CN109408859B - Method for establishing two-dimensional triple medium numerical model of shale gas reservoir fractured horizontal well - Google Patents
Method for establishing two-dimensional triple medium numerical model of shale gas reservoir fractured horizontal well Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 42
- 239000011159 matrix material Substances 0.000 claims abstract description 47
- 238000004519 manufacturing process Methods 0.000 claims abstract description 10
- 206010017076 Fracture Diseases 0.000 claims description 104
- 208000010392 Bone Fractures Diseases 0.000 claims description 84
- 230000035699 permeability Effects 0.000 claims description 22
- 238000012545 processing Methods 0.000 claims description 8
- 230000006835 compression Effects 0.000 claims description 5
- 238000007906 compression Methods 0.000 claims description 5
- 238000003795 desorption Methods 0.000 claims description 5
- 238000001179 sorption measurement Methods 0.000 claims description 5
- 230000005465 channeling Effects 0.000 claims description 4
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- GNFTZDOKVXKIBK-UHFFFAOYSA-N 3-(2-methoxyethoxy)benzohydrazide Chemical compound COCCOC1=CC=CC(C(=O)NN)=C1 GNFTZDOKVXKIBK-UHFFFAOYSA-N 0.000 claims description 2
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
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Abstract
The invention discloses a method for establishing a two-dimensional triple medium numerical model of a shale gas reservoir fracturing horizontal well, which relates to the field of petroleum and natural gas exploration and development, wherein a matrix system seepage difference equation, a natural fracture system seepage difference equation and a hydraulic main fracture seepage difference equation are respectively established, for three-diagonal and five-diagonal difference equations formed by artificial fractures, natural fractures and a matrix, a successive super-relaxation iteration method is adopted to convert the three-diagonal difference equations into three-diagonal difference equations, the pressure distribution of the artificial fractures and the natural fractures can be obtained by adopting a catch-up method, then the pressure distribution of the matrix is obtained, and the dynamic production prediction is carried out.
Description
Technical Field
The invention relates to the field of petroleum and natural gas exploration and development, in particular to a shale gas reservoir fracturing horizontal well two-dimensional triple medium numerical model building method based on an implicit finite difference method.
Background
At present, the research on the development of unconventional energy source gas such as shale gas at home and abroad enters a rapid development stage. Some experts and scholars develop a great deal of research on the aspects of shale gas reservoir formation mechanism, resource quantity evaluation, yield increase process and the like, and part of documents report the research on the seepage and yield decreasing rule of shale gas. However, because shale gas reservoir conditions are complex, most research results only give out shale gas seepage laws and influence factors thereof, no specific seepage model is proposed, and although some documents also propose specific seepage equations, the considered factors are not comprehensive enough, such as:
(1) establishing whether a shale gas bedrock flow equation considers micro flow characteristics such as viscous flow, knudsen diffusion, slip flow, gas adsorption and desorption and the like in a matrix;
(2) a multi-scale flowing space flowing from a matrix to a natural fracture and from the natural fracture to a fracturing fracture is formed after the shale gas reservoir is fractured, the natural fracture is a main seepage channel, and whether a natural fracture seepage mathematical model considers a gas viscous flow mechanism in the natural fracture or not is established.
(3) Whether the artificial main fracture seepage mathematical model corrects the Darcy law or not is considered, a correction coefficient of the Darcy flow is introduced, and the high-speed Darcy flow is described by a quadratic equation.
(4) Whether the continuity of flow between the natural fracture system and the artificial main fracture, the balance of pressure and the convenience of calculation are considered in the solving method of the model; whether the influence of the yield of the shale gas reservoir volume fractured horizontal well on the volume fracture control area can be really represented or not.
Disclosure of Invention
The invention aims to overcome the defects and shortcomings of the prior art, and provides a method for establishing a two-dimensional triple medium numerical model of a shale gas reservoir fractured horizontal well.
The invention is realized by adopting the following technical scheme:
a shale gas reservoir fractured horizontal well two-dimensional triple medium numerical model building method is characterized by comprising the following steps:
a. substituting the adsorption and desorption terms into a matrix differential equation for derivation, introducing a total compression coefficient, a matrix and natural fracture channeling terms, and obtaining a matrix system seepage differential equation by adopting five-point finite difference approximation:
wherein:
A x ＝△yh,A y ＝△xh,V b ＝△x△yh
in the formula:
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t — time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y-the size of the grid where the crack is located, m;
K app -apparent permeability, mD;
ρg gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
C mt -the overall compressibility of the matrix system;
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
p f -the natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
h-thickness of gas reservoir, m.
b. The natural fractured shale reservoir is simplified into a dual continuous medium model, a matrix and natural fractures are two parallel hydrodynamic fields, a two-dimensional continuity equation of a natural fracture system is obtained according to a continuous medium theory, and a five-point finite difference approximation is adopted to obtain a seepage difference equation of the natural fracture system:
wherein:
in the formula:
φ f natural fracture porosity, dimensionless;
K f -fracture permeability, mD;
C ft -natural fracture system integrated compressibility;
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t — time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y, delta z-the size of the grid where the crack is located, m;
K app -apparent permeability, mD;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
p f -natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -the artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
c. the shale volume fracturing reconstruction area is composed of a main crack and a secondary crack network, the artificial main crack is still a double-wing symmetrical crack vertical to a shaft, the artificial main crack is a main channel for communicating a natural crack and the shaft, the width of the crack is narrow, so that the flow in the width direction of the main crack is not considered, the fluid in the main crack flows in a plane one-dimensional mode, a continuity equation of the artificial main crack in a one-dimensional mode is obtained, and a three-point finite difference approximation is adopted to obtain a seepage difference equation of the hydraulic main crack:
wherein
A Fz ＝W F △y,V Fb ＝W F △yh
In the formula:
C Ft -comprehensive compressibility factor of artificial fracture system, MPa -1 ；
W F -crack width, m;
φ F artificial fracture porosity, dimensionless;
q well -flow rate of artificial fracture and well bore in kg/(dm) 3 )；
K f -fracture permeability, mD;
C ft -natural fracture system integrated compressibility;
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y, delta z-the size of the grid where the crack is located, m;
ρ g gas density, kg/m 3 ；
μ g -gasViscosity, mPa · s;
p f -the natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
h-thickness of gas reservoir, m.
A Fz -representing the cross-sectional area of the grid of the artificial fracture in the z-direction, m 2 ；
V Fb -artificial fracture grid volume, m 3 ；
d. Jointly solving three equations in the steps a, b and c; and for the three-diagonal and five-diagonal differential equations, a successive super-relaxation iteration method is adopted to convert the three-diagonal and five-diagonal differential equations into the three-diagonal differential equations, the pressure distribution of the artificial fractures and the natural fractures can be obtained by adopting a catch-up method, and then the pressure distribution of the matrix is obtained to perform dynamic production prediction.
And e, processing the artificial main cracks into discrete large cracks, processing the natural cracks and induced secondary cracks formed by volume fracturing into continuous medium bodies, dividing the main cracks and the gas reservoir by adopting a uniform grid system, and dividing the matrix and the grids of the cracks by adopting a non-uniform grid system and a local encryption method.
F, virtualizing a row of grids outside the gas reservoir boundary grid, and taking the pressure of the grids as initial pressure for the constant-pressure outer boundary on the assumption that the absolute permeability of the stratum is equal to that of the adjacent gas reservoir grids; the pressure of the cells is taken to be equal for the closed outer boundary.
The method further comprises a step g of obtaining the permeability K of the anisotropic gas reservoir by rotating the coordinate axis of the Peacheman vertical well processing model:
the converted radius of the well block grid is as follows:
in the formula:
r e -equivalent radius of well grid block, m;
K x 、K y 、K z -permeability in X, Y, Z direction, D;
Δ y, Δ z-the size of the grid where the crack is located, m.
For isotropic gas reservoirs, the converted radius of the well block grid is:
in the formula:
r e -equivalent radius of well grid block, m;
Δ y, Δ z-the size of the grid where the crack is located, m.
And h, programming or programming software on a Matlab software platform for solving, collecting mine field data and basic parameters related to a single well, and operating a solving program for fitting.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the method, the two-dimensional triple medium numerical model of the shale gas reservoir fracturing horizontal well based on the implicit finite difference method is established, and the inaccuracy of results caused by the incomplete consideration factors of the establishment of the seepage model is avoided to a certain extent, so that more reliable technical guarantees are provided for the yield evaluation, fracturing process improvement and the like of the shale gas well on the mine site after fracturing.
2. Three united solving methods of a matrix, a natural fracture and a hydraulic main fracture system seepage differential equation are innovated, for three diagonal differential equations and five diagonal differential equations, a successive super-relaxation iteration method is adopted, and the three diagonal differential equations are converted into three diagonal differential equations, so that a two-dimensional problem is reduced to a one-dimensional problem, the pressure distribution of an artificial fracture and the natural fracture can be solved by adopting a catch-up method, and then the pressure distribution of the matrix is solved.
3. In matrix and fracture treatment, the influence of a yield receptor on a volume fracturing control area of a volume fracturing horizontal well is well characterized in order to meet the continuity of flow between a natural fracture system and an artificial main fracture, the balance of pressure and the convenience of calculation. Treating the artificial main cracks into discrete large cracks, and treating the natural cracks and induced secondary cracks formed by volume fracturing into continuous medium bodies; and dividing the main cracks and the gas reservoir by adopting a uniform grid system, and dividing the grids of the matrix and the cracks by adopting a non-uniform grid system and a local encryption method.
4. The method has breakthrough in the division of a fracturing reservoir grid system, the condition of the outer boundary and the well processing technology. And virtualizing a row of grids outside the boundary grid of the gas reservoir, and assuming that the absolute permeability of the stratum is equal to that of the adjacent gas reservoir grids. Taking the pressure of the grid as the initial pressure variation zero for the constant-pressure outer boundary; the pressure of the cells is taken to be equal for the closed outer boundary.
5. The invention relates to a shale gas reservoir fractured horizontal well two-dimensional triple medium numerical model based on an implicit finite difference method, which belongs to innovation of a shale gas seepage mechanism research application method.
6. The invention has wide application range and can be effectively applied to the seepage mechanism research and application of shale gas wells at home and abroad and the corresponding numerical simulation technology research.
Drawings
The invention will be described in further detail with reference to the following description taken in conjunction with the accompanying drawings and detailed description, in which:
FIG. 1 is a simulation verification diagram of shale field data;
FIG. 2 is a graph of historical production data fit results for a well according to the present invention.
Detailed Description
Example 1
The invention discloses a two-dimensional triple medium numerical model building method for a shale gas reservoir fractured horizontal well, which is a better implementation mode and is characterized by comprising the following steps of:
a. substituting the adsorption and desorption terms into a matrix differential equation for derivation, introducing a total compression coefficient, a matrix and natural fracture channeling terms, and obtaining a matrix system seepage differential equation by adopting five-point finite difference approximation:
wherein:
A x ＝△yh,A y ＝△xh,V b ＝△x△yh
in the formula:
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y-the grid size, m, where the crack is located;
K app apparent penetrationRate, mD;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
C mt -the overall compressibility of the matrix system;
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
p f -the natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
h is the gas reservoir thickness, m.
b. The natural fractured shale reservoir is simplified into a dual continuous medium model, a matrix and a natural fracture are two parallel hydrodynamic fields, a two-dimensional continuity equation of a natural fracture system is obtained according to a continuous medium theory, and a five-point finite difference approximation is adopted to obtain a seepage difference equation of the natural fracture system:
wherein:
in the formula:
φ f natural fracture porosity, dimensionless;
K f -fracture permeability, mD;
C ft -natural fracture system integrated compressibility;
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y, delta z-the size of the grid where the crack is located, m;
K app -apparent permeability, mD;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
p f -the natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
c. the shale volume fracturing reconstruction area is composed of a main crack and a secondary crack network, the artificial main crack is still a double-wing symmetrical crack vertical to a shaft, the artificial main crack is a main channel for communicating a natural crack and the shaft, because the width of the crack is very narrow, the flowing in the width direction of the main crack is not considered, the fluid in the main crack is in planar one-dimensional flowing, a continuity equation of the artificial main crack in a one-dimensional form is obtained, and a three-point finite difference approximation is adopted to obtain a seepage difference equation of the hydraulic main crack:
wherein
A Fz ＝W F △y,V Fb ＝W F △yh
In the formula:
C Ft -comprehensive compressibility of artificial fracture system, MPa -1 ；
W F -crack width, m;
φ F artificial fracture porosity, dimensionless;
q well -flow rate of artificial fracture and well bore in kg/(dm) 3 )；
K f -fracture permeability, mD;
C ft -natural fracture system composite compressibility;
A x ,A y -representing the cross-sectional area of the grid in the x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Delta x, delta y, delta z-the size of the grid where the crack is located, m;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
p f -the natural fracture block pressure, MPa, of the grid in which the natural fractures are located;
P F -the artificial fracture block pressure, MPa, of the grid in which the artificial fractures are located;
h-thickness of gas reservoir, m.
A Fz -representing the cross-sectional area of the grid of the artificial fracture in the z-direction, m 2 ；
V Fb -artificial fracture grid volume, m 3 ；
d. Jointly solving three equations in the steps a, b and c; and for the three-diagonal and five-diagonal differential equations, a successive super-relaxation iteration method is adopted to convert the three-diagonal and five-diagonal differential equations into the three-diagonal differential equations, the pressure distribution of the artificial fractures and the natural fractures can be obtained by adopting a catch-up method, and then the pressure distribution of the matrix is obtained to perform dynamic production prediction.
Example 2
As the best implementation mode of the invention, the invention discloses a two-dimensional triple medium numerical model of a shale gas reservoir fractured horizontal well, which is characterized by comprising the following steps of:
(1) substituting the adsorption and desorption terms into a matrix differential equation for derivation, introducing a total compression coefficient, a matrix and natural fracture channeling terms, and obtaining a matrix system seepage differential equation by adopting five-point finite difference approximation;
(2) according to the continuous medium theory, obtaining a two-dimensional continuity equation of the natural fracture system, and then obtaining a seepage difference equation of the natural fracture system by adopting five-point finite difference approximation;
(3) and (3) the flow in the width direction of the main crack is not considered, the fluid in the main crack flows in a planar one-dimensional mode, a continuity equation of a one-dimensional form of the artificial main crack is obtained, and then a three-point finite difference approximation is adopted to obtain a water pressure main crack seepage difference equation.
(4) The three equations are jointly solved, a successive super-relaxation iteration method is adopted, the three equations are converted into a three-diagonal differential equation, the two-dimensional problem is reduced to a one-dimensional problem, the pressure distribution of the artificial cracks and the natural cracks can be obtained by a catch-up method, then the pressure distribution of the matrix is obtained, and the dynamic production prediction is carried out.
(5) The artificial main cracks are processed into discrete large cracks, and the natural cracks and the induced secondary cracks formed by volume fracturing are processed into continuous medium bodies. The uniform grid system is adopted to divide the main cracks and the gas reservoir, and the non-uniform grid system and the local encryption method are adopted to divide the grids of the matrix and the cracks.
(6) And virtualizing a row of grids outside the boundary grid of the gas reservoir, and assuming that the absolute permeability of the stratum is equal to that of the adjacent gas reservoir grids. Taking the pressure of the grid as initial pressure for the constant-pressure outer boundary; the pressure of the cells is taken to be equal for the closed outer boundary.
(7) The horizontal well is obtained by rotating the coordinate axis of the Peacheman vertical well processing model, and for the anisotropic gas reservoir, the permeability adopts the geometric mean permeability. And respectively adopting different conversion formulas to determine the radiuses of the grids of the isotropic gas reservoir block and the anisotropic gas reservoir block.
(8) Programming or programming software on a Matlab software platform to solve, collecting mine field data and basic parameters related to a single well, and operating a solving program to perform fitting.
As can be seen from fig. 1, the calculation result is relatively consistent with the simulation result of Grieser and the actual Barnett shale mineral data, so that the correctness of the compiled production dynamic simulation program can be proved; as can be seen from FIG. 2, the production dynamic simulation result is close to the mineral production dynamic result, which proves the reliability of the established shale gas production dynamic simulation method.
Basic parameter table that table shale gas well numerical simulation needs to be collected
| Analog unit length/width (m) | Horizontal well shaft length (m) |
| Gas reservoir thickness (m) | Radius of wellbore (m) |
| Effective permeability of matrix (mD) | Effective porosity (%) |
| Initial pressure of stratum (MPa) | Bottom hole flowing pressure (MPa) |
| Formation temperature (K) | Compression coefficient of rock (MPa) -1 ) |
| Langmuir volume (m) 3 /t) | Langmuir pressure (MPa) |
| Effective porosity in artificial crack (%) | Number of fracturing stages |
| Flow conductivity of artificial crack (D cm) | Natural fracture porosity (%) |
| Gap net width (m) | Seam Net Length (m) |
| Tortuosity of pore space | Natural crack permeability (mD) |
| Natural crack spacing (m) | Fracture compressibility factor (MP)a -1 ) |
| SRV zone Permeability (mD) | Natural fracture stress sensitivity coefficient (MPa) -1 ) |
| Initial viscosity of natural gas (mPa.s) | Molecular weight of Natural gas (g/mol) |
| Deviation factor | Shale density (Kg/m) 3 ) |
Claims (5)
1. A method for establishing a two-dimensional triple medium numerical model of a shale gas reservoir fractured horizontal well is characterized by comprising the following steps of:
a. substituting the adsorption and desorption terms into a matrix differential equation for derivation, introducing a total compression coefficient, a matrix and natural fracture channeling terms, and obtaining a matrix system seepage differential equation by adopting five-point finite difference approximation:
wherein:
A x ＝Δyh,A y ＝Δxh,V b ＝ΔxΔyh
in the formula:
A x ,A y -representing the cross-sectional area of the grid in the x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Δ x, Δ y — the size of the grid where the fracture is located, m;
K app -apparent permeability, mD;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
C mt -the overall compressibility of the matrix system;
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
h-gas reservoir thickness, m;
b. the natural fractured shale reservoir is simplified into a dual continuous medium model, a matrix and natural fractures are two parallel hydrodynamic fields, a two-dimensional continuity equation of a natural fracture system is obtained according to a continuous medium theory, and a five-point finite difference approximation is adopted to obtain a seepage difference equation of the natural fracture system:
wherein:
in the formula:
φ f natural fracture porosity, dimensionless;
K f -fracture permeability, mD;
C ft -natural fracture system integrated compressibility;
A x ,A y -representing the cross-sectional area of the grid in the x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Δ x, Δ y, Δ z-the size of the grid where the fracture is located, m;
K app -apparent permeability, mD;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
σ -denotes the shape factor, m -2 ；
P m -matrix mass pressure, MPa, of the grid in which the matrix is located;
c. the shale volume fracturing reconstruction area is composed of a main fracture and a secondary fracture network, fluid in the main fracture flows in a plane one-dimensional mode without considering the flow in the width direction of the main fracture, a continuity equation of a one-dimensional form of an artificial main fracture is obtained, and a water pressure main fracture seepage difference equation is obtained by three-point finite difference approximation:
wherein
A Fz ＝W F Δy,V Fb ＝W F Δyh
In the formula:
C Ft -comprehensive compressibility of artificial fracture system, MPa -1 ；
W F -crack width, m;
φ F artificial fracture porosity, dimensionless;
q well -flow rate of artificial fracture and well bore, kg/(dm) 3 )；
K f -fracture permeability, mD;
C ft -natural fracture system composite compressibility;
A x ,A y -representing the cross-sectional area of the grid in x, y directions, respectively, m 2 ；
Δ t-time step, d;
V b -grid block volume, m 3 ；
Δ x, Δ y, Δ z-the size of the grid where the fracture is located, m;
ρ g gas density, kg/m 3 ；
μ g -gas viscosity, mPa · s;
h-gas reservoir thickness, m;
A Fz -representing the cross-sectional area of the grid of the artificial fracture in the z-direction, m 2 ；
V Fb -artificial fracture grid volume, m 3 ；
d. Jointly solving three equations in the steps a, b and c; and for the three-diagonal and five-diagonal differential equations, a successive super-relaxation iteration method is adopted to convert the three-diagonal differential equations into the three-diagonal differential equations, the pressure distribution of the artificial fractures and the natural fractures is obtained by a catch-up method, and then the pressure distribution of the matrix is obtained to perform dynamic production prediction.
2. The method for establishing the two-dimensional ternary medium numerical model of the shale gas reservoir fractured horizontal well according to claim 1 is characterized by comprising the following steps of: and e, processing the artificial main cracks into discrete large cracks, processing the natural cracks and induced secondary cracks formed by volume fracturing into continuous medium bodies, dividing the main cracks and the gas reservoir by adopting a uniform grid system, and dividing the matrix and the grids of the cracks by adopting a non-uniform grid system and a local encryption method.
3. The method for establishing the two-dimensional ternary medium numerical model of the shale gas reservoir fractured horizontal well according to claim 2 is characterized by comprising the following steps of: f, virtualizing a row of grids outside the gas reservoir boundary grid, and taking the pressure of the grids as initial pressure for a constant-pressure outer boundary on the assumption that the absolute permeability of a stratum is equal to that of an adjacent gas reservoir grid; the pressure of the cells is taken to be equal for the closed outer boundary.
4. The method for establishing the two-dimensional triple medium numerical model of the shale gas reservoir fractured horizontal well according to claim 3, wherein the method comprises the following steps: the method further comprises a step g of obtaining the permeability K of the anisotropic gas reservoir by rotating the coordinate axis of the Peacheman vertical well processing model:
the converted radius of the well block grid is as follows:
for isotropic gas reservoirs, the converted radius of the well block grid is:
in the formula:
r e -equivalent radius of well grid block, m;
K x 、K y 、K z -permeability in X, Y, Z direction, D;
dy, dz-the grid size where the cracks are located, m.
5. The method for establishing the two-dimensional ternary medium numerical model of the shale gas reservoir fractured horizontal well according to claim 4 is characterized by comprising the following steps of: and h, programming or programming software on a Matlab software platform for solving, collecting mine field data and basic parameters related to a single well, and operating a solving program for fitting.
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| CN110863810B (en) * | 2019-11-21 | 2020-08-18 | 西南石油大学 | Integrated simulation method for coupling shale gas reservoir hydraulic fracturing flowback production process |
| CN111062165B (en) * | 2019-12-16 | 2022-08-23 | 中国石油大学(华东) | Embedded discrete fracture simulation method and system considering nonlinear flow |
| CN111125905B (en) * | 2019-12-20 | 2023-06-23 | 重庆科技学院 | Two-dimensional fracture network expansion model for coupling oil reservoir fluid flow and simulation method thereof |
| CN111680445B (en) * | 2020-06-16 | 2022-02-18 | 西南石油大学 | Numerical simulation method for coal bed gas-dense gas combined mining |
| CN111577236B (en) * | 2020-07-03 | 2022-03-22 | 西南石油大学 | Multi-section fracturing seepage simulation device for compact oil reservoir horizontal well |
| CN111963163B (en) * | 2020-09-16 | 2021-07-27 | 西南石油大学 | Shale gas reservoir double-hole and double-permeation model construction and pressure dynamic prediction method based on gas-water two-phase flow |
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