RU2334201C1 - Flow rate measuring system of gas-liquid borehole flow agents - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: system contains two high-frequency resonators mounted on dielectric pipe, each of which represents short-circuited meander lined conductor with two mutually orthogonal inputs-outputs, constraint and constraint-dividing coils, Coriolis acceleration flowmeter with electronic flow and density transducers, pressure probe, computing controller, controlled high-frequency alternator and switchboard, flow pattern controller, first and second calibration controllers of Coriolis acceleration flowmeter, two input amplifiers, four transmitting paths and eight blocking capacitors. Using radio high-frequency flow probing method in two mutually orthogonal directions the volume content of flow agents is measured. While autocorrelation flow velocity variation method combined with Coriolis acceleration flowmeter and calibration controllers is used to measure flow rate and density of controlled medium. Calibration controllers assuming flow pattern controller data allow for selection of stored array calibration of Coriolis acceleration flowmeter according to specified pattern.

EFFECT: invention raises accuracy of measurement even at essentially unsteady current of a stream.

5 dwg

Description

The invention relates to measuring equipment and can be used in the oil industry, for example, to control the flow rate of oil wells.

A known system for measuring the component flow rate of a multiphase flow of oil wells containing oil, gas and water (see RF patent No. 2270981, IPC G01F 15/08, G01F 1/74, G01F 1/84, E21B 47/10).

This system contains a separator that provides separation of the gas and liquid components of the controlled flow, as well as mass flow measurement devices and other component parameters, including a microwave moisture meter that determines the water content in the liquid component by radio wave sensing.

The disadvantage of this system is the impossibility of determining the component composition of a multiphase flow without prior separation: mechanical separation into gas and liquid fractions.

Also known are systems for measuring the component flow rate of a three-component gas-liquid stream, comprising a controlled microwave generator, a probe unit with antennas and a computer control unit (see RF patent No. 2063615, IPC G01F 1/56, RF patent No. 43068, IPC G01F 1/74 and RF patent No. 2275604, IPC G01F 1/74). These systems do not require separation of the gas-liquid stream, however, they have another drawback: the impossibility of reliable radio-wave sounding of the controlled stream in the presence of salt water in it. This disadvantage is due to the attenuation of microwave radio emission of the sounding unit of known systems in substantially conductive salt water. Since the content of salts dissolved in the well water is tens of grams per liter, the well water has high electrical conductivity, which makes it virtually opaque to microwave radiation and does not allow reliable monitoring of the water content.

The known device for measuring the component flow rate of a multi-component gas-liquid-solid-state flow (see the description of the application for invention of the Russian Federation No. 2002100228, IPC G01F 1/00, G01F 5/00, the second version of the product shown in Figure 2) and a complex measuring component flow rate are free from this drawback three-component gas-liquid flow of oil wells (see RF patent for utility model No. 589814, IPC G01F 1/00, G01F 5/00, ЕВВ 47/10).

Each of the known devices includes two coaxially arranged high-frequency resonators made in the form of short-circuited zigzag conductors, as well as a computer-control unit, a pressure sensor, a controlled RF generator and transmitting paths, each of which contains an amplifier and an amplitude detector connected in series and analog-to-digital converter. In the known device and complex, the measurement of the volume component flow rate is carried out by the autocorrelation method by sensing a controlled gas-liquid flow by high-frequency resonators with a radiation frequency specified by a controlled high-frequency generator.

The calculation of the mass component flow rate is carried out indirectly in the computing and control unit based on information about the volume flow rate of the controlled medium, taking into account the pressure signals generated by the pressure sensor.

Since in relation to the high-frequency radiation, the flow of the well fluid is practically radiolucent, these systems make it possible to accurately control the average velocity and volumetric flow rate of the well fluid even when it contains salt water.

However, a prerequisite for the operation of known systems is the presence in the controlled flow of significant fluctuations in its component composition, for example, the presence of distinct gas bubbles. In the absence of such fluctuations, the autocorrelation method is inoperative and these systems cease to function.

This drawback is eliminated in the known system for measuring the component liquid mass flow of a three-component gas-liquid flow of oil wells (see the description of the application for the invention of the Russian Federation No. 2002100228, IPC G01F 1/00, G01F 5/00, the third version of the product shown in Figure 3).

This system is the closest to the proposed invention in terms of technical nature and the achieved result and is taken as the closest analogue (prototype). The composition of the known system includes a high-frequency resonator made in the form of a short-circuited zigzag conductor having the shape of a rectangular meander located on a dielectric pipe installed in a pipe segment, controlled by an RF generator, a pressure sensor, a common flow meter installed in series with a high-frequency resonator and equipped with an electronic a flow converter, as well as a computing and control device and a transmitting path, which is consistently connected interconnected amplifier, detector and analog-to-digital converter (ADC).

The known system is based on two measurement methods: the method of measuring the component composition of the controlled flow in fractions of the total volume, followed by correction of the received information on pressure and temperature, and the method of measuring the total volume flow of the controlled flow. The measurement of the component composition of the flow in fractions of the volume is based on the use of the method of high-frequency radio wave sounding of a controlled medium using a high-frequency resonator; In this method, the informative parameters of the output signal about the component-wise composition of the flow in fractions of the volume are the absorption parameters of the high-frequency electromagnetic field of the resonator at the resonant frequencies, controlled by the medium.

The determination of the component composition of the flow in mass fractions is based on the use of information from the pressure sensor of the controlled medium, which allows, indirectly, using reference data on the nominal density values of each of the three components of the gas-liquid flow: oil, water and gas, to convert volume fractions into mass ones.

The measurement of the total volumetric flow rate of the controlled flow in a known system is performed using a mechanical meter of "metered movement" or an ultrasonic flowmeter equipped with an electronic transducer that generates an electrical output signal about the total volumetric flow rate of the controlled flow.

The open cylindrical high-frequency resonator of this system is a short-circuited zigzag conductor equipped with a separate input and a separate output of high-frequency signals, and the output of the high-frequency resonator of the known system is connected to one of the inputs of the computer-control unit through the transmission path, and the input of this high-frequency resonator is connected to the output of the controlled high-frequency generator through the input amplifier, while the input and output of the high-frequency resonator is connected Nena each to one of two distinct, diametrically oppositely arranged outlets shorted zigzag conductor lying in one transverse plane.

Due to the fact that the known system uses a high-frequency signal as a probing radio wave signal, it makes it possible to probe a gas-liquid stream at a relatively low frequency compared to microwave radiation, which makes it possible to reliably control the volume content of gas-liquid stream components even if it contains salt water.

However, the disadvantage of this system is the high measurement error of the relative content of gas-liquid flow components in fractions of the mass, caused, firstly, by using the indirect method of measuring the mass content of these components, based on the pressure of the controlled medium and, secondly, by the additional error of radio wave measurements, arising at essentially unsteady flow of a controlled stream.

The error of the indirect method for measuring the mass content of components arises in connection with the difference in the memory of the computer-control device of the known system of nominal reference values of the density of the components of the gas-liquid flow: oil, water and gas from the actual density values of each of these components. Actual density values may vary significantly from nominal values. So, for example, the density of well water, depending on its salinity, varies from 1 to 1.2 g / cm ³ , which cannot be taken into account in the known system, since the output signals of the radio wave sensor and the flow meter of the total flow included in the known system , depend not on the mass and not on the mass flow rate of the components, but on their volume and volumetric flow rate.

The component composition and speed of the gas-liquid flow of oil wells at an unsteady flow characteristic of their work quickly and randomly change in time, as a result of which the additional error of radio wave measurements caused by the “lag” in the speed of the algorithmic processing of the results of autocorrelation data in the computing-control device of a known system from the rate of change information on the component composition of the gas-liquid flow can reach significant values.

The objective of the invention is to provide a system capable of measuring the mass flow rate of individual components (oil, water, gas) of an oil well stream.

The technical result achieved is an increase in the reliability and accuracy of the measurements of the component-wise mass flow rate of the gas-liquid stream.

To solve this problem, a system for measuring the mass flow rate of components of a gas-liquid flow of oil wells, which includes the first high-frequency resonator, which is a short-circuited conductor having the shape of a rectangular meander, placed on the outer cylindrical surface of the dielectric pipe located inside the tubular metal body coaxially with it, a flowmeter, installed in series with the first high-frequency resonator and equipped with an electronic converter a descent, a pressure sensor installed in a dielectric tube, a computing and control unit, a controlled high-frequency generator, a first input amplifier, as well as a transmission path, consisting of an amplifier connected in series with each other, the input of which serves as an input to this path, an amplitude detector, and an analog-to-digital converter the output of which serves as the output of this path, and the output of the pressure sensor is connected to the corresponding input of the computer-control unit, the first high-frequency resonator key via a first input to the output amplifier managed high-frequency generator, and via a transmission path - the corresponding entry computational and control unit, whose output is connected to the input of the high frequency generator managed, updated with new elements and connections.

In accordance with the invention, the proposed system is supplemented by a second high-frequency resonator mounted coaxially with the first high-frequency resonator on said dielectric tube inside said housing, each of said high-frequency resonators is equipped with two I / O: a first input-output and a second input-output located in diametrical mutually perpendicular planes.

As the flowmeter in the proposed system, a mass Coriolis flowmeter is used, equipped with an electronic flow transducer and an electronic density transducer.

In addition, three controllers are additionally introduced into the proposed system: a mode controller for determining the gas-liquid flow mode, a first calibration controller for calibrating the Coriolis flowmeter signals about the mass flow rate of the controlled medium, and a second calibration controller for calibrating the Coriolis flowmeter signals about the density of the controlled medium, as well as three transmission paths identical to the mentioned transmission path, four input and four output x isolation capacitors, a second input amplifier and a managed switch equipped with two outputs, one of which is connected to the input of the first input amplifier, and the second to the input of the second input amplifier, while the input of the managed switch is connected to the output of the controlled high-frequency generator, and the control input of the aforementioned the switch is connected to the corresponding output of the computing and control unit.

Each first and every second input-output of each of the high-frequency resonators of the proposed system is connected through one of the output isolation capacitors to the input of one of the transmission paths, the output of which is connected to the corresponding input of the computer-control unit and to one of the inputs of the mode controller, the output of which is connected to one of the inputs of the first calibration controller, to one of the inputs of the second calibration controller and to the corresponding input of the computing-control unit.

The other input of each of these calibration controllers is connected to the output of one of the electronic transducers: the input of the first calibration controller is connected to the output of the electronic flow transducer, and the input of the second calibration controller is connected to the output of the electronic density transducer, while the output of the pressure sensor is additionally connected to the corresponding input of the calibration controller .

In addition, each of the first I / O of each of the high-frequency resonators is connected through the input dividing capacitor to its output to the output of the first input amplifier, and each of the second I / O of each of the high-frequency resonators is connected through the corresponding input dividing capacitor to the output of the second input amplifier.

At the end sections of the dielectric tube, a short-circuited limiting coil (hereinafter referred to as a limiting coil) is installed, and a short-circuited limiting-separation coil (hereinafter referred to as a limiting-separation coil) is installed between high-frequency resonators, while the cross section of the limiting coil, the cross section of the limiting -dividing coil and the cross section of the short-circuited conductor of each of the above high-frequency resonators has a rectangular form.

To ensure maximum quality factor of each high-frequency resonator and to reduce inter-turn electrical capacitive connections between parallel sections of a short-circuited conductor, the following relationships between the sizes of a short-circuited conductor, a limiting coil and a limiting-dividing coil are established in the proposed system.

The thickness of the cross section b of the short-circuited conductor, the limiting coil and the limiting-dividing coil is determined by the inequality

where K is the dimensional coefficient of proportionality;

F _max - the upper limit of the signal frequency at the output of a controlled high-frequency generator.

The cross-sectional width of the short-circuited conductor of the high-frequency resonator is equal to the distance between its two adjacent parallel sections along the longitudinal axis

a = d

where a is the width of the cross section of a short-circuited conductor of a high-frequency resonator;

d is the distance between adjacent parallel sections of the short-circuited conductor of the high-frequency resonator, directed along the longitudinal axis, and is limited by the double inequality

10b≥a≥5b,

where b is the thickness of the cross section of a shorted conductor.

The proposed system includes the following main blocks: a high-frequency probe, a flowmeter, which is used as a Coriolis mass flowmeter, and an electronic measuring and computing device.

In more detail the essence of the invention is illustrated in the following example and is illustrated by drawings, which show:

Figure 1 is a functional diagram of the proposed system, figure 2 is a scan of high-frequency resonators, figure 3 is a cross section of a short-circuited conductor, figure 4 is a cross section of a high-frequency resonator, and figure 5 is a structural diagram of a transmitting path.

The following notation is introduced in the drawings:

1 - housing, 2 - first resonator, 3 - second resonator, 4 - first resonator input-output, 5 - second resonator input-output, 6 - dielectric tube, 7 - centering lock, 8 - outer o-ring, 9 - inner o-ring ring, 10 - restrictive coil, 11 - restrictive - separation coil, 12 - dielectric sleeve, 13 - dielectric substrate worn on the pipe 6 (hereinafter - dielectric substrate), 14 - pressure sensor, 15 - Coriolis flowmeter, 16 - electronic controlled mass flow signal converter medium (hereinafter referred to as a flow transducer), 17 is an electronic signal converter of the density of the controlled medium (hereinafter referred to as a density transducer), 18 is a fastener, 19 is a gasket, 20 is a computer-control unit, 21 is a controlled high-frequency generator, 22 - managed switch, 23 - mode controller, 24 - first calibration controller, 25 - second calibration controller, 26 - first input amplifier, 27 - second input amplifier, 28 - first transmission path, 29 - second transmission path, 30 - output amplifier, 31 - amplit projectile loader detector, 32 - ADC, 33 - input coupling capacitor 34 - output decoupling capacitor 35 - external system.

The high-frequency probe contains a housing 1, which is a segment of a metal pipe with flanges at its ends, one of which is designed to connect the housing 1 to the external oil pipeline, and the other to the flange of the Coriolis flowmeter 15, and two open cylindrical high-frequency resonators: the first resonator 2 and the second the resonator 3 mounted inside the housing 1 is aligned with it. Each of these resonators is a short-circuited zigzag conductor having the shape of a rectangular meander placed on the cylindrical surface of the dielectric tube 6.

The first input-output 4 is connected to one of the points of the short-circuited conductor of each of the resonators 2, 3, and the second input-output 5 is connected to the other point of the same conductor. Moreover, for each resonator the connection points of the first input-output 4 and the connection point of the second input- pin 5 lie in diametrical mutually perpendicular planes. Moreover, these points 4, 5 can be located either on opposite ends of each of the resonators 2, 3, as shown in Figs. 1 and 2, or can be on the same end of the corresponding resonator 2, 3.

Resonators 2, 3 are located on the outer cylindrical surface of a common dielectric pipe 6, axisymmetrically mounted inside the housing 1 using two end-centering clamps 7, each of which is equipped with two o-rings: an outer o-ring 8 and an inner o-ring 9.

In addition to the resonators 2, 3, metal short-circuited coils are installed on the outer surface of the dielectric tube 6: a restrictive-dividing coil 11 and two restrictive coils 10, one of the limiting coils 10 mounted on the side of the outer end of the first resonator 2, the other on the side of the outer end of the second resonator 3, and the restrictive-separation coil 11 is installed between the resonators.

Each of the first I / O 4 and the second I / O 5 of each of the resonators 2, 3 passes through its corresponding hole in the wall of the housing 1 and is isolated from the housing 1 by means of a dielectric sleeve 12. Dielectric bushings 12 and O-rings 8, 9 ensure tightness the internal gas-filled cavity of the high-frequency probe, limited by the housing 1, the dielectric tube 6 and the centering clips 7. Sealing the internal cavity makes it possible to avoid the effects of moist outside air on workers lementy resonators 2, 3, leading to a reduction in the Q factor.

The scan of each of the short-circuited conductors of each of the resonators 2, 3 has the shape of a rectangular meander (see Figure 2 and Figure 3); Electrotechnical copper may be selected as the material of the zigzag conductor.

The choice for a short-circuited conductor of rectangular cross section, the width of which significantly exceeds its thickness b:

a / b >> 1,

makes it possible to significantly reduce the electrical capacitive coupling between adjacent parallel sections of this conductor and thereby significantly increase the quality factor of the resonator.

The thickness of the cross section b of the short-circuited conductor of each resonator is selected taking into account the depth of penetration of an electromagnetic wave with a frequency F _max into the material of this conductor with specific conductivity σ:

where b is the thickness of the cross section of a shorted conductor of the resonator;

C is the speed of light;

F _max - the upper limit of the frequency of excitation of the resonators in the high frequency range;

K - dimensional coefficient of proportionality:

in which the electrical conductivity σ can be chosen equal to the electrical conductivity of copper.

The width a of the cross section of the short-circuited conductor of each resonator from the conditions of mirror symmetry is equal to the distance d between two adjacent parallel sections of this conductor directed along the longitudinal axis OO (see Figure 3):

a = d

and limited by empirically derived double inequality

10b≥a≥5b,

where b is the thickness of the cross section of a shorted conductor of the resonator;

and - the cross-sectional width of the short-circuited resonator conductor, providing in the entire RF range from the minimum value of F _min to the maximum value of F _{max a} compromise condition for minimizing the electrical capacitive bonds between the longitudinal parallel sections of the said conductor with a maximum density of the number of these sections on the outer surface of the dielectric pipe 6.

Restrictive and restrictive-separation coils 10 and 11, respectively, are used in the proposed system with the aim of shielding the electromagnetic field of the resonators.

Short-circuited coils of resonators, restrictive and restrictive-dividing coils are made by a method that ensures their mutual identity, for example, by photo-printing a scan pattern of a zigzag conductor of each of the resonators 2, 3 and each of the turns 10, 11 on a common resonator for all 2, 3 and turns 10 11 of the metal surface of the metal-foiled flexible dielectric substrate 13 with a width of 2πR (see FIG. 2). After the electrochemical treatment of the indicated metal surface, the dielectric substrate 13 with the sweeps of the zigzag conductors of the resonators 2, 3 and the turns 10, 11 formed on it is installed with the dielectric layer inward on the outer cylindrical surface of the dielectric pipe 6 and fixed to it, and the connection points n _{i of} each of the zigzag conductors each resonator 2, 3 and each of the turns 10, 11 are galvanically connected to their respective connection points m _i so that each of the points the connection thread n _i corresponded to only one connection point m _i , where i = 1, 2, ... 5 is the serial number of the connection point.

It should be noted that the location of the zigzag conductors of the resonators 2, 3 and turns 10, 11 on the common dielectric tube 6 inside the common housing 1 provides not only the axial symmetry of the resonators 2, 3, but also strict fixation of the distance L _o between the geometric centers of the first and the second resonators 2, 3, which is important, since the value of the center-to-center distance L _{o is} used in the algorithms for calculating the speed W of the controlled flow as a constant base value stored in the memory of the computing and control unit 20 values, and the constancy of the value of L _o is a necessary condition for ensuring the accuracy of measurements.

It should also be noted that the replacement of a separate input and a separate output of a known system resonator with a single resonator input-output proposed in the claimed system makes it possible to galvanically connect each of the first input-output 4 and each of the second input-output 5 to the corresponding resonator 2, 3 only at one point of its short-circuited conductor, which ensures complete mutual identity of the input and output impedances of each of the mentioned inputs / outputs.

For comparison, in the known system, the input impedance is inevitably different from the output, since each input and each output of each of the resonators of this system is galvanically connected to the corresponding short-circuited conductor at its two geometrically distinct points, which causes an additional measurement error.

In the dielectric tube 6 is installed a pressure sensor 14 of the controlled medium.

The flowmeter is a mass Coriolis flowmeter 15 containing a casing with flanges at its ends, one of which is designed to connect the casing to an external oil pipeline, and the other to the flange of the housing 1. The Coriolis flowmeter is equipped with two electronic transducers: an electronic flow transducer 16 and an electronic density transducer 17. The housing 1 and the Coriolis flowmeter 15 are interconnected using fasteners 18 through the sealing gasket 19.

The electronic measuring and computing device comprises a computing and control unit 20, a controlled high-frequency generator 21, a controlled switch 22, a mode controller 23, the first and second calibration controllers 24 and 25, respectively, the first and second input amplifiers 26 and 27, respectively, four input 33 and four output isolation capacitors 34, as well as the first two transmission paths 28 and two second transmission paths 29, each of these transmission paths comprising sequentially connecting interconnected output amplifier 30, the input of which serves as the input of this path, the amplitude detector 31 and the analog-to-digital converter 32, the output of which serves as the output of this path. If necessary, the proposed system can interact with external systems 35.

Input isolation capacitors 33 and output isolation capacitors 34 are required to connect each of the first I / O 4 and each of the second I / O 5 of the resonators 2 and 3 to two functionally different circuits:

- through the input isolation capacitor 33 - to the excitation circuits of the resonators 2 or 3, each of which contains the first or second input amplifier 26 or 27, a controlled switch 22 and a controlled high-frequency generator 21,

- through the output isolation capacitor 34 - to the measuring and computing circuits, each of which contains one of the first or second transmitting paths 28 or 29 and the computing and control unit 20.

In addition, each of the outputs of each of the transmission paths 28, 29 is connected to one of the corresponding inputs of the mode controller 23.

The output of the mode controller 23 is connected to the corresponding input of the computing and control unit 20 and, in addition, to one of the inputs of the first calibration controller 24, the other input of which is connected to the output of the electronic flow transducer 16. The output of the mode controller 23 is also connected to one of the inputs a second calibration controller 25, the other input of which is connected to the output of the electronic density transducer 17.

One of the outputs of the computing and control unit 20 is connected to the input of the controlled high-frequency generator 21, and the other output of this unit is connected to the control input of the managed switch 22.

The managed switch 22 contains two outputs, the first of which is connected through the first input amplifier 26 to each of the first I / O 4 of the resonators 2 and 3 through one of the input isolation capacitors 33 corresponding to this first I / O, and the second output through the second input amplifier 27 connected to each of the second input-output 5 of the resonators 2 and 3 through one of the input isolation capacitors 33 corresponding to this second input-output.

The output of the pressure sensor 14 is connected to one of the inputs of the mode controller 23, as well as to one of the inputs of the computing and control unit 20, which, if necessary, exchange information with external systems 35, interacts with them through the communication line.

The proposed system for measuring the mass flow rate of components of a gas-liquid flow of oil wells works as follows.

If there is a controlled gas-liquid medium moving at a speed W in the dielectric tube 6 and the Coriolis flowmeter 15, a start command is sent to the computing-control unit 20, which arrives at this unit, for example, from external systems 35 via an information exchange line.

The work of the computing-control unit consists of three sequentially performed stages: the first stage - the stage of determining the relative volume fractions V ₁ , V ₂ , V _{3 of} each of the three components of the controlled medium, the second stage - the stage of determining the speed W and component-wise volume flow Q ₁ , Q ₂ , Q _{3 of the} controlled environment, as well as the third stage - the stage of determining the component-wise mass flow rate Q _m1 , Q _m2 , Q _m3 .

At the beginning of the first stage, the computing-control unit 20 generates a start command received at the input of a controlled high-frequency generator 21.

In accordance with the adopted command, said generator generates a high-frequency signal with a frequency that varies smoothly over time, increasing in the RF range from the minimum value F _min to the maximum value F _max . The specified signal is necessary for the excitation of a high-frequency electromagnetic field in each of the resonators 2, 3 of the proposed system, designed, firstly, to obtain information about the relative volume fractions V ₁ , V ₂ and V _{3 of} each of the three components of the controlled medium and, secondly , - to obtain information about the value of the speed W of the controlled flow.

In the first step of the first stage, the signal generated by the controlled high-frequency generator 21 is fed to the input of the managed switch 22 and transmitted from one of the outputs of this switch through the first input amplifier 26 to the first input-output 4 of the first resonator 2 through the input isolation capacitor corresponding to this input-output 33 and to the first input-output 4 of the second resonator 3 through the input isolation capacitor 33 corresponding to this input-output, exciting in each of the resonators 2, 3 a high-frequency electromagnetic field ranging from F _min to F _max frequency.

Since in the dielectric tube 6 there is a three-component gas-liquid medium, each of the three components of which is characterized by certain values of the complex dielectric constant ε _j ^* and the complex electrical conductivity σ _j ^* , where j = 1, 2, 3 is the number of the medium component, when high-frequency electromagnetic field in each of the resonators 2, 3 will be absorbed by the medium controlled by the electromagnetic field energy at several resonant frequencies F _res1 , F _res2 and F _res3 , respectively.

Since the informative parameters of signals characterizing resonant absorption, such as, for example,

- the amplitudes of the output signals at the first, second and third resonant frequencies I _res1 , I _res2 and I _res3 , respectively,

- the transmission coefficients of the signals at the first, second and third resonant frequencies D _pe1 , D _res2 and D _pe3 , respectively, and

- resonant frequencies F _res1 F _res2 , F _res3 ,

significantly depend on the complex characteristics of the controlled medium ε ₁ ^* , ε ₂ ^* and ε ₃ ^* and σ ₁ ^* , σ ₂ ^* , σ ₃ ^* , each of the output signals of the first and second resonators 2 and 3, respectively, contains information about component composition of a gas-liquid stream.

These signals come from each of the first I / O 4 of the resonators 2, 3 through the output isolation capacitor 34 corresponding to this first I / O 4 and the first transmitting path 28 corresponding to this first I / O 4 to the first transmitting I / O 4 and the first transmitting path 28 input of the computing control unit 20 and the input of the mode controller 23.

In the second step of the first stage, the computing-control unit 20 generates a signal supplied to the control input of the managed switch 22 and causes the high-frequency signal of the controlled high-frequency generator 21 to switch from the first output of the managed switch 22 to its second output, after which the above procedure is repeated when the direction of high-frequency sounding is changed 90 °.

To change the direction of sensing, a high-frequency signal from the second output of the managed switch 22 is supplied to each of the second I / O 5 of each of the resonators 2, 3 through the second input amplifier 27 and the input isolation capacitor 33 corresponding to this second input / output, exciting in the resonators 2 and 3 high-frequency electromagnetic field, the direction of the intensity vector of which is perpendicular to the original.

This makes it possible to refine the high-frequency sounding of the controlled medium in the direction orthogonal to the original and to obtain significant additional information with respect to the initial information on the component composition of the non-axisymmetric gas-liquid flow.

The output signals, containing informative parameters depending on the component composition of the stream, are supplied from each of the second inputs / outputs 5 of each of the resonators 2, 3 through the output isolation capacitor 34 and the corresponding second transmission path 29 to the input, corresponding to this second input / output 5 the computing and control unit 20 and the input of the mode controller 23. In the mode controller 23, taking into account the signals about the pressure value P of the controlled medium coming from the output of the pressure sensor 14, preliminary assifikatsionny analysis informative parameters of the signals received from the first and second input-output 4 and 5 both resonators for two mutually orthogonal directions controlled flow sensing.

The purpose of this analysis is to preliminarily assign the flow regimes of the controlled flow to one of the “steady-state” and “unsteady” modes, with the subsequent final selection of one of the sub-modes, for example, the sub-mode: “steady-oil”, “steady-water”, “steady-gas "," Steady-oil-water "," steady-oil-gas "," steady-gas-water "," steady-oil-water-gas ", or" transient-oil-water "," transient-oil-water gas "etc. and generating a code signal corresponding to the selected sub mode. The generated code signal is supplied from the output of the mode controller 23 to the corresponding input of the computing and control unit 20, in the memory of which from the group of algorithms "Component Control" an algorithm is selected that corresponds to the received submode code.

The processing in the computing-control unit 20 of information on the relative volume content of the components of the controlled environment is carried out in accordance with a specific algorithm that corresponds to the actually established mode of the controlled flow, and therefore can be performed with high performance and minimal operating time of the unit 20 at a computational speed that allows tracking in real time, rapid changes in incoming information corresponding to a substantially unsteady flow, and thereby eliminate the error caused by the delay in the algorithmic processing of measurement results with rapid changes in the nature of the flow.

In accordance with the selected specific algorithm, the informative signals coming from each of the first and from each of the second inputs and outputs 4 and 5 of the resonators 2, 3 are compared and analyzed in the computing-control unit 20, and the values of the relative volume fractions V ₁ , V ₂ are calculated and V _{3 of} each of the three components of the controlled environment.

In the second stage of operation of the computing and control unit 20, the speed W of the controlled flow is determined.

To determine the speed W of the controlled medium in the proposed system, the autocorrelation method is selected. In this case, depending on the controlled flow mode detected by the controller 23, information on either the motion of the local inhomogeneity of the flow or the motion of the local feature of the flow can be used to determine the speed.

A local flow feature is understood to mean a local change in the properties of an almost uniform steady flow, such as, for example, local axial asymmetry of a flow, local helical swirl of a flow, concentrated helicoid swirl of a flow, local turbulence, etc. changes.

In the first case, when the mode unsteady flow mode is determined by the mode controller 23, information on the motion of the local inhomogeneity of the flow is used to determine the speed. Moreover, the previously described informative signals arriving at the input of the computing and control unit 20 from the first I / O 4 and the second I / O 5 of the first and second resonators 2 and 3 are continuously recorded in the memory of the specified block in the form of temporary implementations of each of these signals.

As temporary implementations of the informative signals of the resonators 2 and 3, for example, the dependences of the signal amplitudes on time t can be used: I _re1 (t), _Ires2 (t); I _res3 (t) near the previously mentioned first, second and third resonant frequencies F _res1 , F _res2 , F _res3, respectively.

Taking into account the specific sub-mode of the essentially unsteady flow defined by the mode controller 23, in the computing-control unit 20 from the group of algorithms “Speed control” an algorithm is selected that corresponds to the code of this sub-mode and, in accordance with the selected algorithm, the above-mentioned temporary realizations of informative signals generated in each of the resonators 2 and 3 and received on their inputs and outputs 4, 5.

After processing the temporary realizations, their mutual correlation function is determined and a time offset t of one of the implementations relative to the other is carried out, up to the maximum of the mutual correlation function.

When the maximum of the cross-correlation function is obtained in the course of the bias of the indicated realizations, the travel time Δτ is determined by the stable fluctuation of the component composition of the controlled flow of the above center-to-center distance L _o taken as the base length in the computing and control unit 20.

The speed W of the controlled medium is calculated in accordance with the expression

W = L _o / Δτ,

where L _o is the base length equal to the axial distance between the geometric centers of the first and second resonators 2 and 3, respectively.

The obtained value of the speed W is used in the computing and control unit 20 to calculate the component-wise volumetric flow rates Q ₁ , Q ₂ , Q _{3 of} each of the three components of the gas-liquid flow.

In the second case, when the steady state homogeneous flow motion is detected by the mode controller 23, in which there are no local, pronounced fluctuations in the component composition in the controlled medium, the determination of the velocity W by the method described above is unreliable. In this mode, as a reliably detected flow feature in the proposed system, not a local fluctuation of the component composition of the flow is used, but a local flow feature characterized by a significantly different ratio of the informative signals of resonators 2 and 3 obtained from mutually orthogonal radio wave sounding of the controlled medium.

The method of mutually orthogonal sounding allows us to record not only the motion of local inhomogeneities, but also the motion of the local features of the controlled flow, which are not fundamentally detected during uniformly directed sounding.

When the controller determines 23 the steady state flow of a homogeneous controlled flow in this controller, a code signal corresponding to the specified submode is generated and transmitted to the computing and control unit 20, and from the group of "Speed control" algorithms stored in the memory of block 20, an algorithm is selected that corresponds to the received code .

In accordance with the selected algorithm, time realizations are processed of the ratio of the value of the signal generated at the first input-output 4 of the first resonator 2 to the value of the signal generated at the second input-output 5 of the same resonator, as well as the ratio of the value of the signal generated at the first input- output 4 of the second resonator 3, to the magnitude of the signal generated at the second input-output 5 of this resonator.

After processing the indicated, significantly different from the average value, ratios of the signal values in the control unit, the mutual correlation function of their time realizations is determined, as in the previous case, and the time interval Δτ of the implementation bias is found at which this function experiences a maximum. As with a substantially unsteady flow, this period is equal to the time during which the local flow feature, characterized by a significantly different ratio of the signals received during mutually orthogonal sounding of the controlled medium, runs through the base length L _o .

The speed of the controlled flow in this case, as before, is

W = L _o / Δτ.

The found values of the velocity W and the relative volume fractions V ₁ , V ₂ and V _{3 of the} components of the controlled medium allow us to calculate the component-by-volume flow rate Q ₁ , Q ₂ , Q _{3 of} each of the three components of the gas-liquid flow:

Q ₁ = SWV ₁ , Q ₂ = SWV ₂ , Q ₃ = SWV ₃ ,

where S = πR ² is the area of the bore of the dielectric pipe 6.

During the third stage of operation of the computing and control unit 20, the component-by-mass flow rate Q _m1 , Q _m2 , Q _{m3 of} each of the three components of the gas-liquid flow is determined. At this stage, in addition to the above procedures, calculations are carried out that take into account data on the nominal density values ρ ₁ , ρ ₂ , ρ _{3 of} each of the three components of the controlled medium stored in the memory of the computing and control unit 20, signals about the pressure value P of the controlled medium, received at the corresponding inputs of the computing and control unit 20 from the output of the pressure sensor 14, as well as signals about the actual values of the mass flow rate Q _m and density ρ of the controlled medium, directly measured Coriolis flow meter 15 and received at the corresponding inputs of this unit from the output of the electronic flow transducer 16 through the first calibration controller 24 and from the output of the electronic density transducer 17 through the second calibration controller 25.

Data on the pressure value P of the controlled medium, as well as on the nominal density values ρ ₁ , ρ ₂ , ρ _{3 of} each of its components, are necessary for a rough estimate of the component-by-mass flow rate performed in the computing and control unit 20 with errors of indirect calculation of the density and mass flow rate of the components .

To accurately determine the component-by-mass flow rate, indirect data on the density of the components are insufficient; to refine these data, the results of direct measurement of the actual values of the density ρ and the mass flow rate Q _{m of the} controlled medium using a Coriolis flowmeter, the output information of which is adjusted in calibration controllers 24, 25 depending on from the flow regime of gas-liquid flow.

Correction of the readings of the Coriolis flowmeter is necessary due to the fact that the peculiarity of its operation is the presence of errors in the measurement of mass flow rate Q _m and density ρ arising from the heterogeneity of the controlled flow.

The nominal calibration characteristic (or nominal calibration) of the Coriolis flowmeter corresponds to a homogeneous flow of the controlled medium, the density of which is the same at all points of the cross section of the flow.

In the case where the density distribution over the flow cross section is not uniform, typical for most oil wells, the actual calibration of the Coriolis flowmeter does not correspond to the nominal calibration, which causes significant additional errors in measuring the mass flow rate Q _m and density ρ of the controlled medium.

To eliminate this error, the proposed system introduced the first and second calibration controllers 24 and 25, respectively, each of which stores data obtained during the calibration of the Coriolis flowmeter on a test calibration bench for several different flow regimes of the controlled flow.

During calibration tests of the Coriolis flowmeter, for each of the specified flow regimes, calibration families corresponding to this mode are obtained: a family of mass flow calibrations and a family of density calibrations, the data of which are stored in the memory of their respective controllers; flow calibration data to the memory of the first calibration controller 24, and density calibration data to the memory of the second calibration controller 25.

If at one of the inputs of the corresponding calibration controller 24 and 25 there is information about the mass flow rate Q _m coming from the output of the electronic flow transducer 16 and information about the density ρ coming from the output of the electronic density transducer 17, the received information is processed in each of these controllers values of Q _m and ρ code signal based on the actual flow conditions, was admitted to the other input of the corresponding calibration controller 24, the controller 25 outputs mode 23. In accordance with the received code signal in the calibration of the controller is stored in the memory of calibrations family selects one that corresponds to the actual flow regime. According to the selected calibration in each of the controllers 24, 25, the correction of the information received by this controller is performed. The corrected accurate information on the mass flow rate Q _m and density ρ of the controlled medium is transmitted from the output of each of the calibration controllers 24, 25 to the input of the computing and control unit 20 corresponding to this output, where, taking into account the data obtained in the first and second stages of operation of this unit, the final calculation of the exact and reliable values of the component mass flow rate Q _m1 , Q _m2 , Q _{m3 of} each of the three components of the gas-liquid medium.

Thus, the task of the proposed invention, which consists in increasing the accuracy and reliability of measuring the component mass flow rate, is solved by using the following new technical solutions in the proposed system: firstly, by determining the actual flow pattern in the mode controller 23 and taking into account this mode when determining reliable values of Q _m1 , Q _m2 and Q _m3 in the computing and control unit 20, and secondly, due to the use of two different directions of radio wave sensing of the controlled environment using two mutually orthogonal I / O 4, 5 connected to different outputs of the managed switch 22, and using the results of this sensing in the computing and control unit 20 and in the mode controller 23 to determine the exact values of Q _m1 , Q _m2 and Q _m3 and thirdly, by calibrating the readings of the Coriolis flowmeter 15 in terms of flow and density in the first and second controllers of calibrations 24 and 25, respectively, in order to determine accurate and reliable values of Q _m and ρ in the computing and control unit 20.

Claims (1)

A system for measuring the mass flow rate of components of a gas-liquid flow of oil wells, which includes a computing and control unit, the first high-frequency resonator in the form of a short-circuited conductor having the shape of a rectangular meander placed on the outer cylindrical surface of the dielectric pipe located inside the tubular body coaxially with it, a flow meter equipped with electronic flow transducer and located in series with the first high-frequency resonator mounted in a diel electric tube pressure sensor, the output of which is connected to the corresponding input of the computing and control unit, a controlled high-frequency generator, a first input amplifier, a transmitting path, which is a series-connected output amplifier, the input of which is the input of this transmitting path, an amplitude detector and an analog-to-digital converter, the output of which serves as the output of this path, and the first high-frequency resonator is connected through the transmitting path to the corresponding input control and control unit, the output of which is connected to the input of a controlled high-frequency generator, and through the first input amplifier this high-frequency resonator is connected to a controlled high-frequency generator, characterized in that according to the invention, a second high-frequency resonator is added to it, identical to the first and placed coaxially with it dielectric tube inside the said housing, each of the high-frequency resonators is equipped with a first input-output and a second input-output, and The first input-output and the second input-output of each high-frequency resonator lie in diametric mutually perpendicular planes, a Coriolis flowmeter, additionally equipped with an electronic density transducer, is used as a flowmeter, the system further comprises a second input amplifier, a mode controller, and a controllable switch connected to the output of the controlled high-frequency generator equipped with an input, a control input and two outputs, one of which is connected to the first input amplifier, the other - with a second input amplifier, and the control input with the corresponding output of the computing and control unit, the output of the transmitting path is additionally connected to the corresponding input of the mode controller, in addition, the system additionally contains four input isolation capacitors and four output isolation capacitors, three transmitting paths that are identical said transmitting path, wherein the output of each of these three transmitting paths is connected to one of the corresponding inputs of the computing and control unit In addition to one of the corresponding inputs of the mode controller, the system further comprises a first calibration controller, one of whose inputs is connected to the output of the electronic flow transducer, and a second calibration controller, one of whose inputs is connected to the output of the electronic density transducer, and the output each of these controllers is connected to one of the corresponding inputs of the computer-control unit, the first or second input-output of each high-frequency resonator is connected to the input of only one of the transmission paths through one of the output isolation capacitors, in addition, each of the first inputs / outputs of each high-frequency resonator is connected to the output of the first input amplifier through one of the input isolation capacitors, and each of the second inputs and outputs of each high-frequency resonator is through one of the input isolation capacitors connected to the output of the second input amplifier, the output of the pressure sensor is additionally connected to the corresponding input of the mode controller, while the output the mode controller is connected to the corresponding input of the computing and control unit and, in addition, to the corresponding input of the first and to the corresponding input of the second calibration controller, in addition, a limit loop is installed at the end sections of the dielectric tube, and a limit-between the first and second high-frequency resonators dividing coil, limiting turns, limiting-dividing coil and short-circuited conductors of each high-frequency resonator have a rectangle Flax cross-sectional thickness b cross section of each short-circuit conductor of each high-frequency resonator, limiting each coil and separating the coil-restrictively defined by the inequality

, where K is the dimensional coefficient of proportionality; F _max - the upper limit of the frequency of the signal at the output of a controlled high-frequency generator, the width a of the cross section of each short-circuited conductor of each high-frequency resonator is equal to the distance d between two adjacent parallel, directed along the longitudinal axis sections of this conductor and is limited by the double inequality 10b≥a≥5b.

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