Annular gas-liquid two-phase initial condition calculation method and device for transient well killing simulation, equipment and medium

Abstract

The invention discloses an annular gas-liquid two-phase initial condition calculation method, device, equipment and medium for transient well killing simulation, and the method comprises the steps: collecting well mouth parameters in real time after overflow is detected and well shut-in operation is completed; calculating a formation pressure value and an initial trial calculation height according to the wellhead parameters; according to the formation pressure and the volume of the mixed-phase section, the total mole number of gas contained in the mixed-phase section is determined; calculating from the bottom end of a mixed-phase section, namely a shaft bottom position, setting initial pressure and temperature parameters, and solving the temperature and the pressure of a calculation point and the gas phase volume and the mixed-phase density in the height of each section based on the total mole number of gas and the initial trial calculation height; and comparing the calculated top end pressure of the mixed-phase section with the sum of the actually measured shut-in casing pressure and the upper hydrostatic column pressure, if preset conditions are met, outputting the calculated temperature, pressure, gas phase volume and mixed-phase density, and if the preset conditions are not met, performing calculation again. Therefore, the calculation precision of the initial condition under the gas cut working condition is remarkably improved.

Description

TECHNICAL FIELD

[0001] The application relates to an annular gas-liquid two-phase initial condition calculation method, device, equipment and medium for transient kill well simulation, and relates to the technical field of oil and gas well pressure control. BACKGROUND

[0002] In the process of oil and gas resource development, with the deepening of exploration and development, the proportion of high-gas-content strata, fractured gas reservoirs and high-pressure gas layers gradually increases, and the risk of gas invasion significantly rises. Especially when drilling in the fracture development area, abnormally high pressure gas layer or narrow safety density window and shallow gas-rich strata, the phenomenon of stratum fluid invasion into the wellbore frequently occurs, which easily induces well control risks such as gas surge and blowout. In view of this challenge, how to quickly and safely control gas invasion and restore the pressure balance of the wellbore becomes a key problem. Under this background, the kill well technology as a core means to cope with gas invasion is becoming increasingly important. The key of the technology is to effectively exclude the gas in the well through reasonable process measures, quickly rebuild the pressure balance of the wellbore, and thus ensure the safety of drilling operations.

[0003] At present, although most of the researches on kill well algorithms adopt the transient analysis method, there is still a significant numerical dissipation problem in the solving process of the partial differential equation set. The reason is mainly that the simplification of the initial condition has a theoretical defect: the existing method simplifies the invaded gas after the well is closed as a static pure gas column model, without considering the drift motion of the gas due to the density difference in the gas invasion process, and also ignoring the dynamic expansion effect of the gas under the change of the annular pressure. In fact, after the well is successfully closed, the wellbore is affected by the double effects of gas migration and expansion, and a non-uniform gas-liquid two-phase distribution state is formed in the wellbore, rather than the pure gas column structure assumed in theory. This idealized initial condition setting seriously affects the calculation accuracy and engineering applicability of the kill well algorithm.

[0004] Therefore, it is urgent to establish an accurate kill well initial condition calculation method suitable for different gas invasion conditions, to build a dynamic model capable of accurately representing the real gas-liquid distribution state in the wellbore after the well is closed by deeply studying the gas migration and expansion characteristics, and to provide scientific and reliable kill well process guidance for drilling sites. SUMMARY

[0005] The present application aims at solving at least one of the problems existing in the prior art. To this end, the present application aims at providing a method for calculating the initial conditions of the annular gas-liquid two-phase for transient kill well simulation, which can accurately calculate the height distribution of the overflow mixed phase section in the wellbore after the well is closed, the real-time gas holdup of each grid unit and the annular pressure profile, and provide reliable initial operating condition parameters for subsequent kill well operations.

[0006] To achieve the above object, the present application adopts the technical scheme of: In the first aspect, the present application provides an annular gas-liquid two-phase initial condition calculation method for transient kill well simulation, comprising: After detecting overflow and completing the shut-in operation, real-time acquisition of wellhead parameters is performed; According to the wellhead parameters, the formation pressure value is calculated And the initial trial height ; According to the formation pressure And the volume of the miscible phase section, the total number of moles of gas contained in the miscible phase section is determined; Starting from the bottom of the miscible phase section, i.e. the well bottom position, the initial pressure and temperature parameters are set, and based on the total number of moles of gas and the initial trial height The temperature, pressure and gas phase volume and miscible phase density in each height of the calculation point are solved; The calculated top pressure of the miscible phase section is compared with the sum of the measured shut-in casing pressure and the upper static liquid column pressure, and if the preset condition is met, the calculated temperature, pressure, gas phase volume and miscible phase density are output, and if the preset condition is not met, the calculation is performed again.

[0007] In some possible implementation manners, the wellhead parameters include the shut-in casing pressure, the overflow volume and the drilling fluid density.

[0008] In some possible implementation manners, the formation pressure value : ; In the formula, P d0 is the shut-in casing pressure, g is the acceleration of gravity, H is the depth of the well, is the drilling fluid density.

[0009] In some possible implementation manners, the calculation formula of the initial trial height is: ; In the formula, is the annular cross-sectional area, V g0 is the initial overflow volume.

[0010] In some possible implementation manners, the temperature, pressure and gas phase volume and miscible phase density in each height of the calculation point are solved, specifically: The calculation formula of the temperature is: ; In the formula, T 0 is the ground temperature, T aThe geothermal gradient is: The pressure P The calculation formula of the gas phase volume is:

[0011]

[0012] The calculation formula of the gas phase volume is:

[0013] In the formula, Z is the compressibility factor, R is the ideal gas constant, n is the number of moles of gas, M is the relative molecular mass of the gas, P b is the bottom hole pressure, Z b is the size of the natural gas compression factor when located at the bottom of the well, H s is the height of the well depth of the calculation point, T b is the temperature at the bottom of the well, n all is the number of moles of gas in the entire wellbore; The calculation formula of the gas phase density and the liquid phase density is:

[0014] In the formula, is the liquid phase density under standard conditions, is the pressure under standard conditions, is the gas phase sound speed; The calculation formula of the gas phase and liquid phase volume fraction is:

[0015]

[0016] The calculation formula of the mixed phase density is: .

[0017] In some possible implementation manners, the preset condition is: If , the measurement is re-measured according to the measurement process; If , the following judgment is further performed:

[0018] In the formula, is the pressure at the top of the current calculation section; is the set annulus pressure reference value; If yes, the output mixed overflow height is j If no, the output mixed overflow height is j- 1, and the calculated temperature, pressure, gas volume and mixed density are output.

[0019] In a second aspect, the application further provides an annular gas-liquid two-phase initial condition calculation device for transient kill well simulation, comprising: The parameter acquisition unit is configured to acquire wellhead parameters in real time after detecting overflow and completing the shut-in operation; The first calculation unit is configured to calculate the formation pressure value and the initial trial height according to the wellhead parameters. The second calculation unit is configured to determine the total number of moles of gas contained in the mixed phase section according to the formation pressure and the mixed phase section volume. The third calculation unit is configured to calculate from the bottom end of the mixed phase section, i.e., the well bottom position, set initial pressure and temperature parameters, and solve the temperature, pressure and gas volume and mixed density in each height according to the total number of moles of gas and the initial trial height . The result judgment and output unit is configured to compare the calculated top pressure of the mixed phase section with the sum of the measured shut-in casing pressure and the upper static liquid column pressure, and if the preset condition is met, output the calculated temperature, pressure, gas volume and mixed density, and if the preset condition is not met, re-measure according to the measurement process.

[0020] In a third aspect, the application further provides an electronic device, comprising at least one processor and a memory connected in communication with the processor, wherein the memory stores instructions executable by the processor, and the instructions are executed by the processor to enable the processor to execute the method.

[0021] In a fourth aspect, the application further provides a computer-readable storage medium storing one or more programs, wherein the one or more programs comprise computer instructions for causing a computer to execute the method.

[0022] The application has the following characteristics due to the above technical solutions: 1. The accurate kill well initial condition calculation method based on a dynamic gas-liquid distribution model provided by the application realizes accurate characterization of the distribution state of gas-liquid two phases in the wellbore after shut-in by establishing multiphase flow control equations considering gas migration-expansion coupling effects, using high-precision grid division technology and iterative solution algorithms.

[0023] 2、The application can accurately calculate the height distribution of the overflow mixed phase section in the wellbore after the well is closed, the real-time gas content of each grid unit, and the annular pressure profile, thereby providing reliable initial working condition parameters for subsequent well killing operations, compared with the traditional method of simplifying the wellbore gas as a pure gas column assumption, the application is more in line with the actual gas invasion dynamic characteristics, and the accuracy and reliability of the well killing process design can be significantly improved.

[0024] 3、The application innovatively combines the gas state equation, the micro-element analysis method and the closure law, establishes a set of high-precision transient well killing annular two-phase flow calculation model, and through mathematical integral theory, key well closing parameters are brought into the solution system, and the dynamic distribution characteristics caused by the drift velocity in the gas migration process and the accompanying pressure change and volume expansion effect are mainly considered.Although the specific value of the drift flow velocity is not directly calculated, through the establishment of a reasonable physical model and mathematical relationship, the overall influence of the drift flow velocity on the gas-liquid distribution can be accurately reflected.

[0025] In summary, the application effectively solves the technical limitations that the traditional model cannot accurately describe the gas migration effect, significantly improves the calculation accuracy of the initial conditions under gas invasion conditions, and provides a more reliable theoretical basis and technical support for well killing operations in complex formations. BRIEF DESCRIPTION OF DRAWINGS

[0026] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not meant to limit the present application. Throughout the drawings, the same reference designators are employed to designate the same elements. In the drawings: Figure 1 The flow chart of the annular gas-liquid two-phase initial condition calculation of the transient well killing of the embodiment of the application; Figure 2 The wellbore grid division schematic diagram of the embodiment of the application; Figure 3 The distribution rule of the cross-sectional gas content with the well depth of the embodiment of the application; Figure 4 The distribution rule of the cross-sectional annular pressure with the well depth of the embodiment of the application; Figure 5 The electronic device structure diagram of the embodiment of the application. DETAILED DESCRIPTION

[0027] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order

[0028] Although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0029] Spatially relative terms, such as "inner", "outer", "beneath", "below", "lower", "above", "upper", and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms can be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0030] The annulus gas-liquid two-phase initial condition calculation method, device, equipment and medium for transient kill well simulation provided by the application comprise the following steps: after overflow is detected and a shut-in operation is completed, wellhead parameters are collected in real time; a formation pressure value is calculated according to the wellhead parameters and an initial trial height ; the total number of moles of gas contained in a miscible phase section is determined according to the formation pressure and the volume of the miscible phase section; starting from the bottom end of the miscible phase section, that is, the bottom hole position, initial pressure and temperature parameters are set, and the total number of moles of gas and the initial trial height Solve the temperature, pressure and gas volume and mixed phase density in each height of the calculation point; compare the calculated mixed phase section top pressure with the sum of the measured casing pressure and the upper static column pressure, if the preset condition is met, output the calculated temperature, pressure, gas volume and mixed phase density, if the preset condition is not met, recalculate. Therefore, the technical limitation that the traditional model cannot accurately describe the gas migration effect is effectively solved, and the calculation accuracy of the initial condition under the gas invasion condition is significantly improved.

[0031] Exemplary embodiments of the present application will be described in greater detail below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present application can be thoroughly understood and fully conveyed to those skilled in the art.

[0032] The annular gas-liquid two-phase initial condition calculation method for transient kill simulation provided by the embodiment is mainly to establish a mathematical model considering the coupling effect of gas migration-expansion, and the control equation derived therefrom can more accurately represent the non-uniform gas-liquid distribution state in the annulus after shut-in.

[0033] Since the control body mass is the product of the mixed density and the volume, and also represents the sum of the gas and liquid mass, it can be written as:

[0034] In the formula, V is the total volume in the control body, m 3 ; is the overflow mixed phase section density, g / cm 3 ; V g is the gas volume in the control body, m 3 ; is the drilling fluid density, g / cm 3 ; is the gas density at different well depths, g / cm 3 .

[0035] Divide both sides of the above formula by V , to obtain:

[0036] According to the gravity equation:

[0037] In the formula, is the gravity of the control body element section, Pa; g is the acceleration of gravity, 9.81 m / s 2 ; m, to control the depth of the control body micro-element section; According to the real gas state equation:

[0038] In the formula, P P is the annulus pressure at different depths, Pa; Z is the gas compressibility factor at well depth H, dimensionless; T is the temperature at different depths, K; n N is the number of moles of gas in the control body, mol; R is the ideal gas constant, P·m 3 / mol·K; M M is the relative molecular mass of the gas, kg / mol.

[0039] Introduce the closure law:

[0040] Let

[0041] In the formula, ρ is the liquid phase density under standard conditions, 1000 kg / m 3 ; P is the pressure under standard conditions, 10 5 Pa; C is the liquid phase sound speed, 1000 m / s; C is the gas phase sound speed, 316 m / s.

[0042] Substitute the above formula into the gravity equation to get:

[0043] Let: , and simplify to get:

[0044] Integrate the above formula , to get the following formula:

[0045] Where: , C is the indefinite integral constant term.

[0046] When the control body is the entire wellbore, P P b ; H H b , Substitute the above formula to calculate the indefinite integral constant term C :

[0047] There are 5 unknowns in the above formula​​H , P , n , T , Z ), will adopt well depth H Temperature calculation formula and well depth H Compression coefficient Z Calculation formula and total number of gas moles in the overflow miscible section n The three auxiliary formulas are used to solve the equation derived above.

[0048] Based on the mathematical model established by the aforementioned theoretical derivation, this embodiment provides a method for calculating the initial conditions of the annular air-liquid two-phase system for transient well control simulation, including: S1. Obtain wellhead parameters.

[0049] In this embodiment, after the overflow is detected and the well shut-in operation is completed, key parameters such as shut-in casing force, shut-in casing pressure, mud pit increment (overflow), and current drilling fluid density are collected in real time. This is just one example, and is not limited to this.

[0050] S2, Calculate formation pressure value .

[0051] In this embodiment, based on the acquired shut-in casing pressure, drilling fluid density, and current well depth data, the formation pressure value is accurately calculated using the hydrostatic column pressure calculation method. : .

[0052] In the formula, This refers to the casing pressure at the wellhead.

[0053] S3, Calculate the trial height of the mixed phase section .

[0054] In this embodiment, the overflow height calculated using a pure air column model is taken as the initial trial height based on the known increase in the mud pit volume, i.e., the overflow rate. : .

[0055] In the formula, Let m be the cross-sectional area of ​​the annulus. 2 , V g0 For the initial overflow, m 3 .

[0056] Furthermore, in this embodiment, after obtaining the wellhead parameters, the wellbore is meshed by setting a spatial step size. If the initial spatial step size is set too large, the interval where the height of the miscible section is located may not contain a complete mesh. To make the calculation process more consistent with the calculated height of the miscible section, the mesh size is adjusted accordingly. The space grid adjusts the space step, further refines the grid division, and makes the divided grid completely contain the height of the miscible phase section, which is convenient for subsequent calculation.

[0057] S4, determine the total number of moles of gas contained in the miscible phase section.

[0058] In this embodiment, based on the real gas state equation, the total number of moles of gas contained in the miscible phase section is determined according to the calculated formation pressure and the volume of the miscible phase section.

[0059] S5, iterative calculation initialization.

[0060] In this embodiment, the calculation starts from the bottom of the miscible phase section, i.e. the well bottom position, sets the initial pressure and temperature parameters, solves the temperature and pressure of the calculation point and the gas phase volume and miscible density in each section height, and the parameter calculation process is: According to the design initial temperature and temperature gradient formula to solve the calculation point temperature: ; In the formula, T 0 is the ground temperature, T a is the geothermal gradient; Solve the calculation point pressure P :

[0061]

[0062] In the formula, P b is the well bottom pressure, Pa; Z b is the size of natural gas compression factor located at the well bottom; H s is the well depth height of the calculation point, m; T b is the temperature size located at the well bottom, K; n all is the total number of moles of gas in the entire wellbore, mol.

[0063] According to the real state gas equation to solve the gas phase volume:

[0064] According to the above closed law, the gas phase density and liquid phase density are obtained respectively:

[0065] Gas phase and liquid phase volume fraction:

[0066]

[0067] Miscible density: .

[0068] S6, iteratively calculate per grid.

[0069] In this embodiment, the calculation of S5 is repeated for each discrete grid in turn, including determining the gas fraction of the current grid, calculating the pressure gradient, updating the next grid pressure parameter, and considering the gas expansion effect.

[0070] S7, calculate the result.

[0071] In this embodiment, the calculated top pressure of the miscible phase section is compared with the sum of the measured casing pressure and the upper static column pressure. If the preset condition is met, the data calculated in step S5 is output. If the condition is not met, steps S1 to S7 are repeated for calculation.

[0072] The specific process of the annular gas-liquid two-phase initial condition calculation method for transient kill well simulation of the present application will be described in detail below through a gas invasion well as a specific embodiment.

[0073] Before calculation, in order to solve the annulus pressure calculation formula derived by the present application after successful shut-in, three auxiliary formulas are first introduced: (1) Well depth H Fluid temperature at ： wherein, T 0 is the ground temperature, K; T a is the ground temperature gradient, K.

[0074] (2) Well depth H Compressibility coefficient at Z :

[0075] In the formula, A 1=0.3265; A 2=-1.0700; A 3=-0.5339; A 4=0.01569; A 5=-0.05165; A 6=0.5475; A 7=-0.7361; A 8=0.1844; A 9=0.1056; A 10 =0.6134; A11 = 0.7210.

[0076]

[0077] wherein, is the temperature at standard conditions, 273.15 K; is the pressure of the fluid at standard conditions, 10 5 Pa.

[0078] (3) Calculate the total number of moles of gas: calculate the total number of moles of gas based on the linear distribution of the number of moles of gas in the overflow mixed phase along the well depth, wherein the gas density also presents a relative linear distribution, and the calculation formula is:

[0079]

[0080]

[0081] Based on the above auxiliary formula, as shown in the formula (1), the annular gas-liquid two-phase initial condition calculation method for transient kill well simulation provided by the embodiment comprises: Figure 1 Step one: obtain the wellhead parameters. In the embodiment, after detecting overflow and completing the shut-in operation, real-time acquisition is performed on key parameters such as the shut-in casing pressure

[0082] P d0 , the shut-in casing pressure P a0 , the mud pit increment V go , and the current drilling fluid density.

[0083] Step two: calculate the formation pressure according to the obtained shut-in casing pressure P d0 . .

[0084] Step three: calculate the mixed phase test height; .

[0085] wherein, is the annular cross-sectional area, m 2 , V g0 is the initial overflow amount, m 3 . H gas is the pure gas column height, m.

[0086] Step four: solve the cross-sectional annular pressure P by simultaneously solving the following three formulas and the above auxiliary formula.​

[0087]

[0088]

[0089] Step five: calculate the total moles of gas contained in the mixed phase section according to the total amount of gas.

[0090] In this embodiment, based on the real gas state equation, the total moles of gas contained in the mixed phase section are determined according to the calculated formation pressure and the volume of the mixed phase section.

[0091] Step six: iterative calculation of each grid.

[0092] In this embodiment, each discrete grid is calculated in turn, including determining the gas phase fraction of the current grid, calculating the pressure gradient, updating the pressure parameter of the next grid, and considering the gas expansion in combination with the real gas state equation.

[0093] In the formula, P j is the first j The top pressure of the calculation section is MPa. P (j+1)b is the first j+ 1The bottom pressure of the calculation section is MPa.

[0094] Step seven: judge the calculation result.

[0095] In this embodiment, the calculation result is judged, including: If , then steps one to six are performed again. If , the following judgment is made:

[0096] In the formula, is the pressure at the top of the current calculation section, Pa; is the corresponding well depth at the bottom of the current calculation section, m; is the set annulus pressure reference value, Pa.

[0097] If it is satisfied, the mixed overflow height is output as j , and if it is not satisfied, the mixed overflow height is output as j- 1. Through calculation, the mixed overflow phase section is 956 m, and the final output is the key data such as the accurately calculated gas-liquid mixed phase section distribution parameter, annulus pressure value and gas phase fraction of each grid, as shown in the attached Figure 3 , Figure 4 .

[0098] Embodiment Two: The above embodiment one provides an annulus gas-liquid two-phase initial condition calculation method for transient kill simulation. Correspondingly, the present embodiment provides an annulus gas-liquid two-phase initial condition calculation device for transient kill simulation. The device provided by the present embodiment can implement the annulus gas-liquid two-phase initial condition calculation method for transient kill simulation of embodiment one. The device can be realized by software, hardware or a combination of software and hardware. For the convenience of description, the device is described in various units according to functions in the description of the present embodiment. Of course, the functions of the units can be implemented in the same or multiple software and / or hardware in the implementation. For example, the device can include integrated or separate functional modules or functional units to perform the corresponding steps in the methods of embodiment one. Since the device of the present embodiment is basically similar to the method embodiment, the description process of the present embodiment is relatively simple, and the related parts can be referred to the part of the description of embodiment one. The embodiment of the device for annulus gas-liquid two-phase initial condition calculation for transient kill simulation provided by the present application is only illustrative.

[0099] Specifically, the present application also provides an annulus gas-liquid two-phase initial condition calculation device for transient kill simulation, comprising: A parameter acquisition unit configured to collect wellhead parameters in real time after detecting overflow and completing the shut-in operation; A first calculation unit configured to calculate the formation pressure value according to the wellhead parameters And the initial trial height ; A second calculation unit configured to determine the total number of moles of gas contained in the miscible phase section according to the formation pressure And the volume of the miscible phase section; A third calculation unit configured to calculate from the bottom of the miscible phase section, i.e. the bottom hole position, set initial pressure and temperature parameters, based on the total number of moles of gas and the initial trial height Solve the temperature, pressure and gas phase volume and miscible phase density in each height of the calculation point; A result judging and output unit configured to compare the calculated top pressure of the miscible phase section with the sum of the measured shut-in casing pressure and the upper static liquid column pressure, and output the calculated temperature, pressure, gas phase volume and miscible phase density if the preset condition is met, or re-measure according to the measurement process if the preset condition is not met.

[0100] Embodiment Three: The present embodiment provides an electronic device corresponding to the annulus gas-liquid two-phase initial condition calculation method for transient kill simulation provided by embodiment one. The electronic device can be an electronic device for a client, such as a mobile phone, a notebook computer, a tablet computer, a desktop computer, etc., to execute the method of embodiment one.

[0101] As Figure 5As shown, the electronic device includes a processor, a memory, a communication interface, and a bus. The processor, the memory, and the communication interface are connected through the bus to complete communication with each other. The memory stores a computer program that can run on the processor. When the processor runs the computer program, the processor executes the method of Embodiment One, which has similar principles and technical effects to Embodiment One, and details are not repeated here. Those skilled in the art can understand that Figure 5 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computing device to which the scheme of the present application is applied. A specific computing device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0102] In a preferred embodiment, the logical instructions in the memory described above can be implemented in the form of a software function unit and sold or used as a standalone product, which can be stored in a computer-readable storage medium. Based on this understanding, the technical scheme of the present application essentially or the part that contributes to the prior art or part of the technical scheme can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), an optical disc, and various program code storage media.

[0103] In a preferred embodiment, the processor can be a central processing unit (CPU), a digital signal processor (DSP), or various types of general-purpose processors, which are not limited here.

[0104] Embodiment Four: The present embodiment provides a computer-readable storage medium storing one or more programs, the one or more programs including computer instructions that, when executed by a computer, cause the computer to perform the method provided by Embodiment One.

[0105] In a preferred embodiment, the computer-readable storage medium can be a tangible device that maintains and stores program instructions for execution by an instruction execution system, such as, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination of the above. The computer-readable storage medium stores computer program instructions that cause a computer to execute the method provided by Embodiment One.

[0106] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0107] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0108] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 one or more flow or blocks

[0109] In the description of the specification, the description of the terms "one preferred embodiment", "further", "specifically", "in this embodiment", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the embodiments of the specification. In the description of the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0110] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An annulus gas-liquid two-phase initial condition calculation method for transient kill well simulation, characterized in that, The method comprises the following steps: After detecting overflow and completing the shut-in operation, real-time acquisition of wellhead parameters is performed; Calculating formation pressure values from wellhead parameters and initial trial height ; According to the formation pressure and the miscible phase segment volume, the total moles of gas contained in the miscible phase segment are determined; The initial pressure and temperature parameters are set from the bottom of the miscible section, i.e., the well bottom location, based on the total moles of gas and the initial trial height The temperature, pressure, and gas volume and miscible density within each height are solved for the calculation points; The calculated top pressure of the miscible phase section is compared with the sum of the measured shut-in casing pressure and the upper static liquid column pressure, and if the preset condition is met, the calculated temperature, pressure, gas volume and miscible phase density are output, and if the preset condition is not met, the calculation is performed again.

2. The annular gas-liquid two-phase initial condition calculation method for transient kill fluid simulation according to claim 1, characterized in that, The wellhead parameters include the shut-in casing pressure, overflow volume and drilling fluid density.

3. The annular gas-liquid two-phase initial condition calculation method for transient kill fluid simulation according to claim 2, characterized in that, Formation pressure value : ； wherein P d0 Pc is the casing pressure, g is the acceleration of gravity, H h is the depth of the well, ρ is the density of the drilling fluid.

4. The annular gas-liquid two-phase initial condition calculation method for transient kill fluid simulation according to claim 2, characterized in that, initial trial altitude The formula for calculating the initial trial altitude is: ； wherein is the annulus cross-sectional area, V g0 is the initial spill rate.

5. The annular gas-liquid two-phase initial condition calculation method for transient kill fluid simulation according to claim 4, characterized in that, The temperature, pressure, gas volume and miscible phase density of the calculation point and the gas volume and miscible phase density in each section height are calculated, specifically as follows: The calculation formula of the temperature is: ； wherein T 0 is the ground temperature, T a is the ground temperature gradient; pressure P The formula for the calculation is: The calculation formula of the gas volume is: wherein, Z is the compressibility factor, R is the ideal gas constant, n is the number of moles of gas, M is the relative molecular weight of the gas, P b is the bottom hole pressure, Z b is the size of the natural gas compressibility factor at the bottom of the well, H s is the height of the well depth at the point of calculation, T b is the size of the temperature at the bottom of the well, n all is the number of moles of gas in the entire wellbore; The calculation formula of the gas phase density and the liquid phase density is: wherein is the liquid phase density at standard conditions, is the pressure at standard conditions, is the gas phase sound speed; The calculation formula of the gas volume fraction and the liquid volume fraction is: The calculation formula of the miscible phase density is: 。 6. The annular gas-liquid two-phase initial condition calculation method for transient kill fluid simulation according to claim 5, characterized in that, The preset condition is: If then the measurement is repeated according to the measurement procedure; If then the following is further determined: wherein Ptop is the pressure at the top of the current calculation segment; PREF is the set annulus pressure reference value; If satisfied, the height of the mixed overflow is output j If not satisfied, the height of the mixed overflow is output j- 1, and the calculated temperature, pressure, gas volume, and miscible density are output.

7. An annular gas-liquid two-phase initial condition calculation device for transient kill well simulation, characterized by, The method comprises the following steps: The parameter acquisition unit is configured to detect overflow and complete the shut-in operation, and real-time acquisition of wellhead parameters is performed; a first computing unit configured to calculate a formation pressure value from the wellhead parameters and an initial trial height ; a second computing unit configured to determine the total number of moles of gas contained within the miscible section from the formation pressure and the miscible section volume; a third calculation unit configured to set initial pressure and temperature parameters based on the total number of moles of gas and an initial trial height, starting from the bottom of the miscible section, i.e. the well bottom location solving for temperature, pressure and gas volume and miscibility density within each height of the calculation points; The result judgment and output unit is configured to compare the calculated top pressure of the miscible phase section with the sum of the measured shut-in casing pressure and the upper static liquid column pressure, and if the preset condition is met, the calculated temperature, pressure, gas volume and miscible phase density are output, and if the preset condition is not met, the measurement process is re-measured.

8. An electronic device, comprising: The method comprises the following steps: At least one processor; And a memory connected in communication with the processor; wherein the memory stores instructions executable by the processor, and the instructions are executed by the processor to enable the processor to execute the method according to any one of claims 1-6.

9. A computer-readable storage medium storing one or more programs, the one or more programs comprising instructions for: The one or more programs include computer instructions for causing a computer to execute the method according to any one of claims 1-6. The one or more programs include computer instructions for causing a computer to execute the method according to any one of claims 1-6.

Images