High-temperature and high-pressure gas well shaft sand scale migration numerical simulation method and related equipment

Abstract

The invention discloses a high-temperature and high-pressure gas well shaft sand scale migration numerical simulation method and related equipment, which are based on a geometric function, considers the temperature and pressure influence effect, establishes a fluid flow pattern and particle tracking coupling model, and finely simulates the dynamic characteristic that sand scale migrates along with the output of fluid. Separating group error estimation and separating residual error estimation are carried out on the iteration fitting index, then time iteration is carried out, an output signal range is set, when an iteration value reaches the output signal range, a signal is output, sand scale migration and blockage in a shaft are explained according to the output signal, and the sand scale migration and blockage in the shaft are explained. The method is beneficial for quickly and accurately researching the influence condition of each blockage influence factor on sand scale migration, provides a targeted more scientific and more efficient suggestion measure for prevention and treatment of sand scale blockage of a shaft, can simulate the migration form of sand scale along with produced oil and gas and the dynamic blockage characteristic of sand scale adhered and deposited on a pipe wall in a high-temperature and high-pressure shaft environment, and has a good application prospect. Therefore, the sand scale migration rule is researched.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas reservoir development, and specifically relates to a high-temperature and high-pressure gas wellbore sand and scale migration numerical simulation method and related equipment. Background Art

[0002] In the process of exploiting tight sandstone oil and gas, wellbores often experience varying degrees of blockage, affecting the normal production of oil and gas. Among them, these blockages in the wellbores mainly come from the formation sand and formation scale carried into the wellbores by the oil and gas seeping from the formation, and some wellbores scale formed in the wellbores during the long-term exploitation and production process. These sands and scales will show different migration characteristics as the oil and gas migrate in the wellbores. When the sand and scale are in a suspended or settled state for a long time, they are easy to deposit and adhere to the wellbores wall, which is the cause of the sand and scale blocking the wellbores.

[0003] However, since the migration process of sand and scale in the wellbore is difficult to characterize precisely, and the high temperature and high pressure environment in which the migration occurs has a significant impact on the sand and scale migration characteristics, the existing technology makes it difficult to study the wellbore migration state and the regular characteristics of sand and scale migration under high temperature and high pressure environments. Summary of the invention

[0004] The present invention provides a method and related equipment for numerical simulation of sand and scale migration in a high-temperature and high-pressure gas wellbore, which solves the problem that it is difficult to study the wellbore migration state and the characteristics of sand and scale migration laws under a high-temperature and high-pressure environment in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas well, comprising:

[0007] Establish geometric model, fluid flow field and sand scale particle tracking field according to basic geo-engineering parameters;

[0008] Construct a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand scale particle tracking field;

[0009] Obtain iterative fitting index based on the fluid flow pattern and particle tracking coupling model;

[0010] Separate group error estimates and separate residual estimates for iterative fit indices, then run long iterations;

[0011] The output signal range is set. When the iteration value reaches the output signal range, the signal is output, and the blockage of sand and scale migration in the wellbore is interpreted based on the output signal.

[0012] Preferably, the basic geological engineering parameters include pipe string structure, bottom hole fluid temperature, bottom hole flow pressure, gas production, oil production, and geothermal gradient.

[0013] Preferably, the geometric model is obtained by converting the pipe string parameters into linear Lagrangian units and quadratic Lagrangian units, and establishing the geometric model according to the linear Lagrangian units and quadratic Lagrangian units.

[0014] Preferably, the iterative fitting indexes include a pressure index, a velocity field index, a turbulent kinetic energy index and a specific loss rate index.

[0015] Preferably, the iterative fitting index is obtained according to the fluid flow pattern and particle tracking coupling model as follows:

[0016] Based on the fluid flow pattern and particle tracking coupling model, the gas production, oil production and pressure parameters in the basic geological engineering parameters are established as an asymmetric matrix of multi-factor dependent variables of fluid velocity and pressure dynamic changes using the orthogonal null space function, and the pressure and velocity field indices are scaled to obtain them. Then, based on the orthogonal null space function, an asymmetric matrix of turbulence variables is established, which is scaled to form the turbulent kinetic energy and specific loss rate indices.

[0017] Preferably, the operation time iteration is specifically as follows: dividing the fluid-solid transport time into n steps, approximating the separation group error estimate and the separation group residual estimate at each time step, and constructing a pseudo time step CFL ratio at each step.

[0018] Preferably, the blockage of sand and scale migration in the wellbore is explained according to the output signal as follows:

[0019] The pseudo-time step CFL ratio of each iteration is calculated, and the n-th pseudo-time step CFL ratio is used as the actual adaptive control output signal. The actual adaptive control output signal is used to characterize the characteristics of the migration of sand and scale particles as the fluid flows in the wellbore, and the variables of the influencing factors are controlled. The trend of the influence of the changes in various factors on the wellbore blockage is studied, so as to explain the blockage of sand and scale migration in the wellbore.

[0020] A numerical simulation system for sand and scale migration in a high-temperature and high-pressure gas wellbore, comprising:

[0021] Establishment module: used to establish geometric model, fluid flow field and sand scale particle tracking field according to basic geological engineering parameters;

[0022] Model building module: used to build a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand and scale particle tracking field;

[0023] Index acquisition module: used to obtain iterative fitting index according to the fluid flow pattern and particle tracking coupling model;

[0024] Iteration module: separates group error estimates and separates residual estimates for iterative fit indices, and then runs long iterations;

[0025] Output module: Set the output signal range. When the iteration value reaches the output signal range, output the signal and interpret the sand and scale migration blockage in the wellbore according to the output signal.

[0026] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the numerical simulation method for sand and scale migration in the high-temperature and high-pressure gas wellbore are implemented.

[0027] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of the numerical simulation method for sand and scale migration in the high-temperature and high-pressure gas wellbore are implemented.

[0028] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas wellbore and related equipment. Based on the geometric shape function and considering the temperature and pressure influence effects, a coupled model of fluid flow pattern and particle tracking is established to finely simulate the dynamic characteristics of sand and scale migration with the production of fluid. Then, through the separation group error estimation and separation residual estimation of the iterative fitting index, and then running the duration iteration, setting the output signal range. When the iteration value reaches the output signal range, output the signal and interpret the sand and scale migration blockage in the wellbore according to the output signal, which helps to quickly and accurately study the influence of various blockage factors on sand and scale migration, and put forward more scientific and efficient opinion measures for the prevention and control of sand and scale blockage in the wellbore. It can simulate the migration form of sand and scale with the produced oil and gas and the dynamic blockage characteristics of adhesion and deposition on the pipe wall in the high-temperature and high-pressure wellbore environment, so as to study the sand and scale migration law. Description of the Drawings

[0029] Figure 1 It is the flowchart of the method in the embodiment of the present invention;

[0030] Figure 2 It is the variable-diameter flow velocity field distribution of the fluid in the wellbore of the present invention;

[0031] Figure 3 It is the variable-diameter pressure field distribution in the wellbore of the present invention;

[0032] Figure 4 It is the initial migration position distribution of sand and scale of the present invention;

[0033] Figure 5 It is the particle position distribution of sand and scale migration for 2 seconds of the present invention;

[0034] Figure 6 It is the particle position distribution of sand and scale migration for 5 seconds of the present invention;

[0035] Figure 7This is a flow chart of a numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas wellbore of the present invention;

[0036] Figure 8 This is a block diagram of a numerical simulation system for sand and scale migration in a high-temperature and high-pressure gas wellbore according to the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0040] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0041] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0042] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0044] like Figure 7 As shown, the present invention provides a method for numerical simulation of sand and scale migration in a high-temperature and high-pressure gas wellbore, comprising:

[0045] S101 establishes geometric models, fluid flow fields and sand and scale particle tracking fields based on basic geological engineering parameters;

[0046] S102 constructs a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand scale particle tracking field;

[0047] S103 obtains an iterative fitting index according to a fluid flow pattern and a particle tracking coupling model;

[0048] S104 performs separation group error estimation and separation residual estimation on the iterative fitting index, and then runs long-term iteration;

[0049] S105 sets the output signal range. When the iteration value reaches the output signal range, a signal is output, and the blockage of sand and scale migration in the wellbore is interpreted according to the output signal.

[0050] The basic geological engineering parameters include tubing structure, bottom hole fluid temperature, bottom hole flowing pressure, gas production, oil production, and geothermal gradient. The geometric model is obtained by converting the tubing parameters into linear Lagrangian units and quadratic Lagrangian units, and establishing a geometric model based on the linear Lagrangian units and quadratic Lagrangian units. The iterative fitting indexes include pressure index, velocity field index, turbulent kinetic energy index, and specific loss rate index.

[0051] The iterative fitting index obtained according to the fluid flow pattern and particle tracking coupling model is as follows:

[0052] Based on the fluid flow pattern and particle tracking coupling model, the gas production, oil production and pressure parameters in the basic geological engineering parameters are established as an asymmetric matrix of multi-factor dependent variables of fluid velocity and pressure dynamic changes using the orthogonal null space function, and the pressure and velocity field indices are scaled to obtain them. Then, based on the orthogonal null space function, an asymmetric matrix of turbulence variables is established, which is scaled to form the turbulent kinetic energy and specific loss rate indices.

[0053] The specific operation time iteration is as follows: the fluid-solid transport time is divided into n steps, the separation group error estimate and the separation group residual estimate at each time step are approximated, and the pseudo time step CFL ratio at each step is constructed.

[0054] The explanation of the blockage of sand and scale migration in the wellbore based on the output signal is as follows:

[0055] The pseudo-time step CFL ratio of each iteration is calculated, and the n-th pseudo-time step CFL ratio is used as the actual adaptive control output signal. The actual adaptive control output signal is used to characterize the characteristics of the migration of sand and scale particles as the fluid flows in the wellbore, and the variables of the influencing factors are controlled. The trend of the influence of the changes in various factors on the wellbore blockage is studied, so as to explain the blockage of sand and scale migration in the wellbore.

[0056] Example:

[0057] (1) Obtaining geological engineering simulation parameters

[0058] The basic geological engineering parameters obtained include pipe string structure, bottom hole fluid temperature, bottom hole flow pressure, gas production, oil production, geothermal gradient and other specific parameters, as shown in Table 1 below.

[0059] Table 1 Basic parameters

[0060]

[0061] (2) Establishing geometric model

[0062] Based on the geometric shape function, the pipe diameter parameters obtained in (1) are converted into linear Lagrangian elements and quadratic Lagrangian elements to establish a geometric model.

[0063] (3) Establish a coupling model of fluid flow pattern and particle tracking.

[0064] Based on the geometric model in (2), an additional fluid flow field is added to simulate the fluid flow state in the wellbore, and an additional particle tracking field is added to simulate the real-time state of sand and scale migration in the wellbore. A fluid flow pattern and particle tracking coupling model is established.

[0065] (4) Obtaining iterative fitting index

[0066] Based on the fluid flow pattern and particle tracking coupling model in (3), the gas production, oil production and pressure parameters in (1) are established as an asymmetric matrix of multi-factor dependent variables of fluid velocity and pressure dynamic changes using the orthogonal null space function, and the pressure and velocity field indices are obtained by scaling. Based on the orthogonal null space function, an asymmetric matrix of turbulence variables is established, which is scaled to form the turbulent kinetic energy and specific loss rate indices.

[0067] (5) Model iteration step division

[0068] Based on the separator solution control, the fluid-solid transport time is divided into n steps, the separation group error estimate and the separation group residual estimate at each time step are approximated, and the pseudo time step CFL ratio at each step is constructed.

[0069] (6) Iteration output signal

[0070] Iterate sequentially, calculate the CFL ratio of each pseudo-time step, take the CFL ratio of the nth pseudo-time step as the actual adaptive control output signal, and use the actual adaptive control output signal to characterize the characteristics of the migration of scale particles as the fluid flows in the wellbore. By accumulating the number of scale particles on the pipe wall, control the variables separately, and study the influence of production speed and scale particle size on scale migration and blockage. The distribution of the variable diameter velocity field of the fluid in the wellbore is shown in the attached figure. Figure 2 The pressure field distribution of the variable diameter in the wellbore is shown in the attached figure. Figure 3 The initial migration position of sand and scale is shown in the attached figure. Figure 4 As shown in the figure, the particle position distribution of sand scale migration for 2 seconds is shown in the attached figure. Figure 5 The particle position distribution of sand scale migration for 5 seconds is shown in the attached figure. Figure 6 As shown, it is found that near the wellbore diameter change, the fluid flow rate is significantly reduced, forming a low-pressure area, which makes it easy for sand and scale to deposit near the wellbore diameter change. When the production speed is smaller, the sand and scale particle size is larger, and the number of sand and scale particles deposited on the pipe wall is more, it means that the wellbore is more likely to be blocked.

[0071] like Figure 8 As shown, the present invention also provides a high-temperature and high-pressure gas wellbore sand and scale migration numerical simulation system, comprising:

[0072] Establishment module: used to establish geometric model, fluid flow field and sand scale particle tracking field according to basic geological engineering parameters;

[0073] Model building module: used to build a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand and scale particle tracking field;

[0074] Index acquisition module: used to obtain iterative fitting index according to the fluid flow pattern and particle tracking coupling model;

[0075] Iteration module: separates group error estimates and separates residual estimates for iterative fit indices, and then runs long iterations;

[0076] Output module: Set the output signal range. When the iteration value reaches the output signal range, output the signal. Based on the output signal, interpret the blockage of sand and scale migration in the wellbore.

[0077] A terminal device is provided in one embodiment of the present invention. The terminal device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of the modules / units in the above-mentioned device embodiments are implemented.

[0078] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to accomplish the present invention.

[0079] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0080] The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0081] The memory may be used to store the computer programs and / or modules, and the processor implements various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0082] If the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0083] Although the embodiments of the present invention are described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields, and the above-mentioned specific embodiments are only illustrative and instructive, rather than restrictive. Under the guidance of the specification, a person skilled in the art can also make many forms without departing from the scope of protection of the claims of the present invention, all of which belong to the scope of protection of the present invention.

Claims

1. A numerical simulation method for sand and scale migration in high-temperature and high-pressure gas wells. It is characterized in that include: Establish geometric model, fluid flow field and sand scale particle tracking field according to basic geo-engineering parameters; Construct a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand scale particle tracking field; Obtain iterative fitting index based on the fluid flow pattern and particle tracking coupling model; Separate group error estimates and separate residual estimates for iterative fit indices, then run long iterations; The output signal range is set. When the iteration value reaches the output signal range, the signal is output, and the blockage of sand and scale migration in the wellbore is interpreted based on the output signal.

2. A numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas well according to claim 1, It is characterized in that The basic geological engineering parameters include pipe string structure, bottom hole fluid temperature, bottom hole flow pressure, gas production, oil production, and geothermal gradient.

3. A numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas well according to claim 2, It is characterized in that The geometric model is obtained specifically by converting the pipe string parameters into linear Lagrangian units and quadratic Lagrangian units, and establishing the geometric model according to the linear Lagrangian units and quadratic Lagrangian units.

4. A numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas well according to claim 1, It is characterized in that The iterative fitting indices include pressure index, velocity field index, turbulence kinetic energy index and specific loss rate index.

5. The method for numerical simulation of sand and scale migration in a high-temperature and high-pressure gas well according to claim 1, It is characterized in that The iterative fitting index obtained according to the fluid flow pattern and particle tracking coupling model is as follows: Based on the fluid flow pattern and particle tracking coupling model, the gas production, oil production and pressure parameters in the basic geological engineering parameters are established as an asymmetric matrix of multi-factor dependent variables of fluid velocity and pressure dynamic changes using the orthogonal null space function, and the pressure and velocity field indices are scaled to obtain them. Then, based on the orthogonal null space function, an asymmetric matrix of turbulence variables is established, which is scaled to form the turbulent kinetic energy and specific loss rate indices.

6. A numerical simulation method for sand and scale migration in a high-temperature and high-pressure gas well according to claim 1, It is characterized in that The specific operation time iteration is as follows: the fluid-solid transport time is divided into n steps, the separation group error estimate and the separation group residual estimate at each time step are approximated, and the pseudo time step CFL ratio at each step is constructed.

7. The method for numerical simulation of sand and scale migration in a high-temperature and high-pressure gas well according to claim 1, It is characterized in that The explanation of the blockage of sand and scale migration in the wellbore based on the output signal is as follows: The pseudo-time step CFL ratio of each iteration is calculated, and the n-th pseudo-time step CFL ratio is used as the actual adaptive control output signal. The actual adaptive control output signal is used to characterize the characteristics of the migration of sand and scale particles as the fluid flows in the wellbore, and the variables of the influencing factors are controlled. The trend of the influence of the changes in various factors on the wellbore blockage is studied, so as to explain the blockage of sand and scale migration in the wellbore.

8. A numerical simulation system for sand and scale migration in high-temperature and high-pressure gas wells. It is characterized in that include: Establishment module: used to establish geometric model, fluid flow field and sand scale particle tracking field according to basic geological engineering parameters; Model building module: used to build a fluid flow pattern and particle tracking coupling model based on the geometric model, fluid flow field and sand and scale particle tracking field; Index acquisition module: used to obtain iterative fitting index according to the fluid flow pattern and particle tracking coupling model; Iteration module: separates group error estimates and separates residual estimates for iterative fit indices, and then runs long iterations; Output module: Set the output signal range. When the iteration value reaches the output signal range, output the signal. Based on the output signal, interpret the blockage of sand and scale migration in the wellbore.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, It is characterized in that When the processor executes the computer program, the steps of the method for numerical simulation of sand and scale migration in a high-temperature and high-pressure gas wellbore are implemented as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program. It is characterized in that When the computer program is executed by a processor, the steps of a method for numerically simulating sand and scale migration in a high-temperature and high-pressure gas wellbore are implemented as described in any one of claims 1 to 7.

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