of fluid in an equivalent coupled medium network of dissolution pores, dissolution voids, and fractures, the flow equation between fractures is defined as follows:

[0131]

[0132] Flow between fissures and dissolution cavities:

[0133]

[0134] Flow between fracture and dissolved pore matrix:

[0135]

[0136] in, Porosity of the dissolving porous medium This refers to the pressure exerted on the fluid in the water-bearing fractured medium. The absolute permeability of the fractured medium. r The equivalent radius length is in meters. The absolute permeability of the eroding porous medium. The pressure exerted on the fluid in a water-containing, eroded, porous medium. The absolute permeability of the dissolved porous matrix. This refers to the pressure exerted on the fluid within a matrix containing dissolved porous structures. Porosity of the dissolving porous medium The porosity of the dissolved porous matrix, The conductivity coefficient between the porous and fractured media. It represents the conductivity coefficient between the dissolved porous matrix and the fractured medium.

[0137] As a specific implementation method, the shape and size data of the representation unit model are defined. The model shape is set to a cube, and the model size data is defined as follows: model side length L a The value is 1.2m, and the bottom left corner is the coordinate of the origin, i.e. (0,0,0).

[0138] The characteristics of the dissolution pore matrix were defined based on porous media theory and the actual karst microstructure development characteristics of a certain study area, with the porosity set at 5%; the average radius of the dissolution pores was also determined. R p The value is set to 71 μm, and the distribution follows a Gaussian normal distribution. Figure 4 The above data forms the equivalent matrix model of the three-dimensional dissolution pores.

[0139] The characteristics of dissolution cavities were defined, using equivalent models of spheres and ellipsoids respectively; for clear drawing, the porosity was set to 2%; the equivalent radius of the spherical dissolution cavities was also determined. R vq The depth was set to 0.02m, and the distribution pattern followed a Gaussian normal distribution. Figures 5(a) and 5(b) show the three-dimensional equivalent medium network of dissolution cavities generated based on the above data.

[0140] Fracture features were set, with two groups of fractures defined, and the average dip angle of each group of fractures was specified. α The angle is 80°, with an average tendency. β The angles were set to 35° and 95° respectively, and the distribution pattern followed a normal distribution; the crack length was obtained by taking the mean of the equivalent lengths. R c Characterization was performed, set to 1m; number of cracks N c The total is set to 16 items, with 8 items in each group. Figure 7 Based on the above data, a trimmed three-dimensional fracture equivalent medium network is generated.

[0141] The generated dissolution pore matrix, dissolution cavity medium network, and fracture medium network were converted into vector data. Using the lower left corner coordinates (0,0,0) as the base point, dissolution pores, dissolution cavities, and fractures were generated and coupled in sequence to achieve the construction of a three-dimensional equivalent karst coupled medium network. Figures 8(a) and 8(b) show the generated three-dimensional equivalent karst coupled medium network models.

[0142] The generated three-dimensional equivalent karst coupled medium network was numerically meshed using a free tetrahedral mesh, as shown in Figures 9(a) and 9(b). Mesh refinement was applied to dissolution pores, fissures, and media intersections. Furthermore, a seepage field was applied to the model to calculate seepage in different directions within the coupled medium network. Figures 10(a), 10(b), and 10(c) illustrate the anisotropic simulation scheme for seepage in the coupled medium network.

[0143] This embodiment couples and numerically processes a three-dimensional karst porous medium, a three-dimensional karst cavity medium network, and a three-dimensional fracture medium network. This allows for the rapid, accurate, and efficient construction of a three-dimensional equivalent karst coupled medium network. The resulting data volume is then numerically processed and subjected to seepage simulation. This provides a model foundation for karst seepage research, rock mechanics simulation, pollution transport prediction, resource exploration and development, and optimization design and decision support. For example:

[0144] ① Seepage simulation: It can accurately characterize the complex flow behavior and pressure transmission effect of fluids in the matrix, high conductivity pores and fractures, and significantly improve the ability to predict groundwater flow and crossflow phenomena in oil and gas reservoir development.

[0145] ② Rock mechanics simulation: It can simulate and analyze how fractures and pores affect the deformation, failure mechanism and stress field distribution of rock mass under external loads, providing key insights for assessing wellbore stability, fracturing optimization and underground reservoir design;

[0146] ③ Pollution transport prediction: By considering the combined effects of dominant transport channels and matrix diffusion / dispersion, the spatiotemporal evolution of pollutants in the underground environment can be simulated more accurately, which can help environmental risk assessment and remediation.

[0147] ④ Resource exploration and development: This model, through quantitative characterization of complex reservoir spaces, can deepen the understanding of reservoir configuration and fluid distribution patterns, providing a basis for decision-making in optimizing drilling trajectories and improving recovery rates;

[0148] ⑤ Optimize design and decision support: Promote the scientific and refined development of related fields by providing high-fidelity digital reproduction of underground systems.

[0149] The above combination Figure 1 , Figure 2The method for three-dimensional reconstruction of karst coupled media network provided in the embodiments of the present invention has been described in detail. Next, the system for three-dimensional reconstruction of karst coupled media network provided in the embodiments of the present invention will be described in conjunction with the accompanying drawings.

[0150] Figure 11 This is a schematic diagram of the structure of a karst coupling medium network three-dimensional reconstruction system shown in an embodiment of the present invention, with reference to... Figure 11 The system described in this invention includes:

[0151] The characterization unit model construction module is configured to construct a characterization unit model based on actual karst geological conditions and characterization unit size.

[0152] The equivalent dissolution pore matrix model construction module is configured to: acquire the dissolution pore characteristics in actual karst geological conditions and generate an equivalent dissolution pore matrix model in the characterization unit model;

[0153] The three-dimensional dissolution cavity equivalent medium model construction module is configured to: acquire the characteristics of dissolution cavities in actual karst geological conditions, and generate a three-dimensional dissolution cavity equivalent medium model to characterize the unit cell size;

[0154] The three-dimensional fracture equivalent medium model construction module is configured to: acquire fracture characteristics in actual karst geological conditions, generate an original equivalent three-dimensional fracture network model to characterize the unit cell size, and trim the fracture part outside the characterizing unit cell model. The remaining fracture network is the three-dimensional fracture equivalent medium model.

[0155] The three-dimensional equivalent karst coupled medium network construction module is configured as follows: the equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, the three-dimensional fracture equivalent medium model is defined as the fracture phase field, a global coupling control function is defined, the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function, and through iterative calculation, the phase fields compete, repel and merge with each other, and finally form a composite phase field, which is the three-dimensional equivalent karst coupled medium network;

[0156] The model processing module is configured to mesh the three-dimensional equivalent karst coupled medium network and establish a hybrid physical numerical model to achieve fluid dynamics analysis and simulation.

[0157] In some embodiments, the characterization unit model construction module is specifically configured to: construct a characterization unit model based on the characterization unit size; generate several equivalent dissolution pores based on the acquired dissolution pore features; determine the distribution range of dissolution pore size through the average equivalent radius and the distribution law of dissolution pore features; determine the number of dissolution pores through porosity; and generate an equivalent dissolution pore matrix model; wherein the dissolution pore features include porosity, equivalent radius, and the distribution law of dissolution pore features.

[0158] In some embodiments, the three-dimensional dissolution cavity equivalent medium model construction module is specifically configured to: randomly generate a spatial coordinate point in the characterization unit model; generate a dissolution cavity based on the acquired dissolution cavity features, with the spatial coordinate point as the center; determine the distribution range of the dissolution pore size through the average equivalent radius and the distribution law of the dissolution cavity features; determine the number of dissolution pores through the porosity; determine the equivalent morphology of the dissolution cavity through the morphology of the dissolution cavity; and generate a three-dimensional dissolution cavity equivalent medium model; wherein, the dissolution cavity features include the morphology of the dissolution cavity, the porosity, the equivalent radius, and the distribution law of the dissolution cavity features.

[0159] In some embodiments, the three-dimensional fracture equivalent medium model construction module is specifically configured to: randomly generate a spatial coordinate point in the characterization unit model, and generate an equivalent fracture based on the acquired fracture features with the spatial coordinate point as the center; repeat the equivalent fracture generation process to generate the original equivalent three-dimensional fracture network model; wherein, the fracture features include at least fracture rate, fracture aperture, fracture attitude, equivalent length, and fracture feature distribution law; the fracture attitude includes the average fracture direction and average dip angle, and the equivalent fracture length is characterized by the average equivalent length.

[0160] In some embodiments, the model processing construction module is specifically configured to: perform meshing processing on the three-dimensional equivalent karst coupling medium network using the free tetrahedral meshing method, select geometric domains representing dissolution pores and fissures, and independently refine and control specific pores or single fissures by adjusting the maximum and minimum values ​​of the range of the number of unit meshes.

[0161] In some embodiments, the introduction of phase field dynamic equations to control the evolution of each phase field allows each phase field to reach a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, the phase fields compete, repel, and merge with each other, ultimately forming a composite phase field; expressed by the following formula:

[0162]

[0163] C(x) = α P(x) + β V(x)+ γ F(x)

[0164] in, Indicates a composite phase field; Represents any one of the fields P, V, and F; λ It is the relaxation rate, which controls the speed of evolution; M ( x C(x) is a mask field used to protect specific regions that are not intended to be altered; C(x) is the coupling control function. α , β , γ All are weights; P(x) is the equivalent dissolution pore matrix model represented by the three-dimensional scalar field function; V(x) is the equivalent medium model of three-dimensional dissolution pores represented by the three-dimensional scalar field function; F(x) is the equivalent medium model of three-dimensional fractures represented by the three-dimensional scalar field function.

[0165] According to embodiments of the present invention, the 3D reconstruction system for karst coupled media networks can correspond to the execution of the methods described in the embodiments of the present invention, and the above and other operations and / or functions of each module of the 3D reconstruction system for karst coupled media networks are respectively for implementing Figure 1 , Figure 2 For the sake of brevity, the corresponding processes of each method in the code will not be elaborated here.

[0166] See Figure 12 The diagram shows the structure of a computer device, which includes a processor, a communication interface, and a computer-readable storage medium. The processor, communication interface, and computer-readable storage medium are connected via a bus or other means. The communication interface is used to receive and send data. The computer-readable storage medium can be stored in the computer device's memory. The computer-readable storage medium stores computer programs, including program instructions, and the processor executes the program instructions stored in the computer-readable storage medium. The processor (or CPU, Central Processing Unit) is the computing and control core of the computer device, adapted to implement one or more instructions, specifically adapted to load and execute one or more instructions to achieve the corresponding steps in the embodiment of the karst coupling medium network three-dimensional reconstruction method.

[0167] This embodiment provides a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the processing system of the computer device.

[0168] Furthermore, this storage space also contains one or more instructions suitable for loading and execution by the processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM memory or non-volatile memory, such as at least one disk storage device; optionally, it can also be at least one computer-readable storage medium located remotely from the aforementioned processor.

[0169] In one embodiment, the computer-readable storage medium stores one or more instructions; the processor loads and executes one or more instructions stored in the computer-readable storage medium to implement the corresponding steps in the above-described embodiment of the karst coupling medium network three-dimensional reconstruction method.

[0170] This embodiment provides a computer program product or computer program that includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the corresponding steps in the above-described embodiment of the karst coupled media network three-dimensional reconstruction method.

[0171] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0172] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0173] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0174] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0175] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for three-dimensional reconstruction of karst coupled media networks, characterized in that, include: Based on actual karst geological conditions and the size of the characterizing unit, a characterizing unit model is constructed; To obtain the characteristics of dissolution pores in actual karst geological conditions, and to generate an equivalent dissolution pore matrix model in the characterization unit model; To obtain the characteristics of dissolution cavities in actual karst geological conditions, and to characterize the unit cell size to generate a three-dimensional equivalent medium model of dissolution cavities; The fracture characteristics in actual karst geological conditions are obtained to characterize the unit cell size and generate the original equivalent three-dimensional fracture network model. The fracture part outside the characterizing unit cell model is then trimmed, and the remaining fracture network is the three-dimensional fracture equivalent medium model. The equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, and the three-dimensional fracture equivalent medium model is defined as the fracture phase field. A global coupling control function is defined, and the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, each phase field competes, repels, and merges with each other, and finally forms a composite phase field, which is the three-dimensional equivalent karst coupling medium network. The three-dimensional equivalent karst coupled medium network is meshed and a hybrid physical numerical model is established to realize fluid dynamics analysis and simulation. The introduction of phase field dynamic equations controls the evolution of each phase field, enabling each phase field to reach a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, the phase fields compete, repel, and merge with each other, ultimately forming a composite phase field. The following formula is used to express this: C(x) = α P(x) + β V(x)+ γ F(x) in, Indicates the composite phase field; It represents any one of the fields P, V, and F; λ It is the relaxation rate, which controls the speed of evolution; M ( x C(x) is a mask field used to protect specific regions that are not intended to be altered; C(x) is the coupling control function. α , β , γ All are weights; P(x) is the equivalent dissolution pore matrix model represented by the three-dimensional scalar field function; V(x) is the equivalent medium model of three-dimensional dissolution pores represented by the three-dimensional scalar field function; F(x) is the equivalent medium model of three-dimensional fractures represented by the three-dimensional scalar field function.

2. The three-dimensional reconstruction method for karst coupled media networks according to claim 1, characterized in that, The method for obtaining the dissolution pore characteristics in actual karst geological conditions and generating an equivalent dissolution pore matrix model in a characterization unit model includes: constructing a characterization unit model with characterization unit size; generating several equivalent dissolution pores based on the obtained dissolution pore characteristics; determining the distribution range of dissolution pore size through the average equivalent radius and the distribution law of dissolution pore characteristics; determining the number of dissolution pores through porosity; and generating an equivalent dissolution pore matrix model. The dissolution pore characteristics include porosity, equivalent radius, and the distribution law of dissolution pore characteristics.

3. The three-dimensional reconstruction method for karst coupled media networks according to claim 1, characterized in that, The method for obtaining the characteristics of dissolution cavities in actual karst geological conditions to characterize the unit cell size and generate a three-dimensional equivalent medium model of dissolution cavities includes: randomly generating a spatial coordinate point in the characterizing unit cell model; generating a dissolution cavity based on the obtained dissolution cavity characteristics with the spatial coordinate point as the center; determining the distribution range of dissolution pore size through the average equivalent radius and the distribution law of dissolution cavity characteristics; determining the number of dissolution cavities through the dissolution porosity; determining the equivalent morphology of dissolution cavities through the dissolution pore morphology; and generating a three-dimensional equivalent medium model of dissolution cavities. The dissolution cavity characteristics include the dissolution pore morphology, dissolution porosity, equivalent radius, and the distribution law of dissolution cavity characteristics.

4. The three-dimensional reconstruction method for karst coupled media networks according to claim 1, characterized in that, The method for obtaining fracture characteristics in actual karst geological conditions to characterize unit cell size and generate an original equivalent three-dimensional fracture network model includes: randomly generating a spatial coordinate point in the characterizing unit cell model; generating an equivalent fracture based on the obtained fracture characteristics with the spatial coordinate point as the center; repeating the equivalent fracture generation process to generate the original equivalent three-dimensional fracture network model; wherein, the fracture characteristics include at least fracture rate, fracture aperture, fracture attitude, equivalent length, and fracture characteristic distribution law; the fracture attitude includes the average fracture strike and average dip angle, and the equivalent fracture length is characterized by the average equivalent length.

5. The three-dimensional reconstruction method for karst coupled media networks according to claim 1, characterized in that, The method for meshing the three-dimensional equivalent karst coupled medium network includes: using the free tetrahedral meshing method to mesh the three-dimensional equivalent karst coupled medium network, selecting geometric domains representing dissolution pores and fissures, and independently refining and controlling specific pores or single fissures by adjusting the maximum and minimum values ​​of the range of the number of unit meshes.

6. A three-dimensional reconstruction system for karst coupled media networks, characterized in that, include: The characterization unit model construction module is configured to construct a characterization unit model based on actual karst geological conditions and characterization unit size. The equivalent dissolution pore matrix model construction module is configured to: acquire the dissolution pore characteristics in actual karst geological conditions and generate an equivalent dissolution pore matrix model in the characterization unit model; The three-dimensional dissolution cavity equivalent medium model construction module is configured to: acquire the characteristics of dissolution cavities in actual karst geological conditions, and generate a three-dimensional dissolution cavity equivalent medium model to characterize the unit cell size; The three-dimensional fracture equivalent medium model construction module is configured to: acquire fracture characteristics in actual karst geological conditions, generate an original equivalent three-dimensional fracture network model to characterize the unit cell size, and trim the fracture part outside the characterizing unit cell model. The remaining fracture network is the three-dimensional fracture equivalent medium model. The three-dimensional equivalent karst coupled medium network construction module is configured as follows: the equivalent dissolution pore matrix model is defined as the background phase field, the three-dimensional dissolution pore equivalent medium model is defined as the pore phase field, the three-dimensional fracture equivalent medium model is defined as the fracture phase field, a global coupling control function is defined, the phase field dynamic equation is introduced to control the evolution of each phase field, so that each phase field reaches a stable equilibrium state under the constraint of the coupling control function, and through iterative calculation, the phase fields compete, repel and merge with each other, and finally form a composite phase field, which is the three-dimensional equivalent karst coupled medium network; The model processing module is configured to: mesh the three-dimensional equivalent karst coupled medium network and establish a hybrid physical numerical model to achieve fluid dynamics analysis and simulation; The introduction of phase field dynamic equations controls the evolution of each phase field, enabling each phase field to reach a stable equilibrium state under the constraint of the coupling control function. Through iterative calculation, the phase fields compete, repel, and merge with each other, ultimately forming a composite phase field. The following formula is used to express this: C(x) = α P(x) + β V(x)+ γ F(x) in, Indicates the composite phase field; It represents any one of the fields P, V, and F; λ It is the relaxation rate, which controls the speed of evolution; M ( x C(x) is a mask field used to protect specific regions that are not intended to be altered; C(x) is the coupling control function. α , β , γ All are weights; P(x) is the equivalent dissolution pore matrix model represented by the three-dimensional scalar field function; V(x) is the equivalent medium model of three-dimensional dissolution pores represented by the three-dimensional scalar field function; F(x) is the equivalent medium model of three-dimensional fractures represented by the three-dimensional scalar field function.

7. A computer device, characterized in that, A processor, adapted to execute computer programs; A computer-readable storage medium storing a computer program, which, when executed by the processor, implements the steps of the three-dimensional reconstruction method for karst coupled media networks as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program adapted to be loaded by a processor and to execute the steps of the three-dimensional reconstruction method for karst coupled media networks as described in any one of claims 1-5.

9. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps in the three-dimensional reconstruction method for karst coupled media networks as described in any one of claims 1-5.

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