Analogue simulation method based on 3D printing fracture-cavity model, storage medium and equipment

Abstract

The invention relates to an analogue simulation method based on a 3D printing fracture-cavity model, a storage medium and equipment, and the method comprises the steps: generating an overall boundary geometry based on a 3D printing fracture-cavity model data body in an STL format, storing the overall boundary geometry as a file in a poly data format, and enabling data items of the file in the poly data format to comprise node data, surface data, cavity data and partition data; a piecewise linear structure method is adopted to describe a boundary geometry, then a TetGen algorithm is utilized to carry out unstructured mesh generation, and a generated tetrahedral mesh is exported as a. Msh format file; calculating and setting boundary condition parameters of fracture-cavity displacement; setting initial pressure distribution, initial fluid distribution and initial speed distribution of the model; and importing the. Msh format file into FLUENT software, inputting boundary condition parameters and initial conditions, and solving the fracture-cavity model. According to the scheme, on the basis of high-precision simulation of flow of the 3D printing fracture-cavity physical model, the precision of displacement flow simulation of the fracture-cavity model is improved.

Description

Technical Field

[0001] The present invention relates to the field of fracture-cavity simulation, and in particular to a simulation method, a storage medium and a device based on a 3D printed fracture-cavity model. Background Art

[0002] In order to clarify the law of fluid flow in fractured-vuggy carbonate reservoirs, people usually use physical simulation methods to conduct research. In recent years, 3D printing technology has developed rapidly. Compared with traditional physical model preparation methods such as plexiglass, 3D printed physical models can print the pore distribution of the real fracture-cavity space according to the size and shape characteristics of real fractures and cavities through computer control, with high fracture-cavity characterization accuracy and a shape very close to the actual situation. The high-precision fracture-cavity model provides a model basis for high-precision simulation, but there is currently a lack of a high-precision simulation method based on 3D printed models.

[0003] Currently, there are two types of methods to simulate large-scale fracture-cavity models.

[0004] The first type is the equivalent medium model, that is, an equivalent continuous medium model is used to simulate the coupling effect of fractures, cavities and matrix, which is the so-called dual / multiple medium model. The most widely used equivalent medium model is the multiple medium model. The basic principle of this model is to use a structured grid as the equivalent representation unit body, separate the fractures and the rock matrix for processing. A grid may simultaneously contain the three medium properties of matrix-fracture-cavity, and the mass exchange of fluid between the two is characterized by the crossflow equation. The equivalent medium model method is intuitive, simple to model, and fast in simulation, and has been well applied in dealing with strongly connected fractured-vuggy reservoir systems and large-scale model flows. However, this model cannot consider the real shape of fractures and cavities, and has low accuracy; in addition, some of the assumptions used in the model are quite different from the actual situation, such as ignoring the consideration of the actual fracture-cavity connection relationship; another example is that the multiple medium model usually uses the calculation method of "instantaneous gravity differentiation and instantaneous pressure balance" for the fluid in the cavity. For reservoir-scale models, this approximation is acceptable, but for physical model-scale models, it will lead to large errors.

[0005] The second type of method is called the discrete medium model. Different from the equivalent medium, the discrete fracture-vug model describes all fractures completely and explicitly according to their actual sizes and distribution patterns. In the discrete fracture-vug model, one grid corresponds to only one type of medium (matrix, fracture or vug). The fracture-vug reservoir system is presented through a high-resolution unstructured grid, enabling the original characterization of the fracture-vug model. The concept of the discrete fracture-vug model was only proposed in the late 1990s. This method uses the finite volume method and describes the transmissibility between arbitrarily connected grids in the form of a connectivity table. Compared with the equivalent medium model, the discrete fracture-vug model describes fractures more precisely. However, the current method still uses the Darcy-type flow equation for the flow in vugs. This treatment method has an acceptable simulation error for real reservoirs, but for scaled-down physical models, this treatment method may lead to larger errors. In addition, commercial simulation software such as Ansys FLUENT and Comsol usually cannot directly generate meshes on 3D printed models, and lack complete support for 3D printed physical models in the workflow.

[0006] Therefore, there is an urgent need in the industry to develop a method that can perform high-precision simulation on 3D printed fracture-vug physical models to improve the accuracy of the simulation of the displacement flow in the fracture-vug model. Summary of the Invention

[0007] The present invention solves the problem of the lack of a method for high-precision simulation of 3D printed fracture-vug physical models, and provides a simulation method, a storage medium and a device based on a 3D printed fracture-vug model to solve this technical problem. By establishing a numerical model corresponding to the 3D printed fracture-vug physical model, high-precision simulation of the flow based on the 3D printed fracture-vug physical model is realized, and the accuracy of the simulation of the displacement flow in the fracture-vug model is improved.

[0008] To solve the above technical problems, the technical solution of the present invention is as follows:

[0009] A simulation method based on a 3D printed fracture-vug model, comprising the following steps:

[0010] S1. Generate an overall boundary geometry based on the 3D printed fracture-vug model data volume in STL format and store it as a file in poly data format. The data items of the poly data format file include node data, face data, hole data and partition data;

[0011] S2. Describe the boundary geometry using the piecewise linear structure method, then perform unstructured grid meshing on the boundary geometry using the TetGen algorithm, and export the generated tetrahedral mesh as a.msh format file;

[0012] S3. On the generated unstructured grid, calculate and set the boundary condition parameters for fracture-cavity displacement, where the Neumann boundary condition is adopted at the inlet, and the Dirichlet boundary condition is adopted at the outlet;

[0013] S4. On the basis of the boundary condition limitation, set the initial conditions of the model, and the initial conditions include the initial pressure distribution, the initial fluid distribution and the initial velocity distribution of the model;

[0014] S5. Import the.msh format file generated by the fracture-cavity model into the FLUENT software, input the boundary condition parameters and the initial conditions, and solve the fracture-cavity model.

[0015] Preferably, when storing the boundary geometry as a file in poly data format in step S1, the node data, face data, hole data and partition data are specifically:

[0016] The node data includes the number, geometric dimension, number of node attributes and whether the node has a mark of each node;

[0017] The face data includes the number of each face and whether the face has a mark. According to the number of faces, the face data is divided into multiple data blocks, and each data block includes all node indexes of all polygons on the corresponding face;

[0018] The hole data includes the number of each geometric hole and the midpoint coordinates of each geometric hole;

[0019] The partition data includes the number of each partition and the corresponding attributes of the partition.

[0020] Preferably, when there is a hole on the face, the corresponding data block of the face further includes the number and coordinates (x, y, z) of the hole, and the hole is represented by the polygon where the point (x, y, z) is located.

[0021] Preferably, the partition data includes the pipe flow and seepage partitions obtained by calculating the flow Reynolds number. Different partitions correspond to different labels, and the porosity and viscous resistance of different partitions are different.

[0022] Preferably, when calculating the boundary condition parameters of fracture-cavity displacement in step S3:

[0023] The Neumann boundary condition is adopted at the inlet. Assuming that the injection rate of the inlet Ω inlet is q inlet (volume rate, unit: m 3 / s), it is necessary to convert it into the linear velocity v inlet (linear rate, unit: m / s):

[0024]

[0025] A inlet is the area of the inlet boundary;

[0026] For the outlet with Dirichlet boundary conditions, the absolute pressure at the outlet needs to be converted to the relative pressure P outlet (gauge pressure) using the formula:

[0027]

[0028] P sc is the local ambient pressure.

[0029] Preferably, when setting the initial conditions of the model in step S4:

[0030] For the initial pressure distribution setting, use the initial relative pressure P outlet consistent with the relative pressure P init for characterization:

[0031]

[0032] wherein, is the initial absolute pressure at the outlet;

[0033] For the initial fluid distribution setting, use model zoning or directly set fluid zoning according to the model coordinates;

[0034] For the initial velocity distribution setting, the initial flow field of the fracture-vug model is stationary, and the velocity field v(x, y, z) = 0.

[0035] Preferably, the steps of using the FLUENT simulation solver in step S5 are:

[0036] S5-1. Import the generated mesh.msh file into the FLUENT program;

[0037] S5-2. Select a 2D or 3D solver according to the established model, check the imported mesh (Grid→Check), and if there are negative volumes in the mesh, re-mesh;

[0038] S5-3. Select the solver format and solver type (Define→Models→Solver);

[0039] S5-4. Determine the physical properties of the material (Define→Materials);

[0040] S5-5. Set the operating environment (Define→Operating Conditions);

[0041] S5-6. Define boundary conditions;

[0042] S5-7. Calculate control parameters (Solve→Controls→Solution);

[0043] S5-8. Initialize the flow field (Solve→Initialize);

[0044] S5-9. Start the calculation (Solve→Iterate).

[0045] Preferably, after solving the fracture-vug model in step S5, the obtained solution results are exported and stored, and then image processing and analysis are performed on the obtained solution results.

[0046] A computer-readable storage medium stores computer-executable instructions therein, and when the computer-executable instructions are executed by a processor, they are used to implement the above-mentioned simulation method based on a 3D printed fracture-vug model.

[0047] A computer device includes a processor and a memory. The memory stores a computer program, and the computer program is loaded and executed by the processor to implement the above-mentioned simulation method based on a 3D printed fracture-vug model.

[0048] Advantageous technical effects of the technical solution of the present invention:

[0049] (1) In this solution, based on a 3D printed high-precision fracture-vug physical model, boundary geometries and unstructured grids are generated, model boundary conditions and initial conditions are set, and then the FLUENT software is used to solve the flow process based on the Navier-Stokes equation, so as to achieve high-precision flow simulation based on a high-precision 3D printed fracture-vug physical model.

[0050] Moreover, in this solution, the boundary geometry is described by the piecewise linear structure method. The piecewise linear structure is a set composed of points, lines, and surfaces describing the geometric shape of the model, and the same description method is used for the description of each surface, which can flexibly and simply handle geometric bodies mixed with points, lines, surfaces, and volumes.

[0051] Then, the boundary geometry is meshed into unstructured grids by the TetGen algorithm. TetGen has the characteristics of high operating efficiency and high grid quality, and has good applicability to general three-dimensional problems. It can easily handle the situation of mixing points, lines, surfaces, and volumes. When applied to the geometric model of fractured reservoir modeling, it can improve the quality of the generated grids, and can also achieve different parameter controls through commands, which helps the subsequent FLUENT solver to perform high-precision simulation. Description of the Drawings

[0052] Figure 1 Shows the flowchart of solving the 3D printed fracture-vug model using the FLUENT solver in an embodiment of the present invention;

[0053] Figure 2 Shows the structural schematic diagram of the overall boundary geometry corresponding to the poly data format in an embodiment of the present invention;

[0054] Figure 3 Shows the structural schematic diagram of the 3D printed fracture-vug physical model in an embodiment of the present invention;

[0055] Figure 4 Shows the structural schematic diagram of the boundary geometry of the model in an embodiment of the present invention;

[0056] Figure 5 Shows the structural schematic diagram of the unstructured mesh of the model in an embodiment of the present invention;

[0057] Figure 6 Shows the structural schematic diagram of the water flooding boundary condition of the model in an embodiment of the present invention;

[0058] Figure 7 Shows the structural schematic diagram of the initial condition (filled with oil) of the model in an embodiment of the present invention;

[0059] Figure 8 Shows the structural schematic diagram of the water flooding simulation result of the model in an embodiment of the present invention;

[0060] Figure 9 Shows the structural schematic diagram of the numerical simulation result based on the Darcy equation in the prior art. Detailed implementation manners

[0061] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the simulation method, storage medium and device based on the 3D printed fracture-vug model proposed by the present invention will be further described in detail below with reference to the accompanying drawings and specific implementation manners. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are in a very simplified form and all use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the purpose of the implementation manners of the present invention. In order to make the objectives, features and advantages of the present invention more obvious and understandable, please refer to the accompanying drawings. It should be noted that the structures, scales, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions of the implementation of the present invention. Therefore, they do not have technical essence. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the objectives that can be achieved, should still fall within the scope covered by the technical content disclosed by the present invention.

[0062] The following will combine the attached Figures 1 to 9 drawings and specific embodiments to elaborate in detail the technical solutions of a simulation method, storage medium and device based on a 3D printed fracture-vug model of the present invention.

[0063] Embodiment

[0064] As Figures 1 to 9 shown, the simulation method based on the 3D printed fracture-vug model of this embodiment includes the following steps:

[0065] S1. Generate an overall boundary geometry based on the 3D printed fracture-vug model data volume in STL format, and store it as a file in poly data format. The data items of the poly data format file include node data, face data, hole data, and partition data.

[0066] S2. Use the piecewise linear structure method to describe the boundary geometry, then perform unstructured grid meshing on the boundary geometry with the TetGen algorithm, and export the generated tetrahedral mesh as a.msh format file.

[0067] S3. On the generated unstructured grid, calculate and set the boundary condition parameters for fracture-vug displacement, where the inlet uses the Neumann boundary condition and the outlet uses the Dirichlet boundary condition.

[0068] S4. On the basis of the boundary condition limitation, set the initial conditions of the model, and the initial conditions include the initial pressure distribution of the model, the initial fluid distribution of the model, and the initial velocity distribution of the model.

[0069] S5. Import the.msh format file generated by the fracture-vug model into the FLUENT software, input the boundary condition parameters and initial conditions, and solve the fracture-vug model.

[0070] When generating the boundary geometry using the 3D printed fracture-vug model in step S1, it is necessary to generate the overall boundary geometry based on the 3D printed fracture-vug model data volume (STL format) and store it in a specific polyhedron (poly) format to meet the requirements of subsequent unstructured grid generation. The poly data format is divided into 4 parts: node data, face data, hole data, and partition data. None of the four parts can be missing (null values are allowed). The following will elaborate on these 4 parts respectively, where the items in angle brackets <> represent non-missing data, the items in square brackets [] represent data that can be missing depending on the specific data in front, and the items in curly braces {} represent the number of rows.

[0071] 1 - Node data, which has 1 + NPoint lines of data, where NPoint is the number of nodes. The node data includes the number, geometric dimension, number of node attributes, and whether the node has a mark of each node. Whether it has a mark can be represented by 0 and 1 for yes and no respectively.

[0072]

[0073] 2 - Face data, which includes the number of each face and whether the face has a mark. According to the number of faces, the face data is divided into multiple data blocks, and each data block includes all node indices of all polygons on the corresponding face.

[0074]

[0075] It is later divided into NFacet data blocks. In each data block, there are

[0076] 1 + NFacetPolygon + NFacetHole lines of data. NFacetPolygon represents the number of polygons, and NFacetHole represents the number of holes on the face. The first line of each small block has 3 data, and the last two data can be defaulted, with the default value being 0.

[0077] If there are holes on the face, the holes on the face need to be numbered in sequence and described by the coordinates of a point. For example, describing the hole on the face by the point (x, y, z) means using the polygon where the point (x, y, z) is located to represent the corresponding hole.

[0078]

[0079] 3 - Hole data, which includes the number of each geometric hole and the midpoint coordinates of each geometric hole. This part has 1 + NHole lines of data, where NHole is the number of geometric holes.

[0080] The description method of geometric holes is similar to that of holes on the face. The hole (x, y, z) in the hole data means that the inside of the closed surface where the point (x, y, z) is located in the region is a hole.

[0081] {1} <nhole> < / nhole> {2 to 1 + NHole} <Hole number i>+ <x> + <y> + <z> < / z> < / y> < / x>

[0082] 4 - Partition data, which is used to represent partitions such as pipe flow and seepage flow obtained by calculating the flow Reynolds number. Different partitions have different labels. The partition attributes refer to parameters such as porosity and viscous resistance. The porosity and viscous resistance parameters in different partitions are quite different, so partitioning is needed for distinction.

[0083] This part has 1 + NRegion lines of data, where NRegion is the number of partitions.

[0084]

[0085] Example of data file (# indicates comments):

[0086]

[0087] The above data file represents the geometric body attached Figure 2 in it.

[0088] In step S2, in order to generate unstructured meshes, first, the boundary geometric body generated above needs to be described by the Piecewise Linear Complex (PLC) method. The piecewise linear structure is a set composed of points, lines, and faces describing the geometric shape of the model. The description of each face uses the same description method, that is: each of its faces is a polygon, which may have multiple sides and may be a non-convex polygon, and may also contain void areas, separate edges, or discrete isolated points. The advantage of such a description method is that it is very flexible and can easily handle geometric bodies mixed with points, lines, surfaces, and solids.

[0089] Next, the TetGen algorithm is used to perform unstructured mesh dissection on the above boundary geometric body. As a Constraint Delaunay three-dimensional mesh generation algorithm, TetGen has the advantages of high operating efficiency and high mesh quality, and has good applicability to general three-dimensional problems. It can easily handle the situation of mixing points, lines, surfaces, and solids, which is the geometric model used in our fractured reservoir modeling; the generated mesh quality is relatively high, and different parameter controls can also be achieved through commands.

[0090] There are many control parameters and commands in the mesh dissection process using the TetGen algorithm, which can be controlled and adjusted according to needs. However, specifically applied to the 3D printed fracture-vug physical model, the following several commands are mainly used:

[0091]

[0092] The generated tetrahedral mesh is exported in the *.msh format.

[0093] Specifically, in step S3, when generating unstructured meshes, it is necessary to calculate and set the boundary condition parameters for fracture-vug displacement. Among them:

[0094] The inlet adopts the Neumann boundary condition. Assuming that the injection rate of the inlet Ω inlet is q inlet (volume rate, unit: m3 / s), it is necessary to convert it into the linear velocity v inlet (linear rate, unit: m / s):

[0095]

[0096] A inlet is the area of the inlet boundary;

[0097] For the outlet with Dirichlet boundary conditions, the absolute pressure at the outlet needs to be converted to the relative pressure P outlet (gauge pressure) using the formula:

[0098]

[0099] P sc is the local ambient pressure.

[0100] Specifically, when setting the initial conditions of the model in step S4:

[0101] For the initial pressure distribution setting, use the initial relative pressure P outlet consistent with the relative pressure P init for characterization:

[0102]

[0103] where is the initial absolute pressure at the outlet.

[0104] For the initial fluid distribution setting, use zonal data or directly set the fluid zones according to the model coordinates. For example, when dividing the model into different fluid distribution regions such as oil, gas, and water according to the model coordinates, the oil zone and the water zone can be divided according to the Z coordinate in the fracture-vug structure.

[0105] For the initial velocity distribution setting, the initial flow field of the fracture-vug model is stationary, and the velocity field v(x, y, z) = 0.

[0106] Specifically, the steps for using the FLUENT simulation solver in step S5 are as follows:

[0107] S5-1. Import the generated mesh.msh file into the FLUENT program;

[0108] S5-2. Select the 2D or 3D solver according to the established model, check the imported mesh (Grid→Check). If there are negative volumes in the mesh, re-mesh;

[0109] S5-3. Select the solver format and solver type (Define→Models→Solver);

[0110] S5-4. Determine the physical properties of the material (Define→Materials);

[0111] S5-5. Set the operating environment (Define→Operating Conditions);

[0112] S5-6. Define the boundary conditions (Define→boundary conditions);

[0113] S5-7. Calculate the control parameters (Solve→Controls→Solution);

[0114] S5-8. Initialize the flow field (Solve→Initialize);

[0115] S5-9. Start the calculation (Solve→Iterate).

[0116] In this solution, based on the 3D printed high-precision fracture-vug physical model, the boundary geometry and unstructured mesh are generated, the model boundary conditions and initial conditions are set, and then the FLUENT software is used to solve the flow process based on the Navier-Stokes equation, realizing high-precision flow simulation based on the high-precision 3D printed fracture-vug physical model.

[0117] The Navier-Stokes equation is the equation of motion that describes the momentum conservation of viscous incompressible fluids. It is abbreviated as the N-S equation. The N-S equation reflects the basic mechanical laws of the flow of viscous fluids (also known as real fluids) and has very important significance in fluid mechanics. Theoretically, with the basic equations including the N-S equation, plus certain initial conditions and boundary conditions, the flow of fluids can be determined.

[0118] Moreover, the TetGen algorithm is used to perform unstructured mesh division on the above boundary geometry. As a ConstraintDelaunay three-dimensional mesh generation algorithm, TetGen has the characteristics of high operating efficiency and high mesh quality, has good applicability to general three-dimensional problems, can easily handle the mixed situation of points, lines, surfaces and solids, and is the geometric model used in fracture reservoir modeling; the generated mesh has relatively high quality, and different parameter controls can also be achieved through commands, which helps the subsequent FLUENT solver to perform high-precision simulation.

[0119] Comparing with the numerical simulation results based on the traditional Darcy equation, it can be found that due to the neglect of the inertial term in the traditional method, the pure viscous flow leads to a gradual transition of the water saturation, which does not conform to the real situation. The simulation results of the method of the present invention have higher accuracy, and the oil-water interface is depicted more precisely.

[0120] In addition, there are many methods for generating meshes. Figure 1In the flowchart, ICEM CFD is taken as an example, but it should be understood that the method of generating the mesh can be replaced by other methods.

[0121] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0122] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A simulation method based on a 3D printed fracture-vug model, characterized in that It includes the following steps: S1. Generate an overall boundary geometry based on the STL-format 3D printed fracture-vug model data volume and store it as a file in poly data format. The data items of the poly data format file include node data, face data, hole data, and partition data; S2. Describe the boundary geometry using the piecewise linear structure method, then perform unstructured grid meshing on the boundary geometry with the TetGen algorithm, and export the generated tetrahedral mesh as a.msh format file; S3. On the generated unstructured grid, calculate and set the boundary condition parameters for fracture-vug displacement. Among them, the Neumann boundary condition is adopted at the inlet, while the Dirichlet boundary condition is adopted at the outlet; S4. On the basis of the boundary condition limitation, set the initial conditions of the model. The initial conditions include the initial pressure distribution of the model, the initial fluid distribution of the model, and the initial velocity distribution of the model; S5. Import the.msh format file generated by the fracture-vug model into the FLUENT software, input the boundary condition parameters and initial conditions, and solve the fracture-vug model.

2. The simulation method based on a 3D printed fracture-vug model according to claim 1, characterized in that, When storing the boundary geometry as a file in poly data format in step S1, the node data, face data, hole data, and partition data are specifically as follows: The node data includes the number, geometric dimension, number of node attributes, and whether the node has a mark of each node; The face data includes the number of each face and whether the face has a mark. According to the number of faces, the face data is divided into multiple data blocks, and each data block includes all node indices of all polygons on the corresponding face; The hole data includes the number of each geometric body hole and the midpoint coordinates of each geometric body hole; The partition data includes the number of each partition and the corresponding attributes of the partition.

3. The simulation method based on a 3D printed fracture-vug model according to claim 2, characterized in that When there is a hole on the face, the corresponding data block of the face also includes the number of the hole and the coordinates (x, y, z), and the hole is represented by the polygon where the point (x, y, z) is located.

4. The simulation method based on a 3D printed fracture-vug model as claimed in claim 1, wherein, The partition data includes pipe flow and seepage partitions obtained by calculating the flow Reynolds number. Different partitions correspond to different labels, and the porosity and viscous resistance of different partitions are different.

5. The simulation method based on a 3D printed fracture-vug model according to claim 1, characterized in that, When calculating the boundary condition parameters for fracture-vug displacement in step S3: The inlet adopts Neumann boundary conditions, assuming the inlet is Ω inlet with an injection rate of q inlet (volume rate, in units of m 3 / s), which needs to be converted to the linear velocity v inlet (linear rate, in units of m / s): A inlet is the area of the inlet boundary; The outlet adopts the Dirichlet boundary condition, and it is necessary to convert the absolute pressure at the outlet into the relative pressure P outlet (gauge pressure), and the formula is: P sc is the local ambient pressure.

6. The simulation method based on a 3D printed fracture-vug model according to claim 5, wherein, When setting the initial situation of the model in step S4: Initial pressure distribution setting, using the initial relative pressure P outlet consistent with the relative pressure P init for characterization: Among them, is the initial absolute pressure at the outlet; For the initial fluid distribution setting, the fluid partition is set by model partitioning or directly according to the model coordinates; For the initial velocity distribution setting, the initial flow field of the fracture-vug model is stationary, and the velocity field v(x, y, z) = 0.

7. The simulation method based on a 3D printed fracture-vug model according to claim 1, wherein The steps of using the FLUENT simulation solver in step S5 are: S5-1. Import the generated mesh.msh file into the FLUENT program; S5-2. Select the 2D or 3D solver according to the established model, check the imported mesh (Grid→Check). If there is a negative volume in the mesh, re-mesh; S5-3. Select the solver format and solver type (Define→Models→Solver); S5-4. Determine the physical properties of the material (Define→Materials); S5-5. Set the operating environment (Define→Operating Conditions); S5-6. Define the boundary conditions (Define→boundary conditions); S5-7. Calculate the control parameters (Solve→Controls→Solution); S5-8. Initialize the flow field (Solve→Initialize); S5-9. Start the calculation (Solve→Iterate).

8. The simulation method based on a 3D printed fracture-vug model according to claim 1, characterized in that After solving the fracture-vug model in step S5, export and store the solution results, and then perform image processing and analysis on the solution results.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the simulation method based on the 3D printed fracture-vug model according to any one of claims 1 to 8.

10. A computer device, characterized in that, The computer device includes a processor and a memory, the memory stores a computer program, and the computer program is loaded and executed by the processor to implement the simulation method based on the 3D printed fracture-vug model according to any one of claims 1 to 8.

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