CN111289579A - An integrated sensor and water holdup correction method based on land surface gas-liquid separation - Google Patents

Abstract

The invention provides a land-based gas-liquid separation integrated sensor and a water holding capacity correction method, wherein the integrated sensor comprises a coaxially arranged electric conduction type sensor module, a capacitance sensor module and an array optical fiber sensor module; the capacitance sensor module is respectively provided with a metal shell, an outer insulating cylinder, a metal layer and an inner insulating cylinder from outside to inside; an insulating rod is arranged in the center of the capacitive sensor module, the conductive sensor module is positioned at one end of the insulating rod, and the conductive sensor module comprises six electrode rings; the array optical fiber sensor module is fixed at the other end of the insulating rod and comprises array optical fiber probes, measuring points of all the optical fiber probes are located on the same cross section, and the cross section is the radial cross section of the capacitance sensor module. The technical scheme of the invention solves the technical problems of incomplete gas phase separation, large error and the like in the existing land surface gas-liquid separation water holdup monitoring mode.

Description

An integrated sensor and water holdup correction method based on land surface gas-liquid separation

technical field

The invention relates to the technical field of oil well monitoring, in particular, to an integrated sensor based on land surface gas-liquid separation and a water holdup correction method.

Background technique

In the current field of multiphase flow, there are three main ways to monitor the parameters of land oil fields, including two-phase separation and three-component measurement, three-phase separation measurement, and non-separation measurement. Due to the long distance between my country's oilfield metering operation areas, the field distribution of oilfield oil wells is scattered and chaotic, and the number is huge. The three-phase separation measurement is large in size and complicated in operation; the non-separation measurement mode has the characteristics of small size and light weight, but the technical cost is extremely expensive, so it is not suitable for large-scale promotion of domestic oil well monitoring. Compared with the three-component measurement and non-separation measurement, the gas-liquid separation component monitoring technology is the main monitoring mode of the current land oil field parameter monitoring mode due to its simple technical principle, relatively small volume and low cost. means.

The electrical method is widely used in the field of oil-water two-phase flow monitoring due to its simple structure, low cost and fast response speed. The electrical method mainly includes the conductometric method and the capacitive method. Due to the obvious differences in the conductivity and dielectric properties of the oil-water two-phase flow, the capacitive and conductivity sensing technology has achieved good application in the oil-water two-phase flow phase holdup measurement. Fiber-optic probe technology is widely used in gas-liquid two-phase flow holdup monitoring because it is only sensitive to the gas phase. However, the fiber optic probe technology has the limitations of single parameter measurement and low interface coverage. Although the conductivity and capacitance phase holdup monitoring method of land oil wells is widely used in parameter monitoring in the field of oil-water two-phase flow, it ignores the oil-water two-phase flow. The influence of the free gas in the phase flow fluid on the monitoring accuracy, and the error of the measurement accuracy.

It can be seen that, in order to meet the actual requirements of oilfield production, it is urgent to research a new equipment and method that can accurately monitor and correct phase holdup in oil production logging.

SUMMARY OF THE INVENTION

According to the above technical problems such as incomplete gas phase separation and large error in the existing land surface gas-liquid separation water holdup monitoring mode, an integrated sensor and water holdup correction method based on land surface gas-liquid separation are provided. The invention can realize the accurate and real-time measurement of the water holdup in the case of incomplete gas-liquid separation in the land surface gas-liquid separation type water holdup monitoring technology.

The technical means adopted in the present invention are as follows:

The invention provides an integrated sensor based on land surface gas-liquid separation, which is characterized by comprising a coaxially arranged conductance sensor module, a capacitance sensor module and an array optical fiber sensor module;

The capacitive sensor module is respectively a metal casing, an outer insulating cylinder, a metal layer and an inner insulating cylinder from the outside to the inside;

An insulating rod is arranged in the center of the capacitive sensor module, the conductance sensor module is located at one end of the insulating rod, and the conductance sensor module includes six electrode rings;

The array fiber optic sensor module is fixed on the other end of the insulating rod, and the array fiber optic sensor module includes an array fiber optic probe, and the array fiber optic probe is located between the insulating rod and the inner insulating cylinder. In the gap, the arrayed fiber probe includes several fiber probes, and the measurement points of all the fiber probes are located in the same section, and the section is the radial section of the capacitive sensor module;

The gap between the insulating rod and the inner insulating cylinder is divided into n layers of annular space, and the cross-section is divided into m sector-shaped areas with a central angle of 360/m based on the center of the cross-section. The measurement points of the probe are all located on the separation line of the fan-shaped area, and there are m/2 measurement points of the optical fiber probe in each annular space, and two adjacent optical fiber probes in the annular space of the same layer. The angle formed between the measurement point of the needle and the center of the section is 180/m, and the total number of measurement points of the optical fiber probe in the adjacent two-layer annular space is m; the total number of the optical fiber probe is (m/2)×n; where n≥1, n∈N ^* ; m≥1, m∈N ^* .

The present invention also proposes a low-gas-volume oil-water water-holding correction method based on land-surface gas-liquid separation, which adopts the above-mentioned integrated sensor, and includes the following processes:

The capacitance sensor module is used to measure the water holdup of the oil-water two-phase flow containing a trace gas phase after the gas-liquid separation process, and the capacitance water holdup h _c is obtained according to the capacitance signal;

The conductance sensor module is used to monitor the oil-water two-phase flow containing a trace gas phase after the gas-liquid separation process, and the conductance water _holdup hi and the flow rate f are obtained according to the conductance signal;

The array optical fiber sensor module is used to monitor the oil-water two-phase flow containing trace gas phase after gas-liquid separation treatment, and an image processing method is used to obtain the estimated value of the cross-sectional gas holdup h _g ;

Taking the capacitance water holdup h _c and the electrical conductivity water _holdup hi as the information source, the fusion water holdup h _m is obtained through data fusion;

h_w表示矫正后的持水率。Taking the fusion of water holdup h _m and cross-section gas holdup h _g as characteristic parameters, a water holdup correction model is constructed

h _w represents the corrected water holdup.

Further, the method for obtaining the estimated value of the cross-sectional gas holdup h _g adopted by the arrayed optical fiber sensor module specifically includes the following steps:

Step S1: the gap between the insulating rod and the inner insulating cylinder is divided into n layers of annular space;

Step S2: performing interpolation to increase the measurement points of the optical fiber probe in each layer of annular space to m, and the measurement points increased by interpolation are interpolation points;

Step S3: using the multi-nearest neighbor interpolation method to estimate the virtual data of the interpolation point, the virtual data estimation is performed according to the weighting of the neighbor points, the number of the neighbor points is set to m, and the selection rule of the neighbor points is: close to the actual measurement point with the closest distance to the interpolation point , and the neighbor point is located in the adjacent layer of the annular space where the interpolation point is located, and only one neighbor point is selected in each annular space; the multi-nearest neighbor interpolation rule of the interpolation point is Z _i =α ₁ Z ₁ +α ₂ Z ₂ +α ₃ Z ₃ +α ₄ Z ₄ , wherein Zi, Z1, Z2, Z3, and Z4 represent the voltage signals of the actual measurement points respectively; the weights α ₁ , α ₂ , α ₃ , α ₄ are based on the flow f obtained by the conductance sensor module select;

Step S4: imaging the response signals of the actual measurement point and the interpolation point;

Step S5: Perform regional identification on the imaged gas phase distribution pattern, and obtain cross-sectional gas holdup estimation information.

Compared with the prior art, the present invention has the following advantages:

The present invention provides an integrated sensor based on land-surface gas-liquid separation and a water holdup correction method. The integrated sensor includes a capacitance monitoring module, a conductance monitoring module, and an optical fiber monitoring module, and the whole presents a coaxial cylindrical shape; the water holdup correction method is based on The water holdup correction model is established by integrating the water holdup characteristics, flow characteristics and gas holdup characteristics; it overcomes the defects of incomplete gas phase separation and large errors in the water holdup monitoring mode of land surface gas-liquid separation.

In conclusion, the application of the technical solution of the present invention can realize accurate and real-time measurement of water holdup in the case of incomplete gas-liquid separation in the land-surface gas-liquid separation water holdup monitoring technology. Therefore, the technical solution of the present invention solves the problems of incomplete gas phase separation and large errors in the existing land surface gas-liquid separation water holdup monitoring mode.

Based on the above reasons, the present invention can be widely promoted in the fields of oil well monitoring and the like.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is a schematic diagram of the integrated sensor of the present invention.

FIG. 2 is a schematic cross-sectional view of the integrated sensor according to the present invention.

FIG. 3 is a schematic cross-sectional view of the integrated sensor according to the present invention.

FIG. 4 is a schematic diagram of the integrated sensor circuit system module based on gas-liquid separation according to the present invention.

Fig. 5 is the water holdup measurement system based on the land surface gas-liquid separation according to the present invention.

FIG. 6 is a flow chart of the water holdup correction method according to the present invention.

FIG. 7 is a flow chart of the gas holdup monitoring of the cross-section of the arrayed optical fiber probe according to the present invention.

In the figure: 1. Wellhead pipeline; 2. Solenoid valve No. 1; 3. Solenoid valve No. 2; 4. Solenoid valve No. 3; 5. Inlet pipeline; 6. Gas-liquid separation tank; 7. Exhaust equipment; 8. Integrated Sensor; 9. Outlet pipe; 10. Inner insulating layer; 11. Metal layer; 12. Outer insulating layer; 13. Metal shell; 14. Downstream fixing bracket; 15. Array fiber optic sensor module; 16. Conductivity sensor module; 17 , upstream fixing bracket; 18, insulating rod; 161, excitation E2 electrode ring; 162, measurement M4 electrode ring; 163, measurement M3 electrode ring; 164, measurement M2 electrode ring; 165, measurement M1 electrode ring; 166, excitation E1 electrode ring.

Detailed ways

It should be noted that the embodiments of the present invention and the features of the embodiments may be combined with each other under the condition of no conflict. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments It is only a part of the embodiments of the present invention, but not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

As shown in Figures 1-3, the present invention provides an integrated sensor based on land surface gas-liquid separation, which can realize accurate and real-time monitoring technology of water holdup based on land surface gas-liquid separation under the condition of incomplete gas-liquid separation. Measuring water holdup, including a coaxially arranged conductivity sensor module 16, a capacitive sensor module and an array fiber optic sensor module 15;

The capacitive sensor module 16 is respectively a metal casing 13, an outer insulating layer 12, a metal layer 11 and an inner insulating layer 10 from the outside to the inside;

An insulating rod 18 is arranged in the center of the capacitive sensor module, the conductance sensor module 16 is located at one end of the insulating rod 18, and the conductance sensor module 16 includes six electrode rings;

The arrayed optical fiber sensor module 15 is fixed on the other end of the insulating rod 18, and the arrayed optical fiber sensor module 15 includes an arrayed optical fiber probe, and the arrayed optical fiber probe is located in the insulating rod 18 and is insulated from the inner In the space between the layers 10, the arrayed fiber optic probe includes several fiber optic probes, and the measurement points of all the fiber optic probes are located in the same section, and the section is the radial section of the capacitive sensor module. ;

The gap between the insulating rod 18 and the inner insulating cylinder 10 is divided into n layers of annular space, and the cross-section is divided into m sector-shaped areas with a central angle of 360/m based on the center of the cross-section. The measurement points of the optical fiber probe are all located on the separation line of the fan-shaped area, and there are m/2 measurement points of the optical fiber probe in each annular space. The angle formed between the measurement point of the optical fiber probe and the center of the section is 180/m, and the total number of measurement points of the optical fiber probe in the adjacent two-layer annular space is m; The total is (m/2)×n; where n≥1, n∈N ^* ; m≥1, m∈N ^* .

Further, the insulating rod is fixed to the inner insulating layer 10 through the downstream fixing bracket 14 and the upstream fixing bracket 17 , and the insulating rod 18 , the downstream fixing bracket 14 and the upstream fixing bracket 17 are all insulated and corrosion-resistant. Material.

Further, the conductance sensor module 16 includes excitation E2 electrode ring 161 , measurement M4 electrode ring 162 , measurement M3 electrode ring 163 , measurement M2 electrode ring 164 , measurement M1 electrode ring 165 and excitation E1 electrode ring 166 .

Further, the outer wall of the insulating rod 18 has six recessed annular grooves arranged at equal intervals, and the six electrode rings of the conductance sensor module 16 are respectively embedded in the annular grooves.

Further, during operation, the metal layer 11 is connected to the capacitive excitation source, and the metal shell 13 is connected to the ground.

Preferably, in this embodiment, the gap between the insulating rod 18 and the inner insulating cylinder 10 is divided into four layers of annular spaces, and the cross-section is divided into a central angle of 45 with the center of the cross-section as the base point. 8 fan-shaped areas of °, the measurement points of the optical fiber probe are all located on the separation line of the fan-shaped area, and there are 4 measurement points of the optical fiber probe in each annular space, and in the same annular space, The angle formed between the measurement points of the two adjacent optical fiber probes in the same annular space and the center of the section is 90°, and the measurement points of the optical fiber probes in the adjacent two annular spaces The total number is 8; the total number of the fiber probes is (m/2)×n; where n≥1, n∈N ^* ; m≥1, m∈N ^* .

FIG. 4 is a schematic diagram of the working circuit of the integrated sensor based on land-surface gas-liquid separation. The conductance sensor module 16 includes a conductance sensor circuit subsystem, the capacitive sensor module includes a capacitive sensor circuit subsystem, and the The array optical fiber sensor module 15 includes an array optical fiber probe sensor circuit subsystem; the integrated sensor further includes a power supply module and a main control module.

The conductance sensor module 16 has two working modes, namely, a conductance related flow monitoring sensor and a conductance water holdup monitoring sensor. The main control module controls the working state of the conductance sensor module 16 and has two working modes. cannot be done simultaneously;

The conductance-related flow monitoring sensor includes:

The conductance-related excitation module is used to excite the excitation E2 electrode ring 161 and the excitation E1 electrode ring 166, to provide the conductance-related flow monitoring circuit module with an alternating current with a constant amplitude, and to establish a current field in the pipeline;

The downstream detection electrode composed of the measurement M3 electrode ring 163 and the measurement M4 electrode ring 162;

And, the upstream detection electrode composed of the measurement M1 electrode ring 165 and the measurement M2 electrode ring 164;

The upstream detection electrode and the downstream detection electrode are respectively connected to the upstream signal processing circuit and the downstream signal processing circuit. When the two-phase fluid flows through the integrated sensor, the random change of the fluid impedance produces a random modulation effect on the alternating constant current acting on the upstream detection electrode and the downstream detection electrode, and the output of the upstream detection electrode and the downstream detection electrode will follow the The modulation effect produces corresponding changes, and the upstream signal processing circuit and the downstream signal processing circuit perform corresponding operations such as amplification, detection, filtering, etc., to demodulate the fluid flow noise signals x(t) and y(t), and the noise signals are used for Calculate the flow f;

The conductivity water holdup monitoring sensor includes:

The conductance excitation module uses a waveform generator to generate a 20KHz excitation constant current source for excitation of the excitation E2 electrode ring 161 and the excitation E1 electrode ring 166;

Conductance signal processing module, including signal conditioning circuit, voltage-frequency conversion circuit and signal shaping circuit, is used for conditioning, voltage-frequency conversion, pulse-width modulation and other processing on the voltage signals measured by M3 electrode ring 163 and M2 electrode ring 164, and output Frequency signal reflecting water holdup information.

The capacitive sensor circuit subsystem includes a capacitive excitation module and a capacitive signal processing module. The capacitive excitation module generates an excitation source from an oscillation circuit to excite the capacitive sensor module, and the capacitive signal processing module is used to perform signal processing on the capacitive sensor module. Processing; on the one hand, the capacitance excitation module measures the capacitance of the capacitance sensor, and on the other hand, it directly outputs a frequency signal that can reflect the capacitance of the capacitance sensor. The capacitance signal processing module only performs signal shaping and filtering, and the whole process of the measurement of the capacitance sensor does not The voltage signal, the direct output of the excitation module is the frequency signal, so the capacitance signal processed by the main controller module is also a frequency signal, and the level of the frequency reflects the capacitance of the capacitance sensor.

The array optical fiber detection sensor circuit subsystem includes a light emitting module, a light receiving module, and a signal processing module. The light emitting module is used to provide driving power for the infrared light source, so that the infrared light source emits light; the light receiving module is used for the detector to The returned light energy is converted into electrical energy; the signal processing module performs differential, power amplification, analog-to-digital conversion and other operations on the received electrical signal, and outputs a voltage signal reflecting the gas holdup information;

the power module is used to supply power to the integrated sensor;

The main controller control module is used to control the working mode of the conductance sensor module 16, obtain flow and water holdup information at the same time according to the frequency signal; calculate the water holdup according to the frequency signal processed by the capacitance signal processing module; The voltage signal of the fiber optic probe was imaged, and the cross-sectional gas holdup was calculated.

During operation, after gas-liquid separation, the water holdup measurement of the oil-water two-phase flow is carried out. First, the conductivity sensor module 16 is adjusted to the operating mode of the conductivity water holdup monitoring sensor, and the whole water phase of the oil-water two-phase flow is calibrated, that is, The conductivity water holdup monitoring sensor is calibrated. Under the condition that water is a continuous phase, the voltage amplitude between the measuring electrodes M2 and M3 is inversely proportional to the conductivity of the fluid passing through the conductivity water holdup monitoring sensor. Let the conductance of the measuring electrodes M2 and M3 be G _m when the oil and water are mixed, and G _w when the water is full, the conductivity of the mixed phase is σ _m , the conductivity of water is σ _w , and the output frequency of the sensor is F _m when the mixed phase is mixed. value), the total water value is F _w (total water value), then

The ratio of σ _m to σ _w is given by Maxwell's formula:

In the formula, β is the volume fraction of the continuous conductive phase in the two-phase flow, which is the conductivity water _holdup hi in the oil-water two-phase flow.

The water holdup refers to the volume percentage of the water phase in a certain part of the wellbore. The ratio of the total water value to the miscible phase value in formula (2) is called the relative response of the instrument. The miscible phase value is measured when the oil-water two-phase fluid flows through the sensor, The total water value can be obtained by connecting a sampler under the sensor to the oil-water two-phase separation.

Then, the conductance sensor module 16 is adjusted to the working mode of the conductance-related flow monitoring sensor, and the cross-correlation operation is performed on the two flow noise signals. The cross-correlation function is expressed as:

τ refers to the time interval between the similar waveforms of the signals obtained by the upstream sensor and the downstream sensor, which is obtained based on the actual signal; the peak value of the cross-correlation function represents the maximum similarity of the two flow noise signals, and its corresponding time τ ₀ is the time elapsed by the fluid flow noise signal from upstream to downstream, called the transit time.

The flow f is:

f=(L/τ ₀ )*a _p (4)

In formula (4), L is the upstream and downstream distance, that is, the distance between the center of the electrodes M1 and M2 to the center of the electrodes M3 and M4, and a _p is the cross-sectional area of the conductance-related flow monitoring sensor pipeline.

The principle of the measurement part of the capacitance sensor module is to establish the relational expression (5) between the oil-water ratio and the capacitance to obtain the water holdup information. The capacitive excitation module is turned on to generate a capacitive excitation source to ensure the normal operation of the capacitive sensor; the capacitive signal processing module performs filtering and other processing on its frequency signal; when the capacitive sensor is placed in a full oil phase environment, the output frequency is F _co ; The output frequency is F _cw in the whole water phase environment; when the capacitance sensor is placed in the oil-water two-phase fluid to be measured, the output frequency is F _c , and the radius of the inner insulating layer of the capacitance sensor is set as R ₀ , and the inner diameter of the metal layer is R ₁ , the inner diameter of the outer insulating layer R ₃ , the inner diameter of the metal shell R ₂ , the relative permittivity of the insulating material is ε _r1 , the relative permittivity of the dielectric between the metal layer and the metal shell is ε _r2 , the relative permittivity of the oil phase is ε _oil , the relative permittivity of the water phase is ε _water , and the permittivity of the vacuum is ε ₀ ;

Determine the fluid water holdup by the fluid capacitance:

Among them, y _w in the above formula represents the capacitive water holdup h _c in the oil-water two-phase flow.

The array fiber optic sensor module 15 outputs a high-level voltage signal when the array fiber optic probe detects the gas phase medium when passing through the oil-water two-phase flow fluid containing trace gas phase; and outputs a low voltage signal when detecting the liquid phase medium. According to the different responses of the gas and liquid phases, the image processing method is used to obtain the estimated value of the cross-sectional gas holdup h _g .

As shown in Figure 5, the water holdup measurement system using the above-mentioned integrated sensor based on land surface gas-liquid separation includes wellhead pipeline 1, No. 1 solenoid valve 2, No. 2 solenoid valve 3, No. 3 solenoid valve 4, and inlet pipeline 5. , gas-liquid separation tank 6, exhaust equipment 7, integrated sensor 8 and outlet pipeline 9;

The inlet pipe 5 and the outlet pipe 9 are respectively connected to the wellhead pipe 1, and the number one is set at the position between the connection holes of the inlet pipe 5 and the outlet pipe 9 on the wellhead pipe 1. Solenoid valve 2, the No. 2 solenoid valve 3 and the No. 3 solenoid valve 4 are respectively set on the inlet pipe and the outlet pipe; the inlet pipe 5 is connected to the gas-liquid separation tank 6, and the integrated The sensor 8 is arranged inside the gas-liquid separation tank 6 , the integrated sensor 8 is communicated with the outlet pipeline, and the top of the gas-liquid separation tank 6 is arranged on the exhaust device 7 which is communicated with the outlet pipeline 9 . ;

When the water holdup measurement system does not work, the No. 2 solenoid valve 3 and the No. 3 solenoid valve 4 are closed, and the No. 1 solenoid valve 2 is opened; when the water holdup measurement system starts to work, The No. 2 solenoid valve 3 and the No. 3 solenoid valve 4 are opened, the No. 1 solenoid valve 2 is closed, the three-phase flow of oil, gas and water enters the gas-liquid separation tank 6 through the inlet pipe, and most of the gas is The exhaust device 7 is discharged into the outlet pipe 9, and the oil-water two-phase flow containing a trace gas phase enters the integrated sensor 8 from the gas-liquid separation tank 6 for water holdup measurement.

As shown in Figures 6-7, the present invention also provides a low gas volume oil-water water holdup correction method based on land surface gas-liquid separation, using the above integrated sensor, including the following processes:

The capacitance sensor module is used to measure the water holdup of the oil-water two-phase flow containing a trace gas phase after the gas-liquid separation process, and the capacitance water holdup h _c is obtained according to the capacitance signal;

The conductance sensor module is used to monitor the oil-water two-phase flow containing a trace gas phase after the gas-liquid separation process, and the conductance water _holdup hi and the flow rate f are obtained according to the conductance signal;

The array fiber optic sensor module is used to monitor the oil-water two-phase flow containing trace gas phase after gas-liquid separation treatment, and the estimated value of cross-section gas holdup h _g is obtained by image processing method; specifically, the multi-nearest neighbor interpolation imaging method and The area identification image processing method obtains the estimated value of the gas holdup h _g of the section;

Taking the capacitance water holdup h _c and the electrical conductivity water _holdup hi as the information source, the fusion water holdup h _m is obtained through data fusion;

h_w表示矫正后的持水率。Taking the fusion of water holdup h _m and cross-section gas holdup h _g as characteristic parameters, a water holdup correction model is constructed

h _w represents the corrected water holdup.

Further, the method for obtaining the estimated value of the cross-sectional gas holdup h _g adopted by the arrayed optical fiber sensor module specifically includes the following steps:

Step S1: the gap between the insulating rod and the inner insulating cylinder is divided into n layers of annular space;

Step S2: performing interpolation to increase the measurement points of the optical fiber probe in each layer of annular space to m, and the measurement points increased by interpolation are interpolation points;

Step S3: using the multi-nearest neighbor interpolation method to estimate the virtual data of the interpolation point, the virtual data estimation is performed according to the weighting of the neighbor points, and the result of the data estimation is estimated according to the response data of the interpolation point of the neighbor points; the number of the neighbor points is set to m , the selection rule of neighbor points is: close to the actual measurement point with the closest distance to the interpolation point, and the neighbor point is located in the adjacent layer of the annular space where the interpolation point is located, and only one neighbor point is selected in each annular space; the multi-nearest neighbor interpolation rule of the interpolation point is Z _i =α ₁ Z ₁ +α ₂ Z ₂ +α ₃ Z ₃ +α ₄ Z ₄ , wherein Zi, Z1, Z2, Z3, Z4 represent the voltage signals of the actual measurement points respectively; the weights α ₁ ,α ₂ , α ₃ , α ₄ are selected according to the flow rate f obtained by the conductance sensor module, the flow rate in the pipeline is different, and the distribution of the gas in the pipeline is different, and the weight is determined according to this difference;

Step S4: imaging the response signals of the actual measurement point and the interpolation point;

Step S5: Perform regional identification on the imaged gas phase distribution pattern, and obtain cross-sectional gas holdup estimation information.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be The technical solutions described in the foregoing embodiments are modified, or some or all of the technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (3)

1. A gas-liquid separation integrated sensor based on land is characterized by comprising a conductive sensor module, a capacitance sensor module and an array optical fiber sensor module which are coaxially arranged;

the capacitance sensor module is respectively provided with a metal shell, an outer insulating cylinder, a metal layer and an inner insulating cylinder from outside to inside;

an insulating rod is arranged in the center of the capacitive sensor module, the conductive sensor module is positioned at one end of the insulating rod, and the conductive sensor module comprises six electrode rings;

the array optical fiber sensor module is fixed at the other end of the insulating rod and comprises an array optical fiber probe which is positioned in a gap between the insulating rod and the inner insulating cylinder, the array optical fiber probe comprises a plurality of optical fiber probes, measuring points of all the optical fiber probes are positioned on the same cross section, and the cross section is a radial cross section of the capacitance sensor module;

a gap between the insulating rod and the inner insulating cylinder is divided into n layers of annular spaces, the cross section is divided into m fan-shaped areas with a central angle of 360/m by taking the center of the cross section as a base point, measuring points of the optical fiber probes are all positioned on a separation line of the fan-shaped areas, m/2 measuring points of the optical fiber probes are arranged in each layer of annular space, an included angle formed by the measuring points of two adjacent optical fiber probes in the same layer of annular space and the center of the cross section is 180/m, and the total number of the measuring points of the optical fiber probes in two adjacent layers of annular spaces is m; the total number of the optical fiber probes is (m/2) multiplied by n; wherein N is more than or equal to 1, N belongs to N^*；m≥1,m∈N^*。

2. A low-gas-volume oil-water retention correction method based on land gas-liquid separation, which adopts the integrated sensor of claim 1, and is characterized by comprising the following steps:

the capacitance sensor module is adopted to measure the water holding capacity of the oil-water two-phase flow containing trace gas phase after gas-liquid separation treatment, and the capacitance water holding capacity h is obtained according to capacitance signals_c；

Adopting the conductive sensor module to monitor the oil-water two-phase flow containing trace gas phase after gas-liquid separation treatment, and obtaining the conductive water holding rate h according to the conductive signal_iAnd a flow rate f;

the array optical fiber sensor module is adopted to monitor the oil-water two-phase flow containing trace gas phase after gas-liquid separation treatment, and an image processing method is adopted to obtain the section gas holdup h_gAn estimated value;

the water holding capacity h of the capacitor_cAnd the water holding rate h of electric conduction_iAs an information source, acquiring fusion water holdup h through data fusion_m；

Will fuse the water holdup h_mAnd section gas holdup h_gAs characteristic parameters, a water holding rate correction model is constructed

h_wIndicating the corrected water retention.

3. The land gas-liquid separation-based low-air-volume oil-water retention correction method according to claim 2, wherein the array type optical fiber sensor module adopts a method for obtaining a cross-sectional gas retention h_gThe method for estimating the value specifically comprises the following steps:

step S1: a gap between the insulating rod and the inner insulating cylinder is divided into n layers of annular spaces;

step S2: interpolating and increasing the number of the measurement points of the optical fiber probe in each layer of annular space to m, wherein the measurement points with increased interpolation are interpolation points;

step S3:virtual data estimation is carried out on the interpolation points by adopting a multi-neighbor interpolation method, the virtual data estimation is carried out according to the weighting of the neighbor points, the number of the neighbor points is set to be m, and the rule of selecting the neighbor points is as follows: the actual measurement point which is close to the interpolation point and has the nearest distance is positioned at the adjacent layer of the annular space where the interpolation point is positioned, and only one adjacent point is selected in each layer of annular space; the multi-neighbor interpolation rule of the interpolation point is Z_i＝α₁Z₁+α₂Z₂+α₃Z₃+α₄Z₄Wherein Zi, Z1, Z2, Z3 and Z4 represent voltage signals of actual measurement points respectively, and weight α₁,α₂,α₃,α₄Selecting according to the flow f obtained by the conductance sensor module;

step S4: imaging the response signals of the actual measurement point and the interpolation point;

step S5: and carrying out region identification on the imaged gas phase distribution graph to obtain section gas holdup estimation information.

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