Multi-phase fluid metering device and method with variable flow area

Abstract

The invention provides a multiphase fluid metering device and method. The metering device comprises a drainage pipe, a rotational flow generating device, a drainage adjusting device and a drainage collecting device. The rotational flow generating device is configured to enable gas-liquid two-phase fluid in the drainage pipe to perform rotational flow by taking the axis of the drainage pipe as an axis; a fluid outlet of the drainage pipe is located in the side wall of the drainage pipe. The drainage adjusting device is configured to adjust the size of a fluid outlet of the drainage pipe; the leakage flow collecting device surrounds the leakage flow pipe; a first pressure sensor is arranged between the rotational flow generating device and the fluid outlet of the drainage pipe; and a second pressure sensor is arranged on the inner wall of the discharged flow collecting device. The metering device is small in size, compact in structure, wide in application range and capable of achieving simultaneous measurement of multi-phase fluid split-phase flow and gas and liquid phase mass holdup.

Description

Technical Field

[0001] The present invention relates to the field of multiphase fluid metering, and in particular to a device for simultaneously measuring the flow rates of oil, gas and water in a multiphase mixed pipeline and a corresponding measurement method. Background Art

[0002] Multiphase fluids are widely used in many industrial fields such as petroleum, chemical industry, energy, and power. Online measurement of multiphase fluid flow is of great significance to ensure safe and efficient production.

[0003] In the multiphase fluid transportation environment, conventional single-phase flow metering methods and devices are not applicable. Multiphase flow metering methods can be generally divided into three types according to whether they are separated and the degree of separation: separation, non-separation, and split phase separation. The complete separation method uses a three-phase separator to separate the multiphase fluid into oil phase, gas phase, and water phase, and uses a single-phase flow meter to measure the flow of each phase. The measurement is not affected by the fluctuation of the multiphase flow and has high accuracy, but the separation equipment is bulky and expensive, which greatly increases the development cost of the oil field; the non-separation multiphase flow meter realizes the three-phase measurement of oil, gas, and water without any separation of the multiphase fluid. Its technical difficulty is mainly reflected in the determination of the content of the three-phase components of oil, gas, and water and the flow rate of each phase. The non-separation metering method does not require separation equipment and has a small size, but the measurement is easily affected by fluid fluctuations and has low accuracy.

[0004] The invention patent (application number: 201010588041.9) discloses a split-phase gas-liquid two-phase fluid flowmeter, which is characterized by splitting a part of the two-phase fluid from the measured two-phase fluid, separating it into single-phase gas and single-phase liquid, measuring them respectively with single-phase flow meters, and then inferring the flow of the measured two-phase fluid based on the proportional relationship. Compared with conventional multiphase metering methods, the split-phase method requires a much smaller volume of separator than the complete separation method due to split sampling. At the same time, due to phase separation, the gas and liquid phase flow measurements are completed in a single-phase medium environment, so it has the advantages of small volume and high precision. In order to ensure the accuracy of flow measurement, there must be a stable and definite relationship between the split fluid and the measured two-phase fluid. However, multiphase fluids usually undergo phase separation when flowing through the distributor, causing the sampled fluid to lose its representativeness and increasing the measurement error.

[0005] In recent years, throttling devices such as Venturi have begun to be used in flow measurement. Traditional throttling devices obtain mass flow based on the differential pressure-flow relationship, but they are only applicable to single-phase gas or liquid. For multiphase fluids, due to the existence of two parameters, total mass flow and gas phase mass content, a single differential pressure measurement cannot obtain two unknown parameters at the same time, nor can it obtain the oil, gas, and water phase flow. Summary of the invention

[0006] In order to overcome the defects of the prior art, the present disclosure proposes a variable flow area multiphase fluid metering device and method. The components of the device can be disassembled and assembled, and can be combined according to the size of the multiphase fluid flow to be measured. It has the advantages of wide measurement range, high measurement accuracy, simple operation, low cost, and no influence from flow pattern changes, and realizes continuous metering, which is particularly suitable for the development of offshore oil and gas fields.

[0007] The present invention discloses a multiphase fluid metering device, which is not affected by upstream and downstream flow states and flow patterns, has the advantages of small size, compact structure, adjustable distribution ratio, etc., and can adapt to a wider range of gas-liquid flow changes.

[0008] The present disclosure provides a multiphase fluid metering device, the metering device comprising: a leakage pipe, a swirl generating device, a leakage regulating device and a leakage collecting device;

[0009] The swirl generating device is configured to swirl the multiphase fluid in the leakage pipe about the axis of the leakage pipe;

[0010] The fluid outlet of the drainage pipe is located on the side wall of the drainage pipe;

[0011] The leakage flow regulating device is configured to adjust the size of the fluid outlet of the leakage pipe;

[0012] The leakage flow collection device surrounds the leakage flow pipe;

[0013] A first pressure sensor is provided between the swirl generating device and the fluid outlet of the drain pipe;

[0014] A second pressure sensor is arranged on the inner wall of the leakage collection device.

[0015] In one embodiment provided in the present application, the fluid outlet is a narrow slit structure penetrating the tube wall, and the multiple fluid outlets 9 have exactly the same size, are located on the same plane perpendicular to the central axis of the leakage pipe, and are evenly arranged along the circumference of the leakage pipe.

[0016] In an embodiment provided in the present application, the arrangement direction of the fluid outlet is the same as the flow direction of the liquid in the multiphase fluid metering device.

[0017] In one embodiment provided by the present disclosure, the swirl generating device is tubular and connected in series with the drain pipe, and the two have the same inner diameter; the drain pipe inlet is connected to the swirl generating device outlet, and the other end of the drain pipe is closed, so that the fluid flows out from the fluid outlet. A cyclone is arranged inside the swirl generating device.

[0018] In one embodiment provided in the present disclosure, the cyclone is composed of spiral blades and a central axis, and the outer edge of the spiral blades is tightly fitted with the inner wall of the cyclone generating device, so that the liquid flowing through the cyclone rotates around the central axis, so that the liquid in the gas-liquid two phases is closer to the inner wall of the cyclone generating device, and the gas is closer to the central axis.

[0019] In an embodiment provided by the present disclosure, the first pressure sensor is disposed on an inner wall of a tube between the cyclone and the drain pipe.

[0020] In one embodiment provided by the present disclosure, the first pressure sensor is disposed on the inner wall of the tube of the swirl generating device;

[0021] The position of the first pressure sensor is: in the direction of the cyclone toward the discharge pipe, starting from the point where the cyclone contacts the inner wall of the tube of the cyclone generating device, at a distance of (1 / 8 to 1 / 4) R;

[0022] The R is the inner diameter of the swirl generating device.

[0023] The leakage flow collection device is a cylindrical structure, the inner diameter of the leakage flow collection device is larger than the outer diameter of the swirl flow generating device, and the inlet end of the leakage flow collection device is connected to the outlet end of the swirl flow generating device through a flange. The multiphase fluid metering device also includes an outlet pipe, the inlet of the outlet pipe is connected to the outlet of the leakage flow collection device. The outlet pipe is installed on the outlet end surface of the leakage flow collection device.

[0024] In one embodiment provided by the present disclosure, the second pressure sensor is disposed on the inner wall of the tube of the leakage collection device;

[0025] The position of the second pressure sensor is: in the direction of the cyclone toward the leakage pipe, from the connection between the leakage flow collecting device and the cyclone generating device to any point of the tube wall of the projection of the fluid outlet of the leakage pipe on the inner wall of the tube of the leakage flow collecting device along the radial direction of the leakage pipe as a starting point, (0 to 1 / 8) r distance;

[0026] The r is the inner diameter of the leakage collection device.

[0027] In one embodiment provided in the present disclosure, the leakage regulating device is cylindrical, one end of the leakage regulating device is closed, a position indicating scale is arranged at the center of the outer bottom surface of the closed end, and the leakage regulating device is sleeved outside the leakage pipe.

[0028] In one embodiment provided by the present disclosure, the outer surface of the leakage pipe is provided with a thread, and the inner wall of the leakage regulating device is provided with an internal thread corresponding to the thread. The outer wall of the leakage regulating device is provided with an external thread, which can be coupled with a driving screw and a supporting screw. A supporting screw and a driving screw are provided in the annular cavity formed by the outer wall of the leakage regulating device and the inner wall of the leakage collecting device. The central axis of the driving screw is connected to the driving rod, and the driving rod extends to the outside of the leakage collecting cavity. A handle is provided at the end of the driving rod, and the driving screw can be driven to rotate by turning the handle to adjust the leakage regulating device to a specified position;

[0029] In one embodiment provided in the present disclosure, a metering inlet flange is provided at the inlet end of the swirl generating device, and a metering outlet flange is provided at the end of the outlet pipe; the multiphase fluid metering device is connected to the measured gas-liquid two-phase flow pipeline through the metering inlet flange and the metering outlet flange.

[0030] In one embodiment provided by the present disclosure, the first pressure sensor can measure the upstream pressure through the connected upstream pressure point and the pressure pipe, and the second pressure sensor can measure the downstream pressure through the connected downstream pressure point and the pressure pipe.

[0031] In one embodiment provided by the present disclosure, a differential pressure sensor can be connected between the upstream pressure point and the downstream pressure point to directly test the pressure difference between the upstream pressure point and the downstream pressure point. This setting can be equivalent to a second pressure sensor.

[0032] In another aspect, the present disclosure provides a method for measuring a multiphase fluid flow rate using the multiphase fluid metering device described above, the method comprising:

[0033] By adjusting the leakage regulating device, the size of the fluid outlet of the leakage pipe is adjusted, the first position of the leakage regulating device is recorded as m, and the second position is recorded as n;

[0034] Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the first position m TP_m ;

[0035] Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the second position n TP_n ;

[0036] The value range of the first flow coefficient A is 299 to 2999. The larger the fluid outlet of the leakage pipe is, the smaller the value of the first flow coefficient A is; the larger the diameter of the leakage pipe is, the larger the value of the first flow coefficient A is;

[0037] The value range of the second flow coefficient B is 19 to 299. The larger the fluid outlet of the leakage pipe is, the smaller the value of the second flow coefficient B is; the larger the diameter of the leakage pipe is, the larger the value of the second flow coefficient B is;

[0038] The parameter ΔP TP_m , ΔP TP_n , A, B into formula (1) and formula (2), and solve the binary equations together to calculate the total mass flow rate M of the multiphase fluid TP and gas phase mass fraction X G , to measure the gas-liquid two-phase flow rate;

[0039]

[0040]

[0041] In formula (1) and formula (2), M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass holdup, dimensionless;

[0042] ΔP TP_m is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the first position m;

[0043] ΔP TP_n is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the second position n;

[0044] A m is the first flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg; B m is the second flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg;

[0045] A n is the first flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg; B n is the second flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg.

[0046] In one embodiment provided by the present disclosure, the first flow coefficient A is calculated according to formula (3); the second flow coefficient B is calculated according to formula (4);

[0047] A x =f A(x)…………………………………………(3)

[0048] f in formula (3) A A is calculated based on the position i of the discharge regulating device under single-phase liquid conditions. Li , the fitted function f A ;

[0049] The A Li The calculation method is formula (5):

[0050]

[0051] In formula (5), ΔP Li is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase liquid conditions; M Li is the mass flow rate at position i under single-phase liquid conditions;

[0052] B x =f B (x)…………………………………………(4)

[0053] f in formula (4) B is the B calculated under single-phase gas conditions according to the position i of the different leakage regulating devices. Gi , the fitted function f B ;

[0054] B Gi The calculation method is formula (6):

[0055]

[0056] In formula (6), ΔP Gi is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase gas conditions, Pa; M Gi is the flow rate at position i under single-phase gas conditions, kg / s; A Li According to formula (5), Pa 0.5 ·s / kg.

[0057] In one embodiment provided in the present disclosure, the gas phase mass flow rate M in the multiphase fluid G Calculate according to formula (7):

[0058] M G =M TP X G ……………………………………(7)

[0059] In formula (7), MG is the gas phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless.

[0060] In one embodiment provided by the present disclosure, the liquid phase mass flow rate in the multiphase fluid is calculated according to formula (8):

[0061] M L =M TP (1-X G )…………………………………………(8)

[0062] In formula (8), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless.

[0063] In one embodiment provided by the present disclosure, the oil phase flow rate in the multiphase fluid is calculated according to formula (9):

[0064] M O =M L (1-X W )=M TP (1-X G )(1-X W )………………(9)

[0065] In formula (9), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless.

[0066] In one embodiment provided by the present disclosure, the water phase flow rate in the multiphase fluid is calculated according to formula (10):

[0067] M W =M L X W =M TP (1-X G )X W …………………………(10)

[0068] In formula (10), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TPis the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless.

[0069] On the other hand, the present disclosure provides a management device for measuring multiphase fluid flow, the management device for measuring multiphase fluid flow comprising a memory, a processor, and a management program for measuring gas-liquid two-phase flow stored in the memory and executable on the processor, the management program for measuring gas-liquid two-phase flow implementing the steps of the method for measuring gas-liquid two-phase flow as described above when executed by the processor.

[0070] On the other hand, the present disclosure provides a computer-readable storage medium, on which is stored a program for a method for measuring a gas-liquid two-phase flow rate. When the program for the method for measuring a gas-liquid two-phase flow rate is executed by a processor, the steps of the method for measuring a gas-liquid two-phase flow rate as described above are implemented.

[0071] Compared with the prior art, the present invention has the following effects:

[0072] (1) The discharge area depends on the position of the discharge regulating device. The discharge ratio can be adjusted in the range of 0-100% according to the needs of the site. By changing the position of the discharge regulating device, the characteristic pressure drop under different throttling areas can be obtained, and then the simultaneous measurement of gas and liquid flow can be achieved.

[0073] (2) Under the action of the cyclone, the wavy flow, stratified flow and uneven annular flow can be rectified into annular flow with uniform liquid film thickness, effectively eliminating the influence of two-phase flow pattern fluctuations on the measurement.

[0074] (3) It has the advantages of simple structure, easy maintenance and production, low operating cost and convenient operation.

[0075] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. Other advantages of the present disclosure can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure.

[0077] Figure 1 A schematic diagram of a device provided by the present disclosure.

[0078] Figure 2 It is a schematic diagram of the swirl generating device and the discharge pipe structure.

[0079] Figure 3 for Figure 1 Schematic diagram of the AA section.

[0080] Figure 4 It is a schematic diagram of the structure of the leakage regulating device.

[0081] Figure 5 Schematic diagram of the leakage collection chamber and outlet pipe structure.

[0082] Figure 6 Schematic diagram of the cyclone structure.

[0083] Figure 7 Schematic diagram of cyclone rectification.

[0084] Figure numerals: 1. swirl generating device; 2. discharge pipe; 3. discharge regulating device; 4. discharge collecting device; 5. outlet pipe; 6. first pressure sensor; 7. second pressure sensor; 8. cyclone; 9. fluid outlet; 10. position indicating scale; 11. supporting screw; 12. driving screw; 13. driving screw center axis; 14. driving rod; 15. handle; 16. upstream pressure point; 17. downstream pressure point; 18. metering inlet flange; 19. metering outlet flange; 20. center axis; 21. spiral blade. DETAILED DESCRIPTION

[0085] The present disclosure describes multiple embodiments, but the description is exemplary rather than restrictive, and it is apparent to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present disclosure. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0086] The present disclosure includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features, and elements disclosed in the present disclosure may also be combined with any conventional features or elements to form a unique invention scheme defined by the claims. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in the present disclosure may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other limitations. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0087] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps in the specific order described. As will be appreciated by those of ordinary skill in the art, other orders of steps are also possible. Therefore, the specific order of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps performed in the order written, and those skilled in the art can easily understand that these orders can be changed and still remain within the spirit and scope of the disclosed embodiments.

[0088] like Figure 1 As shown, a multiphase fluid metering device is exemplarily provided in an embodiment of the present disclosure, and the metering device comprises: a leakage pipe 2, a swirl generating device 1, a leakage regulating device 3 and a leakage collecting device 4;

[0089] The swirl generating device 1 is configured to swirl the gas-liquid two-phase fluid in the discharge pipe 2 about the axis of the discharge pipe 2;

[0090] The fluid outlet of the drainage pipe 2 is located on the side wall of the drainage pipe 2;

[0091] The leakage adjustment device 3 is configured to adjust the size of the fluid outlet 9 of the leakage pipe 2;

[0092] The leakage collection device 4 surrounds the leakage pipe 2;

[0093] A first pressure sensor 6 is provided between the swirl generating device 1 and the fluid outlet 9 of the drain pipe 2;

[0094] A second pressure sensor 7 is arranged on the inner wall of the leakage collection device 4 .

[0095] For example, Figure 1 , Figure 3 As shown, the fluid outlet 9 is a narrow slit structure penetrating the pipe wall, and the multiple fluid outlets 9 have exactly the same size, are located on the same plane perpendicular to the central axis of the leakage pipe 2, and are evenly arranged along the circumference of the leakage pipe 2.

[0096] Exemplarily, the arrangement direction of the multiphase fluid outlet is the same as the flow direction of the multiphase fluid in the metering device.

[0097] For example, Figure 2 , Figure 3 As shown, the swirl generating device 1 is tubular and connected in series with the drain pipe 2, and the two have the same inner diameter; the inlet of the drain pipe 2 is connected to the outlet of the swirl generating device 1, and the other end of the drain pipe 2 is closed, so that the fluid flows out from the fluid outlet 9. A cyclone 8 is arranged inside the swirl generating device 1.

[0098] For example, Figure 1 , Figure 2 and Figure 6 As shown, the cyclone 8 is composed of a spiral blade 21 and a central axis 20. The outer edge of the spiral blade 21 is tightly fitted and fixed to the inner wall of the cyclone generating device 1, so that the liquid flowing through the cyclone 8 rotates around the central axis 20. Since the density of the gas phase is much smaller than the density of the liquid phase, the liquid in the gas-liquid two phases is closer to the inner wall of the cyclone generating device 1, and the gas is closer to the central axis 20. Figure 7 As shown, for a horizontal pipeline without a cyclone device, under the action of gravity, the gas-liquid distribution in the pipe cross section is obviously asymmetric, with more liquid phase at the bottom and the gas phase mainly concentrated in the upper part of the cyclone generating device 1. Figure 7 As shown, when the swirler 8 is present, the flow patterns such as stratified flow, wave flow, semi-annular flow, asymmetric annular flow, etc. are all adjusted to a uniform annular flow pattern with a consistent distribution around the tube.

[0099] For example, Figure 1 As shown, the first pressure sensor 6 (or the pressure taking point of the first pressure sensor 6 , namely the upstream pressure taking point 16 ) is arranged on the inner wall of the pipe between the cyclone 8 and the discharge pipe 2 .

[0100] Exemplarily, the first pressure sensor 6 (or the pressure point of the first pressure sensor 6, i.e., the upstream pressure point 16) is arranged on the inner wall of the tube of the swirl generating device; the position of the first pressure sensor 6 (or the pressure point of the first pressure sensor 6, i.e., the upstream pressure point 16) is: in the direction of the cyclone 8 toward the discharge pipe 2, with the point where the cyclone 8 contacts the inner wall of the tube of the swirl generating device 1 as the starting point, at a distance of (1 / 8 to 1 / 4) R;

[0101] The R is the inner diameter of the swirl generating device 1 .

[0102] like Figure 1 , Figure 2 and Figure 5 As shown, the leakage flow collection device 4 is a cylindrical structure, the inner diameter of the leakage flow collection device 4 is larger than the outer diameter of the swirl generating device 1, and the inlet end of the leakage flow collection device 4 is connected to the outlet end of the swirl generating device 1 through a flange. The multiphase fluid metering device also includes an outlet pipe 5, the inlet of the outlet pipe 5 is connected to the outlet of the leakage flow collection device. The outlet pipe 5 is installed on the outlet end face of the leakage flow collection device 4.

[0103] The second pressure sensor 7 (or the pressure point of the second pressure sensor 7, i.e. the downstream pressure point 17) is arranged on the inner wall of the pipe of the leakage collection device 4;

[0104] The position of the second pressure sensor 7 (or the pressure point of the second pressure sensor 7, i.e., the downstream pressure point 17) is: from the cyclone 8 in the direction of the leakage pipe 2, from the connection between the leakage collection device 4 and the cyclone generating device 1 to any point of the projection of the fluid outlet of the leakage pipe 2 along the radial direction of the leakage pipe 2 on the inner wall of the leakage collection device 4, (0 to 1 / 8) r distance;

[0105] The r is the inner diameter of the leakage collection device 4 .

[0106] For example, a differential pressure sensor may be connected between the upstream pressure point and the downstream pressure point to directly test the pressure difference between the upstream pressure point and the downstream pressure point. This setting may be equivalent to a second pressure sensor.

[0107] Exemplarily, the leakage regulating device 3 is cylindrical, and the leakage regulating device 3 surrounds the outer wall of the leakage pipe 2 and fits with the outer wall of the leakage pipe 2 .

[0108] For example, Figure 1 and Figure 4 As shown, one end of the leakage regulating device 3 is closed, and a position indicating scale 10 is arranged at the center of the outer bottom surface of the closed end. The leakage regulating device 3 is sleeved outside the leakage pipe 1.

[0109] For example, Figure 1 , Figure 2 and Figure 4 As shown, the outer surface of the leakage pipe 2 is provided with threads, and the inner wall of the leakage regulating device 3 is provided with internal threads corresponding to the threads.

[0110] For example, Figure 1 , Figure 2 and Figure 4As shown, the outer wall of the leakage regulating device 3 is provided with an external thread, which can be coupled with the driving screw 12 and the supporting screw 11. The driving screw 12 and the supporting screw 11 are fixed to the outer wall of the leakage collecting device 4 and will not move relative to each other as the respective screws rotate. The supporting screw 11 and the driving screw 12 are arranged in the annular cavity formed by the outer wall of the leakage regulating device 3 and the inner wall of the leakage collecting device 4. The central axis 13 of the driving screw is connected to the driving rod 14. The driving rod 14 extends to the outside of the cavity surrounded by the leakage collecting device 4 and the swirl generating device 1. The end of the driving rod 14 is provided with a handle 15. The driving rod 14 can be driven to rotate the driving screw 12 by rotating the handle 15. The leakage regulating device 3 can be driven to move forward and backward by the engagement of the driving screw 12 and the threads on the leakage regulating device 3, thereby adjusting the leakage regulating device 3 to a specified position and changing the leakage area of ​​the fluid outlet 9.

[0111] For example, Figure 1 As shown, the inlet end of the swirl generating device 1 is provided with a metering inlet flange 18, and the end of the outlet pipe 5 is provided with a metering outlet flange 19; the multiphase fluid metering device is connected to the measured gas-liquid two-phase flow pipeline through the metering inlet flange 18 and the metering outlet flange 19.

[0112] In another aspect, the present disclosure exemplarily provides a method for measuring a multiphase fluid flow rate, using the multiphase fluid metering device described above, the method comprising:

[0113] By adjusting the leakage regulating device, the size of the fluid outlet of the leakage pipe is adjusted, the first position of the leakage regulating device is recorded as m, and the second position is recorded as n;

[0114] Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the first position m TP_m ;

[0115] Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the second position n TP_n ;

[0116] The value range of the first flow coefficient A is 299 to 2999. The larger the fluid outlet of the leakage pipe is, the smaller the value of the first flow coefficient A is; the larger the diameter of the leakage pipe is, the larger the value of the first flow coefficient A is;

[0117] The value range of the second flow coefficient B is 19 to 299. The larger the fluid outlet of the leakage pipe is, the smaller the value of the second flow coefficient B is; the larger the diameter of the leakage pipe is, the larger the value of the second flow coefficient B is;

[0118] The parameter ΔP TP_m , ΔPTP_n , A, B into formula (1) and formula (2), and solve the binary equations together to calculate the total mass flow rate M of the multiphase fluid TP and gas phase mass fraction X G , to measure the gas-liquid two-phase flow rate;

[0119]

[0120]

[0121] In formula (1) and formula (2), M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass holdup, dimensionless;

[0122] ΔP TP_m is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the first position m;

[0123] ΔP TP_n is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the second position n;

[0124] A m is the first flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg; B m is the second flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg;

[0125] A n is the first flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg; B n is the second flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg.

[0126] Exemplarily, the first flow coefficient A is calculated according to formula (3); the second flow coefficient B is calculated according to formula (4);

[0127] A x =f A (x)…………………………………………(3)

[0128] f in formula (3) A A is calculated based on the position i of the discharge regulating device under single-phase liquid conditions. Li , the fitted function f A ;

[0129] The A Li The calculation method is formula (5):

[0130]

[0131] In formula (5), ΔP Li is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase liquid conditions; M Li is the mass flow rate at position i under single-phase liquid conditions;

[0132] B x =f B (x)…………………………………………(4)

[0133] f in formula (4) B is the B calculated under single-phase gas conditions according to the position i of the different leakage regulating devices. Gi , the fitted function f B ;

[0134] B Gi The calculation method is formula (6):

[0135]

[0136] In formula (6), ΔP Gi is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase gas conditions, Pa; M Gi is the flow rate at position i under single-phase gas conditions, kg / s; A Li According to formula (5), Pa 0.5 ·s / kg.

[0137] For example, the gas phase mass flow rate M in the multiphase fluid is G Calculate according to formula (7):

[0138] M G =M TP X G ……………………………………(7)

[0139] In formula (7), M G is the gas phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless.

[0140] Exemplarily, the liquid phase mass flow rate in the multiphase fluid is calculated according to formula (8):

[0141] M L =M TP (1-X G )…………………………………………(8)

[0142] In formula (8), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless.

[0143] Exemplarily, the oil phase flow rate in the multiphase fluid is calculated according to formula (9):

[0144] M O =M L (1-X W )=M TP (1-X G )(1-X W )………………(9)

[0145] In formula (9), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless.

[0146] Exemplarily, the water phase flow rate in the multiphase fluid is calculated according to formula (10):

[0147] M W =M L X W =M TP (1-X G )X W …………………………(10)

[0148] In formula (10), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless.

[0149] Illustratively, the present disclosure provides the following embodiments, which have verified the beneficial effects of the technical solutions provided by the present disclosure.

[0150] By using the above device and method, the oil, gas and water three-phase flow rates of a multiphase produced fluid in an oil well can be measured at the wellhead by adjusting the position of the leakage regulating device. TP and gas phase mass fraction X G The solution of the two-variable equation system is as follows:

[0151] Then the gas phase mass flow rate: M G =M TP X G =0.188kg / s×3.14%=0.0059kg / s; Liquid mass flow rate: M L =M TP (1-X G )=0.188kg / s×(1-3.14%)=0.182kg / s.

[0152] Combined with the measured mass moisture content X W =88.6%, calculate the oil phase and water phase flow measurement:

[0153] Oil phase mass flow rate: M O =M L (1-X W )=0.182kg / s×(1-88.6%)=0.02155kg / s;

[0154] Water phase mass flow rate: M W =M L X W =0.182kg / s×88.6%=0.16125kg / s.

[0155] The units of oil production and water production are converted into tons per day, and the three-phase mass flow rates of oil, gas and water are compared with the actual daily production flow values ​​of a single well measured by on-site separation measurement, and the measurement error is calculated. The measurement results are as follows.

[0156] Table 1 Comparison of metering effects

[0157]

[0158] It can be seen that the measurement method provided in this application has high accuracy, and the error of the calculated result compared with the actual measured value of multiphase fluid separation measurement is within 3%, which is far lower than the requirement of "Oilfield Oil and Gas Gathering and Transportation Design Code GB50350-2015" that the maximum allowable error is within 15%.

[0159] On the other hand, the present disclosure provides a management device for measuring gas-liquid two-phase flow, the management device for measuring gas-liquid two-phase flow comprising a memory, a processor, and a management program for measuring gas-liquid two-phase flow stored in the memory and executable on the processor, and the management program for measuring gas-liquid two-phase flow, when executed by the processor, implements the steps of the method for measuring gas-liquid two-phase flow as described above.

[0160] On the other hand, the present disclosure provides a computer-readable storage medium, on which is stored a program for a method for measuring a gas-liquid two-phase flow rate. When the program for the method for measuring a gas-liquid two-phase flow rate is executed by a processor, the steps of the method for measuring a gas-liquid two-phase flow rate as described above are implemented.

[0161] In summary, if Figure 1 As shown, when the gas-liquid two-phase flow passes through the device provided by the present disclosure, the effective flow area of ​​the fluid depends only on the position of the leakage adjustment device 3. By operating the handle 15, the effective length of the fluid outlet 9 of the leakage pipe 2 can be changed to change the flow area. In practical applications, the position of the leakage adjustment device 3 can be adjusted according to the size of the upstream flow rate, and the total mass flow rate of the multiphase fluid and the gas phase mass content can be measured simultaneously by measuring the differential pressure at two different positions.

[0162] The technical solution provided by the present disclosure is not affected by factors such as the gas-liquid phase flow pattern and pressure distribution in the pipeline, has a simple structure, requires little maintenance, and has wide applicability.

[0163] It will be appreciated by those skilled in the art that all or some of the steps, systems, and functional modules / units in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementations, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, it is well known to those of ordinary skill in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

Claims

1. A variable flow area multiphase fluid metering device, characterized in that: The metering device comprises: a leakage pipe, a swirl generating device, a leakage regulating device and a leakage collecting device; The swirl generating device is configured to swirl the gas-liquid two-phase fluid in the leakage pipe about the axis of the leakage pipe; The fluid outlet of the drainage pipe is located on the side wall of the drainage pipe; The leakage flow regulating device is configured to adjust the size of the fluid outlet of the leakage pipe; The leakage flow collection device surrounds the leakage flow pipe; A first pressure sensor is provided between the swirl generating device and the fluid outlet of the drain pipe; A second pressure sensor is arranged on the inner wall of the leakage collection device.

2. The multiphase fluid metering device according to claim 1, characterized in that: The swirl generating device is cylindrical and connected in series with the discharge pipe; a cyclone is arranged inside the swirl generating device.

3. The multiphase fluid metering device according to claim 2, characterized in that: The first pressure sensor is arranged on the inner wall of the tube between the cyclone and the drain pipe.

4. The multiphase fluid metering device according to claim 3, characterized in that: The first pressure sensor is arranged on the inner wall of the tube of the swirl generating device; the position of the first pressure sensor is: in the direction of the swirl device toward the discharge pipe, with the point where the swirl device contacts the inner wall of the tube of the swirl generating device as the starting point, at a distance of (1 / 8 to 1 / 4) R; The R is the inner diameter of the swirl generating device.

5. The multiphase fluid metering device according to any one of claims 1 to 4, characterized in that: The leakage regulating device is cylindrical, surrounds the outer wall of the leakage pipe, and fits with the outer wall of the leakage pipe.

6. The multiphase fluid metering device according to claim 5, characterized in that: The second pressure sensor is arranged on the inner wall of the pipe of the leakage collection device; The position of the second pressure sensor is: in the direction of the cyclone toward the leakage pipe, from the connection between the leakage flow collecting device and the cyclone generating device to any point of the tube wall of the projection of the fluid outlet of the leakage pipe on the inner wall of the tube of the leakage flow collecting device along the radial direction of the leakage pipe as a starting point, (0 to 1 / 8) r distance; The r is the inner diameter of the leakage collection device.

7. A method for measuring multiphase fluid flow, characterized in that: The multiphase fluid metering device according to any one of claims 1 to 6 is used, characterized in that the method comprises: By adjusting the leakage regulating device, the size of the fluid outlet of the leakage pipe is adjusted, the first position of the leakage regulating device is recorded as m, and the second position is recorded as n; Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the first position m TP_m ; Obtain the pressure difference ΔP between the first pressure sensor and the second pressure sensor when the leakage regulating device is at the second position n TP_n ; The value range of the first flow coefficient A is 299 to 2999. The larger the fluid outlet of the leakage pipe is, the smaller the value of the first flow coefficient A is; the larger the diameter of the leakage pipe is, the larger the value of the first flow coefficient A is; The value range of the second flow coefficient B is 19 to 299. The larger the fluid outlet of the leakage pipe is, the smaller the value of the second flow coefficient B is; the larger the diameter of the leakage pipe is, the larger the value of the second flow coefficient B is; The parameter ΔP TP_m , ΔP TP_n , A, B are substituted into formula (1) and formula (2) to calculate the total mass flow rate M of the multiphase fluid TP and gas phase mass fraction X G , gas-liquid two-phase flow can be measured; In formula (1) and formula (2), M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass holdup, dimensionless; ΔP TP_m is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the first position m; ΔP TP_n is the pressure difference between the first pressure sensor and the second pressure sensor when the leakage regulating device is in the second position n; A m is the first flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg; B m is the second flow coefficient of the discharge regulating device when it is in the first position, Pa 0.5 ·s / kg; A n is the first flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg; B n is the second flow coefficient of the discharge regulating device when it is in the second position, Pa 0.5 ·s / kg.

8. The method for measuring multiphase fluid flow rate according to claim 7, characterized in that: The first flow coefficient A is calculated according to formula (3); the second flow coefficient B is calculated according to formula (4); A x =f A (x)…………………………………………(3) f in formula (3) A A is calculated under single-phase liquid conditions according to the position i of the discharge regulating device. Li , the fitted function f A ; The A Li The calculation method is formula (5): In formula (5), ΔP Li is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase liquid conditions; M Li is the mass flow rate at position i under single-phase liquid conditions; B x =f B (x)…………………………………………(4) f in formula (4) B is the B calculated under single-phase gas conditions according to the position i of the different leakage regulating devices. Gi , the fitted function f B ; B Gi The calculation method is formula (6): In formula (6), ΔP Gi is the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase gas conditions, Pa; M Gi is the flow rate at position i under single-phase gas conditions, kg / s; A Li According to formula (5), Pa 0.5 ·s / kg.

9. The method for measuring multiphase fluid flow rate according to claim 7 or 8, characterized in that: The gas phase mass flow rate M in the multiphase fluid G Calculate according to formula (7): M G =M TP X G ……………………………………(7) In formula (7), M G is the gas phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass holdup, dimensionless; Optionally, the liquid phase mass flow rate in the multiphase fluid is calculated according to formula (8): M L =M TP (1-X G )……………………………………(8) In formula (8), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass holdup, dimensionless; Optionally, the oil phase flow rate in the multiphase fluid is calculated according to formula (9): M O =M L (1-X W )=M TP (1-X G )(1-X W )………………(9) In formula (9), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless; Optionally, the water phase flow rate in the multiphase fluid is calculated according to formula (10): M W =M L X W =M TP (1-X G )X W ………………………(10) In formula (10), M L is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP is the total mass flow rate of multiphase fluid, kg / s; X G is the gas phase mass fraction, dimensionless; X W is the moisture content, dimensionless.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program for a method for measuring gas-liquid two-phase flow rate, and when the program for the method for measuring gas-liquid two-phase flow rate is executed by a processor, the steps of the method for measuring gas-liquid two-phase flow rate as described in any one of claims 7 to 9 are implemented.

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