CN114239431B

CN114239431B - Simulation method, device and equipment for water flooding of fracture development reservoir

Info

Publication number: CN114239431B
Application number: CN202111486586.3A
Authority: CN
Inventors: 贾品; 郭红鑫; 曹冲; 程林松; 王鹏
Original assignee: China University of Petroleum Beijing
Current assignee: China University of Petroleum Beijing
Priority date: 2021-12-07
Filing date: 2021-12-07
Publication date: 2022-08-26
Anticipated expiration: 2041-12-07
Also published as: CN114239431A

Abstract

The embodiment of the specification discloses a simulation method, a device and equipment for water flooding of a fractured reservoir, which are characterized in that a matrix is divided into a plurality of linear sub-regions based on water flooding displacement streamline characteristics of fractured cores with different shapes in the fractured reservoir, a two-dimensional problem of water flooding is converted into a one-dimensional linear sub-region coupling solving problem, a research region is divided into an injection region, a fractured region and a production region, corresponding linear flow models are respectively created, the linear flow models are sequentially solved, a linear displacement analytical solution of the matrix region at an injection end, a fracture linear diversion numerical value solution, a matrix displacement analytical solution at an outlet end are solved, linear flows of the matrix and a fracture system are coupled, the two-dimensional problem of water flooding is converted into a one-dimensional linear sub-region coupling solving problem, a three-region linear flow semi-analytical solution of water flooding of the fractured core is obtained, and further a pressure distribution and a saturation distribution of the fractured reservoir are obtained, the accurate simulation of the water flooding process of the crack development reservoir is realized.

Description

Simulation method, device and equipment for water flooding of fracture development reservoir

Technical Field

The specification belongs to the technical field of oil and gas exploitation, and particularly relates to a method, a device and equipment for simulating water flooding of a fracture development reservoir.

Background

In the process of water flooding development of an oil field, a fractured reservoir has large difference from a conventional reservoir in the aspects of fluid distribution rule, fracture development characteristics, reservoir heterogeneity and other water flooding development characteristics, so that the water flooding research of the fractured reservoir is different from the conventional reservoir, particularly, the influence of different types of productive fractures (including high-angle fractures and low-angle fractures) on the water flooding rule is unknown, and the research difficulty is far higher than that of the conventional reservoir.

At present, physical simulation experiments or numerical simulation are generally adopted for simulating the oil-water displacement process, but the physical simulation experiments are difficult to depict any fracture in an occurrence shape, and the numerical simulation depicts the fracture by dividing a complex grid, so that the calculation efficiency is low.

Therefore, how to provide a scheme capable of accurately describing the process of water flooding is a technical problem to be solved urgently in the field.

Disclosure of Invention

An embodiment of the specification aims to provide a method, a device and equipment for simulating water flooding of a fracture development reservoir, so that the accuracy of simulation of the water flooding of the fracture development reservoir is improved.

In one aspect, an embodiment of the present specification provides a method for simulating water flooding of a fracture development reservoir, where the method includes:

the method comprises the following steps:

discretely dividing a matrix in a dual medium model corresponding to a fracture development reservoir to be processed into a plurality of one-dimensional linear subregions according to fracture occurrence distribution in the fracture development reservoir to be processed, wherein each one-dimensional linear subregion comprises fracture microelements;

dividing each one-dimensional linear sub-region into an injection region, a fracture region and a production region, and respectively establishing a trilinear flow model corresponding to each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region and the production region, wherein the trilinear flow model comprises the following steps: an injection zone linear flow model, a fracture zone linear flow model and a production zone linear flow model;

sequentially solving the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion to obtain the oil-water flow of the injection region, the pressure distribution of the injection region, the saturation distribution of the injection region and the oil-water flow of the extraction region, the pressure distribution of the extraction region and the saturation distribution of the extraction region corresponding to each one-dimensional linear subregion;

sequentially solving a fracture area linear flow model in a trilinear flow model corresponding to each one-dimensional linear sub-area based on the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear sub-area to obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear sub-area;

and simulating a saturation field and a pressure field of the developed reservoir of the fracture to be treated according to the obtained fracture pressure, the fracture water saturation, the injection area pressure distribution, the injection area saturation distribution, the extraction area pressure distribution and the extraction area saturation distribution.

Further, the establishing a trilinear flow model corresponding to each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region, and the production region includes:

establishing an injection zone linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion according to the following formula:

initial conditions: p is a radical of _m | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi

Inner boundary conditions:

outer boundary conditions:

wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear sub-regions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is water-bearingSaturation, t is time, S _oi Is the original oil saturation, q _w Water injection quantity, L, for a single one-dimensional linear subregion _L As the position of the crack, p _f Is the pressure of the fracture.

establishing a fracture area linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-area according to the following formula:

initial conditions: p is a radical of formula _f | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi

Inner boundary conditions:

outer boundary conditions:

wherein k is _f Absolute permeability of crack, k _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase,. epsilon.is the crack extension direction, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, q _o,L Amount of oil supplied to the injection zone per unit volume, q _o,R The amount of oil supplied to the production zone per unit volume is negative, q _w,L The amount of water supplied per unit volume of the injection zone, q _w,R The amount of water supplied to the production zone per unit volume is negative, S _o Is the oil saturation, S _w Is the water saturation, t is time, S _oi Is the original oil saturation, p _f Pressure of the fracture, p _i Denotes the initial pressure, L _f Indicating the total length of the fracture, the inner and outer boundaries of the fracture being closed boundaries.

establishing a linear flow model of the extraction area in the trilinear flow model corresponding to each one-dimensional linear subregion according to the following formula:

initial conditions were as follows: p is a radical of formula _m | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi

Inner boundary conditions:

outer boundary conditions: p is a radical of _m | _x＝L ＝p _w

Wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear sub-regions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, q _w Water injection quantity, L, for a single one-dimensional linear subregion _L As the position of the crack, p _w Is the outlet end pressure.

Further, the sequentially solving the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-region includes:

and (3) adopting the corrected BL equation to carry out displacement solution on the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-region.

Further, the sequentially solving the linear flow model of the fracture zone in the trilinear flow model corresponding to each one-dimensional linear sub-zone based on the oil-water flow of the injection zone and the oil-water flow of the extraction zone corresponding to each one-dimensional linear sub-zone includes:

and on the basis of the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear subregion, solving the linear flow model of the crack area in the trilinear flow model corresponding to each one-dimensional linear subregion in sequence by adopting a full-implicit finite volume method.

Further, the discretely dividing the matrix in the dual medium model corresponding to the fracture development reservoir to be processed into a plurality of one-dimensional linear sub-regions according to the fracture occurrence distribution in the fracture development reservoir to be processed includes:

and dispersing the matrix in the dual medium model corresponding to the fracture development reservoir to be treated into a plurality of one-dimensional linear sub-regions along the length direction of the fracture according to the fracture occurrence distribution in the fracture development reservoir to be treated, wherein fracture microelements in each one-dimensional linear sub-region are dispersed into linear fractures.

In another aspect, the present disclosure provides an apparatus for simulating waterflood in a fracture-developing reservoir, the apparatus comprising:

the subarea dividing module is used for discretely dividing the matrix in the dual medium model corresponding to the fracture development reservoir to be processed into a plurality of one-dimensional linear subareas according to the fracture occurrence distribution in the fracture development reservoir to be processed, wherein each one-dimensional linear subarea comprises fracture microelements;

the linear flow model creating module is used for dividing each one-dimensional linear sub-region into an injection region, a fracture region and a production region, and respectively establishing a trilinear flow model corresponding to each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region and the production region, wherein the trilinear flow model comprises: an injection zone linear flow model, a fracture zone linear flow model and a production zone linear flow model;

the oil-water flow calculation module is used for sequentially solving the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion to obtain the oil-water flow, the injection region pressure distribution, the injection region saturation distribution and the extraction region oil-water flow, the extraction region pressure distribution and the extraction region saturation distribution of the injection region corresponding to each one-dimensional linear subregion;

the pressure saturation solving module is used for sequentially solving the fracture area linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-area based on the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear sub-area to obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear sub-area;

and the water drive simulation module is used for simulating a saturation field and a pressure field of the to-be-treated fracture development reservoir according to the obtained fracture pressure, the fracture water saturation, the injection area pressure distribution, the injection area saturation distribution, the production area pressure distribution and the production area saturation distribution.

In another aspect, the present specification provides a water flooding simulation apparatus for a fracture development reservoir, where the apparatus includes at least one processor and a memory for storing processor executable instructions, and the instructions, when executed by the processor, implement a simulation method for water flooding of the fracture development reservoir.

The simulation method, device and equipment for water flooding of a fractured developmental reservoir provided by the specification are characterized in that a matrix is divided into a plurality of linear sub-regions based on water flooding displacement streamline characteristics of fractured cores with different shapes in a fractured reservoir, a water flooding two-dimensional problem is converted into a one-dimensional linear sub-region coupling solving problem, each linear sub-region is divided into an injection region, a fractured region and a production region, corresponding linear flow models are respectively created according to the flow characteristics of the injection region, the fractured region and the production region, each linear flow model is sequentially solved, a linear displacement analytical solution of the matrix region at an injection end, a fracture linear diversion numerical solution, an outlet end matrix displacement analytical solution are solved, the matrix and the fracture system linear flow are coupled, the water flooding two-dimensional problem is converted into the one-dimensional linear sub-region coupling solving problem, and a water flooding three-region linear flow semi-analytical solution of the fractured core is obtained, and further, the pressure distribution and the saturation distribution of the fracture development reservoir are obtained, and the accurate simulation of the water flooding process of the fracture development reservoir is realized.

Drawings

In order to more clearly illustrate the embodiments of the present specification or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the description below are only some embodiments described in the present specification, and for those skilled in the art, other drawings may be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic flow chart diagram of an embodiment of a simulation method for reservoir flooding in a fracture development reservoir provided in an embodiment of the present disclosure;

FIG. 2 is a schematic illustration of the discretization of a substrate in one embodiment of the present disclosure;

FIG. 3 is a schematic illustration of trilinear flow and fracture discretization in one embodiment of the present description;

FIG. 4 is a schematic view of a low angle non-through seam flow line in one embodiment of the present disclosure;

FIG. 5 is a schematic illustration of injection zone flooding linear flow in one embodiment of the present description;

FIG. 6 is a schematic illustration of a fracture zone waterflood linear flow in one embodiment of the present description;

FIG. 7 is a schematic illustration of a production zone waterflood linear flow in one embodiment of the present description;

FIG. 8 is a schematic illustration of the conduction of a rectangular grid of two adjacent fracture micro-elements in one embodiment of the specification;

FIG. 9 is a flow diagram illustrating a solution flow of a tri-linear flow model in one embodiment of the present description;

FIG. 10 is a schematic diagram of a simulation apparatus for reservoir flooding in a fracture development reservoir according to an embodiment of the present disclosure;

fig. 11 is a block diagram of a hardware architecture of a simulation server for water flooding of a fracture development reservoir in an embodiment of the present disclosure.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present specification, the technical solutions in the embodiments of the present specification will be clearly and completely described below with reference to the drawings in the embodiments of the present specification, and it is obvious that the described embodiments are only a part of the embodiments of the present specification, and not all of the embodiments. All other embodiments obtained by a person skilled in the art based on the embodiments in the present specification without any inventive step should fall within the scope of protection of the present specification.

In a scenario example provided in an embodiment of the present specification, the method for simulating water flooding of a fracture development reservoir may be applied to a device for performing simulation of water flooding of a fracture development reservoir, where the device may include one server or a server cluster formed by a plurality of servers.

The simulation method for water flooding of the fractured developmental reservoir provided in the embodiment of the description divides a matrix into a plurality of linear sub-regions based on water flooding displacement streamline characteristics of fractured cores with different shapes in the fractured reservoir, divides each linear sub-region into an injection region, a fractured region and a production region based on flow characteristics, respectively establishes a trilinear flow model for the injection region, the fractured region and the production region of each linear sub-region, and solves the trilinear flow model to obtain pressure distribution, saturation distribution and the like of the fractured developmental reservoir, so as to realize simulation of the water flooding process of the fractured developmental reservoir. The method can flexibly depict fractures with any dip angle, quantitatively calculate water flooding indexes (oil displacement efficiency, water content and the like) under different fracture conditions, realize simulation of a water displacement saturation field and a pressure field, and provide a new method for efficient simulation of water displacement of the fractured reservoir.

Fig. 1 is a schematic flow chart of an embodiment of a simulation method for reservoir flooding of a fracture development reservoir provided in an embodiment of the present disclosure. Although the present specification provides the method steps or apparatus structures as shown in the following examples or figures, more or less steps or modules may be included in the method or apparatus after being partially combined based on conventional or non-inventive efforts. In the step or structure where there is no necessary causal relationship logically, the execution sequence of these steps or the module structure of the apparatus is not limited to the execution sequence or module structure shown in the embodiment or the drawings, and when the method or module structure shown in the embodiment or the drawings is applied to an actual apparatus, server or end product, the method or module structure shown in the embodiment or the drawings may be executed sequentially or executed in parallel (for example, in the environment of parallel processors or multi-thread processing, or even in the environment of implementation including distributed processing and server clustering).

In a specific embodiment of the method for simulating water flooding of a fracture development reservoir provided in the present specification, as shown in fig. 1, the method may be applied to a server, a computer, a smart phone, a tablet computer, and the like, and the method may include the following steps:

step 102, discretely dividing a matrix in a dual medium model corresponding to a fracture development reservoir to be processed into a plurality of one-dimensional linear sub-regions according to fracture occurrence distribution in the fracture development reservoir to be processed, wherein each one-dimensional linear sub-region comprises fracture microelements.

In a specific implementation, a fractured reservoir can be generally simplified to a dual media system, consisting of a matrix and fractures, where the pores are the primary storage space for fluids and the fractures are the primary flow channels for fluids. Generally, the permeability of the matrix is small, the porosity is large, the permeability of the fracture is large, the porosity is small, two parallel seepage fields exist in the same moment, and fluid exchange exists between the two seepage fields, and the fluid exchange is called cross flow between the matrix fractures. In the embodiment of the description, the matrix in the dual medium model corresponding to the fracture development reservoir to be processed may be discretely divided into a plurality of one-dimensional linear sub-regions according to the fracture occurrence distribution in the fracture development reservoir to be processed, after the matrix is discretized, the fractures in the matrix are also discretized, and each one-dimensional linear sub-region may include corresponding fracture microelements. For example: the substrate may be discretely divided into a plurality of one-dimensional linear subregions along the direction of the crack distribution in such a manner that the thickness of each linear subregion is preset or the number of linear subregions is preset. Typically, the width or thickness of each linear sub-region is the same. The number and size of the linear sub-regions may be set according to actual needs, and the embodiments of the present specification are not particularly limited.

In some embodiments of the present specification, the discretely dividing a matrix in a dual medium model corresponding to a fracture development reservoir to be processed into a plurality of one-dimensional linear sub-regions according to fracture occurrence distribution in the fracture development reservoir to be processed includes:

In a specific implementation process, fig. 2 is a schematic diagram of matrix discretization in an embodiment of the present specification, and as shown in fig. 2, in the embodiment of the present specification, assuming that there is one fracture in the matrix of the fracture development reservoir to be treated, the matrix of the fracture development reservoir to be treated may be discretized into a plurality of one-dimensional linear sub-regions along the length direction of the fracture based on the fracture occurrence distribution in the fracture development reservoir to be treated. Each rectangular box in fig. 2 can be understood as a linear sub-region, as shown in fig. 2, there is a vertical line in each linear sub-region, and the vertical line can be understood as a fracture infinitesimal in each linear sub-region, and in general, the fracture is a slope, in this embodiment of the present specification, by discretizing the matrix, when there are enough linear sub-regions, each linear sub-region is sufficiently narrow, and at this time, the fracture in each linear sub-region can be approximately understood as a straight fracture, as shown in fig. 2, so that data processing can be facilitated, and the efficiency and accuracy of data processing can be improved when modeling and solving.

Step 104, dividing each one-dimensional linear sub-area into an injection area, a fracture area and a production area, and respectively establishing a trilinear flow model corresponding to each one-dimensional linear sub-area according to the flow characteristics corresponding to the injection area, the fracture area and the production area, wherein the trilinear flow model comprises the following steps: an injection zone linear flow model, a fracture zone linear flow model and a production zone linear flow model.

In a specific implementation process, fig. 3 is a schematic diagram of trilinear flow and fracture discretization in an embodiment of the present description, as shown in fig. 3, based on the flow characteristics of different fracture-productive cores, that is, the injected fluid flows linearly from the inlet end substrate to the fracture horizontally, then flows linearly from the fracture zone, and finally the outlet end also shows a horizontal linear flow state, which may be referred to as "trilinear flow". According to the trilinear flow characteristics of different fracture conditions, the matrix is divided into a plurality of one-dimensional linear subregions from top to bottom, and the cross flow effect among the subregions is considered. When the matrix is dispersed, the cracks are dispersed into the same number of crack micro-elements, the cracks can be divided into the same number of crack micro-elements along with the sub-area of the matrix by combining the water displacement flow characteristics of the cracks with different shapes, and the flow guide effect among the crack micro-elements is considered. Fig. 4 is a schematic diagram of a low-angle non-through seam flow line in an embodiment of the present specification, where, as shown in fig. 4, an injection fluid exhibits a trilinear flow pattern from an inlet end to an outlet end, based on which, the embodiment of the present specification divides each one-dimensional linear sub-region into an injection region, a fracture region, and a production region, and combines the water-oil flow characteristics of each region and the channeling effect between each sub-region to respectively establish a trilinear flow model corresponding to each one-dimensional linear sub-region, where each trilinear flow model includes: an injection zone linear flow model, a fracture zone linear flow model and a production zone linear flow model. The injection zone linear flow model, the fracture zone linear flow model and the production zone linear flow model can be understood as mathematical models capable of representing the water flooding and the geological features of the corresponding zones.

In order to explore the influence of fractures with different shapes on the water flooding rule, the embodiment of the specification can consider different fracture dip angles to analyze the distribution of residual oil after water flooding, the difference of a saturation field and a streamline field so as to explore the water flooding utilization rule of a fractured reservoir.

In some embodiments of the present disclosure, the establishing a trilinear flow model corresponding to each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region, and the production region respectively includes:

initial conditions: p is a radical of _m | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi (2)

Inner boundary conditions:

outer boundary conditions:

wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear subregions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, q _w The water injection quantity of a single one-dimensional linear subregion is the sum of the water injection quantities of all the one-dimensional linear subregions, and the constant injection quantity Q and L are _L As the position of the crack, p _f Is the pressure of the fracture.

In a specific implementation process, the precondition of the trilinear flow model, namely a fractured reservoir water flooding physical model, can be established firstly:

(a) the matrix is isotropic and the permeability is K _m The inside of the crack is also isotropic, and the permeability is K _f ；

(b) The core and the fluid are incompressible and flow isothermally, and the Darcy law is met;

(c) neglecting capillary and gravitational forces;

(d) at time t-0, irreducible water saturation is S _wc The pressure of the whole oil reservoir is equal everywhere and is the initial pressure P _i ；

(e) Considering the process of oil displacement by water, the injection end is constant flow Q injection water, and the outlet end is constant pressure P _w Oil and water viscosity of mu _o And mu _w 。

On the basis of the above preconditions, fig. 5 is a schematic diagram of water flooding linear flow of an injection region in an embodiment of the present specification, where L in fig. 5 represents a total length of a fracture, as shown in fig. 5, assuming that the injection region is constant flow Q injection water, and the water flooding linear flow in the matrix is as shown in fig. 5, for each one-dimensional linear sub-region, the oil-water two-phase satisfies the above formula (1), that is, an injection region linear flow model corresponding to each linear sub-region.

In other embodiments of this specification, the establishing a trilinear flow model for each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region, and the production region respectively includes:

establishing a fracture zone linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion according to the following formula:

initial conditions: p is a radical of _f | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi (6)

Inner edgeBoundary conditions are as follows:

outer boundary conditions:

In a specific implementation process, fig. 6 is a schematic diagram of a water-flooding linear flow in a fracture area in an embodiment of the present specification, where L is a total length of the fracture, and as shown in fig. 6, the fracture area communicates with the left and right substrates, and includes a fluid flowing into the left substrate and a fluid flowing out of the right substrate in addition to linear diversion in the fracture. Based on this, the oil-water two-phase control equation satisfied by the fracture region of each one-dimensional linear sub-region is formula (5) above, i.e., the linear flow model of the fracture region corresponding to each linear sub-region.

initial conditions were as follows: p is a radical of _m | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi (10)

Inner boundary conditions:

outer boundary conditions: p is a radical of _m | _x＝L ＝p _w (12)

Wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear subregions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, q _w Water injection quantity, L, for a single one-dimensional linear subregion _L As the position of the crack, p _w Is the outlet end pressure.

In a specific implementation process, fig. 7 is a schematic diagram of water flooding linear flow of the production region in an embodiment of the present specification, and in fig. 7, L represents a total length of the fracture, as shown in fig. 7, the production region is injected with oil and water simultaneously, and a total injection amount of the oil and water changes with time, based on which an oil-water two-phase control equation satisfied by the production region of each one-dimensional linear sub-region is the above equation (9), that is, a fracture region linear flow model corresponding to each linear sub-region.

In the embodiment of the specification, a trilinear flow model is established by dispersing matrixes and fractures, according to the water-oil flow distribution characteristics of each discretized sub-area and considering the flow channeling effect and the flow guiding effect among the sub-areas, and an accurate theoretical basis is laid for accurate simulation of a water-oil displacement process of a fracture development reservoir.

And 106, sequentially solving the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion to obtain the oil-water flow, the injection region pressure distribution, the injection region saturation distribution and the extraction region oil-water flow, the extraction region pressure distribution and the extraction region saturation distribution of the injection region corresponding to each one-dimensional linear subregion.

In a specific implementation process, the fracture zone is communicated with the matrixes on the left side and the right side, and besides linear diversion in the fracture, the fracture zone also comprises fluid flowing in from the matrix on the left end and fluid flowing out from the matrix on the right end.

In some embodiments of the present specification, sequentially solving the injection zone linear flow model and the extraction zone linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-region includes:

In a specific implementation process, a corrected BL (Buckley-levett, oil-water two-phase equation) equation may be used to perform displacement solution on the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-region, so as to obtain an analytic solution of the injection region linear flow model and the extraction region linear flow model. For example, for an injection region, which may be a single-phase water injection in a linear sub-region, according to the BL equation, the position where a certain isosaturation surface arrives at time t:

wherein x ₀ Is the position of the original oil-water interface, f _w '(s _w ) To be at water saturation of S _w Of the hour

wh is the area of the subregion.

Based on the equation of motion of the isosaturation surface, the position of the water drive front edge can be obtained by deforming the formula (13):

meanwhile, the injection region has:

p(t)-p _f (t)＝q _w R _L (t) (15)

relationship between flow rate of inflow cracks in injection area and water content:

wherein x is _f For water-flooding the leading edge position, S _wf Water saturation of the front edge, p (t) pressure at oil-water interface at core injection end, p _f (t) pressure at the fracture, R _L (t) is the seepage resistance at the injection end, f _w (L _L ) At a certain moment in time L _L And (6) treating the water content. The meanings of other parameters in the formula can refer to the descriptions of the above embodiments, and are not described herein again.

According to the formulas (14) to (16), the pressure of the injection end of the rock core, the pressure of the crack, the seepage resistance of the injection end and the water content curve (f) _w (S _w ) Can calculate the injection zone water flood front position x) _f Front edge water saturation S _wf Water content f at the micro-element part of the crack _w (L _L ) And the oil-water flow q of the injection region _o,L And q is _w,L . Specifically, the BL equation and the formula can be used to calculate the water flooding front edge position x of the injection region _f Leading edge water saturation S _wf Water content f at the micro-element part of the crack _w (L _L ) And solving to obtain the oil-water flow of the injection area. Wherein, the water drive front edge position x of the injection area is utilized _f Leading edge water saturation S _wf The saturation distribution at each location of the implanted region can be determined and R in the above formula can be calculated _L Further calculating the obtained q _w Then through f _w The oil flow rate is further determined. And the pressure distribution and saturation distribution of the injection region can be obtained by utilizing the linear flow model of the injection region based on the oil-water amount and the phase permeation curve of the injection region.

Similarly, for the production zone, within the linear sub-zone, the production zone is two identical streams of oil and water flowing out of the fracture, according to the BL equation, a certain isosaturation level position:

and (3) solving the position of the water drive front edge according to an isosaturation surface movement equation:

wherein S _wF Water saturation at the fracture, t _f The crack water breakthrough time, and:

q _R (t)＝q _o,R (t)+q _w,R (t) (19)

according to the principle of material balance:

and then combining with an isosaturation surface mobile equation to deduce a solving formula of the water saturation of the front edge:

wherein the content of the first and second substances,

the equation of motion of the extraction area:

q _R (t)R _L (t)＝p _w -p _f (t) (22)

wherein, the formula (18) is the deformation of the formula (17), and according to the formulas (18) to (22), the seepage resistance and the water content curve (f) of the extraction area are obtained through the pressure of the core extraction area, the pressure of the crack position and the seepage resistance and the water content curve of the extraction area _w (S _w ) Can calculate the water flood leading edge position x of the production area _f Front edge water saturation S _wf And the oil-water flow q of the production zone _w,R (t),q _o,R (t) of (d). Similarly, the pressure distribution and the saturation distribution of the extraction area can be obtained by utilizing the oil-water flow and the phase permeability curve of the extraction area and utilizing the linear flow model of the extraction area.

Namely, the injection region and the extraction region are solved to obtain the oil-water flow of the injection region and the extraction region, and then the oil-water flow obtained by solving is brought into the corresponding linear flow model, so that the pressure distribution and the saturation distribution of the corresponding region can be obtained.

In the embodiment of the specification, a BL equation is adopted to solve a matrix area, a matrix water flooding analytical solution is established, and an accurate data base is laid for water flooding simulation of a subsequent fracture development reservoir.

And 108, sequentially solving the fracture area linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion based on the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear subregion to obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear subregion.

In a specific implementation process, after the injection area and the extraction area in each one-dimensional linear sub-area are solved to obtain the oil-water flow of the injection area and the extraction area, the obtained oil-water flow of the injection area and the extraction area can be brought into the fracture area linear flow model of the corresponding one-dimensional linear sub-area, and then the fracture area linear flow model is solved to obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear sub-area.

In some embodiments of the present specification, sequentially solving a linear flow model of a fracture region in a trilinear flow model corresponding to each one-dimensional linear sub-region based on an oil-water flow rate of an injection region and an oil-water flow rate of a production region corresponding to each one-dimensional linear sub-region includes:

In a specific implementation process, the one-dimensional linear oil-water two-phase flow flowing from the injection zone and flowing from the extraction zone is increased by the fracture flow, and the fracture zone is solved by adopting a finite volume method in the embodiment of the specification. FIG. 8 is a schematic diagram illustrating the conduction of a rectangular grid of two adjacent fracture infinitesimal elements in one embodiment of the specification, Δ x in FIG. 8 _i Is the length of the ith fracture grid, Δ x _j Is the length of the jth fracture grid,. DELTA.y is the width of the grid, P _i Pressure at the center point of the ith fracture grid, P _j The pressure at the center point of the jth fracture grid, A represents the fracture grid contact area, and h represents Deltax _i 2 and Δ x _j The sum of/2. As shown in fig. 8, based on the established linear flow model of the fracture region, the fracture may be divided into the same number of fracture infinitesimals along with the matrix sub-region, and the diversion effect between the fracture infinitesimals is considered, based on which, a full-implicit finite volume form may be obtained:

the above crack difference equation is established, and a solving matrix equation set is established by adopting SS full-implicit type:

wherein the content of the first and second substances,

respectively representing compression coefficient items of oil and water, wherein the leftmost matrix in the matrix equation set can represent a coefficient matrix, the coefficient matrix can represent crack conduction coefficient, and X _i Denotes fracture pressure and saturation, q _i Flow rates in the injection zone and the production zone, b _i The residue term of the formula (23) after being converted into the formula (24) by a shift term has no actual physical meaning. In the above matrix equation system, each row may represent one-dimensional linear sub-region, and n may represent the total number of linear sub-regions.

Therefore, the oil-water flow rate q when injected into the zone _o,L And q is _w,L And the oil-water flow q of the production zone _o,R And q is _w,R After the determination, the fracture pressure P can be obtained by solving the linear flow model of the fracture area by using the formula _f Water saturation in fracture S _wF 。

Firstly, establishing an equal saturation surface equation of an injection end by using a corrected BL equation, and establishing a seepage resistance equation before and after crack water breakthrough so as to obtain a matrix flooding analytical solution; then, establishing a numerical solution of a fracture system by adopting a full-implicit finite volume method (CVF); solving seepage resistance equations before and after water breakthrough by establishing an outlet end isosaturation surface equation, thereby obtaining an outlet end matrix flooding analytical solution; and finally, coupling the flow of the injection area, the flow of the extraction area, the pressure of the crack and the water saturation, converting the two-dimensional problem of the water flooding reservoir oil into a one-dimensional linear sub-area coupling solving problem, and obtaining the linear flow half-analysis of the three areas of the water flooding reservoir oil. By analyzing and solving matrixes in an injection area and a production area, numerically solving is carried out on a fracture area by adopting a finite volume method, the advantages of the analytical solution and the numerical solution are used for reference, the fracture is dispersed into a plurality of nodes, and a semi-analytical solution under a dispersed fracture network is obtained by coupling the fracture, a shaft and a fluid flow equation.

And 110, simulating a saturation field and a pressure field of the reservoir stratum with the developed cracks to be treated according to the obtained crack pressure, the crack water saturation, the injection area pressure distribution, the injection area saturation distribution, the extraction area pressure distribution and the extraction area saturation distribution.

In a specific implementation process, fig. 9 is a schematic diagram of a solving flow of a trilinear flow model in an embodiment of this specification, and the meaning of each parameter in fig. 9 may refer to the description of the above embodiment, which is not repeated herein. As shown in fig. 9, fluid exchange exists among the injection area, the fracture area, and the production area, and only by coupling equations of the three areas, simulation of various indexes (oil displacement efficiency and water content) of water displacement and a seepage field (including a saturation field and a pressure field) of the whole area (the injection area, the fracture area, and the production area) can be obtained, so as to describe the distribution of remaining oil after water displacement of the fractured reservoir. As shown in fig. 9, the injection area and the extraction area may be solved first to obtain oil-water flow rates of the injection area and the extraction area, pressure distribution of the injection area, saturation distribution of the injection area, pressure distribution of the extraction area, and saturation distribution of the extraction area, and then the fracture area may be solved by using the oil-water flow rates of the injection area and the extraction area and using a fully implicit equation set to obtain fracture pressure and fracture water saturation. After the one-dimensional linear sub-regions are solved in sequence, the pressure and the saturation of any point in each linear sub-region can be obtained. Similarly, as shown in fig. 9, the iterative solution is continuously performed on each one-dimensional linear sub-region, and the pressure and saturation distribution at any point in each linear sub-region at any time can be obtained until the iteration number or the accuracy meets the preset condition, so as to obtain the pressure field and saturation distribution in the whole region at a certain time. Based on the same method, the pressure field and the saturation distribution in the whole area at the next moment can be obtained based on the pressure field and the saturation distribution obtained from the historical time along with the lapse of time, so that the simulation of the water flooding saturation field and the pressure field is realized, the residual saturation and the extraction degree distribution of the to-be-treated fracture development reservoir can be further obtained by combining the pressure, the saturation and the like, and the simulation of the water flooding process of the to-be-treated fracture development reservoir is realized.

The simulation method for water flooding of a fractured developmental reservoir provided in the embodiments of the present specification is to divide a matrix into a plurality of linear sub-regions based on water flooding displacement streamline characteristics of fractured cores with different shapes in a fractured reservoir, convert a two-dimensional problem of water flooding into a one-dimensional linear sub-region coupled solution problem, divide each linear sub-region into an injection region, a fracture region and a production region, respectively create corresponding linear flow models for flow characteristics of the injection region, the fracture region and the production region, sequentially solve each linear flow model, solve a linear displacement analytical solution of the matrix region at an injection end, a fracture linear diversion numerical solution, an outlet end matrix displacement analytical solution, couple matrix and fracture system linear flow, convert a two-dimensional problem of water flooding into a one-dimensional linear sub-region coupled solution, obtain a water flooding semi-analytical solution of a fractured core with fractures, and further obtain pressure distribution and saturation distribution of the fractured reservoir, the accurate simulation of the water flooding process of the crack development reservoir is realized.

In the present specification, each embodiment of the method is described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from other embodiments. The relevant points can be obtained by referring to the partial description of the method embodiment.

Based on the method for simulating water flooding of the fracture development reservoir, one or more embodiments of the present specification further provide a device for simulating water flooding of the fracture development reservoir. The apparatus may include systems (including distributed systems), software (applications), modules, components, servers, clients, etc. that employ the methods of the embodiments of the present description in conjunction with any necessary apparatus to implement the hardware. Based on the same innovative conception, the embodiments of the present specification provide an apparatus as in the following embodiments. Since the implementation scheme of the apparatus for solving the problem is similar to that of the method, the specific apparatus implementation in the embodiment of the present specification may refer to the implementation of the foregoing method, and repeated details are not repeated. As used hereinafter, the term "unit" or "module" may be a combination of software and/or hardware that implements a predetermined function. Although the systems, devices described in the embodiments below are preferably implemented in software, implementations in hardware, or a combination of software and hardware are also possible and contemplated.

Fig. 10 is a schematic structural diagram of a simulation apparatus for reservoir oil flooding of a fracture development reservoir in an embodiment of the present description, and as shown in fig. 10, the simulation apparatus for reservoir oil flooding of a fracture development reservoir provided in some embodiments of the present description may specifically include:

the sub-region dividing module 101 is configured to discretely divide a matrix in a dual medium model corresponding to a fracture development reservoir to be processed into a plurality of one-dimensional linear sub-regions according to fracture occurrence distribution in the fracture development reservoir to be processed, where each one-dimensional linear sub-region includes fracture microelements;

the linear flow model creating module 102 is configured to divide each one-dimensional linear sub-region into an injection region, a fracture region, and a production region, and respectively create a trilinear flow model corresponding to each one-dimensional linear sub-region according to flow characteristics corresponding to the injection region, the fracture region, and the production region, where the trilinear flow model includes: an injection zone linear flow model, a fracture zone linear flow model and a production zone linear flow model;

the oil-water flow calculation module 103 is used for sequentially solving the injection region linear flow model and the extraction region linear flow model in the trilinear flow model corresponding to each one-dimensional linear subregion to obtain the oil-water flow, the injection region pressure distribution, the injection region saturation distribution and the extraction region oil-water flow, the extraction region pressure distribution and the extraction region saturation distribution of the injection region corresponding to each one-dimensional linear subregion;

the pressure saturation solving module 104 is configured to sequentially solve a fracture area linear flow model in the trilinear flow model corresponding to each one-dimensional linear sub-area based on the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear sub-area, and obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear sub-area;

and the water drive simulation module 105 is used for simulating a saturation field and a pressure field of the to-be-treated fracture development reservoir according to the obtained fracture pressure, the fracture water saturation, the injection area pressure distribution, the injection area saturation distribution, the production area pressure distribution and the production area saturation distribution.

The simulation apparatus for water flooding of a fractured developmental reservoir provided in the embodiments of the present description divides a matrix into a plurality of linear sub-regions based on water flooding displacement streamline characteristics of fractured cores with different shapes in a fractured reservoir, converts a two-dimensional problem of water flooding into a one-dimensional linear sub-region coupled solution problem, divides each linear sub-region into an injection region, a fractured region and a production region, creates corresponding linear flow models respectively for flow characteristics of the injection region, the fractured region and the production region, sequentially solves each linear flow model, solves a linear displacement analytical solution of the matrix region at an injection end, a fracture linear diversion numerical solution, an outlet-end matrix displacement analytical solution, couples matrix and fracture system linear flow, converts a two-dimensional problem of water flooding into a one-dimensional linear sub-region coupled solution, obtains a water flooding semi-analytical solution of a fractured core with fractures, and further obtains pressure distribution and saturation distribution of the fractured reservoir, the accurate simulation of the water flooding process of the crack development reservoir is realized.

It should be noted that the above-mentioned apparatuses may also include other embodiments according to the description of the corresponding method embodiments. The specific implementation manner may refer to the description of the above corresponding method embodiment, and is not described in detail herein.

An embodiment of the present specification further provides a simulation apparatus for reservoir flooding of a fracture development reservoir, where the apparatus includes at least one processor and a memory for storing executable instructions of the processor, and the instructions, when executed by the processor, implement a simulation method for reservoir flooding of the fracture development reservoir, including:

sequentially solving a fracture area linear flow model in a trilinear flow model corresponding to each one-dimensional linear subregion based on the oil-water flow of the injection area and the oil-water flow of the extraction area corresponding to each one-dimensional linear subregion to obtain the fracture pressure and the fracture water saturation of the fracture area corresponding to each one-dimensional linear subregion;

and simulating a saturation field and a pressure field of the fracture development reservoir to be treated according to the obtained fracture pressure, the fracture water saturation, the injection area pressure distribution, the injection area saturation distribution, the extraction area pressure distribution and the extraction area saturation distribution.

It should be noted that the above description of the apparatus according to the method embodiment may also include other embodiments. The specific implementation manner may refer to the description of the related method embodiment, and details are not described herein.

The method or apparatus of the foregoing embodiments provided in this specification can implement service logic through a computer program and record the service logic on a storage medium, and the storage medium can be read and executed by a computer, so as to implement the effects of the solutions described in the embodiments of this specification.

The method embodiments provided by the embodiments of the present specification can be executed in a mobile terminal, a computer terminal, a server or a similar computing device. Taking an example of running on a server, fig. 11 is a hardware structure block diagram of a simulation server for water flooding of a fracture development reservoir in an embodiment of the present specification, and the computer terminal may be the simulation server for water flooding of the fracture development reservoir or a simulation processing device for water flooding of the fracture development reservoir in the above embodiment. The server 10 as shown in fig. 11 may include one or more (only one shown) processors 100 (the processors 100 may include, but are not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA, etc.), a non-volatile memory 200 for storing data, and a transmission module 300 for communication functions. It will be understood by those skilled in the art that the structure shown in fig. 11 is only an illustration and is not intended to limit the structure of the electronic device. For example, the server 10 may also include more or fewer components than shown in FIG. 11, and may also include other processing hardware, such as a database or multi-level cache, a GPU, or have a different configuration than shown in FIG. 11, for example.

The non-volatile memory 200 may be configured to store software programs and modules of application software, such as program instructions/modules corresponding to the taxi taking data processing method in the embodiment of the present specification, and the processor 100 executes various functional applications and resource data updates by running the software programs and modules stored in the non-volatile memory 200. Non-volatile memory 200 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the non-volatile memory 200 may further include memory located remotely from the processor 100, which may be connected to a computer terminal over a network. Examples of such networks include, but are not limited to, the internet, intranets, office-to-network, mobile communication networks, and combinations thereof.

The transmission module 300 is used for receiving or transmitting data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the computer terminal. In one example, the transmission module 300 includes a Network adapter (NIC) that can be connected to other Network devices through a base station so as to communicate with the internet. In one example, the transmission module 300 may be a Radio Frequency (RF) module, which is used for communicating with the internet in a wireless manner.

The foregoing description has been directed to specific embodiments of this disclosure. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may also be possible or may be advantageous.

The simulation method or apparatus for reservoir flooding for fracture development provided in the embodiments of this specification may be implemented in a computer by a processor executing corresponding program instructions, for example, implemented in a PC end using a c + + language of a windows operating system, implemented in a linux system, or implemented in an intelligent terminal using android and iOS system programming languages, implemented in processing logic based on a quantum computer, or the like.

All the embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the hardware + program class embodiment, since it is substantially similar to the method embodiment, the description is simple, and the relevant points can be referred to only the partial description of the method embodiment.

Although one or more embodiments of the present description provide method operational steps as in the embodiments or flowcharts, more or fewer operational steps may be included based on conventional or non-inventive approaches. The order of steps recited in the embodiments is merely one manner of performing the steps in a multitude of orders and does not represent the only order of execution. When the device or the end product in practice executes, it can execute sequentially or in parallel according to the method shown in the embodiment or the figures (for example, in the environment of parallel processors or multi-thread processing, even in the environment of distributed resource data update). The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the presence of additional identical or equivalent elements in a process, method, article, or apparatus that comprises an element is not excluded. The terms first, second, etc. are used to denote names, but not any particular order.

For convenience of description, the above devices are described as being divided into various modules by functions, and are described separately. Of course, when implementing one or more of the present description, the functions of each module may be implemented in one or more software and/or hardware, or a module implementing the same function may be implemented by a combination of multiple sub-modules or sub-units, etc. The above-described embodiments of the apparatus are merely illustrative, and for example, a division of a unit is merely a division of one logic function, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for system embodiments, since they are substantially similar to method embodiments, the description is relatively simple, and the relevant points can be referred to only part of the description of the method embodiments. In the description of the specification, reference to the description of "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the specification. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without being mutually inconsistent.

The above description is merely exemplary of one or more embodiments of the present disclosure and is not intended to limit the scope of one or more embodiments of the present disclosure. Various modifications and alterations to one or more embodiments described herein will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement or the like made within the spirit and principle of the present specification should be included in the scope of the claims.

Claims

1. A simulation method for water flooding of a fracture development reservoir is characterized by comprising the following steps:

dividing each one-dimensional linear sub-area into an injection area, a fracture area and a production area, and respectively establishing a trilinear flow model corresponding to each one-dimensional linear sub-area according to the flow characteristics corresponding to the injection area, the fracture area and the production area, wherein the trilinear flow model comprises the following steps: an injection region linear flow model, a fracture region linear flow model and a production region linear flow model;

2. The method of claim 1, wherein the establishing a trilinear flow model for each one-dimensional linear subregion based on the flow characteristics corresponding to the injection zone, the fracture zone, and the production zone, respectively, comprises:

initial conditions: p is a radical of formula _m | _t＝0 ＝p _i ,S _o | _t＝0 ＝S _oi

Inner boundary conditions:

outer boundary conditions:

wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear sub-regions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, q _w Water injection quantity, L, for a single one-dimensional linear subregion _L As the position of the crack, p _f Is the pressure of the fracture.

3. The method of claim 1, wherein the establishing a trilinear flow model for each one-dimensional linear subregion based on the flow characteristics corresponding to the injection zone, the fracture zone, and the production zone, respectively, comprises:

initial conditions:

inner boundary conditions:

outer boundary conditions:

wherein k is _f Absolute permeability of crack, k _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Is the oil phase viscosity, μ _w Is the viscosity of the aqueous phase,. epsilon.is the crack extension direction, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, q _o,L Amount of oil supplied to the injection zone per unit volume, q _o,R The amount of oil supplied to the production zone per unit volume is negative, q _w,L The amount of water supplied per unit volume of the injection zone, q _w,R The amount of water supplied to the production zone per unit volume is negative, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, p _f Pressure of the fracture, p _i Denotes the initial pressure, L _f The total length of the fracture is indicated, and the inner and outer boundaries of the fracture are closed boundaries.

4. The method of claim 1, wherein the establishing a trilinear flow model for each one-dimensional linear subregion based on the flow characteristics for the injection zone, the fracture zone, and the production zone, respectively, comprises:

initial conditions:

inner boundary conditions:

outer boundary conditions:

wherein k is _ro Relative permeability of the oil phase, k _rw Relative permeability of the aqueous phase, μ _o Viscosity of oil phase, μ _w Is the viscosity of the aqueous phase, x is the linear flow direction of the fluid, B _o Is the volume coefficient of crude oil, B _w Is the water volume coefficient, p _m As the pressure of the substrate, p _i Denotes the initial pressure, q _o,m Is the amount of oil per unit volume which has cross-flow between one-dimensional linear sub-regions, q _w,m Is the amount of cross-flow between one-dimensional linear sub-regions per unit volume, phi is the porosity, k _m Is the absolute permeability of the matrix, S _o Is the oil saturation, S _w Is the water saturation, t is the time, S _oi Is the original oil saturation, q _w Water injection quantity, L, for a single one-dimensional linear subregion _L As the position of the crack, p _w Is the outlet end pressure.

5. The method of claim 1, wherein solving for the injection zone linear flow model and the production zone linear flow model in the tri-linear flow model corresponding to each one-dimensional linear sub-region in sequence comprises:

6. The method of claim 1, wherein the sequentially solving the linear flow model of the fracture zone in the trilinear flow model corresponding to each one-dimensional linear subregion based on the oil-water flow of the injection zone and the oil-water flow of the production zone corresponding to each one-dimensional linear subregion comprises:

7. The method of claim 1, wherein the discretely dividing the matrix in the dual medium model corresponding to the fracture development reservoir to be processed into a plurality of one-dimensional linear subregions according to the fracture occurrence distribution in the fracture development reservoir to be processed comprises:

8. A simulation apparatus for water flooding of a fracture-developing reservoir, the apparatus comprising:

the fracture treatment device comprises a subarea dividing module, a fracture analysis module and a fracture analysis module, wherein the subarea dividing module is used for discretely dividing a matrix in a dual medium model corresponding to a fracture development reservoir to be treated into a plurality of one-dimensional linear subareas according to fracture occurrence distribution in the fracture development reservoir to be treated, and each one-dimensional linear subarea comprises fracture microelements;

the linear flow model creating module is used for dividing each one-dimensional linear sub-region into an injection region, a fracture region and a production region, and respectively establishing a trilinear flow model corresponding to each one-dimensional linear sub-region according to the flow characteristics corresponding to the injection region, the fracture region and the production region, wherein the trilinear flow model comprises: an injection region linear flow model, a fracture region linear flow model and a production region linear flow model;

9. A simulation apparatus for water flooding of a fracture-developing reservoir, the apparatus comprising at least one processor and a memory for storing processor-executable instructions which, when executed by the processor, implement steps comprising the method of any one of claims 1 to 7.

10. A computer program product comprising computer programs or instructions, characterized in that said computer programs or instructions, when executed by a processor, implement the steps of the method of any of the preceding claims 1-7.