CN112507551B

CN112507551B - Unstructured dynamic mesh generation method and device

Info

Publication number: CN112507551B
Application number: CN202011426850.XA
Authority: CN
Inventors: 李熙喆; 雷征东; 杨正明; 徐建春; 姚尚林
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-12-09
Filing date: 2020-12-09
Publication date: 2022-11-04
Anticipated expiration: 2040-12-09
Also published as: CN112507551A

Abstract

The application provides an unstructured dynamic mesh generation method and device, which comprise the following steps: generating a dynamic mesh generation result according to the dynamic mesh generation parameters; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometric information and quality control parameters; generating an oil reservoir pressure value according to the dynamic grid subdivision result; updating discrete fractures according to the reservoir pressure value; and updating the dynamic mesh generation result based on the updated discrete fracture. According to the dynamic mesh generation method and device, the dynamic mesh generation result can be updated according to the dynamic mesh generation parameters, and dynamic and efficient mesh generation is achieved.

Description

Unstructured dynamic mesh generation method and device

Technical Field

The application relates to the field of oilfield development, in particular to an unstructured dynamic mesh generation method and device.

Background

With the development of low permeability oil fields and ultra-low permeability oil fields, most of the low permeability oil fields and the ultra-low permeability oil fields enter the stage of medium and high water content in China. At this stage, the main spear in oilfield development is that oil well water breakthrough has a significant directionality, which is expressed as: the water content of the water injection well is increased in a step mode in the direction of the maximum horizontal main stress of a stress field (a main well for short), a corresponding well testing interpretation curve of the water injection well shows the fracture seepage characteristic, a water absorption profile shows that the peak-shaped water absorption of individual intervals is realized, and the tracer agent monitoring has obvious directionality. These problems are mainly caused by the initiation and propagation of low permeability reservoir dynamic fractures. Because the oil reservoir is a favorable factor for increasing the flow conductivity and a unfavorable factor for causing water channeling under the condition of long-term water injection, the oil reservoir needs to be depicted and numerically simulated in the field of oil field development so as to more clearly master the underground condition of the oil reservoir. However, there are still significant challenges to the characterization and numerical simulation of such reservoirs.

In order to solve the above problems, the prior art generally adopts the following two methods: the dual medium model method and the discrete fracture model method are both effective means for realizing numerical simulation of fractured reservoirs. The two models have different characteristics and adaptability respectively: the dual medium model has the advantages of stability and high efficiency, but has lower precision, is usually only suitable for the region where medium and small cracks develop and is not suitable for the condition that the oil reservoir has large-scale cracks; the discrete fracture model is characterized by fine fracture carving and high numerical simulation precision, as shown in fig. 1, the leftmost image is a fracture oil reservoir schematic diagram, a plurality of fractures develop in an oil reservoir area, the middle image is a simulation result by using a dual medium model, and the rightmost image is a simulation result by using the discrete fracture model.

Based on the above, currently, a discrete fracture model is generally adopted for performing numerical simulation on a low-permeability fractured reservoir so as to realize high-precision depiction of a fracture system. Discrete fracture models typically explicitly characterize the fracture using a more flexible unstructured grid, namely: the grid used for numerical simulation fully conformed to the geometry of the fracture. However, for dynamic fractures that are dynamically initiated and expanded along with water injection during the development process, the conventional static unstructured grid partitioning method cannot adapt to the real-time change characteristics of the fractures. As shown in fig. 2, the numerical simulation unstructured grid used at the previous time completely fits the geometry of the discrete fracture network at the previous time (black bold line in the left diagram of fig. 2), however, as the water drive development advances, the dynamic fracture continues to expand (shown in the right diagram of fig. 2), which is embodied as the fracture length increases, at this time, the old grid cannot fit the geometry of the new fracture network, and the new fracture system must be re-split at this time.

Currently, the research results on dynamic discrete fracture models at home and abroad are few, and the main reason is the late attention on dynamic fractures. Because the research is started late, a dynamic unstructured mesh generation technology for numerical simulation of dynamic discrete fractures of low-permeability reservoirs is still lacking at present. The traditional static unstructured grid generation technology cannot be used, the static unstructured grid technology assumes that the crack information is known, and during simulation, relevant attribute parameters of a crack grid or a near crack grid are updated only according to opening, closing and expansion of cracks without re-generation of grids. As shown in fig. 3, the research area has one injection well (INJE) and one production well (PROD), and during simulation, the propagation direction of the fracture is preset, and then simulation is performed.

Based on the above, the static unstructured grid subdivision technology needs to assume that the crack propagation direction is known when simulating a dynamic crack, so that simulation errors are caused. Therefore, the static unstructured grid-splitting technology cannot be used for an actual model with uncertain fracture crack initiation positions and propagation directions.

Disclosure of Invention

Aiming at the problems in the prior art, the application provides an unstructured dynamic mesh generation method and an unstructured dynamic mesh generation device, which can update a dynamic mesh generation result according to dynamic mesh generation parameters and realize dynamic and efficient mesh generation.

In order to solve the technical problem, the application provides the following technical scheme:

in a first aspect, the present application provides an unstructured dynamic mesh generation method, including:

generating a dynamic mesh generation result according to the dynamic mesh generation parameters; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometrical information and quality control parameters;

generating an oil reservoir pressure value according to the dynamic grid subdivision result;

updating the discrete fractures according to the oil reservoir pressure value;

and updating the dynamic mesh generation result based on the updated discrete fracture.

Further, the generating a dynamic mesh generation result according to the dynamic mesh generation parameter includes:

generating POLY data according to the boundary information of the three-dimensional geological model and the geometrical information of the discrete fracture grid; the POLY data includes: boundary crack node data, boundary crack face data, boundary crack hole data and boundary crack partition data;

calling the POLY data to generate a dynamic mesh generation result according to the quality control parameters; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data.

Further, the generating a reservoir pressure value according to the dynamic mesh generation result includes:

calculating the conductivity of adjacent discrete fracture grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model;

and predicting a reservoir pressure value according to the conductivity of the adjacent discrete fracture grids.

Further, before generating a reservoir pressure value according to the dynamic mesh generation result, the method comprises the following steps:

calculating the volume of each discrete crack grid according to the node coordinates of each discrete crack grid in the three-dimensional geological model;

acquiring the porosity of each discrete crack grid in the three-dimensional geological model and the central point of each discrete crack grid;

and obtaining the depth value of each discrete crack grid according to the central point of each discrete crack grid.

Further, the calculating the conductivity of the adjacent discrete fracture grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model includes:

calculating the conductivity between the matrix and the cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result, the length from the grid center point to the grid connection surface center point, the unit normal vector of the grid connection surface pointing to the grid and the unit direction vector of the grid connection surface center point pointing to the grid center point;

and calculating the conductivity between the adjacent cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result and the distance between the grid central points.

Further, the pressure values include pore pressure values, and updating the discrete fractures according to the reservoir pressure values includes:

calculating a rock fracture pressure threshold according to the pore pressure numerical value and overburden pressure, poisson's ratio, a geological structure stress coefficient and tensile strength in the three-dimensional geological model;

calculating a fracture extension pressure threshold according to the minimum horizontal principal stress, the fracture surface energy, the elastic modulus and the fracture half-length in the three-dimensional geological model;

and updating the discrete fractures according to the current fracture form, the rock fracture pressure threshold, the fracture extension pressure threshold, the space stress field of the region corresponding to the three-dimensional geological model and the pore pressure field.

Further, after updating the dynamic mesh generation result based on the updated discrete fracture, the method further comprises:

and carrying out grid attribute migration according to the updated dynamic grid subdivision result.

In a second aspect, the present application provides an unstructured dynamic mesh generation apparatus, including:

the subdivision result generation unit is used for generating a dynamic mesh subdivision result according to the dynamic mesh subdivision parameters; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometrical information and quality control parameters;

the pressure value generating unit is used for generating an oil reservoir pressure value according to the dynamic grid subdivision result;

the discrete fracture updating unit is used for updating discrete fractures according to the oil reservoir pressure value;

and the subdivision result updating unit is used for updating the dynamic mesh subdivision result based on the updated discrete fracture.

Further, the subdivision result generation unit includes:

the POLY data generation module is used for generating POLY data according to the three-dimensional geological model boundary information and the discrete fracture grid geometric information; the POLY data includes: boundary crack node data, boundary crack face data, boundary crack hole data and boundary crack partition data;

the subdivision result generation module is used for calling the POLY data to generate a dynamic mesh subdivision result according to the quality control parameter; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data.

Further, the pressure value generation unit includes:

the conductivity calculation module is used for calculating the conductivity of adjacent discrete fracture grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model;

and the pressure value generation module is used for predicting the reservoir pressure value according to the conductivity of the adjacent discrete fracture grids.

Further, the unstructured dynamic mesh generation device further comprises:

the volume calculation unit is used for calculating the volume of each discrete crack grid according to the node coordinates of each discrete crack grid in the three-dimensional geological model;

the porosity central point acquisition unit is used for acquiring the porosity of each discrete fracture grid in the three-dimensional geological model and the central point of each discrete fracture grid;

and the depth value generating unit is used for obtaining the depth value of each discrete fracture grid according to the central point of each discrete fracture grid.

Further, the conductivity calculation module includes:

the conductivity between the base seams is calculated by a conductivity calculation module, and the conductivity between the matrix and the cracks is calculated according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result, the length from the grid center point to the grid connection surface center point, the unit normal vector of the grid connection surface pointing to the grid and the unit direction vector of the grid connection surface center point pointing to the grid center point;

and the conductivity calculation module of the adjacent cracks is used for calculating the conductivity between the adjacent cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result and the distance between the grid central points.

Further, the pressure value comprises a pore pressure value, and the discrete fracture updating unit comprises:

the fracture pressure threshold determination module is used for calculating a rock fracture pressure threshold according to the pore pressure value, overburden pressure, poisson's ratio, geological structure stress coefficient and tensile strength in the three-dimensional geological model;

the extension pressure threshold value determining module is used for calculating a fracture extension pressure threshold value according to the minimum horizontal principal stress, the fracture surface energy, the elastic modulus and the fracture half-length in the three-dimensional geological model;

and the discrete fracture updating module is used for updating the discrete fractures according to the current fracture form, the rock fracture pressure threshold, the fracture extension pressure threshold, and the space stress field and the pore pressure field of the region corresponding to the three-dimensional geological model.

Further, the discrete fracture updating unit is further specifically configured to:

and carrying out grid attribute migration according to the updated dynamic grid generation result.

In a third aspect, the present application provides an electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the unstructured dynamic mesh generation method when executing the program.

In a fourth aspect, the present application provides a computer readable storage medium, on which a computer program is stored, which computer program, when being executed by a processor, performs the steps of the unstructured dynamic mesh generation method.

Aiming at the problems in the prior art, the application provides an unstructured dynamic mesh generation method, which can update a dynamic mesh generation result according to dynamic mesh generation parameters, so that a mesh model can be dynamically updated according to crack initiation, crack expansion and crack closure and is matched with an actual crack network in real time, a high-precision discrete crack model is applied to an oil field with dynamic crack expansion, the fine simulation of a crack dynamic change process in a low-permeability long-term water injection process is realized, and a powerful tool is provided for the precise prediction, fine management and scheme optimization of low-permeability reservoir development.

Drawings

FIG. 1 is a schematic diagram of a fracture oil reservoir and its corresponding dual medium model result and a schematic diagram of a discrete fracture model result in an embodiment of the present application;

FIG. 2 is a schematic diagram of a last-time numerically-simulated unstructured grid and a discrete fracture updated at a current time in an embodiment of the present application;

FIG. 3 is a schematic diagram of a static unstructured grid simulating dynamic fracture propagation in an embodiment of the present application;

fig. 4 is a flowchart of an unstructured dynamic mesh generation method in an embodiment of the present application;

FIG. 5 is a flowchart of generating a dynamic mesh generation result in an embodiment of the present application;

FIG. 6 is a flow chart of generating reservoir pressure values in an embodiment of the present application;

FIG. 7 is a second flowchart of an unstructured dynamic meshing method according to an embodiment of the present application;

FIG. 8 is a flow chart of the calculation of conductivity for adjacent discrete fracture grids in an embodiment of the present application;

FIG. 9 is a flow chart for updating discrete fractures in an embodiment of the present application;

fig. 10 is one of the structural diagrams of the unstructured dynamic meshing device in the embodiment of the present application;

fig. 11 is a structural diagram of a subdivision result generation unit in the embodiment of the present application;

FIG. 12 is a structural diagram of a pressure value generation unit in the embodiment of the present application;

FIG. 13 is a second block diagram of an unstructured dynamic meshing device in an embodiment of the present application;

fig. 14 is a block diagram of a conductivity calculation module in an embodiment of the present application;

FIG. 15 is a block diagram of a discrete fracture update unit in an embodiment of the present application;

fig. 16 is a schematic structural diagram of an electronic device in an embodiment of the present application;

FIG. 17 is a schematic of fractures in a reservoir in an embodiment of the present application.

FIG. 18 is a schematic view of a fracture dimensionality reduction process in mesh generation in an embodiment of the present application;

FIG. 19 is a schematic diagram of a flow calculation method in an embodiment of the present application;

FIG. 20 is a graph showing the calculation of one-dimensional fracture conductivity in the examples of the present application;

FIG. 21 illustrates the difference between the computational model and the fracture grid in the grid model in an embodiment of the present application;

FIG. 22 is a schematic diagram illustrating the geometrical topological distribution of two fractures after propagation at this time step in the present embodiment;

FIG. 23 is a schematic diagram of an embodiment of the present application for repartitioning an unstructured network;

fig. 24 is a schematic diagram illustrating a determination of a region envelope in the embodiment of the present application;

FIG. 25 is a schematic representation of matrix mesh property mapping in an embodiment of the present application;

FIG. 26 is a diagram of an unstructured grid and a corresponding unstructured grid model in an embodiment of the present application;

FIG. 27 is a schematic diagram of an exemplary embodiment of an automated model boundary extraction and unstructured grid model;

FIG. 28 is a graph of simulation process grid dynamics and saturation changes in an embodiment of the present application;

FIG. 29 is a schematic diagram of a W1 well at the time of rapid water rise (day 1100) and corresponding fractures and unstructured grids in an example of the present application;

FIG. 30 is a graph showing the comparison between the simulation and fitting results of W1 in the example of the present application;

FIG. 31 is a schematic diagram of the W2 well at the time of rapid water rise (day 1300) and the corresponding fractures and unstructured grids in the example of the present application;

FIG. 32 is a schematic comparison of simulation and fitting results for a W2 well in an embodiment of the present application;

FIG. 33 is a schematic diagram of a W3 well at the time of rapid water rise (day 1800) and corresponding fractures and unstructured grids in an example of the present application;

FIG. 34 is a graph showing the comparison between the simulation and fitting results of the W3 well in the example of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 4, in order to update the dynamic mesh generation result according to the dynamic mesh generation parameters and realize dynamic and efficient mesh generation, the application provides an unstructured dynamic mesh generation method, which includes:

s101: generating a dynamic mesh generation result according to the dynamic mesh generation parameters; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometrical information and quality control parameters;

s102: generating an oil reservoir pressure value according to the dynamic grid subdivision result;

s103: updating the discrete fractures according to the oil reservoir pressure value;

s104: and updating the dynamic mesh generation result based on the updated discrete fracture.

It can be understood that, in the embodiment of the present application, mesh generation can be performed according to the dynamic mesh generation parameters, and the obtained generation result is the generation result of the current time step, and can also be understood as an initial mesh generation result. And obtaining an oil reservoir numerical simulation file through calculation according to the initial mesh generation result. This file contains reservoir pressure values. According to the oil reservoir pressure value, the sample state of the discrete fracture at a certain time step in the future can be predicted, and the updating of the discrete fracture is completed. When the discrete crack mode is updated, the geometrical information of the discrete crack grids is changed. And finally, carrying out grid attribute migration based on the updated discrete fracture, and updating the dynamic grid subdivision result. The specific methods involved in the above steps are described in detail below.

From the description, the application provides an unstructured dynamic mesh generation method, which can update a dynamic mesh generation result according to dynamic mesh generation parameters, so that a mesh model can be dynamically updated according to the crack initiation, expansion and closure, and is matched with an actual crack network in real time, and a high-precision discrete crack model is applied to an oil field with dynamic crack expansion, so that the fine simulation of the dynamic change process of cracks in the low-permeability long-term water injection process is realized, and a powerful tool is provided for the precise prediction, fine management and scheme optimization of low-permeability oil reservoir development.

Referring to fig. 5, the generating a dynamic mesh generation result according to the dynamic mesh generation parameter includes:

s201: generating POLY data according to the boundary information of the three-dimensional geological model and the geometrical information of the discrete fracture grid; the POLY data includes: boundary crack node data, boundary crack face data, boundary crack hole data and boundary crack partition data;

it can be understood that, in the embodiment of the present application, the mesh generation may be completed by using TetGen open source software, and in actual engineering, any commercial software or open source software used for unstructured mesh generation may be used to implement unstructured mesh generation. The mesh generation in the step is equivalent to the initialization of the dynamic mesh generation result, and the mesh generation result can be dynamically updated in real time according to the change of the crack.

To initialize the dynamic mesh generation results, first several quality control parameters need to be specified, see table 1 below:

TABLE 1

Generating POLY data according to the three-dimensional geological model boundary information and the discrete fracture grid geometric information, and writing a data file dfm. Generally, a poly data file is divided into four major parts: boundary crack node data, boundary crack surface data, boundary crack hole data and boundary crack partition data, wherein the four parts are all absent, and null values are allowed to exist. These four sections will be described below, respectively, in which angle brackets < > indicate data that is not defaultable, square brackets [ ] indicate data that is visible to the front face volume data as default, and angle brackets { } indicate line numbers.

(1) Boundary fracture node data, see table 2 below: the portion has 1+ NPoint row data, and NPoint is the number of nodes.

TABLE 2

(2) Boundary crack face data, see table 3 below:

TABLE 3

{1}	<Number of planes N _Facet >+<Whether the surface is provided with a mark (0/1)>

The back is divided into NFacet small blocks, and each small block has data of 1+ NFacetPolygon + NFacetHole. NFacePolygon indicates the number of polygons, and NFaceHole indicates the number of holes on a face. Line 1 of each tile has 3 data, the last two of which can be defaulted to 0.

The hole in the surface is described by the coordinates of a point, and the hole (x, y, z) indicates that the polygon in which the point (x, y, z) is located in the surface is a hole, see table 4 below:

TABLE 4

(3) Boundary fracture hole data, see table 5 below: the part has 1 of N _Hole Line data, N _Hole The number of geometric cavities.

The geometry hole is described in a similar manner to the hole in the surface, and the hole (x, y, z) represents a hole inside the closed curved surface where the area midpoint (x, y, z) is located.

TABLE 5

{1}	<N _Hole >
		{2～1+N _FacetPolygon }	<Hole number i>+<x>+<y>+<z>

(4) Boundary fracture zoning data, see table 6 below: the part has 1+N _Region Line data, N _Region Is the number of partitions.

TABLE 6

Data file examples (# representing comments), see table 7 below:

TABLE 7

S202: calling the POLY data to generate a dynamic mesh generation result according to the quality control parameters; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data.

It is to be appreciated that after generating the POLY data, the POLY data can be invoked to generate the dynamic mesh generation results. The quality control parameters are needed in the step, the quality control parameters of the unstructured grid subdivision are numerous, and when the method is specifically applied to the dynamic discrete fracture grid subdivision, the following commands are mainly used, and the following commands are shown in the following table 8:

TABLE 8

The input control command is read in by a main program for unstructured grid subdivision in a parameter document form and is transmitted to a module, and a result data file is subdivided and output. Specifically, the output result data file is divided into the following files:

node, see table 9 below:

TABLE 9

Edge, see table 10 below:

watch 10

Face, see table 11 below:

TABLE 11

Ele, see table 12 below:

TABLE 12

Neighbor data file of grid tetrahedrons, see table 13 below:

watch 13

If the triangular faces of a certain node pair do not have contiguous tetrahedrons (at the model outer surface or internal hole boundaries), the index is-1.

From the above description, the unstructured dynamic mesh generation method provided by the application can generate a dynamic mesh generation result according to the dynamic mesh generation parameters.

Referring to fig. 6, in S102, generating a reservoir pressure value according to the dynamic mesh generation result includes:

s301: calculating the conductivity of adjacent discrete crack grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model;

it will be appreciated that the dynamic mesh generation result generated in the previous step has divided the corresponding region of the three-dimensional geological model into several adjacent discrete fracture meshes, and the fractures in these discrete fracture meshes are treated as a rectangle with thickness, see fig. 17.

Referring to fig. 18, for the discrete fracture mesh model, the embodiment of the present application uses an unstructured mesh for mesh generation. In order to facilitate mesh generation and subsequent calculation, dimension reduction treatment is carried out on the cracks in the mesh generation process, namely the cracks are treated into line segments in a two-dimensional problem, the width of the line segments is not considered at all, and the cracks are treated into planes in a three-dimensional problem, and the thickness of the line segments is not considered at all. Such a treatment does not lose accuracy because the subsequent calculation model corrects for the volume error caused by this treatment, taking into account the width or thickness of the crack. The black line segments in fig. 18 represent the cracks, the black dots represent the grid center points, and the matrix and cracks are used as control bodies to participate in subsequent calculations. The shape of the unstructured grid can be selected at will, and the central point of the control body is taken as the geometric center of the grid. However, the grid selection is performed to ensure orthogonality (e.g., PEBI grid), i.e., the connection line between the center points of adjacent grids is perpendicular to the intersection line of grids.

After the mesh subdivision is finished, the most important problem is to calculate the conductivity between the fracture matrix meshes so as to predict the reservoir pressure value according to the conductivity.

To introduce the concept of conductivity, for a control body of any shape, the flow formula can be written as:

Q ₁₂ ＝T ₁₂ λ(p ₂ -p ₁ )

wherein Q is ₁₂ Is the flow rate from grid block 1 to grid block 2 per unit time;

p is the lattice block pressure;

T ₁₂ geometric features that are conductivity, which are related only to the properties of the mesh and the porous medium;

λ is the fluidity, which is related to the fluid properties.

Referring to fig. 19, the conductivity calculation formula is as follows:

(1) Conductivity T when oil and gas are conducted between a matrix grid containing no fractures and a grid containing fractures ₁₂ Comprises the following steps:

wherein A is _i The area of the junction of grid 1 and grid 2;

k _i the respective permeabilities of the grids;

D _i the length from the center point of the mesh to the center point of the interface;

n _i a unit normal vector pointing to grid i for the interface;

f _i is the unit direction vector of the center point of the contact surface pointing to the center point of the grid i.

(2) When oil and gas are conducted between two connected grids containing cracks, the conductivity T ₁₂ Comprises the following steps:

wherein A is _i The area of the junction between grid i and grid 0, i.e. the width of grid i;

k _i permeability of the fracture network;

D _i the distance between the center point of grid i and the center point of grid 0, and grid 0 is a virtual grid, which can be infinitely small, so D _i Which is also half the length of the fracture grid i.

Conductivity calculations between three or more connected fracture grids can be obtained by star-delta transformation in an analog circuit:

the meaning of each parameter is similar to the two crack formulas, and specifically comprises the following steps:

A _i -grid iThe area of the intersection with the grid 0, namely the width of the crack grid i;

k _i -fracture grid permeability;

D _i distance between the center point of the i grid and the center point of the 0 grid, and D is the distance between the center point of the 0 grid and the center point of the 0 grid because the 0 grid is a virtual grid and can be infinitely small _i Which is also half the length of the fracture grid i.

In addition, a schematic diagram of the one-dimensional fracture conductivity calculation can be seen in fig. 20.

Referring to fig. 21, in the computational model of fig. 21, the fracture width is reconsidered for correction of the volume error caused by the previous processing method. Because the cracks are represented by line segments in the grid, and the widths of the cracks are considered in the calculation model, the total volume of the corresponding region of the three-dimensional geological model is not conserved. When there are many cracks, the error is more obvious and cannot be ignored. The matrix grid volume is calculated by subtracting half of the matrix grid volume adjacent to the fracture grid from the existing matrix grid volume.

With conductivity, the conductivity information-based unstructured grid reservoir numerical simulator, such as LandSim software, can be used in combination with the discrete fracture geometry information to predict fracture changes at future time steps. According to the format requirement of a specific simulator, the conductivity can be written into a numerical reservoir simulation file and used as an input file of the numerical simulator to carry out numerical simulation operation, and the change of the fracture in the future time step is obtained. It should be noted that the input parameters required by the reservoir numerical simulation file in this step include not only conductivity, but also volume of each discrete fracture mesh, center point of each discrete fracture mesh, and depth value of each discrete fracture mesh. The calculation methods of the above three parameters are detailed in S401 to S403.

S302: and predicting a reservoir pressure value according to the conductivity of the adjacent discrete fracture grids.

It can be understood that the model for judging crack initiation and crack propagation has different models such as a tip stress criterion, a Mohr-Coulomb criterion, a stress concentration factor criterion and the like.

The method and the device adopt a tip stress criterion model to judge crack initiation and crack propagation.

The pressure change rule in the crack generation process is as follows: firstly, continuously raising the bottom hole pressure to the rock stratum fracture pressure to generate fractures; the pressure is then slightly reduced, and the crack is continuously grown and extended under the crack extension pressure, so that the scale is enlarged.

The formation fracture pressure is calculated as follows:

wherein p is _f -formation fracture pressure, MPa;

p _p -pore pressure, MPa;

p _o overburden pressure, MPa;

v-Poisson's ratio;

k is the geological structure stress coefficient without dimension;

S _rt tensile strength, MPa.

The fracture propagation pressure is then calculated by the equation that the fracture propagation pressure needs to overcome at least the sum of the minimum level principal stress and the formation tensile strength:

wherein p is _tip -fracture extension pressure, MPa;

σ _Hmin -minimum horizontal principal stress, MPa;

u-surface energy of seam, J/cm ² ；

E-modulus of elasticity, MPa;

r _f the half-length of the crack, cm.

The formula shows that the tip stress criterion model is relatively simple, the tip fracture critical pore pressure can be calculated only according to the rock mechanical parameters and the ground stress distribution parameters, and the calculated pressure is compared with the pressure calculated by the flow model (conventional oil deposit digital-to-analog), so that whether the fracture is cracked and expanded is judged, and the fracture sample state is updated. The initiation and propagation of the fracture proceeds along the direction of maximum principal stress at the tip of the fracture.

Through the two formulas, a rock stratum fracture pressure threshold value and a fracture extension pressure threshold value can be obtained through calculation, and software such as Ansys and COMSOL can be adopted for calculation according to the two threshold values, so that fracture initiation and expansion can be predicted. Referring to fig. 22 and 23, under the action of the well production regime, changes in parameters such as pressure and stress in the reservoir result in the propagation of the original two fractures into larger scale fractures.

From the above description, the unstructured dynamic mesh generation method provided by the application can generate an oil reservoir pressure value according to the dynamic mesh generation result.

Referring to fig. 7, before generating a reservoir pressure value according to the dynamic mesh generation result, the method includes:

s401: calculating the volume of each discrete crack grid according to the node coordinates of each discrete crack grid in the three-dimensional geological model;

it can be understood that, since the three-dimensional geological model includes node coordinate information of each discrete fracture grid, and the discrete fracture grids are generally in various standard geometric shapes or combinations thereof, the volume of each discrete fracture grid can be calculated by a basic mathematical geometric method.

S402: acquiring the porosity of each discrete crack grid in the three-dimensional geological model and the central point of each discrete crack grid;

it can be understood that the three-dimensional geological model includes the porosity information of each discrete fracture grid and the central point information of each discrete fracture grid.

S403: and obtaining the depth value of each discrete fracture grid according to the central point of each discrete fracture grid.

It can be understood that the Z-axis coordinate of the central point of each discrete fracture grid is the depth value of each discrete fracture grid, and the Z-axis coordinate of the central point of each discrete fracture grid can be directly obtained in the three-dimensional geological model.

From the above description, the unstructured dynamic mesh generation method provided by the present application can obtain the volume of each discrete fracture mesh, the porosity of each discrete fracture mesh, the central point of each discrete fracture mesh, and the depth value of each discrete fracture mesh.

Referring to fig. 8, the calculating the conductivity of the adjacent discrete fracture grids in the corresponding region of the three-dimensional geological model according to the dynamic grid splitting result and the three-dimensional geological model includes:

s501: calculating the conductivity between the matrix and the cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result, the length from the grid center point to the grid connection surface center point, the unit normal vector of the grid connection surface pointing to the grid and the unit direction vector of the grid connection surface center point pointing to the grid center point;

s502: and calculating the conductivity between the adjacent cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result and the distance between the grid central points.

It is understood that the specific implementation of S501 to S502 can be referred to S301.

From the above description, it can be known that the unstructured dynamic mesh generation method provided by the present application can calculate the conductivity of the adjacent discrete fracture meshes in the corresponding region of the three-dimensional geological model according to the dynamic mesh generation result and the three-dimensional geological model.

Referring to fig. 9, the pressure values include pore pressure values, and updating the discrete fractures based on the reservoir pressure values includes:

s601: calculating a rock fracture pressure threshold according to the pore pressure numerical value and overburden pressure, poisson's ratio, a geological structure stress coefficient and tensile strength in the three-dimensional geological model;

s602: calculating a fracture extension pressure threshold according to the minimum horizontal principal stress, the fracture surface energy, the elastic modulus and the fracture half-length in the three-dimensional geological model;

s603: and updating the discrete fractures according to the current fracture form, the rock fracture pressure threshold, the fracture extension pressure threshold, the space stress field of the region corresponding to the three-dimensional geological model and the pore pressure field.

It is understood that the steps corresponding to S601 to S603 can be referred to as S302.

From the above description, the unstructured dynamic mesh generation method provided by the application can update discrete fractures according to the reservoir pressure value.

In an embodiment, after updating the dynamic mesh generation result based on the updated discrete fracture, the method further includes: and carrying out grid attribute migration according to the updated dynamic grid generation result.

It can be understood that when the dynamic mesh generation result is updated, boundary information, fracture information, matrix information and the like of a region corresponding to the three-dimensional geological model need to be extracted, and the specific analysis and extraction steps are as follows:

1) Extracting current unstructured grid information, analyzing node space information of each matrix grid, counting the number of adjacent grids of each grid surface, and recording as N _nb Since the number of junctions between the grid near the center of the region and the adjacent grids may be relatively large, see fig. 24. Thus, all of N _nb And the polygons of =1 or 2 are the outer envelope surfaces of the meshes, so that the boundary information of the region corresponding to the three-dimensional geological model can be judged. Of course, this boundary information may also be derived from the boundary information of the three-dimensional geological model in step S101, and in step S101, the boundary information of the three-dimensional geological model may also be calculated by the above method, that is, in the unstructured dynamic mesh generation method provided in this application, the boundary information of the three-dimensional geological model may not be changed.

2) And (4) obtaining an updated fracture pattern according to the boundary information of the three-dimensional geological model and calculation in S301-S302, and executing the step S101 again to complete mesh division, so that a mesh division result can be dynamically updated, and the fracture mesh can be marked during division, so that the fracture information can be continuously extracted in the next time step. Fig. 23 is a division result of the mesh division performed according to fig. 22.

3) Grid attribute migration

After the dynamic mesh generation result is updated based on the updated discrete fracture, the mesh attributes are migrated according to the updated dynamic mesh generation result.

After the mesh generation is updated, mapping the parameters for numerical simulation obtained by the last time step, namely the boundary information of the three-dimensional geological model and the fracture pattern obtained by calculation in S301 to S302, into a new mesh generation result, wherein the matrix parameters are mapped by the following formula:

wherein x is the name of the mapping attribute, I is the number of the new grid, I is the number of the old grid, c _i Is the volume fraction of the grid block I that falls within grid block I. Fig. 25 is the results after matrix mesh permeability mapping.

The permeability of the crack needs to be obtained by adopting a specific calculation method, and the specific steps are as follows:

firstly, determining the opening degree of a crack:

d＝0.01×L ^0.5

wherein d is the opening degree and L is the crack length. Since the fracture is much less open than its length and height, the permeability k of the fracture can be determined using a fluid flow model in an infinite plate. If the opening of the crack is d and the height is d, the method comprises the following steps of:

in the case of fracture filling variation, the permeability should be multiplied by a corresponding correction factor. The correction factor is generally fitted according to the oil reservoir production dynamic state, namely the permeability attribute of the fracture is gradually adjusted until the oil reservoir numerical simulation calculation oil reservoir production condition is compared with the real production dynamic state result to achieve a certain goodness of fit.

FIG. 26 is a diagram of an unstructured grid and a corresponding unstructured grid model in an embodiment of the present application.

In one embodiment, referring to fig. 27-34, the example application well group model is located in an ultra-low permeability reservoir in a basin, the main stress direction of the work area is about 75 ° in the north east, and the natural fracture trend is 67.5 ° to 70 °. The comprehensive water content of a single well is 2.5% in the initial development stage, and the comprehensive water content rises to 85.5% along with the water injection development in the later development stage.

The work area adopts an automatic unstructured grid subdivision and dynamic update method, a construction model and an attribute model are established at an initial moment, discrete cracks are dynamically added in the digital-analog process, and unstructured grids and corresponding attributes are updated in real time.

The result of fitting and matching the dynamic fracture and the single well is shown in the following graph, and from the production dynamic curve of 3 key wells and the rising time of water content, the error rate does not exceed 10%, the goodness of fit is high, and the reliability and the adaptability of the technology are proved.

Based on the same inventive concept, the embodiment of the present application further provides an unstructured dynamic mesh generation device, which can be used to implement the method described in the foregoing embodiment, as described in the following embodiment. Because the problem solving principle of the unstructured dynamic mesh generation device is similar to that of the unstructured dynamic mesh generation method, the implementation of the unstructured dynamic mesh generation device can refer to the implementation of a software performance reference determination method, and repeated parts are not described again. As used hereinafter, the term "unit" or "module" may be a combination of software and/or hardware that implements a predetermined function. While the system described in the embodiments below is preferably implemented in software, implementations in hardware, or a combination of software and hardware are also possible and contemplated.

Referring to fig. 10, in order to update the dynamic mesh generation result according to the dynamic mesh generation parameters and realize dynamic high-efficiency mesh generation, the present application provides an unstructured dynamic mesh generation apparatus, including:

a generation unit 1001 for generating a dynamic mesh generation result according to the dynamic mesh generation parameter; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometrical information and quality control parameters;

a pressure value generating unit 1002, configured to generate an oil reservoir pressure value according to the dynamic grid generation result;

a discrete fracture updating unit 1003, configured to update a discrete fracture according to the reservoir pressure value;

and a partitioning result updating unit 1004 for updating the dynamic mesh partitioning result based on the updated discrete fracture.

Referring to fig. 11, the subdivision result generation unit 1001 includes:

the POLY data generation module 1101 is used for generating POLY data according to the three-dimensional geological model boundary information and the discrete fracture grid geometric information; the POLY data includes: boundary crack node data, boundary crack face data, boundary crack hole data and boundary crack partition data;

a subdivision result generation module 1102, configured to invoke the POLY data to generate a dynamic mesh subdivision result according to the quality control parameter; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data.

Referring to fig. 12, the pressure value generation unit 1002 includes:

a conductivity calculation module 1201, configured to calculate, according to the dynamic mesh generation result and the three-dimensional geological model, conductivity of adjacent discrete fracture meshes in a region corresponding to the three-dimensional geological model;

a pressure value generation module 1202 for predicting a reservoir pressure value according to the conductivity of the adjacent discrete fracture grid.

Referring to fig. 13, the unstructured dynamic mesh generation apparatus further includes:

the volume calculation unit 1301 is used for calculating the volume of each discrete fracture grid according to the node coordinates of each discrete fracture grid in the three-dimensional geological model;

a porosity central point obtaining unit 1302, configured to obtain the porosity of each discrete fracture grid and the central point of each discrete fracture grid in the three-dimensional geological model;

and the depth value generating unit 1303 is configured to obtain a depth value of each discrete fracture grid according to the central point of each discrete fracture grid.

Referring to fig. 14, the conductivity calculation module 1201 includes:

a conductivity between seam-based calculation module 1401, configured to calculate conductivity between the matrix and the crack according to the permeability of the grid in the three-dimensional geological model, the mesh connection area in the dynamic mesh generation result, the length from the center point of the grid to the center point of the mesh interface, the unit normal vector of the mesh interface pointing to the grid, and the unit direction vector of the center point of the mesh interface pointing to the center point of the grid;

and the conductivity calculation module 1402 for adjacent fractures is used for calculating the conductivity between adjacent fractures according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result and the distance between the grid center points.

Referring to fig. 15, the pressure values include pore pressure values, and the discrete fracture updating unit 1003 includes:

a fracture pressure threshold determination module 1501, configured to calculate a rock fracture pressure threshold according to the pore pressure value and overburden pressure, poisson's ratio, geological structure stress coefficient, and tensile strength in the three-dimensional geological model;

an extension pressure threshold determination module 1502 for calculating a fracture extension pressure threshold from a minimum horizontal principal stress, a fracture surface energy, an elastic modulus, and a fracture half-length in the three-dimensional geological model;

and the discrete fracture updating module 1503 is used for updating discrete fractures according to the current fracture form, the rock fracture pressure threshold, the fracture extension pressure threshold, and the spatial stress field and the pore pressure field of the region corresponding to the three-dimensional geological model.

The discrete fracture updating unit 1003 is further specifically configured to:

In order to update the dynamic mesh generation result according to the dynamic mesh generation parameters and realize dynamic and efficient mesh generation in a hardware level, the present application provides an embodiment of an electronic device for realizing all or part of contents in the unstructured dynamic mesh generation method, where the electronic device specifically includes the following contents:

a Processor (Processor), a Memory (Memory), a communication Interface (Communications Interface) and a bus; the processor, the memory and the communication interface complete mutual communication through the bus; the communication interface is used for realizing information transmission between the unstructured dynamic mesh generation device and relevant equipment such as a core service system, a user terminal, a relevant database and the like; the logic controller may be a desktop computer, a tablet computer, a mobile terminal, and the like, but the embodiment is not limited thereto. In this embodiment, the logic controller may be implemented with reference to the unstructured dynamic mesh generation method in the embodiment and the unstructured dynamic mesh generation apparatus, and the contents thereof are incorporated herein, and repeated descriptions thereof are omitted.

It is understood that the user terminal may include a smart phone, a tablet electronic device, a network set-top box, a portable computer, a desktop computer, a Personal Digital Assistant (PDA), a vehicle-mounted device, a smart wearable device, and the like. Wherein, intelligence wearing equipment can include intelligent glasses, intelligent wrist-watch, intelligent bracelet etc..

In practical applications, part of the unstructured dynamic mesh generation method may be performed at the electronic device side as described above, or all operations may be performed at the client device. The selection may be specifically performed according to the processing capability of the client device, the limitation of the user usage scenario, and the like. This is not a limitation of the present application. The client device may further include a processor if all operations are performed in the client device.

The client device may have a communication module (i.e., a communication unit), and may be in communication connection with a remote server to implement data transmission with the server. The server may include a server on the side of the task scheduling center, and in other implementation scenarios, the server may also include a server on an intermediate platform, for example, a server on a third-party server platform that is communicatively linked to the task scheduling center server. The server may include a single computer device, or may include a server cluster formed by a plurality of servers, or a server structure of a distributed apparatus.

Fig. 16 is a schematic block diagram of a system configuration of an electronic device 9600 according to the embodiment of the present application. As shown in fig. 16, the electronic device 9600 can include a central processor 9100 and a memory 9140; the memory 9140 is coupled to the central processor 9100. Notably, this fig. 16 is exemplary; other types of structures may also be used in addition to or in place of the structure to implement telecommunications or other functions.

In an embodiment, the unstructured dynamic mesh generation method functionality may be integrated into the central processor 9100. The central processor 9100 can be configured to perform the following control:

From the above description, the unstructured dynamic mesh generation method provided by the application can update the dynamic mesh generation result according to the dynamic mesh generation parameters, so that the mesh model can be dynamically updated according to the crack initiation, expansion and closing, and is matched with the actual crack network in real time, and the high-precision discrete crack model is applied to the oil field with dynamic crack expansion, the fine simulation of the crack dynamic change process in the low-permeability long-term water injection process is realized, and a powerful tool is provided for the precise prediction, fine management and scheme optimization of the low-permeability oil reservoir development.

In another embodiment, the unstructured dynamic meshing device may be configured separately from the central processor 9100, for example, the unstructured dynamic meshing device of the data composite transmission apparatus may be configured as a chip connected to the central processor 9100, and the function of the unstructured dynamic meshing method may be realized by the control of the central processor.

As shown in fig. 16, the electronic device 9600 may further include: a communication module 9110, an input unit 9120, an audio processor 9130, a display 9160, and a power supply 9170. It is noted that the electronic device 9600 also does not necessarily include all of the components shown in fig. 16; further, the electronic device 9600 may further include components not shown in fig. 16, which can be referred to in the related art.

As shown in fig. 16, a central processor 9100, sometimes referred to as a controller or operational control, can include a microprocessor or other processor device and/or logic device, which central processor 9100 receives input and controls the operation of the various components of the electronic device 9600.

The memory 9140 can be, for example, one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, or other suitable device. The information relating to the failure may be stored, and a program for executing the information may be stored. And the central processing unit 9100 can execute the program stored in the memory 9140 to realize information storage or processing, or the like.

The input unit 9120 provides input to the central processor 9100. The input unit 9120 is, for example, a key or a touch input device. Power supply 9170 is used to provide power to electronic device 9600. The display 9160 is used for displaying display objects such as images and characters. The display may be, for example, an LCD display, but is not limited thereto.

The memory 9140 can be a solid state memory, e.g., read Only Memory (ROM), random Access Memory (RAM), a SIM card, or the like. There may also be a memory that holds information even when power is off, can be selectively erased, and is provided with more data, an example of which is sometimes called an EPROM or the like. The memory 9140 could also be some other type of device. The memory 9140 includes a buffer memory 9141 (sometimes referred to as a buffer). The memory 9140 may include an application/function storage portion 9142, the application/function storage portion 9142 being used for storing application programs and function programs or for executing a flow of operations of the electronic device 9600 by the central processor 9100.

The memory 9140 can also include a data store 9143, the data store 9143 for storing data, such as contacts, digital data, pictures, sounds, and/or any other data used by the electronic device. The driver storage portion 9144 of the memory 9140 may include various drivers of the electronic device for communication functions and/or for performing other functions of the electronic device (e.g., messaging applications, contact book applications, etc.).

The communication module 9110 is a transmitter/receiver 9110 that transmits and receives signals via an antenna 9111. The communication module (transmitter/receiver) 9110 is coupled to the central processor 9100 to provide input signals and receive output signals, which may be the same as in the case of a conventional mobile communication terminal.

Based on different communication technologies, a plurality of communication modules 9110, such as a cellular network module, a bluetooth module, and/or a wireless lan module, may be disposed in the same electronic device. The communication module (transmitter/receiver) 9110 is also coupled to a speaker 9131 and a microphone 9132 via an audio processor 9130 to provide audio output via the speaker 9131 and receive audio input from the microphone 9132 to implement general telecommunications functions. The audio processor 9130 may include any suitable buffers, decoders, amplifiers and so forth. In addition, the audio processor 9130 is also coupled to the central processor 9100, thereby enabling recording locally through the microphone 9132 and enabling locally stored sounds to be played through the speaker 9131.

An embodiment of the present application further provides a computer-readable storage medium capable of implementing all steps in the unstructured dynamic mesh generation method in which the execution subject is the server or the client in the foregoing embodiment, where the computer-readable storage medium stores a computer program thereon, and when the computer program is executed by a processor, the computer program implements all steps of the unstructured dynamic mesh generation method in which the execution subject is the server or the client, for example, when the processor executes the computer program, the processor implements the following steps:

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, apparatus, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (devices), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may 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, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The principle and the implementation mode of the invention are explained by applying specific embodiments in the invention, and the description of the embodiments is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. An unstructured dynamic mesh generation method, comprising:

generating a dynamic mesh generation result according to the dynamic mesh generation parameters; the dynamic mesh generation parameters comprise three-dimensional geological model boundary information, discrete fracture mesh geometric information and quality control parameters;

updating the discrete fractures according to the oil reservoir pressure value;

updating the dynamic mesh generation result based on the updated discrete fracture;

the generating of the dynamic mesh generation result according to the dynamic mesh generation parameters includes:

generating POLY data according to the three-dimensional geological model boundary information and the discrete fracture grid geometrical information; the POLY data includes: boundary crack node data, boundary crack face data, boundary crack hole data and boundary crack partition data;

calling the POLY data to generate a dynamic mesh generation result according to the quality control parameters; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data;

wherein, the generating of the oil reservoir pressure value according to the dynamic mesh generation result comprises:

calculating the conductivity of adjacent discrete crack grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model;

predicting a reservoir pressure value according to the conductivity of the adjacent discrete fracture grids;

the method for calculating the conductivity of the adjacent discrete crack grids in the corresponding area of the three-dimensional geological model according to the dynamic grid subdivision result and the three-dimensional geological model comprises the following steps:

2. The unstructured dynamic meshing method according to claim 1, comprising, before generating reservoir pressure values from the dynamic meshing results:

acquiring the porosity of each discrete fracture grid and the central point of each discrete fracture grid in the three-dimensional geological model;

3. The unstructured dynamic meshing method of claim 1, wherein the pressure values comprise pore pressure values, and updating discrete fractures based on the reservoir pressure values comprises:

4. The unstructured dynamic meshing method of claim 1, further comprising, after updating the dynamic meshing results based on the updated discrete fractures:

5. An unstructured dynamic mesh generation apparatus, comprising:

the pressure value generating unit is used for generating an oil deposit pressure value according to the dynamic grid subdivision result;

the subdivision result updating unit is used for updating the dynamic mesh subdivision result based on the updated discrete fracture;

wherein, the subdivision result generation unit comprises:

the subdivision result generation module is used for calling the POLY data to generate a dynamic mesh subdivision result according to the quality control parameter; the dynamic mesh generation result comprises mesh node data, mesh edge data, mesh surface data, mesh tetrahedron data and mesh tetrahedron adjacent data;

wherein the pressure value generation unit includes:

the pressure value generation module is used for predicting the reservoir pressure value according to the conductivity of the adjacent discrete fracture grids;

wherein the conductivity calculation module comprises:

the conductivity calculation module between the base seams is used for calculating the conductivity between the matrix and the cracks according to the grid permeability in the three-dimensional geological model, the grid connection area in the dynamic grid subdivision result, the length from the grid center point to the grid connection surface center point, the unit normal vector of the grid connection surface pointing to the grid and the unit direction vector of the grid connection surface center point pointing to the grid center point;

6. The unstructured dynamic meshing device of claim 5, further comprising:

7. The unstructured dynamic meshing device of claim 5, wherein the pressure values comprise pore pressure values, and the discrete fracture update unit comprises:

the extension pressure threshold determination module is used for calculating a fracture extension pressure threshold according to the minimum horizontal principal stress, the fracture surface energy, the elastic modulus and the fracture half-length in the three-dimensional geological model;

8. The unstructured dynamic meshing device of claim 5, wherein the discrete fracture update unit is further specifically configured to:

9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the unstructured dynamic mesh generation method of any of claims 1 to 4 when executing the program.

10. A computer-readable storage medium, on which a computer program is stored, which computer program, when being executed by a processor, is adapted to carry out the steps of the unstructured dynamic mesh generation method of one of the claims 1 to 4.