An injection-production working condition oil-casing annulus normal pressure value calculation method, device and storage medium

Abstract

A kind of injection-production working condition under oil casing annulus normal pressure value calculation method, device and storage medium, the method includes steps: calculating the volume change value caused by tubing internal and external pressure and temperature change;Calculate the annulus volume change value caused by temperature and pressure change;The difference between the tubing volume change value and the annulus volume change value is calculated;Determine the left and right boundary points of the difference;Approach gradually zero point of difference in corresponding left and right boundary points;Calculate the annulus pressure stable value corresponding to the current difference.This application provides a kind of injection-production working condition under oil casing annulus normal pressure value calculation method, device and storage medium, for the normal pressure situation of oil casing annulus in injection-production process of gas storage and other injection-production gas well, from the volume balance of tubing and oil casing annulus, construct mathematical model, apply dichotomy, programming is solved normal pressure value under stable state of oil casing annulus, to accurately judge the operating condition of gas storage and other injection-production gas well.

Description

Technical Field

[0001] This invention belongs to the field of cementing technology for oilfield thermal recovery wells, specifically relating to a method, device, and storage medium for calculating the normal pressure value of the annulus under injection and production conditions. Background Technology

[0002] The construction and safe operation of gas storage clusters are crucial guarantees for peak gas supply regulation, national gas consumption, and even the stable and controllable national energy supply. During the injection and production process of gas wells in gas storage facilities, the temperature and pressure changes of the injected gas will cause coupled changes in the volume of the tubing string and the annulus, ultimately resulting in a certain stable pressure in the annulus. This is a normal pressurized phenomenon during the injection and production process and is not an abnormal annulus pressure caused by leakage in the tubing or other parts.

[0003] The current method for calculating the normal pressure value of the annulus of gas injection and production wells such as gas storage tanks is based on a mathematical model constructed on the radial displacement balance between the tubing and the annulus. However, the physical logic does not fully reflect the actual situation and needs to be improved. Summary of the Invention

[0004] In view of the above problems, the present invention provides a method, apparatus and storage medium for calculating the normal pressure value of the annulus under injection and production conditions to overcome or at least partially solve the above problems.

[0005] To solve the above technical problems, this invention provides a method for calculating the normal pressure value of the annulus under injection and production conditions, the method comprising the following steps:

[0006] Calculate the change in tubing volume caused by changes in internal and external pressure and temperature;

[0007] Calculate the change in annular volume caused by the temperature and pressure changes in the annulus of the oil jacket;

[0008] Calculate the difference between the change in tubing volume and the change in annulus volume;

[0009] Determine the left and right boundary points of the difference;

[0010] The difference gradually approaches zero within the corresponding left and right boundary points;

[0011] Calculate the stable annular pressure value corresponding to the current difference.

[0012] Preferably, the expression for the change in oil pipe volume is:

[0013] ;

[0014] in, This indicates the change in tubing volume. Represents pi (π). Indicates the length from the wellhead to the packer. Indicates the Poisson's ratio of the oil pipeline. This indicates the elastic modulus of the tubing. Indicates the outer diameter of the oil pipe. Indicates the inner diameter of the oil pipe. This indicates the change in pressure within the oil pipe. This indicates the change in annular pressure. This represents the coefficient of thermal expansion of the oil pipe. This indicates the change in oil pipe temperature.

[0015] Preferably, the expression for the annular volume change value is:

[0016] ;

[0017] in, This represents the change in annular volume. Indicates the volume of the protective fluid in the annulus of the oil jacket. This indicates the coefficient of thermal expansion of the annular protective fluid in the oil jacket. Indicates the amount of temperature change. Indicates the compressibility coefficient of the annular protective fluid. This indicates the change in annular pressure. This indicates the initial temperature of the nitrogen column in the annulus of the oil casing. This indicates the initial pressure of the nitrogen column in the annulus of the oil casing. This indicates the length of the nitrogen column in the annulus of the oil jacket. This indicates the cross-sectional area of ​​the oil jacket annulus.

[0018] Preferably, determining the left and right boundary points of the difference includes the following steps:

[0019] The initial annular pressure change is set to 0.

[0020] Select the step size and step size node;

[0021] Calculate the corresponding difference value at each step size node;

[0022] Determine the left and right boundary points when the difference corresponds to a value of zero.

[0023] Preferably, the step of gradually approaching the zero difference point within the corresponding left and right boundary points includes the following steps:

[0024] Within the corresponding left and right boundary points, the difference zero point is gradually approximated using the bisection method until the preset accuracy is achieved.

[0025] Preferably, the step of gradually approximating the zero difference point within the corresponding left and right boundary points using the bisection method until a preset accuracy is achieved includes the following steps:

[0026] The initial annular pressure change is set to 0.

[0027] Calculate the changes in tubing volume, annulus volume, annulus pressure, and their differences at each long node step;

[0028] Determine whether the difference between the current step size node and the adjacent previous step size node has the same sign;

[0029] If so, increase the step size for the current first annular pressure change value, and calculate the tubing volume change value, annular volume change value, second annular pressure change value, and difference value at the next long node;

[0030] If not, take the change value of the third ring air pressure at the adjacent previous step long node as the left boundary, and take the change value of the first ring air pressure at the current step long node as the right boundary.

[0031] Calculate the average of the first annular pressure change value and the third annular pressure change value;

[0032] Calculate the difference corresponding to the average value;

[0033] Determine whether the difference meets the preset precision;

[0034] If so, stop the calculation;

[0035] If not, determine whether the difference between the current step size node and the adjacent previous step size node has the same sign;

[0036] If so, take the first annular pressure change value as the left boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value;

[0037] If not, take the first annular pressure change value as the right boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value.

[0038] Preferably, calculating the stable annular pressure value corresponding to the current difference includes the following steps:

[0039] Obtain the initial pressure of the nitrogen column in the annulus of the oil jacket;

[0040] Calculate the current annular pressure change;

[0041] Calculate the sum of the initial pressure of the nitrogen column in the annulus of the oil jacket and the current change in annulus pressure;

[0042] The sum is used as the stable value of the annular pressure.

[0043] This application also provides a device for calculating the normal pressure value of the annulus under injection and production conditions, including:

[0044] The tubing volume change calculation module is used to calculate the tubing volume change caused by changes in internal and external pressure and temperature.

[0045] The annular volume change calculation module is used to calculate the annular volume change caused by changes in temperature and pressure in the oil casing annulus.

[0046] The difference calculation module is used to calculate the difference between the change in the tubing volume and the change in the annulus volume;

[0047] The left and right boundary point determination module is used to determine the left and right boundary points of the difference;

[0048] The difference zero-point approximation module is used to gradually approach the difference zero point within the corresponding left and right boundary points;

[0049] The annular pressure stability value calculation module is used to calculate the annular pressure stability value corresponding to the current difference.

[0050] This application also provides an electronic device, the electronic device comprising:

[0051] At least one processor; and,

[0052] A memory communicatively connected to the at least one processor; wherein,

[0053] The memory stores instructions that can be executed by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform the method for calculating the normal pressure value of the annulus under any of the aforementioned injection and production conditions.

[0054] This application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to execute the method for calculating the normal pressure value of the annulus under any of the aforementioned injection and production conditions.

[0055] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages: The method, device and storage medium for calculating the normal pressure value of the annulus under injection and production conditions provided in this application are aimed at the normal pressure condition of the annulus under injection and production conditions in gas wells such as gas storage facilities. Starting from the volume balance between the tubing and the annulus, a mathematical model is constructed, and the bisection method is applied to programmatically solve the normal pressure value under the stable state of the annulus, thereby accurately judging the operating status of gas wells such as gas storage facilities. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a flowchart illustrating a method for calculating the normal pressure value of the annulus under injection and production conditions, provided in an embodiment of the present invention.

[0058] Figure 2 This is a flowchart illustrating a method for calculating the normal pressure value of the annulus under injection and production conditions, provided in an embodiment of the present invention.

[0059] Figure 3 This is a schematic diagram of a device for calculating the normal pressure value of the annulus under injection and production conditions, provided in an embodiment of the present invention.

[0060] Figure 4 This is a schematic diagram of the structure of an electronic device provided by the present invention;

[0061] Figure 5 This is a schematic diagram of the structure of a non-transitory computer-readable storage medium provided by the present invention. Detailed Implementation

[0062] The present invention will be described in detail below with reference to specific embodiments and examples, thereby making the advantages and various effects of the present invention more clearly apparent. Those skilled in the art should understand that these specific embodiments and examples are for illustrative purposes only and are not intended to limit the present invention.

[0063] Throughout this specification, unless otherwise specified, the terminology used herein should be understood as having the meaning commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the event of any conflict, this specification shall prevail.

[0064] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0065] like Figure 1 In this embodiment of the application, the present invention provides a method for calculating the normal pressure value of the annulus under injection and production conditions, the method comprising the following steps:

[0066] S1: Calculate the change in tubing volume caused by changes in internal and external pressure and temperature;

[0067] In this embodiment of the application, the expression for the change in the oil pipe volume is:

[0068] ;

[0069] in, This indicates the change in tubing volume. Represents pi (π). Indicates the length from the wellhead to the packer. Indicates the Poisson's ratio of the oil pipeline. This indicates the elastic modulus of the tubing. Indicates the outer diameter of the oil pipe. Indicates the inner diameter of the oil pipe. This indicates the change in pressure within the oil pipe. This indicates the change in annular pressure. This represents the coefficient of thermal expansion of the oil pipe. This indicates the change in oil pipe temperature.

[0070] In this embodiment, the change in tubing volume can be obtained by using an expression for the change in tubing volume and by detecting the parameters in the expression using a detection instrument. .

[0071] S2: Calculate the change in annular volume caused by the temperature and pressure changes in the annulus of the oil jacket;

[0072] In this embodiment of the application, the expression for the annular volume change value is:

[0073] ;

[0074] in, This represents the change in annular volume. Indicates the volume of the protective fluid in the annulus of the oil jacket. This indicates the coefficient of thermal expansion of the annular protective fluid in the oil jacket. Indicates the amount of temperature change. Indicates the compressibility coefficient of the annular protective fluid. This indicates the change in annular pressure. This indicates the initial temperature of the nitrogen column in the annulus of the oil casing. This indicates the initial pressure of the nitrogen column in the annulus of the oil casing. This indicates the length of the nitrogen column in the annulus of the oil jacket. This indicates the cross-sectional area of ​​the oil jacket annulus.

[0075] In this embodiment, the annular volume change value can be obtained by using the expression for the annular volume change value and by detecting each parameter in the expression using a detection instrument. .

[0076] S3: Calculate the difference between the change in tubing volume and the change in annulus volume;

[0077] In this embodiment of the application, the difference y= ΔV i - ΔV o

[0078] S4: Determine the left and right boundary points of the difference;

[0079] In this embodiment of the application, determining the left and right boundary points of the difference includes the following steps:

[0080] The initial annular pressure change is set to 0.

[0081] Select the step size and step size node;

[0082] Calculate the corresponding difference value at each step size node;

[0083] Determine the left and right boundary points when the difference corresponds to a value of zero.

[0084] In this embodiment, during the injection and production process of the gas injection well, when the annular pressure is normal and stable, the change in tubing volume ΔVi (with the tubing outer diameter as the boundary) caused by the changes in pressure and temperature inside and outside the tubing should be equal to the change in annular volume ΔVo caused by the changes in annular temperature and pressure, i.e., ΔVi = ΔVo. At this time, let y = ΔVi - ΔVo, set the initial Δpo = 0, and calculate the yn value at each step node (n represents the step node) with a step size of 1 MPa, and determine the left and right boundary points of the zero point of y.

[0085] S5: Gradually approach the zero point of the difference within the corresponding left and right boundary points;

[0086] In this embodiment of the application, the step of gradually approaching the zero difference point within the corresponding left and right boundary points includes the following steps:

[0087] Within the corresponding left and right boundary points, the difference zero point is gradually approximated using the bisection method until the preset accuracy is achieved.

[0088] In this embodiment of the application, the zero point of y is approximated by the bisection method within the left and right boundary points until the required accuracy is achieved.

[0089] In this embodiment of the application, the step of gradually approximating the zero difference point within the corresponding left and right boundary points using the bisection method until a preset accuracy is achieved includes the following steps:

[0090] The initial annular pressure change is set to 0.

[0091] Calculate the changes in tubing volume, annulus volume, annulus pressure, and their differences at each long node step;

[0092] Determine whether the difference between the current step size node and the adjacent previous step size node has the same sign;

[0093] If so, increase the step size for the current first annular pressure change value, and calculate the tubing volume change value, annular volume change value, second annular pressure change value, and difference value at the next long node;

[0094] If not, take the change value of the third ring air pressure at the adjacent previous step long node as the left boundary, and take the change value of the first ring air pressure at the current step long node as the right boundary.

[0095] Calculate the average of the first annular pressure change value and the third annular pressure change value;

[0096] Calculate the difference corresponding to the average value;

[0097] Determine whether the difference meets the preset precision;

[0098] If so, stop the calculation;

[0099] If not, determine whether the difference between the current step size node and the adjacent previous step size node has the same sign;

[0100] If so, take the first annular pressure change value as the left boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value;

[0101] If not, take the first annular pressure change value as the right boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value.

[0102] like Figure 3 In this embodiment of the application, the calculation steps are as follows:

[0103] (1) Assume that the initial change in annular pressure Δpo = 0;

[0104] (2) Calculate the values ​​of ΔVin, ΔVon, and yn at the step size node (n represents the step size node);

[0105] (3) Determine whether the y-value of the previous node and the current node have the same sign. If yn-1·yn>0, then let ΔPo=ΔPo+1, return to step (2), and proceed to the calculation of the next node; if yn-1·yn<0, then proceed to step (4);

[0106] (4) The left boundary of the bisection method is Δpo at node n-1, and is set as Δpo1; the right boundary of the bisection method is Δpo2 at node n.

[0107] (5) Let Δpo = (Δpo1 + Δpo2) / 2, and calculate the y value under Δpo. If |y| meets the accuracy requirements, the calculation ends and PN + Δpo is the final annular stable band pressure value; if |y| does not meet the accuracy requirements, proceed to step (6).

[0108] (6) Determine whether the y value at this time has the same sign as the y value under node n-1. If y•yn-1>0, then let Δpo1=Δpo and return to step (5); if y•yn-1<0, then let Δpo2=Δpo and return to step (5).

[0109] S6: Calculate the stable annular pressure value corresponding to the current difference.

[0110] In this embodiment of the application, calculating the stable annular pressure value corresponding to the current difference includes the following steps:

[0111] Obtain the initial pressure of the nitrogen column in the annulus of the oil jacket;

[0112] Calculate the current annular pressure change;

[0113] Calculate the sum of the initial pressure of the nitrogen column in the annulus of the oil jacket and the current change in annulus pressure;

[0114] The sum is used as the stable value of the annular pressure.

[0115] In this embodiment of the application, when the difference is within a preset accuracy, Δpo is the stable normal pressure change of the annulus, and pN+Δpo is the final stable value of the annulus pressure.

[0116] like Figure 2 In this embodiment of the application, the application also provides a device for calculating the normal pressure value of the annulus under injection and production conditions, comprising:

[0117] The tubing volume change calculation module 10 is used to calculate the tubing volume change caused by changes in internal and external pressure and temperature.

[0118] The annular volume change calculation module 20 is used to calculate the annular volume change caused by the temperature and pressure changes in the oil casing annulus.

[0119] The difference calculation module 30 is used to calculate the difference between the change in the tubing volume and the change in the annulus volume;

[0120] Left and right boundary point determination module 40 is used to determine the left and right boundary points of the difference;

[0121] The difference zero-point approximation module 50 is used to gradually approximate the difference zero point within the corresponding left and right boundary points;

[0122] The annular pressure stability value calculation module 60 is used to calculate the annular pressure stability value corresponding to the current difference.

[0123] The automatic well vibration calibration device provided in this application can perform the automatic well vibration calibration method provided in the above steps.

[0124] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

[0125] The following is for reference. Figure 4 The diagram illustrates a structural schematic of an electronic device 100 suitable for implementing embodiments of the present disclosure. The electronic devices in the embodiments of the present disclosure may include, but are not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 4 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments disclosed herein.

[0126] like Figure 4 As shown, the electronic device 100 may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 101, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 102 or a program loaded from a storage device 108 into a random access memory (RAM) 103. The RAM 103 also stores various programs and data required for the operation of the electronic device 100. The processing unit 101, ROM 102, and RAM 103 are interconnected via a bus 104. An input / output (I / O) interface 105 is also connected to the bus 104.

[0127] Typically, the following devices can be connected to I / O interface 105: input devices 106 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 107 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 108 including, for example, magnetic tapes, hard disks, etc.; and communication devices 109. Communication device 109 allows electronic device 100 to communicate wirelessly or wiredly with other devices to exchange data. Although an electronic device 100 with various devices is shown in the figure, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively.

[0128] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication device 109, or installed from storage device 108, or installed from ROM 102. When the computer program is executed by processing device 101, it performs the functions defined in the methods of embodiments of this disclosure.

[0129] The following is for reference. Figure 5 It illustrates a schematic diagram of a computer-readable storage medium suitable for implementing embodiments of the present disclosure, the computer-readable storage medium storing a computer program that, when executed by a processor, can implement the multi-scale component model finite element mesh generation method as described above.

[0130] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0131] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0132] The aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: acquire at least two Internet Protocol (IP) addresses; send a node evaluation request including the at least two IP addresses to a node evaluation device, wherein the node evaluation device selects an IP address from the at least two IP addresses and returns it; and receive the IP address returned by the node evaluation device; wherein the acquired IP address indicates an edge node in a content delivery network.

[0133] Alternatively, the aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: receive a node evaluation request including at least two Internet Protocol (IP) addresses; select an IP address from the at least two IP addresses; and return the selected IP address; wherein the received IP address indicates an edge node in the content delivery network.

[0134] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0135] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0136] The units described in the embodiments of this disclosure can be implemented in software or in hardware. The name of a unit does not necessarily limit the unit itself; for example, the first acquisition unit can also be described as "a unit that acquires at least two Internet Protocol addresses".

[0137] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The above descriptions are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

[0138] This application provides a method, device, and storage medium for calculating the normal pressure value of the annulus under injection and production conditions. Targeting the normal pressure condition of the annulus during the injection and production process of gas wells such as gas storage facilities, a mathematical model is constructed based on the volume balance between the tubing and the annulus. The bisection method is applied, and the normal pressure value under stable conditions of the annulus is solved by programming, thereby accurately determining the operating status of gas wells such as gas storage facilities.

[0139] In summary, the above description is merely a preferred embodiment of the technical solution of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calculating the normal pressure value of the annulus under injection and production conditions, characterized in that, The method includes the following steps: Calculate the change in tubing volume caused by changes in internal and external pressure and temperature; Calculate the change in annular volume caused by the temperature and pressure changes in the annulus of the oil jacket; Calculate the difference between the change in tubing volume and the change in annulus volume; Determine the left and right boundary points of the difference; The difference gradually approaches zero within the corresponding left and right boundary points; Calculate the stable annular pressure value corresponding to the current difference; The expression for the change in the volume of the oil pipe is: ； in, This indicates the change in tubing volume. Represents pi (π). Indicates the length from the wellhead to the packer. Indicates the Poisson's ratio of the oil pipeline. This indicates the elastic modulus of the tubing. Indicates the outer diameter of the oil pipe. Indicates the inner diameter of the oil pipe. This indicates the change in pressure within the oil pipe. This indicates the change in annular pressure. This represents the coefficient of thermal expansion of the oil pipe. This indicates the change in oil pipe temperature; The expression for the annular volume change value is: ； in, This represents the change in annular volume. Indicates the volume of the protective fluid in the annulus of the oil jacket. This indicates the coefficient of thermal expansion of the annular protective fluid in the oil jacket. Indicates the amount of temperature change. Indicates the compressibility coefficient of the annular protective fluid. This indicates the change in annular pressure. This indicates the initial temperature of the nitrogen column in the annulus of the oil casing. This indicates the initial pressure of the nitrogen column in the annulus of the oil casing. This indicates the length of the nitrogen column in the annulus of the oil jacket. This represents the cross-sectional area of ​​the oil jacket annulus; The step of gradually approaching the zero difference point within the corresponding left and right boundary points includes the following steps: Within the corresponding left and right boundary points, the difference zero point is gradually approximated using the bisection method until the preset accuracy is achieved; The step of gradually approximating the zero difference point within the corresponding left and right boundary points using the bisection method until a preset accuracy is achieved includes the following steps: The initial annular pressure change is set to 0. Calculate the changes in tubing volume, annulus volume, annulus pressure, and their differences at each long node step; Determine whether the difference between the current step size node and the adjacent previous step size node has the same sign; If so, increase the step size for the current first annular pressure change value, and calculate the tubing volume change value, annular volume change value, second annular pressure change value, and difference value at the next long node; If not, take the change value of the third ring air pressure at the adjacent previous step long node as the left boundary, and take the change value of the first ring air pressure at the current step long node as the right boundary; Calculate the average of the first annular pressure change value and the third annular pressure change value; Calculate the difference corresponding to the average value; Determine whether the difference meets the preset precision; If so, stop the calculation; If not, determine whether the difference between the current step size node and the adjacent previous step size node has the same sign; If so, take the first annular pressure change value as the left boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value; If not, take the first annular pressure change value as the right boundary and return to the step of calculating the average value of the first annular pressure change value and the third annular pressure change value.

2. The method for calculating the normal pressure value of the annulus under injection and production conditions according to claim 1, characterized in that, Determining the left and right boundary points of the difference includes the following steps: The initial annular pressure change is set to 0. Select the step size and step size node; Calculate the corresponding difference value at each step size node; Determine the left and right boundary points when the difference corresponds to a value of zero.

3. The method for calculating the normal pressure value of the annulus under injection and production conditions according to claim 1, characterized in that, The calculation of the stable annular pressure value corresponding to the current difference includes the following steps: Obtain the initial pressure of the nitrogen column in the annulus of the oil jacket; Calculate the current annular pressure change; Calculate the sum of the initial pressure of the nitrogen column in the annulus of the oil jacket and the current change in annulus pressure; The sum is taken as the stable value of the annular pressure.

4. A device for calculating the normal pressure value of the annulus under injection and production conditions, applicable to the method described in any one of claims 1-3, characterized in that, include: The tubing volume change calculation module is used to calculate the tubing volume change caused by changes in internal and external pressure and temperature. The annular volume change calculation module is used to calculate the annular volume change caused by changes in temperature and pressure in the oil casing annulus. The difference calculation module is used to calculate the difference between the change in the tubing volume and the change in the annulus volume; The left and right boundary point determination module is used to determine the left and right boundary points of the difference; The difference zero-point approximation module is used to gradually approach the difference zero point within the corresponding left and right boundary points; The annular pressure stability value calculation module is used to calculate the annular pressure stability value corresponding to the current difference.

5. An electronic device, characterized in that, The electronic device includes: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, which, when executed by the at least one processor, enables the at least one processor to perform the method for calculating the normal pressure value of the annulus under injection and production conditions as described in any one of claims 1-3.

6. A non-transitory computer-readable storage medium storing computer instructions for causing the computer to execute the method for calculating the normal pressure value of the annulus under injection and production conditions as described in any one of claims 1-3.

Images