Full inclination natural gas-water eccentric annulus drift flow parameter measuring device and method

Abstract

The present application relates to the technical field of oil development, and particularly relates to a device and method for measuring parameters of natural gas-water eccentric annular drift flow with full inclination. Two ends of an eccentric test inner tube are respectively installed in a transparent pressure-bearing test outer tube through end face sliding eccentric adjustment devices, a series type gas-liquid uniform distribution injection module is installed on the lower side of the transparent pressure-bearing test outer tube and is connected to the output end of a gas-liquid supply module through a pipeline, a full-inclination composite guide rail anti-vibration support module is installed on the outer side of the transparent pressure-bearing test outer tube, and a gas-liquid separation and tail gas safety treatment module is connected to the tail ends of the transparent pressure-bearing test outer tube and the eccentric test inner tube through a pipeline. The present application can form a full-inclination, repeatable and measurable natural gas-water eccentric annular two-phase flow state, reliably measure parameters such as a distribution coefficient and a drift velocity, and provide support for wellbore pressure prediction, early gas invasion identification and fine pressure control drilling in the process of natural gas drilling.

Description

Technical Field

[0001] This invention relates to the field of petroleum development technology, and in particular to a device and method for measuring parameters of eccentric annular drift flow of natural gas-water at full tilt angle. Background Technology

[0002] As global oil and gas exploration and development continues to advance into deeper water, deeper formations, and more complex geological structures, the temperature and pressure boundary conditions encountered are becoming increasingly demanding. During drilling in deep, high-pressure formations, if the bottom-hole pressure becomes unbalanced, natural gas from the formation can easily invade the wellbore, mixing with formation water or drilling fluid to form a small, confined gas-liquid two-phase flow. Due to the high compressibility of natural gas, after gas intrusion occurs, the gas volume expands uncontrollably and rapidly during the upward migration of the fluid, causing a rapid decrease in the wellbore fluid column pressure. If not intervened in time, this can easily escalate into a well kick or even a blowout, leading to a severe combustion and explosion accident, causing devastating damage to wellbore integrity, surface facilities, and human lives. Accurately obtaining the parameters of the natural gas-water two-phase drift flow within the wellbore, especially key parameters such as the distribution coefficient and drift velocity, can significantly improve the accuracy and reliability of wellbore pressure dynamic prediction, early gas intrusion identification, precise pressure-controlled drilling, and blowout management. Therefore, research on the evolution law of natural gas-water two-phase drift flow under complex working conditions has become an urgent need to break through the bottleneck of multiphase flow calculation, effectively prevent major downhole accidents, and ensure the safe and efficient advancement of drilling projects.

[0003] However, existing experimental studies and testing equipment for gas-liquid two-phase drift flow are mostly conducted on conventional gases such as air and systems involving water or oil. Natural gas intruding into formations is essentially a complex multi-component mixture dominated by methane, exhibiting extremely high compressibility and more complex physical properties such as density and viscosity. As the fluid migrates towards the wellhead and the pressure of the overlying liquid column decreases, the mixed gas phase undergoes rapid expansion, easily leading to risks such as gas phase inrush, violent slippage, and transient flow pattern changes within the eccentrically confined annulus. This makes it difficult to reveal the true transport patterns of gas-liquid two-phase flow under natural gas intrusion conditions using empirical relationships and experimental equipment based on conventional air systems. Meanwhile, existing multiphase flow testing devices generally suffer from structural defects: First, existing devices are mostly limited to conventional straight circular pipes or ideal concentric annular models, rarely achieving effective simulation of real wellbore drill string eccentricity conditions; second, the full-angle adjustment mechanism is often structurally simple and lacks vibration-damping and stabilizing support for the experimental pipeline. When simulating gas-liquid two-phase flow, long-distance test pipe sections are prone to severe vibration, making it difficult to ensure the stability of the wellbore attitude. In summary, existing conventional gas-liquid two-phase flow experimental devices struggle to construct realistic flow boundaries in natural gas-water eccentric annular structures, achieve stable support for test sections under full-angle conditions, and lack a comprehensive exhaust gas safety treatment mechanism, thus making it difficult to accurately determine key parameters of natural gas-water two-phase drift flow.

[0004] Therefore, it is necessary to develop a device and method for measuring the parameters of the eccentric annular drift flow of natural gas-water at full tilt angle. This device and method are applicable to full tilt angle conditions, can achieve eccentric boundary adjustment without destroying the integrity of the annular flow channel, and can realize the measurement of the parameters of the two-phase drift flow of natural gas-water and the safe treatment of exhaust gas. This has important theoretical significance and engineering value. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned deficiencies in existing technologies by providing a device and method for measuring parameters of natural gas-water eccentric annular drift flow at a full tilt angle. This invention constructs a measurement device composed of a gas-liquid supply module, a series-connected gas-liquid uniform injection module, an end-face sliding eccentric adjustment module, a full tilt angle composite guide rail vibration damping support module, a parameter measurement and data acquisition module, and a gas-liquid separation and exhaust gas safety treatment module. Through the synergy of these modules, this invention can establish a repeatable and measurable two-phase flow state of natural gas-water eccentric annular flow at an experimental scale, enabling reliable determination of key drift flow parameters such as distribution coefficient and drift velocity. This provides an experimental platform for research on wellbore pressure prediction, early gas intrusion identification, and fine-controlled pressure drilling during natural gas drilling.

[0006] The present invention discloses a full-tilt-angle natural gas-water eccentric annular drift flow parameter measurement device. The technical solution includes a gas-liquid supply module, a transparent pressure-bearing test outer tube, and a parameter measurement and data acquisition module. It further includes an eccentric test inner tube, a series-connected gas-liquid uniform injection module, an end-face sliding eccentric adjustment device, a full-tilt-angle composite guide rail vibration-damping support module, and a gas-liquid separation and tail gas safety treatment module. The two ends of the eccentric test inner tube are respectively installed inside the transparent pressure-bearing test outer tube via the end-face sliding eccentric adjustment device, forming an adjustable eccentric structure. A series-connected gas-liquid uniform injection module is installed on the lower side of the transparent pressure-bearing test outer tube and connected to the output end of the gas-liquid supply module via a pipeline, used to construct a stable two-phase flow boundary at the inlet of the transparent pressure-bearing test outer tube. A full-tilt-angle composite guide rail vibration-damping support module is installed on the outer side of the transparent pressure-bearing test outer tube to ensure the attitude stability of the test section under different tilt angle conditions. The tail ends of the transparent pressure-bearing test outer tube and the eccentric test inner tube are connected to the gas-liquid separation and tail gas safety treatment module via pipelines, enabling the parameter measurement process to operate in a safe closed-loop environment. The aforementioned end-face sliding eccentric adjustment device includes a limiting locking bolt assembly, an integrated eccentric adjustment slide plate, an end-face sealing gasket, and an eccentric adjustment guide rail. The outer end of the integrated eccentric adjustment slide plate is connected to the lower end base of the transparent pressure-bearing test outer tube via the limiting locking bolt assembly. An eccentric adjustment guide rail is provided on the lower end base. An end-face sealing gasket is provided between the integrated eccentric adjustment slide plate and the lower end base of the transparent pressure-bearing test outer tube. The upper surface of the integrated eccentric adjustment slide plate is connected to the bottom end of the eccentric test inner tube. By moving the position of the integrated eccentric adjustment slide plate and locking it via the limiting locking bolt assembly, the eccentric test inner tube is positioned at an eccentric position within the inner cavity of the transparent pressure-bearing test outer tube.

[0007] Preferably, the above-mentioned series gas-liquid uniform injection module includes a liquid phase circumferential injection port, a gas phase circumferential injection port, and a gas phase oblique injection micropore. The lower side of the transparent pressure-bearing test outer tube is provided with a liquid phase circumferential injection port and a gas phase circumferential injection port, and a plurality of gas phase oblique injection micropores are arranged inside the gas phase circumferential injection port.

[0008] Preferably, the aforementioned full-tilt composite guide rail vibration damping support module includes a horizontal tilt angle adjusting guide rail, a horizontal tilt angle adjusting slider, a main frame, a first longitudinal support body, a longitudinal tilt angle adjusting guide rail, a longitudinal tilt angle adjusting slider, a second longitudinal support body, and a longitudinal stabilizing support guide rail. The horizontal tilt angle adjusting guide rail is installed horizontally on the main frame, and the first and second longitudinal supports are installed longitudinally. The longitudinal tilt angle adjusting guide rail is installed on the first longitudinal support body, and the longitudinal stabilizing support guide rail is installed on the second longitudinal support body. A sliding eccentric adjustment device at the bottom end is movably connected to the horizontal tilt angle adjusting slider, which moves along the horizontal tilt angle adjusting guide rail. A sliding eccentric adjustment device at the top end is movably connected to the longitudinal tilt angle adjusting slider, which moves along the longitudinal tilt angle adjusting guide rail, thereby achieving full-tilt angle adjustment of the transparent pressure-bearing test outer tube.

[0009] Preferably, an auxiliary fixing device is installed in the middle of the aforementioned transparent pressure-bearing test outer tube. The auxiliary fixing device is movably connected to the first stable telescopic support rod and the second stable telescopic support rod, respectively. The lower end of the first stable telescopic support rod is connected to a horizontal stable support slider, which is installed on a horizontal stable support guide rail. The right end of the second stable telescopic support rod is connected to a longitudinal stable support slider, which is installed on a longitudinal stable support guide rail. The horizontal stable support guide rail is installed on the horizontal section of the main frame, and the longitudinal stable support guide rail is installed on the left side of the second longitudinal support body.

[0010] Preferably, the above-mentioned gas-liquid separation and exhaust gas safety treatment module includes a gas-liquid separator, a liquid level sensor, a safety valve, a second gas flow meter, a second pressure sensor, an explosion-proof fan, and an exhaust gas catalytic oxidation device. A liquid level sensor is installed on one side of the gas-liquid separator. The inlet of the gas-liquid separator is connected to the mixed fluid outlet at the outlet end of the transparent pressure-bearing test outer pipe through a pipeline. The upper outlet of the gas-liquid separator is connected to the exhaust gas catalytic oxidation device through a pipeline, a safety valve, a second gas flow meter, a second pressure sensor, and an explosion-proof fan. The lower outlet of the gas-liquid separator is connected to a water storage tank through a pipeline.

[0011] Preferably, the gas-liquid supply module includes a natural gas cylinder, a nitrogen cylinder, a pressure reducing and stabilizing valve, a first pressure sensor, a first gas flow meter, a water storage tank, a circulating water pump, and a liquid flow meter. The natural gas cylinder and the nitrogen cylinder are connected to the gas phase circumferential injection port via pipelines, the pressure reducing and stabilizing valve, the first pressure sensor, and the first gas flow meter. The water storage tank is connected to the liquid phase circumferential injection port via pipelines, the circulating water pump, and the liquid flow meter.

[0012] Preferably, the above-mentioned parameter measurement and data acquisition module includes an impedance gas content meter and a data acquisition and industrial control computer. The impedance gas content meter is installed in the middle and rear section of the transparent pressure-bearing test outer tube to acquire the transient gas content signal of the test section. The impedance gas content meter is connected to the data acquisition and industrial control computer through an electrical wire.

[0013] The measurement method of the fully inclined natural gas-water eccentric annular drift flow parameter measuring device mentioned in this invention includes the following steps: I. Wellbore Inclination Adjustment and Eccentricity Setting: First, the eccentricity of the eccentric test inner tube is adjusted to establish the eccentric annular boundary conditions corresponding to the target working condition. During adjustment, the limit locking bolt assembly in the end face sliding eccentric adjustment device is loosened first, so that the integrated eccentric adjustment slide plate slides radially under the guidance constraint of the eccentric adjustment guide slide rail, thereby causing the eccentric test inner tube to shift relative to the transparent pressure-bearing test outer tube, changing the center offset between the inner and outer tube axes, and forming an annular flow channel with a preset eccentricity. After the adjustment is in place, the position is locked by the limit locking bolt assembly, and the end sealing gasket is used to maintain the end seal. Then, the full tilt angle of the transparent pressure test outer tube is adjusted. The lower end of the transparent pressure test outer tube is connected to the horizontal tilt angle adjustment guide rail through the horizontal tilt angle adjustment slider. The middle part is supported and vibration-damping supported by the horizontal stabilizing support slider, the horizontal stabilizing support guide rail, the first stabilizing telescopic support rod, the second stabilizing telescopic support rod, the longitudinal stabilizing support slider, and the longitudinal stabilizing support guide rail. The top of the transparent pressure test outer tube is connected to the longitudinal tilt angle adjustment guide rail through the longitudinal tilt angle adjustment slider. During adjustment, the horizontal tilt adjustment slider and the longitudinal tilt adjustment slider move synchronously along the corresponding horizontal tilt adjustment guide rail and the longitudinal tilt adjustment guide rail, respectively, thereby changing the relative position of the support points at both ends of the test section. At the same time, the horizontal stabilizing support slider and the longitudinal stabilizing support slider move in coordination, and the first stabilizing telescopic support rod and the second stabilizing telescopic support rod perform length compensation and support adaptation according to the posture changes of the test section to ensure the overall stability of the test section under different tilt angle conditions. II. System safety initialization and inert gas purging and replacement: After setting the inclination angle of the transparent pressure test outer tube and the eccentricity of the eccentric test inner tube, the entire parameter measurement device is initialized with safety and purged with inert gas to remove residual air in the test pipeline and establish safe and stable initial conditions for parameter measurement. III. Natural Gas-Water Two-Phase Injection and Steady-State Flow Field Establishment: After completing the system safety initialization and inert gas purging and replacement, the nitrogen cylinder is first shut off, and the circulating water pump continues to run, so that the liquid medium is transported from the water tank, enters the measuring device through the liquid flow meter, and flows sequentially through the circumferential liquid phase uniform injection component, the eccentric annular flow channel formed by the transparent pressure-bearing test outer tube and the eccentric test inner tube, and the mixed fluid outlet, and finally enters the gas-liquid separator and flows back to the water tank, thereby establishing a stable liquid phase circulation; Based on the stable liquid phase flow, the natural gas cylinder is slowly opened, and the natural gas outlet state is adjusted through the pressure reducing and stabilizing valve. At the same time, the target flow rate of the first gas flow meter is set in the data acquisition and industrial control computer, so that the natural gas enters the measuring device through the circumferential gas phase uniform injection component. After the natural gas is introduced through the circumferential gas phase injection port, it is injected into the main liquid phase flow in the form of a dispersed microjet through the oblique gas phase injection micro-hole. The liquid phase then enters the eccentric annular flow channel through the circumferential liquid phase uniform injection component, thereby establishing a natural gas-water two-phase flow boundary at the inlet of the test section. As the natural gas and liquid phase flow together through the eccentric annular test section, under the combined action of the boundary conditions of wellbore inclination angle, eccentricity, and gas-liquid flow rate combination, a natural gas-water two-phase flow state corresponding to the preset test conditions is gradually formed in the test section. IV. Synchronous Acquisition of Drift Flow Basic Parameters and Exhaust Gas Safety Treatment: The output signals of the first pressure sensor, first gas flow meter, liquid flow meter, impedance gas holdup meter, liquid level sensor, second gas flow meter, and second pressure sensor are synchronously acquired and recorded by the data acquisition and industrial control computer to obtain the basic parameter data of the natural gas-water eccentric ring air-liquid two-phase flow under the current experimental conditions. The impedance gas holdup meter is used to continuously measure the transient gas holdup change signal of the test section, and the average gas holdup parameter of the section under the corresponding conditions is obtained by processing the signal within a preset sampling time window. During the acquisition process, the operating status of the natural gas cylinder, circulating water pump, and each flow control unit is kept stable, and the two-phase flow pattern in the current test section is observed by combining the flow state in the transparent pressure test outer pipe to ensure that the acquired data corresponds to the steady-state flow state. For different wellbore inclination angles, eccentricities, and gas-liquid flow combinations, the above synchronous acquisition process is repeated to form the experimental dataset required for subsequent distribution coefficient and drift velocity fitting. After the basic parameters of the drift flow are collected, the natural gas-water mixture at the outlet of the test section is discharged through the mixed fluid outlet and enters the gas-liquid separator. The separated liquid phase is returned to the water storage tank for continued recycling. The separated tail gas is transported to the tail gas catalytic oxidation device through the second gas flow meter, the second pressure sensor and the explosion-proof fan. The tail gas catalytic oxidation device uses a catalyst to reduce the activation energy of the oxidation reaction of combustible components, so that the tail gas undergoes an oxidation reaction under no-flame conditions and is finally converted into carbon dioxide and water, thereby reducing the risk of combustion and explosion caused by the direct emission of combustible tail gas.

[0014] Preferably, the process also includes the following: V. Fitting of distribution coefficient and drift velocity: After synchronously collecting the basic parameters of the drift flow under different wellbore inclination angles, eccentricities, and gas-liquid flow rate combinations, the distribution coefficient and drift velocity of the natural gas-water eccentric annular air-liquid two-phase drift flow were fitted based on the obtained gas phase flow rate, liquid phase flow rate, average gas content of the test section, and corresponding experimental operating parameters. Among them, the steady-state flow parameters obtained by the first gas flow meter and liquid flow meter on the inlet side were used as the main measurement basis for fitting, and the liquid phase recovery amount and tail gas flow rate after separation obtained by the liquid level sensor and the second gas flow meter were used as the verification basis to verify the steady-state consistency and material balance of the experimental data, thereby improving the reliability of the fitting results. During fitting, firstly, based on the geometric dimensions of the test section and the measured flow parameters, the annular hydraulic diameter, apparent mixing velocity, and characteristic parameters of the mixing Reynolds number are calculated using conventional methods. Then, under fixed wellbore inclination and fixed eccentricity conditions, multiple sets of steady-state experimental data are obtained under the same geometric boundary conditions by changing the gas-liquid two-phase flow combinations. Based on the fundamental drift flow equations: (1), In the formula:C 0 is the distribution coefficient, which is dimensionless; V gr The drift velocity is in m / s; E g The gas content of the cross section is dimensionless. V m The velocity of the mixed fluid is in m / s; V sg The apparent velocity of the gas is in m / s; The fundamental relationship for identifying within-group parameters is: due to the distribution coefficient in this formula... C 0 and drift speed V gr Since there are two parameters to be identified, they cannot be solved directly based on a single operating point. Instead, under conditions of fixed inclination angle and fixed eccentricity, steady-state data from multiple sets of different gas-liquid flow rate combinations are used to... V sg / E g As the dependent variable, with V m Regression is performed on the independent variable to identify the distribution coefficient under this set of working conditions. C 0 and drift speed V gr Based on this, we can determine the applicability and consistency of the data set under the drift flow model. After identifying the apparent parameters within the group, the results of all apparent parameters obtained under different dip angles, eccentricities, and flow rate combinations are summarized and analyzed. Combined with gas holdup, mixing Reynolds number, dip angle, eccentricity, and annular characteristic scales, a distribution coefficient model and a drift velocity model suitable for natural gas-water two-phase flow in a fully dipped, eccentric annulus are established. The distribution coefficient model is as follows: (2), The drift velocity model is: (3), In the formula: c 1- c 10 These are undetermined parameters, obtained by fitting experimental data, and are dimensionless. R e m The mixed Reynolds number is dimensionless; θ ε is the wellbore inclination angle, in °; ε is the eccentricity, dimensionless. g The acceleration due to gravity is m / s². 2 σ represents the surface tension of the gas-liquid mixture, in N / m; Δ ρ The density difference between the gas and liquid phases is expressed in kg / m³. 3 ; ρ l The density of the liquid phase is kg / m³. 3; D h The annular hydraulic diameter is in meters (m). After establishing the above correlation model, it is substituted into the basic relationship of drift flow to obtain the theoretical gas holdup under the corresponding working condition. The deviation between the theoretical gas holdup and the measured gas holdup is used as the objective function for optimization, and its expression is: (4), In the formula: J The objective function is dimensionless. N The total number of samples is dimensionless. W i Let be the weight coefficient of the i-th sample point, which is dimensionless; E g,i Let be the measured gas content of the i-th sample point, which is dimensionless; E g,cal,i Let be the calculated gas content of the i-th sample point, which is dimensionless; By minimizing the objective function, the undetermined parameters in the distribution coefficient model and drift velocity model are obtained. The parameter fitting method adopts the least squares method, constrained nonlinear regression method, genetic algorithm or a combination thereof. Through the above fitting process, the distribution coefficient and drift velocity calculation models of natural gas-water eccentric annular two-phase drift flow applicable to different tilt angles, different eccentricities and different gas-liquid flow rates are obtained.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention employs a circumferentially distributed gas-liquid injection structure to improve the uniformity of gas-liquid distribution in the inlet region of the test section, reduce inlet impact, and enhance the stability of the two-phase flow boundary. It utilizes an end-face sliding eccentric adjustment device to achieve inner tube offset while maintaining end sealing and annular flow channel integrity, forming annular geometric boundaries with different eccentricities. A full-angle composite guide rail vibration-damping support structure enables continuous tilt adjustment of the test section from 0° to 90°, effectively reducing swaying and vibration of long-range test sections during experiments and improving test stability and reliability under different wellbore attitudes. Simultaneously, by combining inlet gas pressure, gas-liquid flow rate, gas cut, outlet side liquid level, tail gas flow rate, and tail gas delivery pressure with synchronous monitoring, and in conjunction with tail gas catalytic oxidation treatment, safe and high-precision measurement of natural gas-water eccentric annular air-liquid two-phase drift flow parameters can be achieved. This device and method can provide a high-precision and high-reliability experimental platform for wellbore multiphase flow pressure prediction, gas intrusion identification, fine-controlled pressure drilling, and related theoretical research. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the end face sliding eccentric adjustment device; In the diagram: 1. Natural gas cylinder; 2. Nitrogen cylinder; 3. Pressure reducing and stabilizing valve; 4. First pressure sensor; 5. First gas flow meter; 6. Water storage tank; 7. Circulating water pump; 8. Liquid flow meter; 9. Circumferential liquid phase uniform injection assembly; 10. Circumferential gas phase uniform injection assembly; 11. Transparent pressure-bearing test outer tube; 12. Eccentric test inner tube; 13. Impedance type gas content meter; 14. Mixed fluid outlet; 15. End face sliding eccentric adjustment device; 16. Horizontal tilt angle adjustment guide rail; 17. Horizontal tilt angle adjustment slider; 18. Horizontal stabilizing support slider; 19. Horizontal stabilizing support guide rail. 9. First stabilizing telescopic support rod; 20. Data acquisition and industrial control computer; 21. Gas-liquid separator; 22. Liquid level sensor; 23. Safety valve; 24. Second gas flow meter; 25. Second pressure sensor; 26. Explosion-proof fan; 27. Tail gas catalytic oxidation device; 28. Main frame; 29. ​​First longitudinal support body; 30. Longitudinal tilt angle adjustment guide rail; 31. Longitudinal tilt angle adjustment slider; 32. Second longitudinal support body; 33. Longitudinal stabilizing support slider; 34. Longitudinal stabilizing support guide rail; 35. Auxiliary fixer; 36. Second stabilizing telescopic support rod; 37. Limiting locking bolt assembly 15.1, integrated eccentric adjustment slide plate 15.2, end face sealing gasket 15.3, eccentric adjustment guide slide rail 15.4, liquid phase circumferential injection port 15.5, gas phase circumferential injection port 15.6, gas phase oblique injection micropore 15.7. Detailed Implementation

[0017] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0018] Example 1, referring to Figure 1 and Figure 2 The present invention discloses a full-tilt-angle natural gas-water eccentric annular drift flow parameter measurement device, comprising a gas-liquid supply module, a transparent pressure-bearing test outer tube 11, and a parameter measurement and data acquisition module. It further includes an eccentric test inner tube 12, a series-connected gas-liquid uniform injection module, an end-face sliding eccentric adjustment device 15, a full-tilt-angle composite guide rail anti-vibration support module, and a gas-liquid separation and exhaust gas safety treatment module. The two ends of the eccentric test inner tube 12 are respectively installed inside the transparent pressure-bearing test outer tube 11 via the end-face sliding eccentric adjustment device 15, forming an adjustable eccentric structure. A series gas-liquid uniform injection module is installed on the lower side of the transparent pressure-bearing test outer tube 11 and connected to the output end of the gas-liquid supply module through a pipeline. This module is used to construct a stable two-phase flow boundary at the inlet of the transparent pressure-bearing test outer tube 11. A full-angle composite guide rail anti-vibration support module is installed on the outer side of the transparent pressure-bearing test outer tube 11 to ensure the attitude stability of the test section under different inclination conditions. A gas-liquid separation and exhaust gas safety treatment module is connected to the tail end of the transparent pressure-bearing test outer tube 11 and the eccentric test inner tube 12 through a pipeline, so that the parameter measurement process operates in a safe closed-loop environment. The aforementioned end-face sliding eccentric adjustment device 15 includes a limiting locking bolt assembly 15.1, an integrated eccentric adjustment slide plate 15.2, an end-face sealing gasket 15.3, and an eccentric adjustment guide rail 15.4. The outer end of the integrated eccentric adjustment slide plate 15.2 is connected to the lower end base of the transparent pressure-bearing test outer tube 11 through the limiting locking bolt assembly 15.1. An eccentric adjustment guide rail 15.4 is provided on the lower end base. An end-face sealing gasket 15.3 is provided between the integrated eccentric adjustment slide plate 15.2 and the lower end base of the transparent pressure-bearing test outer tube 11. The upper surface of the integrated eccentric adjustment slide plate 15.2 is connected to the bottom end of the eccentric test inner tube 12. By moving the position of the integrated eccentric adjustment slide plate 15.2 and locking it through the limiting locking bolt assembly 15.1, the eccentric test inner tube 12 is positioned eccentrically within the inner cavity of the transparent pressure-bearing test outer tube 11.

[0019] Preferably, the above-mentioned series gas-liquid uniform injection module includes a liquid phase circumferential injection port 15.5, a gas phase circumferential injection port 15.6, and a gas phase oblique injection micropore 15.7. The lower side of the transparent pressure-bearing test outer tube 11 is provided with a liquid phase circumferential injection port 15.5 and a gas phase circumferential injection port 15.6, and a plurality of gas phase oblique injection micropores 15.7 are arranged inside the gas phase circumferential injection port 15.6.

[0020] Preferably, the above-mentioned full-tilt composite guide rail vibration damping support module includes a horizontal tilt angle adjusting guide rail 16, a horizontal tilt angle adjusting slider 17, a main frame 29, a first longitudinal support 30, a longitudinal tilt angle adjusting guide rail 31, a longitudinal tilt angle adjusting slider 32, a second longitudinal support 33, and a longitudinal stabilizing support guide rail 35. The horizontal tilt angle adjusting guide rail 16 is installed in the horizontal direction of the main frame 29, and the first longitudinal support 30 and the second longitudinal support 33 are installed in the longitudinal direction. The longitudinal tilt angle adjusting guide rail 31 is installed on the first longitudinal support 30, and the longitudinal stabilizing support guide rail 35 is installed on the second longitudinal support 33. The end face sliding eccentric adjustment device 15 at the bottom end is movably connected to the horizontal tilt angle adjusting slider 17, and the horizontal tilt angle adjusting slider 17 moves along the horizontal tilt angle adjusting guide rail 16. The end face sliding eccentric adjustment device 15 at the top end is movably connected to the longitudinal tilt angle adjusting slider 32, and the longitudinal tilt angle adjusting slider 32 moves along the longitudinal tilt angle adjusting guide rail 31 to realize the full tilt angle adjustment of the transparent pressure-bearing test outer tube 11.

[0021] Preferably, an auxiliary fixing device 36 is installed in the middle of the aforementioned transparent pressure-bearing test outer tube 11. The auxiliary fixing device 36 is movably connected to the first stable telescopic support rod 20 and the second stable telescopic support rod 37. The lower end of the first stable telescopic support rod 20 is connected to a horizontal stable support slider 18, which is mounted on a horizontal stable support guide rail 19. The right end of the second stable telescopic support rod 37 is connected to a longitudinal stable support slider 34, which is mounted on a longitudinal stable support guide rail 35. The horizontal stable support guide rail 19 is installed on the horizontal section of the main frame 29, and the longitudinal stable support guide rail 35 is installed on the left side of the second longitudinal support body 33.

[0022] Preferably, the above-mentioned gas-liquid separation and exhaust gas safety treatment module includes a gas-liquid separator 22, a liquid level sensor 23, a safety valve 24, a second gas flow meter 25, a second pressure sensor 26, an explosion-proof fan 27, and an exhaust gas catalytic oxidation device 28. A liquid level sensor 23 is installed on one side of the gas-liquid separator 22. The inlet of the gas-liquid separator 22 is connected to the mixed fluid outlet 14 at the outlet end of the transparent pressure-bearing test outer pipe 11 through a pipeline. The upper outlet of the gas-liquid separator 22 is connected to the exhaust gas catalytic oxidation device 28 through a pipeline, the safety valve 24, the second gas flow meter 25, the second pressure sensor 26, and the explosion-proof fan 27. The lower outlet of the gas-liquid separator 22 is connected to the water storage tank 6 through a pipeline.

[0023] Preferably, the gas-liquid supply module includes a natural gas cylinder 1, a nitrogen cylinder 2, a pressure reducing and stabilizing valve 3, a first pressure sensor 4, a first gas flow meter 5, a water storage tank 6, a circulating water pump 7, and a liquid flow meter 8. The natural gas cylinder 1 and the nitrogen cylinder 2 are connected to the gas phase circumferential injection port 15.6 via pipelines, the pressure reducing and stabilizing valve 3, the first pressure sensor 4, and the first gas flow meter 5. The water storage tank 6 is connected to the liquid phase circumferential injection port 15.5 via pipelines, the circulating water pump 7, and the liquid flow meter 8.

[0024] Preferably, the above-mentioned parameter measurement and data acquisition module includes an impedance gas content meter 13 and a data acquisition and industrial control computer 21. The impedance gas content meter 13 is installed in the middle and rear section of the transparent pressure-bearing test outer tube 11 to acquire the transient gas content signal of the test section. The impedance gas content meter 13 is connected to the data acquisition and industrial control computer 21 through an electrical wire.

[0025] The measurement method of the fully inclined natural gas-water eccentric annular drift flow parameter measuring device mentioned in this invention includes the following steps: I. Wellbore Inclination Adjustment and Eccentricity Setting: First, the eccentricity of the eccentric test inner tube 12 is adjusted to establish the eccentric annular boundary conditions corresponding to the target working condition. During adjustment, the limiting locking bolt assembly 15.1 in the end face sliding eccentric adjustment device 15 is loosened first, so that the integrated eccentric adjustment slide plate 15.2 slides radially under the guidance and constraint of the eccentric adjustment guide slide rail 15.4, thereby causing the eccentric test inner tube 12 to shift relative to the transparent pressure-bearing test outer tube 11, changing the center offset between the inner and outer tube axes, and forming an annular flow channel with a preset eccentricity. After the adjustment is in place, the position is locked by the limiting locking bolt assembly 15.1, and the end sealing gasket 15.3 keeps the end sealed. Then, the full tilt angle of the transparent pressure test outer tube 11 is adjusted. The lower end of the transparent pressure test outer tube 11 is connected to the horizontal tilt angle adjustment guide rail 16 through the horizontal tilt angle adjustment slider 17. The middle part is supported and vibration-damping supported by the horizontal stabilizing support slider 18, the horizontal stabilizing support guide rail 19, the first stabilizing telescopic support rod 20, the second stabilizing telescopic support rod 37, the longitudinal stabilizing support slider 34, and the longitudinal stabilizing support guide rail 35. The top of the transparent pressure test outer tube 11 is connected to the longitudinal tilt angle adjustment guide rail 31 through the longitudinal tilt angle adjustment slider 32. During adjustment, the horizontal tilt angle adjustment slider 17 and the longitudinal tilt angle adjustment slider 32 move synchronously along the corresponding horizontal tilt angle adjustment guide rail 16 and longitudinal tilt angle adjustment guide rail 31, respectively, thereby changing the relative positions of the support points at both ends of the test section. At the same time, the horizontal stabilizing support slider 18 and the longitudinal stabilizing support slider 34 move in coordination, and the first stabilizing telescopic support rod 20 and the second stabilizing telescopic support rod 37 perform length compensation and support adaptation according to the changes in the posture of the test section, so as to ensure the overall stability of the test section under different tilt angle conditions. II. System safety initialization and inert gas purging and replacement: After setting the inclination angle of the transparent pressure-bearing test outer tube 11 and the eccentricity of the eccentric test inner tube 12, the entire parameter measurement device is initialized with safety and purged with inert gas to remove residual air in the test pipeline and establish safe and stable initial conditions for parameter measurement. III. Natural Gas-Water Two-Phase Injection and Steady-State Flow Field Establishment: After completing the system safety initialization and inert gas purging and replacement, first close the nitrogen cylinder 2, keep the circulating water pump 7 running, so that the liquid medium is transported by the water storage tank 6, enters the measuring device through the liquid flow meter 8, and flows sequentially through the circumferential liquid phase uniform injection component 9, the eccentric annular flow channel formed by the transparent pressure-bearing test outer tube 11 and the eccentric test inner tube 12, and the mixed fluid outlet 14, and finally enters the gas-liquid separator 22 and flows back to the water storage tank 6, thereby establishing a stable liquid phase circulation; Based on the stable liquid phase flow, the natural gas cylinder 1 is slowly opened, and the natural gas outlet state is adjusted by the pressure reducing and stabilizing valve 3. At the same time, the target flow rate of the first gas flow meter 5 is set in the data acquisition and industrial control computer 21, so that the natural gas enters the measuring device through the circumferential gas phase uniform injection component 10. After the natural gas is introduced through the circumferential gas phase injection port 15.6, it is injected into the main liquid phase flow in the form of a dispersed microjet through the oblique gas injection micro-hole 15.7. The liquid phase enters the eccentric annular flow channel through the circumferential liquid phase uniform injection component 9, thereby establishing a natural gas-water two-phase flow boundary at the inlet of the test section. As the natural gas and liquid phase flow together through the eccentric annular test section, under the combined action of the boundary conditions of wellbore inclination angle, eccentricity and gas-liquid flow rate combination, a natural gas-water two-phase flow state corresponding to the preset test conditions is gradually formed in the test section. IV. Synchronous Acquisition of Drift Flow Basic Parameters and Exhaust Gas Safety Treatment: The data acquisition and industrial control computer 21 synchronously acquires and records the output signals of the first pressure sensor 4, the first gas flow meter 5, the liquid flow meter 8, the impedance gas content meter 13, the liquid level sensor 23, the second gas flow meter 25, and the second pressure sensor 26, thereby obtaining the basic parameter data of the natural gas-water eccentric ring air-liquid two-phase flow under the current experimental conditions. The impedance gas content meter 13 is used to continuously measure the transient gas content change signal of the test section, and by processing the signal within a preset sampling time window, the average gas content parameter of the section under the corresponding conditions is obtained. During the acquisition process, the natural gas cylinder 1, the circulating water pump 7, and each flow control unit are kept in stable operating condition, and the two-phase flow pattern in the current test section is observed in conjunction with the flow state in the transparent pressure-bearing test outer pipe 11 to ensure that the acquired data corresponds to the steady-state flow state. For different wellbore inclination angles, eccentricities, and gas-liquid flow combination conditions, the above synchronous acquisition process is repeated to form the experimental dataset required for subsequent distribution coefficient and drift velocity fitting. After the basic parameters of the drift flow are collected, the natural gas-water mixture at the outlet of the test section is discharged through the mixed fluid outlet 14 and enters the gas-liquid separator 22. The separated liquid phase is returned to the water storage tank 6 for continued recycling. The separated tail gas is transported to the tail gas catalytic oxidation device 28 through the second gas flow meter 25, the second pressure sensor 26 and the explosion-proof fan 27. The tail gas catalytic oxidation device 28 uses a catalyst to reduce the activation energy of the oxidation reaction of combustible components, so that the tail gas undergoes an oxidation reaction under no-flame conditions and is finally converted into carbon dioxide and water, thereby reducing the risk of combustion and explosion caused by the direct emission of combustible tail gas.

[0026] Example 2, the measurement method of the full-angle natural gas-water eccentric annular drift flow parameter measuring device mentioned in this invention, differs from Example 1 in that it further includes the following process: V. Fitting of distribution coefficient and drift velocity: After synchronously collecting the basic parameters of the drift flow under different wellbore inclination angles, eccentricities, and gas-liquid flow rate combinations, the distribution coefficient and drift velocity of the natural gas-water eccentric annular air-liquid two-phase drift flow are fitted based on the obtained gas phase flow rate, liquid phase flow rate, average gas content of the test section, and corresponding experimental operating parameters. Among them, the steady-state flow parameters obtained by the first gas flow meter 5 and the liquid flow meter 8 on the inlet side are used as the main measurement basis for fitting, and the liquid phase recovery amount and tail gas flow rate after separation obtained by the liquid level sensor 23 and the second gas flow meter 25 are used as the verification basis to verify the steady-state consistency and material balance of the experimental data, thereby improving the reliability of the fitting results. During fitting, firstly, based on the geometric dimensions of the test section and the measured flow parameters, the annular hydraulic diameter, apparent mixing velocity, and characteristic parameters of the mixing Reynolds number are calculated using conventional methods. Then, under fixed wellbore inclination and fixed eccentricity conditions, multiple sets of steady-state experimental data are obtained under the same geometric boundary conditions by changing the gas-liquid two-phase flow combinations. Based on the fundamental drift flow equations: (1), In the formula: C 0 is the distribution coefficient, which is dimensionless; V gr The drift velocity is in m / s; E g The gas content of the cross section is dimensionless. V m The velocity of the mixed fluid is in m / s; V sg The apparent velocity of the gas is in m / s; The fundamental relationship for identifying within-group parameters is: due to the distribution coefficient in this formula... C 0 and drift speed V gr Since there are two parameters to be identified, they cannot be solved directly based on a single operating point. Instead, under conditions of fixed inclination angle and fixed eccentricity, steady-state data from multiple sets of different gas-liquid flow rate combinations are used to... V sg / E g As the dependent variable, with V m Regression is performed on the independent variable to identify the distribution coefficient under this set of working conditions. C 0 and drift speed V gr Based on this, we can determine the applicability and consistency of the data set under the drift flow model. After identifying the apparent parameters within the group, the results of all apparent parameters obtained under different dip angles, eccentricities, and flow rate combinations are summarized and analyzed. Combined with gas holdup, mixing Reynolds number, dip angle, eccentricity, and annular characteristic scales, a distribution coefficient model and a drift velocity model suitable for natural gas-water two-phase flow in a fully dipped, eccentric annulus are established. The distribution coefficient model is as follows: (2), The drift velocity model is: (3), In the formula: c 1- c 10 These are undetermined parameters, obtained by fitting experimental data, and are dimensionless. R e m ε is the mixed Reynolds number, dimensionless; θ is the wellbore inclination angle, °; ε is the eccentricity, dimensionless. g The acceleration due to gravity is m / s². 2 σ represents the surface tension of the gas-liquid mixture, in N / m; Δ ρ The density difference between the gas and liquid phases is expressed in kg / m³. 3 ; ρ l The density of the liquid phase is kg / m³. 3 ; D h The annular hydraulic diameter is in meters (m). After establishing the above correlation model, it is substituted into the basic relationship of drift flow to obtain the theoretical gas holdup under the corresponding working condition. The deviation between the theoretical gas holdup and the measured gas holdup is used as the objective function for optimization, and its expression is: (4), In the formula: J The objective function is dimensionless. N The total number of samples is dimensionless. W i Let be the weight coefficient of the i-th sample point, which is dimensionless; E g,i Let be the measured gas content of the i-th sample point, which is dimensionless; E g,cal,i Let be the calculated gas content of the i-th sample point, which is dimensionless; By minimizing the objective function, the undetermined parameters in the distribution coefficient model and drift velocity model are obtained. The parameter fitting method adopts the least squares method, constrained nonlinear regression method, genetic algorithm or a combination thereof. Through the above fitting process, the distribution coefficient and drift velocity calculation models of natural gas-water eccentric annular two-phase drift flow applicable to different tilt angles, different eccentricities and different gas-liquid flow rates are obtained.

[0027] The above description is merely a partial preferred embodiment of the present invention. Any person skilled in the art can modify the above-described technical solutions or modify them into equivalent technical solutions. Therefore, any simple modifications or equivalent transformations made based on the technical solutions of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A parameter measurement device for eccentric annular drift flow of natural gas-water at full tilt angle, comprising a gas-liquid supply module, a transparent pressure-bearing test outer pipe (11), and a parameter measurement and data acquisition module, characterized in that: It also includes an eccentric test inner tube (12), a series gas-liquid uniform injection module, an end-face sliding eccentric adjustment device (15), a full-angle composite guide rail anti-vibration support module, and a gas-liquid separation and tail gas safety treatment module. The two ends of the eccentric test inner tube (12) are respectively installed in the transparent pressure-bearing test outer tube (11) through the end-face sliding eccentric adjustment device (15) to form an adjustable eccentric structure. The series gas-liquid uniform injection module is installed on the lower side of the transparent pressure-bearing test outer tube (11) and connected to the output end of the gas-liquid supply module through a pipeline to build a stable two-phase flow boundary at the inlet of the transparent pressure-bearing test outer tube (11). The full-angle composite guide rail anti-vibration support module is installed on the outside of the transparent pressure-bearing test outer tube (11) to ensure the attitude stability of the test section under different tilt angle conditions. The gas-liquid separation and tail gas safety treatment module is connected to the tail ends of the transparent pressure-bearing test outer tube (11) and the eccentric test inner tube (12) through a pipeline to make the parameter measurement process run in a safe closed-loop environment. The end face sliding eccentric adjustment device (15) includes a limiting locking bolt assembly (15.1), an integrated eccentric adjustment slide plate (15.2), an end face sealing gasket (15.3), and an eccentric adjustment guide rail (15.4). The outer end of the integrated eccentric adjustment slide plate (15.2) is connected to the lower end base of the transparent pressure-bearing test outer tube (11) through the limiting locking bolt assembly (15.1). An eccentric adjustment guide rail (15.4) is provided on the lower end base. An end face sealing gasket (15.3) is provided between the eccentric adjustment slide plate (15.2) and the lower end base of the transparent pressure test outer tube (11). The upper surface of the integrated eccentric adjustment slide plate (15.2) is connected to the bottom end of the eccentric test inner tube (12). By moving the position of the integrated eccentric adjustment slide plate (15.2) and locking it by the limit locking bolt assembly (15.1), the eccentric test inner tube (12) is located at the eccentric position of the inner cavity of the transparent pressure test outer tube (11). The series-connected gas-liquid uniform distribution injection module includes a liquid phase circumferential injection port (15.5), a gas phase circumferential injection port (15.6), and a gas phase oblique injection micro-hole (15.7). The lower side of the transparent pressure-bearing test outer tube (11) is provided with a liquid phase circumferential injection port (15.5) and a gas phase circumferential injection port (15.6). Multiple gas phase oblique injection micro-holes (15.7) are arranged inside the gas phase circumferential injection port (15.6).

2. The full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 1, characterized in that: The full-tilt composite guide rail vibration damping support module includes a horizontal tilt angle adjusting guide rail (16), a horizontal tilt angle adjusting slider (17), a main frame (29), a first longitudinal support (30), a longitudinal tilt angle adjusting guide rail (31), a longitudinal tilt angle adjusting slider (32), a second longitudinal support (33), and a longitudinal stabilizing support guide rail (35). The horizontal tilt angle adjusting guide rail (16) is installed in the horizontal direction of the main frame (29), and the first longitudinal support (30) and the second longitudinal support (33) are installed in the longitudinal direction. The longitudinal tilt angle is installed on the first longitudinal support (30). Adjusting guide rail (31), longitudinal stable support guide rail (35) is installed on the second longitudinal support body (33); the end face sliding eccentric adjustment device (15) at the bottom end is movably connected to the horizontal tilt angle adjustment slider (17), and the horizontal tilt angle adjustment slider (17) moves along the horizontal tilt angle adjustment guide rail (16); the end face sliding eccentric adjustment device (15) at the top end is movably connected to the longitudinal tilt angle adjustment slider (32), and the longitudinal tilt angle adjustment slider (32) moves along the longitudinal tilt angle adjustment guide rail (31) to realize the full tilt angle adjustment of the transparent pressure bearing test outer tube (11).

3. The full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 2, characterized in that: An auxiliary fixing device (36) is installed in the middle of the transparent pressure-bearing test outer tube (11). The auxiliary fixing device (36) is movably connected to the first stable telescopic support rod (20) and the second stable telescopic support rod (37). The lower end of the first stable telescopic support rod (20) is connected to a horizontal stable support slider (18), which is installed on a horizontal stable support guide rail (19). The right end of the second stable telescopic support rod (37) is connected to a longitudinal stable support slider (34), which is installed on a longitudinal stable support guide rail (35). The horizontal stable support guide rail (19) is installed on the horizontal section of the main frame (29), and the longitudinal stable support guide rail (35) is installed on the left side of the second longitudinal support body (33).

4. The full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 3, characterized in that: The gas-liquid separation and exhaust gas safety treatment module includes a gas-liquid separator (22), a liquid level sensor (23), a safety valve (24), a second gas flow meter (25), a second pressure sensor (26), an explosion-proof fan (27), and an exhaust gas catalytic oxidation device (28). A liquid level sensor (23) is installed on one side of the gas-liquid separator (22). The inlet of the gas-liquid separator (22) is connected to the mixed fluid outlet (14) at the outlet end of the transparent pressure test outer pipe (11) through a pipeline. The upper outlet of the gas-liquid separator (22) is connected to the exhaust gas catalytic oxidation device (28) through a pipeline, a safety valve (24), a second gas flow meter (25), a second pressure sensor (26), and an explosion-proof fan (27). The lower outlet of the gas-liquid separator (22) is connected to a water storage tank (6) through a pipeline.

5. The full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 4, characterized in that: The gas-liquid supply module includes a natural gas cylinder (1), a nitrogen cylinder (2), a pressure reducing valve (3), a first pressure sensor (4), a first gas flow meter (5), a water storage tank (6), a circulating water pump (7), and a liquid flow meter (8). The natural gas cylinder (1) and the nitrogen cylinder (2) are connected to the gas phase circumferential injection port (15.6) through pipelines, the pressure reducing valve (3), the first pressure sensor (4), and the first gas flow meter (5). The water storage tank (6) is connected to the liquid phase circumferential injection port (15.5) through pipelines, the circulating water pump (7), and the liquid flow meter (8).

6. The full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 5, characterized in that: The parameter measurement and data acquisition module includes an impedance gas content meter (13) and a data acquisition and industrial control computer (21). The impedance gas content meter (13) is installed in the middle and rear section of the transparent pressure test outer tube (11) to obtain the transient gas content signal of the test section. The impedance gas content meter (13) is connected to the data acquisition and industrial control computer (21) through an electrical wire.

7. A measurement method using the full-angle natural gas-water eccentric annular drift flow parameter measuring device as described in claim 6, characterized in that... Includes the following steps: I. Wellbore Inclination Adjustment and Eccentricity Setting: First, the eccentricity of the eccentric test inner tube (12) is adjusted to establish the eccentric annular boundary condition corresponding to the target working condition. During adjustment, the limit locking bolt assembly (15.1) in the end face sliding eccentric adjustment device (15) is loosened first, so that the integrated eccentric adjustment slide plate (15.2) slides radially under the guidance constraint of the eccentric adjustment guide slide rail (15.4), thereby causing the eccentric test inner tube (12) to shift relative to the transparent pressure test outer tube (11), changing the center offset between the inner and outer tube axes, and forming an annular flow channel with a preset eccentricity. After adjustment, the position is locked by the limit locking bolt assembly (15.1), and the end is sealed by the end face sealing gasket (15.3). Then, the full tilt angle of the transparent pressure test outer tube (11) is adjusted. The lower end of the transparent pressure test outer tube (11) is connected to the horizontal tilt angle adjustment guide rail (16) through the horizontal tilt angle adjustment slider (17). The middle part is supported and vibration-damping supported by the horizontal stabilizing support slider (18), the horizontal stabilizing support guide rail (19), the first stabilizing telescopic support rod (20), the second stabilizing telescopic support rod (37), the longitudinal stabilizing support slider (34), and the longitudinal stabilizing support guide rail (35). The top of the transparent pressure test outer tube (11) is connected to the longitudinal tilt angle adjustment guide rail (31) through the longitudinal tilt angle adjustment slider (32). During adjustment, the horizontal tilt adjustment slider (17) and the longitudinal tilt adjustment slider (32) are moved synchronously along the corresponding horizontal tilt adjustment guide rail (16) and longitudinal tilt adjustment guide rail (31) respectively, thereby changing the relative position of the support points at both ends of the test section. At the same time, the horizontal stabilizing support slider (18) and the longitudinal stabilizing support slider (34) move in coordination, and the first stabilizing telescopic support rod (20) and the second stabilizing telescopic support rod (37) perform length compensation and support adaptation according to the posture change of the test section, so as to ensure the overall stability of the test section under different tilt angle conditions. II. System safety initialization and inert gas purging and replacement: After setting the inclination angle of the transparent pressure test outer tube (11) and the eccentricity of the eccentric test inner tube (12), the entire parameter measurement device is initialized with safety and purged with inert gas to remove residual air in the test pipeline and establish safe and stable initial conditions for parameter measurement. III. Natural Gas-Water Two-Phase Injection and Steady-State Flow Field Establishment: After completing the system safety initialization and inert gas purging and replacement, the nitrogen cylinder (2) is closed first, and the circulating water pump (7) continues to run, so that the liquid medium is transported from the water tank (6), enters the measuring device through the liquid flow meter (8), and flows through the circumferential liquid phase uniform injection component (9), the eccentric annular flow channel formed by the transparent pressure test outer tube (11) and the eccentric test inner tube (12) and the mixed fluid outlet (14) in sequence, and finally enters the gas-liquid separator (22) and flows back to the water tank (6), thereby establishing a stable liquid phase circulation; Based on the stable liquid phase flow, the natural gas cylinder (1) is slowly opened, and the natural gas outlet state is adjusted by the pressure reducing and stabilizing valve (3). At the same time, the target flow rate of the first gas flow meter (5) is set in the data acquisition and industrial control computer (21), so that the natural gas enters the measuring device through the circumferential gas phase uniform injection component (10). After the natural gas is introduced through the gas phase circumferential injection port (15.6), it is injected into the liquid phase mainstream in the form of dispersed micro-jet through the gas phase oblique injection micro-hole (15.7). The liquid phase enters the eccentric annular flow channel through the circumferential liquid phase uniform injection component (9), thereby establishing the natural gas-water two-phase flow boundary at the entrance of the test section. As the natural gas and liquid phase flow together through the eccentric annular test section, under the combined action of the boundary conditions of wellbore inclination angle, eccentricity and gas-liquid flow rate combination, the natural gas-water two-phase flow state corresponding to the preset test conditions is gradually formed in the test section. IV. Synchronous Acquisition of Drift Flow Basic Parameters and Exhaust Gas Safety Treatment: The output signals of the first pressure sensor (4), the first gas flow meter (5), the liquid flow meter (8), the impedance gas content meter (13), the liquid level sensor (23), the second gas flow meter (25) and the second pressure sensor (26) are synchronously collected and recorded by the data acquisition and industrial control computer (21) to obtain the basic parameter data of the natural gas-water eccentric ring air-liquid two-phase flow under the current experimental conditions. Impedance gas content meter (13) is used to continuously measure the transient gas content change signal of the test section, and the average gas content parameter of the section under the corresponding working condition is obtained by processing the signal within the preset sampling time window. During the acquisition process, the natural gas cylinder (1), circulating water pump (7) and each flow control unit are kept in stable operation. The two-phase flow pattern in the current test section is observed by combining the flow state in the transparent pressure test outer pipe (11) to ensure that the acquired data corresponds to the steady-state flow state. For different wellbore inclination angle, eccentricity and gas-liquid flow combination conditions, the above synchronous acquisition process is repeated to form the experimental dataset required for subsequent distribution coefficient and drift velocity fitting. After the basic parameters of the drift flow are collected, the natural gas-water mixture at the outlet of the test section is discharged through the mixed fluid outlet (14) and enters the gas-liquid separator (22). The separated liquid phase is returned to the water storage tank (6) for continued recycling. The separated tail gas is transported to the tail gas catalytic oxidation device (28) through the second gas flow meter (25), the second pressure sensor (26) and the explosion-proof fan (27). The tail gas catalytic oxidation device (28) uses a catalyst to reduce the activation energy of the oxidation reaction of combustible components, so that the tail gas undergoes an oxidation reaction under no-flame conditions and is eventually converted into carbon dioxide and water, thereby reducing the risk of combustion and explosion caused by direct emission of combustible tail gas.

8. The measurement method of the full-angle natural gas-water eccentric annular drift flow parameter measuring device according to claim 7, characterized in that: Also includes the following process: V. Fitting of distribution coefficient and drift velocity: After the basic parameters of the drift flow under different wellbore inclination angles, eccentricities and gas-liquid flow combinations were collected synchronously, the distribution coefficient and drift velocity of the natural gas-water eccentric annular air-liquid two-phase drift flow were fitted based on the obtained gas phase flow rate, liquid phase flow rate, average gas content of the test section and corresponding experimental operating parameters. The steady-state flow parameters obtained by the first gas flow meter (5) and liquid flow meter (8) on the inlet side were used as the main measurement basis for fitting, and the liquid phase recovery amount and tail gas flow rate obtained by the liquid level sensor (23) and the second gas flow meter (25) after separation were used as the verification basis to verify the steady-state consistency and material balance of the experimental data, thereby improving the credibility of the fitting results. During fitting, firstly, based on the geometric dimensions of the test section and the measured flow parameters, the annular hydraulic diameter, apparent mixing velocity, and characteristic parameters of the mixing Reynolds number are calculated using conventional methods. Then, under fixed wellbore inclination and fixed eccentricity conditions, multiple sets of steady-state experimental data are obtained under the same geometric boundary conditions by changing the gas-liquid two-phase flow combinations. Based on the fundamental drift flow equations: (1)， In the formula: C 0 is the distribution coefficient, which is dimensionless; V gr The drift velocity is in m / s; E g The gas content of the cross section is dimensionless. V m The velocity of the mixed fluid is in m / s; V sg The apparent velocity of the gas is in m / s; The fundamental relationship for identifying within-group parameters is: due to the distribution coefficient in this formula... C 0 and drift speed V gr Since there are two parameters to be identified, they cannot be solved directly based on a single operating point. Instead, under conditions of fixed inclination angle and fixed eccentricity, steady-state data from multiple sets of different gas-liquid flow rate combinations are used to... V sg / E g As the dependent variable, with V m Regression is performed on the independent variable to identify the distribution coefficient under this set of working conditions. C 0 and drift speed V gr Based on this, we can determine the applicability and consistency of the data set under the drift flow model. After identifying the apparent parameters within the group, the results of all apparent parameters obtained under different dip angles, eccentricities, and flow rate combinations are summarized and analyzed. Combined with gas holdup, mixing Reynolds number, dip angle, eccentricity, and annular characteristic scales, a distribution coefficient model and a drift velocity model suitable for natural gas-water two-phase flow in a fully dipped, eccentric annulus are established. The distribution coefficient model is as follows: (2)， The drift velocity model is: (3)， In the formula: c 1- c 10 These are undetermined parameters, obtained by fitting experimental data, and are dimensionless. R e m ε is the mixed Reynolds number, dimensionless; θ is the wellbore inclination angle, °; ε is the eccentricity, dimensionless. g The acceleration due to gravity is m / s². 2 σ represents the surface tension of the gas-liquid mixture, in N / m; Δ ρ The density difference between the gas and liquid phases is expressed in kg / m³. 3 ; ρ l The density of the liquid phase is kg / m³. 3 ; D h The annular hydraulic diameter is in meters (m). After establishing the correlation model, it is substituted into the basic relationship of drift flow to obtain the theoretical gas holdup under the corresponding operating conditions. The deviation between the theoretical gas holdup and the measured gas holdup is used as the objective function for optimization, and its expression is: (4)， In the formula: J The objective function is dimensionless. N The total number of samples is dimensionless. W i Let be the weight coefficient of the i-th sample point, which is dimensionless; E g,i Let be the measured gas content of the i-th sample point, which is dimensionless; E g,cal,i Let be the calculated gas content of the i-th sample point, which is dimensionless; By minimizing the objective function, the undetermined parameters in the distribution coefficient model and drift velocity model are obtained. The parameter fitting method adopts the least squares method, constrained nonlinear regression method, genetic algorithm or a combination thereof. Through the above fitting process, the distribution coefficient and drift velocity calculation models of natural gas-water eccentric annular two-phase drift flow applicable to different tilt angles, different eccentricities and different gas-liquid flow rates are obtained.

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