Variable flow area multiphase flow metering device and method

Abstract

The disclosure provides a kind of multiphase fluid metering device and method, the metering device includes: the flow pipe, the cyclone generation device, the flow regulation device and the flow collection device;The cyclone generation device is configured to cyclone the gas-liquid two-phase fluid in the flow pipe with the flow pipe axis as axis;The fluid outlet of the flow pipe is located in the side wall of the flow pipe;The flow regulation device is configured to adjust the size of the fluid outlet of the flow pipe;The flow collection device surrounds the flow pipe;First pressure sensor is provided between the cyclone generation device and the fluid outlet of the flow pipe;Second pressure sensor is provided on the inner wall of the flow collection device.The metering device is small in size, compact in structure, wide in application range, and can realize simultaneous measurement of multiphase fluid phase flow and gas, liquid phase mass content.

Description

TECHNICAL FIELD

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

[0002] Multiphase fluid is widely used in the fields of petroleum, chemical industry, energy and power. Online measurement of the phase flow rates of multiphase fluid is of great significance to the safe and efficient operation of production.

[0003] In a multiphase fluid conveying environment, conventional single-phase flow metering methods and devices cannot be applied, and multiphase flow metering methods can be generally classified into three types according to whether separation is performed and the degree of separation, i.e. separation, non-separation and split-phase methods. The complete separation method uses a three-phase separator to separate the multiphase fluid into oil, gas and water phases, and single-phase flow meters are used to measure the phase flow rates, which is not affected by multiphase flow fluctuations and has high precision. However, the separation equipment is bulky and expensive, which greatly increases the development cost of oil fields. The non-separation multiphase flow meter measures the oil, gas and water phases without any separation, and the main technical difficulty lies in the determination of the oil, gas and water phase component contents and the phase flow rates. The non-separation metering method does not require separation equipment and is small in size, but the measurement is easily affected by fluid fluctuations and has low precision.

[0004] Invention patent (application number: 201010588041.9) discloses a split-phase gas-liquid two-phase fluid flow meter, which has the characteristics that a part of the measured two-phase fluid is split to separate the single-phase gas and single-phase liquid, which are measured by single-phase flow meters, and then the flow rate of the measured two-phase fluid is inferred according to the proportional relationship. Compared with conventional multiphase metering methods, the split-phase method has the advantages of small size and high precision because the volume of the required separator is much smaller than that of the complete separation method, and the gas and liquid phase flow rates are measured in single-phase medium environments. In order to ensure the accuracy of the flow rate measurement, the split fluid and the measured two-phase fluid must have a stable and determined relationship. However, the multiphase fluid usually undergoes phase separation when flowing through the distributor, which leads to the loss of representativeness of the sampling fluid and increases the measurement error.

[0005] In recent years, Venturi and other throttling devices have been applied to flow measurement. Traditional throttling devices obtain the mass flow rate according to the differential pressure-flow rate relationship, but are only applicable to single-phase gas or liquid. For multiphase fluid, since there are two parameters, i.e. the total mass flow rate and the gas phase mass fraction, single differential pressure measurement cannot simultaneously obtain the two unknown parameters, and the oil, gas and water phase flow rates cannot be obtained. SUMMARY

[0006] In order to overcome the defects of the prior art, the present disclosure provides a variable flow area multiphase fluid metering device and method. The components of the device can be assembled and disassembled, and can be combined according to the size of the multiphase fluid flow to be metered. It has the advantages of wide measurement range, high measurement accuracy, simple operation, low cost, and is not affected by flow type changes, etc. It realizes continuous metering, and is especially suitable for the development of offshore oil and gas fields.

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

[0008] In an embodiment of the present disclosure, a multiphase fluid metering device is provided, which comprises a flow pipe, a rotational flow generating device, a flow regulating device and a flow collecting device.

[0009] The rotational flow generating device is configured to generate rotational flow of the multiphase fluid in the flow pipe with the flow pipe axis as the axis;

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

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

[0012] The flow collecting device surrounds the flow pipe;

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

[0014] A second pressure sensor is provided on the inner wall of the flow collecting device.

[0015] In an embodiment provided in the present application, the fluid outlet is a narrow slit structure penetrating the pipe wall, the sizes of the plurality of fluid outlets 9 are completely the same, they are all located on the same plane perpendicular to the central axis of the flow pipe, and are uniformly arranged along the circumference of the flow 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 an embodiment provided in the present disclosure, the rotational flow generating device is tubular, connected in series with the flow pipe, and the inner diameters of the two are the same; the flow pipe inlet is in communication with the outlet of the rotational flow generating device, and the other end of the flow pipe is closed, so that the fluid flows out from the fluid outlet. The rotational flow generating device is internally provided with a rotational flow device.

[0018] In an embodiment provided by the present disclosure, the cyclone is composed of a spiral blade and a central shaft, the outer edge of the spiral blade is tightly attached to the inner wall of the cyclone generation device, so that the liquid flowing through the cyclone rotates around the central shaft, so that the liquid in the gas-liquid two-phase is closer to the inner wall of the cyclone generation device, and the gas is closer to the central shaft.

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

[0020] In an embodiment provided by the present disclosure, the first pressure sensor is arranged on the inner wall of the pipe of the cyclone generation device.

[0021] The position of the first pressure sensor is (1 / 8 to 1 / 4)R distance from the point where the cyclone contacts the inner wall of the pipe of the cyclone generation device in the direction from the cyclone to the drain pipe.

[0022] The R is the inner diameter of the cyclone generation device.

[0023] The drain collection device is a cylindrical structure, the inner diameter of the drain collection device is greater than the outer diameter of the cyclone generation device, and the inlet end of the drain collection device is connected to the outlet end of the cyclone generation device through a flange. The multiphase flow metering device further comprises an outlet pipe, the inlet of the outlet pipe is in communication with the outlet of the drain collection device. The outlet pipe is installed on the outlet end surface of the drain collection device.

[0024] In an embodiment provided by the present disclosure, the second pressure sensor is arranged on the inner wall of the pipe of the drain collection device.

[0025] The position of the second pressure sensor is (0 to 1 / 8) r distance from the point where the drain collection device is connected to the cyclone generation device to any point on the pipe wall of the projection of the inner wall of the pipe of the drain collection device along the radial direction of the drain pipe.

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

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

[0028] In an embodiment provided by the present disclosure, the outer surface of the drain pipe is provided with threads, and the inner wall of the drain adjusting device is provided with internal threads corresponding to the threads. External threads are arranged on the outer wall of the drain adjusting device, which can be coupled with the driving screw and the supporting screw. The annular cavity formed by the outer wall of the drain adjusting device and the inner wall of the drain collecting device is provided with the supporting screw and the driving screw. The central axis of the driving screw is connected with a driving rod, the driving rod extends to the outside of the drain collecting cavity, and a handle is arranged at the end of the driving rod. The handle can be rotated to drive the driving screw to rotate and adjust the drain adjusting device to a specified position.

[0029] In an embodiment provided by the present disclosure, the inlet end of the rotational flow generating device is provided with a metering inlet flange, and the outlet pipe is provided with a metering outlet flange. The multiphase fluid metering device is connected in communication with the pipeline of the measured gas-liquid two-phase flow through the metering inlet flange and the metering outlet flange.

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

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

[0032] In another aspect, a method for measuring the flow of multiphase fluid is provided in an embodiment of the present disclosure, which uses the multiphase fluid metering device described above, and the method comprises:

[0033] By adjusting the drain adjusting device, the size of the fluid outlet of the drain pipe is adjusted. The first position of the drain adjusting device is recorded as m, and the second position is recorded as n.

[0034] The pressure difference ΔP TP_m between the first pressure sensor and the second pressure sensor when the drain adjusting device is at the first position m is obtained.

[0035] The pressure difference ΔP TP_n between the first pressure sensor and the second pressure sensor when the drain adjusting device is at the second position n is obtained.

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

[0037] The second flow coefficient B ranges from 19 to 299, the greater the fluid outlet of the drain pipe, the smaller the value of the second flow coefficient B, and the greater the pipe diameter of the drain pipe, the greater the value of the second flow coefficient B;

[0038] The parameters ΔP TP_m , ΔP TP_n , A, and B are brought into formula (1) and formula (2), and a binary equation set is solved to calculate the total mass flow M TP of the multiphase fluid and the gas phase mass fraction X G , so that the gas-liquid two-phase separated flow is measured.

[0039]

[0040]

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

[0042] ΔP TP_m is the pressure difference of the first pressure sensor and the second pressure sensor of the drain adjusting device at the first position m.

[0043] ΔP TP_n is the pressure difference of the first pressure sensor and the second pressure sensor of the drain adjusting device at the second position n.

[0044] A m is the first flow coefficient of the drain adjusting device at the first position, Pa 0.5 ·s / kg; B m is the second flow coefficient of the drain adjusting device at the first position, Pa 0.5 ·s / kg.

[0045] A n is the first flow coefficient of the drain adjusting device at the second position, Pa 0.5 ·s / kg; B n is the second flow coefficient of the drain adjusting device at the second position, Pa 0.5 ·s / kg.

[0046] In an embodiment provided in the present disclosure, the first flow coefficient A is calculated according to formula (3), and the second flow coefficient B is calculated according to formula (4).

[0047] A x = f A(x)…………………………………………(3)

[0048] f in formula (3) A Under single-phase liquid conditions, A is calculated based on the different positions i of the discharge regulating devices. Li The fitted function f A ;

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

[0050]

[0051] In formula (5), ΔP Li M represents the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase liquid conditions. Li Let i be 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 Under single-phase gas conditions, B is calculated based on the position i of different venting control devices. Gi The fitted function f B ;

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

[0055]

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

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

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

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

[0060] In an 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 M is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP M is the total mass flow rate of the multiphase fluid, kg / s; X G X is the gas phase mass fraction, dimensionless.

[0063] In an embodiment provided by the present disclosure, the oil phase mass 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 M is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TP M is the total mass flow rate of the multiphase fluid, kg / s; X G X is the gas phase mass fraction, dimensionless; X W X is the water cut, dimensionless.

[0066] In an embodiment provided by the present disclosure, the water phase mass 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 M is the liquid phase mass flow rate in the multiphase fluid, kg / s, M TPis the total mass flow rate of the multiphase fluid, kg / s; X G is the mass fraction of the gas phase, dimensionless; X W is the water cut, dimensionless.

[0069] In yet another aspect, the present disclosure provides a management device for measuring multiphase fluid flow, comprising a memory, a processor, and a management program for measuring gas-liquid two-phase flow stored on the memory and executable on the processor, which, when executed by the processor, implements the steps of the method for measuring gas-liquid two-phase flow as described above.

[0070] In yet another aspect, the present disclosure provides a computer-readable storage medium having stored thereon a program of a method for measuring gas-liquid two-phase flow, which, when executed by a processor, implements the steps of the method for measuring gas-liquid two-phase flow as described above.

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

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

[0073] (2) Under the action of the cyclone, the wave 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 measurement.

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

[0075] Other features and advantages of the present disclosure will be set forth in the following description, and will in part be apparent from the description, or will be learned by practice of the present disclosure. Other advantages of the present disclosure will be realized and attained by the schemes described in the specification and drawings. BRIEF DESCRIPTION OF DRAWINGS

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

[0077] Figure 1 is a schematic view of the device provided by the present disclosure.

[0078] Figure 2 is a schematic view of the structure of the cyclone generating device and the flow pipe.

[0079] Figure 3 is a schematic view of an A-A cross section of the flow regulating device. Figure 1

[0080] Figure 4 is a schematic view of the flow regulating device structure.

[0081] Figure 5 is a schematic view of the flow collection chamber and outlet pipe structure.

[0082] Figure 6 is a schematic view of the cyclone structure.

[0083] Figure 7 is a schematic view of the cyclone rectification.

[0084] BRIEF DESCRIPTION OF DRAWINGSFigure 1 is a schematic view of a flow generating device. Figure 2 is a schematic view of a flow regulating device. Figure 3 is a schematic view of a flow collection device. Figure 4 is a schematic view of an outlet pipe. Figure 5 is a schematic view of a first pressure sensor. Figure 6 is a schematic view of a second pressure sensor. Figure 7 is a schematic view of a cyclone. Figure 8 is a schematic view of a fluid outlet. Figure 9 is a schematic view of a position indicating scale. Figure 10 is a schematic view of a support screw. Figure 11 is a schematic view of a drive screw. Figure 12 is a schematic view of a drive rod. Figure 13 is a schematic view of a handle. Figure 14 is a schematic view of an upstream pressure tapping point. Figure 15 is a schematic view of a downstream pressure tapping point. Figure 16 is a schematic view of a meter inlet flange. Figure 17 is a schematic view of a meter outlet flange. Figure 18 is a schematic view of a central shaft. Figure 19 is a schematic view of a helical blade. DETAILED DESCRIPTION

[0085] The present disclosure describes a number of embodiments, but this description is exemplary rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the embodiments described in the present disclosure. Although a number of possible combinations of features have been set forth in the appended drawings and discussed in the detailed description, many other combinations of features are possible. Any feature of any embodiment can be used in combination with any other feature or element of any other embodiment, or in replacement of any other feature or element of any other embodiment, unless specifically restricted otherwise.

[0086] The present disclosure includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The presently disclosed embodiments, features and elements can also be combined with any conventional feature or element to form a unique application defined by the claims. Any feature or element of any embodiment can also be combined with features or elements from other application to form another unique application defined by the claims. Therefore, it is to be understood that any feature shown and / or discussed in the present disclosure can be implemented alone or in any appropriate combination. Embodiments, therefore, are not to be limited by any of the illustrated embodiments set forth herein. Rather, they are to be limited only by the claims set forth and equivalents thereof.

[0087] Furthermore, in describing representative embodiments, the specification can have presented the method and / or process as a particular sequence of steps. However, to the extent that the method or process depends on more than one step, the method or process should not be limited to the particular sequence of steps described. Other sequences of steps can be possible, and are within the scope of the present disclosure. Therefore, as the skilled artisan will appreciate, the sequence of steps described in the specification is illustrative only and does not limit the scope of the present disclosure. Additionally, any step of the method and / or process can be performed in any appropriate order, as will be appreciated by those skilled in the art. The implementations outlined herein will primarily address the problem of providing a multiphase flow metering device.

[0088] As shown in Figure 1 , an exemplary multiphase flow metering device is provided in the present disclosure, the metering device comprising: a flow pipe 2, a rotational flow generating device 1, a flow regulating device 3 and a flow collection device 4;

[0089] The rotational flow generating device 1 is configured to generate rotational flow of gas-liquid two-phase fluid within the flow pipe 2 about the flow pipe 2 axis;

[0090] The fluid outlet of the flow pipe 2 is located at the side wall of the flow pipe 2;

[0091] The flow regulating device 3 is configured to regulate the size of the fluid outlet 9 of the flow pipe 2;

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

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

[0094] A second pressure sensor 7 is provided at the inner wall of the flow collection device 4.

[0095] Exemplarily, as shown in Figure 1 ,Figure 3 As shown in the figure, the fluid outlet 9 is a narrow slit structure penetrating the pipe wall, the sizes of the plurality of fluid outlets 9 are completely the same, they are located on the same plane perpendicular to the central axis of the flow pipe 2, and are uniformly arranged along the pipe circumference of the flow 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] Exemplarily, as shown in the figure, Figure 2 , Figure 3 As shown in the figure, the rotational flow generating device 1 is tubular, in series with the flow pipe 2, and the inner diameters of the two are the same; the inlet of the flow pipe 2 communicates with the outlet of the rotational flow generating device 1, and the other end of the flow pipe 2 is closed, so that the fluid flows out from the fluid outlet 9. The rotational flow generating device 1 is internally provided with a rotational flow generator 8.

[0098] Exemplarily, as shown in the figure, Figure 1 , Figure 2 and Figure 6 The rotational flow generator 8 is composed of a spiral blade 21 and a central shaft 20, the outer edge of the spiral blade 21 is fixedly attached to the inner wall of the rotational flow generating device 1, so that the liquid flowing through the rotational flow generator 8 rotates around the central shaft 20. Because the density of the gas phase is much smaller than that of the liquid phase, the liquid in the gas-liquid two-phase is closer to the inner wall of the rotational flow generating device 1, and the gas is closer to the central shaft 20. As shown in the figure, Figure 7 For a horizontal pipe without a rotational flow device, under the action of gravity, the gas-liquid distribution in the pipe cross section presents obvious asymmetry, the liquid phase is more at the bottom, and the gas phase is mainly concentrated in the upper part of the rotational flow generating device 1. As shown in the figure, Figure 7 When the rotational flow generator 8 exists, the stratified flow, wave flow, semi-ring flow, and asymmetric ring flow are adjusted to a uniform ring flow type with consistent circumferential distribution.

[0099] Exemplarily, as shown in the figure, Figure 1 The first pressure sensor 6 (or the pressure taking point of the first pressure sensor 6, i.e. the upstream pressure taking point 16) is arranged on the inner wall of the pipe between the rotational flow generator 8 and the flow pipe 2.

[0100] Exemplarily, the first pressure sensor 6 (or the pressure taking point of the first pressure sensor 6, i.e. the upstream pressure taking point 16) is arranged on the inner wall of the pipe of the rotational flow generating device; the position of the first pressure sensor 6 (or the pressure taking point of the first pressure sensor 6, i.e. the upstream pressure taking point 16) is: in the direction from the rotational flow generator 8 to the flow pipe 2, at a distance of (1 / 8 to 1 / 4) R from the point where the rotational flow generator 8 contacts the inner wall of the pipe of the rotational flow generating device 1;

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

[0102] As shown in Figure 1 , Figure 2 and Figure 5 , the leakage collection device 4 is a cylindrical structure, the inner diameter of the leakage collection device 4 is greater than the outer diameter of the rotational flow generating device 1, and the inlet end of the leakage collection device 4 is connected to the outlet end of the rotational flow generating device 1 through a flange. The multiphase flow metering device further comprises an outlet pipe 5, the inlet of the outlet pipe 5 is in communication with the outlet of the leakage collection device. The outlet pipe 5 is installed on the outlet end surface of the leakage collection device 4.

[0103] The second pressure sensor 7 (or the pressure taking point of the second pressure sensor 7, i.e. the downstream pressure taking 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 taking point of the second pressure sensor 7, i.e. the downstream pressure taking point 17) is: from the rotational flow device 8 to the leakage pipe 2, from the connection of the leakage collection device 4 and the rotational flow generating device 1 to any point of the projection of the inner wall of the pipe of the leakage collection device 4 along the radial direction of the leakage pipe 2, at a distance of (0 to 1 / 8) r;

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

[0106] Exemplarily, a differential pressure sensor can be connected between the upstream pressure taking point and the downstream pressure taking point to directly test the differential pressure between the upstream pressure taking point and the downstream pressure taking point. Through this arrangement, the second pressure sensor can be equivalent.

[0107] Exemplarily, the leakage adjusting device 3 is cylindrical, and the leakage adjusting device 3 surrounds and is attached to the outer wall of the leakage pipe 2.

[0108] Exemplarily, as shown in Figure 1 and Figure 4 , one end of the leakage adjusting device 3 is closed, and a position indicating scale 10 is arranged at the center of the outer bottom surface of the closed end, and the leakage adjusting device 3 is sleeved on the leakage pipe 1.

[0109] Exemplarily, as shown in Figure 1 , Figure 2 and Figure 4 , the outer surface of the leakage pipe 2 is provided with threads, and the inner wall of the leakage adjusting device 3 is provided with internal threads corresponding to the threads.

[0110] Exemplarily, as shown in Figure 1 , Figure 2 and Figure 4As shown, the outer wall of the leakage adjusting device 3 is provided with external threads, which can be coupled with the driving screw 12 and the supporting screw 11, which are fixed with the outer wall of the leakage collection device 4 and cannot move relative to the respective screw when rotating. The annular cavity formed by the outer wall of the leakage adjusting device 3 and the inner wall of the leakage collection device 4 is provided with the supporting screw 11 and the driving screw 12. The central axis 13 of the driving screw is connected with the driving rod 14, which extends to the outside of the cavity surrounded by the leakage collection device 4 and the vortex generating device 1. The end of the driving rod 14 is provided with a handle 15, which can drive the driving rod 14 to rotate the driving screw 12 by rotating the handle 15. The driving screw 12 and the threads on the leakage adjusting device 3 can drive the leakage adjusting device 3 to move forward and backward, so as to adjust the leakage adjusting device 3 to the designated position and change the leakage area of the fluid outlet 9.

[0111] As shown in the drawings, Figure 1 As shown, the inlet end of the vortex 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 in communication with 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 disclosure exemplarily provides a method for measuring the flow of multiphase fluid, which uses the multiphase fluid metering device described above, and the method comprises:

[0113] By adjusting the leakage adjusting device, the size of the fluid outlet of the leakage pipe is adjusted. The first position of the leakage adjusting device is denoted as m, and the second position is denoted as n.

[0114] The pressure difference ΔP TP_m between the first pressure sensor and the second pressure sensor when the leakage adjusting device is at the first position m is obtained.

[0115] The pressure difference ΔP TP_n between the first pressure sensor and the second pressure sensor when the leakage adjusting device is at the second position n is obtained.

[0116] The first flow coefficient A is in the range of 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 pipe diameter of the leakage pipe is, the larger the value of the first flow coefficient A is.

[0117] The second flow coefficient B is in the range of 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 pipe diameter of the leakage pipe is, the larger the value of the second flow coefficient B is.

[0118] The parameters ΔP TP_m , ΔPTP_n , A, B are substituted into equation (1) and equation (2), and a binary equation set is solved to calculate the total mass flow M of the multiphase fluid TP and the gas phase mass fraction X G , realizing measurement of the gas-liquid two-phase separated flow;

[0119]

[0120]

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

[0122] ΔP TP_m is the pressure difference of the first pressure sensor and the second pressure sensor of the flow regulating device at the first position m;

[0123] ΔP TP_n is the pressure difference of the first pressure sensor and the second pressure sensor of the flow regulating device at the second position n;

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

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

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

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

[0128] In equation (3), f A is a function f Li calculated according to different positions i of the flow regulating device under the condition of single-phase liquid, and a fitted function f A ;

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

[0130]

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

[0132] B x = f B (x) … … … (4)

[0133] In formula (4), f B is the function f Gi obtained by fitting B B calculated according to different position i of the flow regulating device under the condition of single-phase gas;

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

[0135]

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

[0137] Exemplarily, the gas phase mass flow M G in the multiphase fluid is calculated according to formula (7):

[0138] M G = M TP X G … … … (7)

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

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

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

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

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

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

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

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

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

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

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

[0150] ​​​Using the aforementioned apparatus and method, the three-phase flow rates of oil, gas, and water in a multiphase produced fluid from an oil well are measured at the wellhead by adjusting the position of the discharge regulating device. This is achieved by solving for the total mass flow rate M. TP and gas phase mass content X G The solution to the system of two equations is as follows:

[0151] Gas phase mass flow rate: M G =M TP X G =0.188 kg / s × 3.14% = 0.0059 kg / s; Liquid phase 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 flow rate of oil phase and water phase separation:

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

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

[0155] The oil and water production were converted to tons per day, and the three-phase mass flow rates of oil, gas, and water were compared with the actual measured flow rates of the single well's daily production by field separation metering. The metering error was calculated, and the measurement results are as follows.

[0156] Table 1 Comparison of Measurement Effects

[0157]

[0158] It is evident that the measurement method provided in this application has high accuracy. The calculation results have an error of less than 3% compared with the measured values ​​of multiphase fluid separation metering, which is far below the requirement of the maximum permissible error of less than 15% as required by the "Oilfield Oil and Gas Gathering and Transportation Design Specification GB50350-2015".

[0159] In yet another aspect, the present disclosure provides a management device for measuring gas-liquid two-phase flow, which comprises a memory, a processor, and a management program for measuring gas-liquid two-phase flow stored on the memory and executable on the processor, which, when executed by the processor, implements the steps of the method for measuring gas-liquid two-phase flow as described above.

[0160] In yet another aspect, the present disclosure provides a computer-readable storage medium, which stores a program of a method for measuring gas-liquid two-phase flow, which, when executed by a processor, implements the steps of the method for measuring gas-liquid two-phase flow as described above.

[0161] In summary, as shown in Figure 1 the gas-liquid two-phase flow passes through the device provided by the present disclosure, the effective flow area of the fluid only depends on the position of the flow regulation device 3, and by operating the handle 15, the effective length of the fluid outlet 9 of the flow regulation device 2 can be changed, thereby changing the flow area. In actual application, the position of the flow regulation device 3 can be adjusted according to the size of the upstream flow, and by measuring the differential pressure at two different positions, the simultaneous measurement of the total mass flow and the gas phase mass fraction of the multiphase fluid can be realized.

[0162] The technical solution provided by the present disclosure is not affected by factors such as pipe gas-liquid phase flow type and pressure distribution, has a simple structure, basically requires no maintenance, and has wide applicability.

[0163] Those of ordinary skill in the art will realize and understand that all or some of the steps in the methods disclosed above and the functional modules / units in the systems and devices can be implemented as software, firmware, hardware, and appropriate combinations thereof. In hardware implementation, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be performed by several physical components in cooperation. Some or all of the components can be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on computer-readable media, which can include computer storage media (or non-transitory media) and communication media (or transitory media). As is well known to those of ordinary skill in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is 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 which can be used to store the desired information and which can be accessed by a computer. Furthermore, it is common and well understood by those of ordinary skill in the art that communication media typically embodies 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 can include any information delivery media.

Claims

1. A multiphase fluid metering device with variable flow area, characterized in that, The multiphase fluid metering device includes: a drain pipe, a vortex generator, a drain regulating device, and a drain collecting device; The swirling device is configured to swirl the gas-liquid two-phase fluid in the drain pipe with the axis of the drain pipe as the axis, and the swirling device is equipped with a swirler inside; The fluid outlet of the drain pipe is located on the side wall of the drain pipe; The discharge regulating device is configured to adjust from a first position to a second position to adjust the size of the fluid outlet of the discharge pipe; The discharge collection device surrounds the discharge pipe; A first pressure sensor is provided between the vortex generator and the fluid outlet of the drain pipe; A second pressure sensor is provided on the inner wall of the leakage collection device; The multiphase fluid metering device is configured to acquire the pressure difference between the first pressure sensor and the second pressure sensor when the venting regulating device is in the first position; and to acquire the pressure difference between the first pressure sensor and the second pressure sensor when the venting regulating device is in the second position.

2. The multiphase fluid metering device according to claim 1, characterized in that, The swirl generator is cylindrical and connected in series with the drain pipe.

3. The multiphase fluid metering device according to claim 1, characterized in that, The first pressure sensor is disposed on the inner wall of the pipe between the hydrocyclone and the drain pipe.

4. The multiphase fluid metering device according to claim 3, characterized in that, The first pressure sensor is disposed on the inner wall of the tube of the swirling generator; the position of the first pressure sensor is: 1 / 8R to 1 / 4R distance from the point where the swirling generator contacts the inner wall of the tube of the swirling generator in the direction of the drain pipe. R is the inner diameter of the vortex generator.

5. The multiphase fluid metering device according to any one of claims 1 to 3, characterized in that, The discharge regulating device is cylindrical, surrounds the outer wall of the discharge pipe, and fits against the outer wall of the discharge pipe.

6. The multiphase fluid metering device according to claim 5, characterized in that, The second pressure sensor is disposed on the inner wall of the pipe of the leakage collection device; The position of the second pressure sensor is: from the point where the cyclone separator is connected to the cyclone generator in the direction of the drain pipe, to any point on the pipe wall from the fluid outlet of the drain pipe along the radial direction of the drain pipe to any point on the inner wall of the drain pipe, at a distance of 0 to 1 / 8r. r is the inner diameter of the discharge collection device.

7. A method for measuring the flow rate of a multiphase fluid, characterized in that, Using the multiphase fluid metering device according to any one of claims 1 to 6, the method comprises: The size of the fluid outlet of the drain pipe is adjusted by adjusting the drain regulating device. The first position of the drain regulating device is denoted as m, and the second position is denoted as n. The pressure difference ΔP between the first pressure sensor and the second pressure sensor of the discharge regulating device at the first position m is obtained. TP_m ; The pressure difference ΔP between the first pressure sensor and the second pressure sensor of the discharge regulating device at the second position n is obtained. TP_n ; The value of the first flow coefficient A ranges from 299 to 2999. The larger the fluid outlet of the drain pipe, the smaller the value of the first flow coefficient A; the larger the pipe diameter of the drain pipe, the larger the value of the first flow coefficient A. The value of the second flow coefficient B ranges from 19 to 299. The larger the fluid outlet of the drain pipe, the smaller the value of the second flow coefficient B; the larger the diameter of the drain pipe, the larger the value of the second flow coefficient B. The parameter ΔP TP_m ΔP TP_n Substitute A and B into formulas (1) and (2) to calculate the total mass flow rate M of the multiphase fluid. TP and gas phase mass content X G This allows for the measurement of gas-liquid two-phase flow rates; In formulas (1) and (2), M TP X represents the total mass flow rate of the multiphase fluid, in kg / s; G The mass content of the gas phase is dimensionless. ΔP TP_m The pressure difference between the first pressure sensor and the second pressure sensor when the discharge regulating device is at the first position m; ΔP TP_n The pressure difference between the first pressure sensor and the second pressure sensor when the discharge regulating device is in the second position n; A m Pa is the first flow coefficient of the discharge regulating device in the first position. 0.5 ·s / kg; B m Pa is the second flow coefficient of the discharge regulating device in the first position. 0.5 ·s / kg; A n Pa is the first flow coefficient of the discharge regulating device in the second position. 0.5 ·s / kg; B n Pa is the second flow coefficient of the discharge regulating device in the second position. 0.5 ·s / kg.

8. The method for measuring the flow rate of a multiphase fluid 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 Under single-phase liquid conditions, A is calculated based on the different positions i of the discharge regulating devices. Li The fitted function f A ; The A Li The calculation method is formula (5): In formula (5), ΔP Li M represents the pressure difference between the first pressure sensor and the second pressure sensor at position i under single-phase liquid conditions. Li Let i be the mass flow rate at position i under single-phase liquid conditions; B x =f B (x)…………………………………………(4) f in formula (4) B Under single-phase gas conditions, B is calculated based on the position i of different venting control devices. Gi The fitted function f B ; The B Gi The calculation method is formula (6): In formula (6), ΔP Gi The pressure difference between the first and second pressure sensors at position i under single-phase gas conditions is expressed in Pa and M. Gi A is the flow rate at position i under single-phase gas conditions, in kg / s; Li Pa is calculated according to formula (5). 0.5 ·s / kg.

9. The method for measuring the flow rate of a multiphase fluid 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 The mass flow rate of the gas phase in a multiphase fluid is kg / s, M. TP X represents the total mass flow rate of the multiphase fluid, in kg / s; G The mass content of the gas phase is dimensionless. The mass flow rate of the liquid phase in the multiphase fluid is calculated according to formula (8): M L =M TP (1-X G )……………………………………(8) In formula (8), M L The mass flow rate of the liquid phase in a multiphase fluid is kg / s, M. TP X represents the total mass flow rate of the multiphase fluid, in kg / s; G The mass content of the gas phase is dimensionless. 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 The mass flow rate of the liquid phase in a multiphase fluid is kg / s, M. TP X represents the total mass flow rate of the multiphase fluid, in kg / s; G X represents the gas phase mass content, dimensionless; W Moisture content, dimensionless; The aqueous 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 The mass flow rate of the liquid phase in a multiphase fluid is kg / s, M. TP X represents the total mass flow rate of the multiphase fluid, in kg / s; G X represents the gas phase mass content, dimensionless; W Moisture content, dimensionless.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program for a method of measuring gas-liquid two-phase flow rate, which, when executed by a processor, implements the steps of the method for measuring gas-liquid two-phase flow rate as described in claim 7 or 8.

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