Flow pattern and moisture content measurement device and method based on orthogonal microwave dual mode

Abstract

The present invention discloses a flow pattern and water content measurement device and method based on orthogonal microwave dual modes, which is applied in the field of crude oil and natural gas engineering. The present invention innovatively integrates a conformal antenna array unit (mode one) and an orthogonal microwave transmission line unit (mode two) to construct a dual-mode microwave sensor with dual complementary orthogonal microwave fields to achieve the measurement of dual parameters of flow pattern and water content. For the two typical flow patterns of stratified flow and annular flow, the microwave amplitude signals of the vertical and horizontal antenna pairs in mode one and the phase signals of the vertical and horizontal transmission lines in mode two are analyzed in relation to the change characteristics of the flow pattern and water content, a flow pattern identification method is proposed, and a water content measurement model is constructed. The present invention can predict the changes in the flow pattern and water content of two-phase flow in real time and with high precision online.

Description

Technical Field

[0001] The present invention belongs to the technical field of multiphase flow detection, and relates to a flow pattern and water content measurement device and method based on orthogonal microwave dual modes. Background Art

[0002] During the extraction and transportation of crude oil / natural gas, the two-phase flow pattern becomes complex due to the influence of the oil / gas reservoir structure and pipeline terrain conditions. In addition, the geological structure of oil / gas wells in different regions and the influence of secondary extraction water or steam injection cause salinity changes. These problems pose a huge challenge to the accurate real-time monitoring technology of oil-water / gas-water two-phase flow parameters, and effective solutions are urgently needed.

[0003] Currently, technologies for online prediction of two-phase flow patterns and water content include conductivity, ultrasound, X-ray, capacitance, and microwave methods. Microwave-based two-phase flow pattern and water content measurement has emerged as one of the most promising and high-potential solutions in the oil and gas industry. This method predicts flow patterns and water content based on the significant difference in dielectric constant between water and other fluids (crude oil, natural gas, etc.). While already in use in the oil and gas industry, numerous challenges remain. The primary technical bottleneck is the difficulty of accurately measuring high-salinity, full-range water content, and multiple flow patterns in two-phase flows. Summary of the Invention

[0004] The purpose of the present invention is to provide a new two-phase flow pattern and moisture content measurement device and method based on orthogonal complementary microwave dual-mode technology to address the problem of difficulty in accurately measuring the moisture content over the entire measuring range under complex flow states (variable flow patterns) of gas-water / oil-water two-phase flows and high salinity conditions.

[0005] The flow pattern and moisture content measurement device based on orthogonal microwave dual mode includes:

[0006] Test the combined pipe body, including non-metallic pipe sections and metallic pipe sections, for flowing gas-water / oil-water two-phase flow;

[0007] The dual-mode microwave sensor includes a conformal antenna array unit and an orthogonal microwave transmission line unit. The conformal antenna array unit is located in the front non-metallic pipe section, and the orthogonal microwave transmission line unit is located in the rear metallic pipe section. The orthogonal detection fields constructed within the conformal antenna array unit and the orthogonal microwave transmission line unit intersect to form an orthogonal and complementary dual-mode microwave detection field for omnidirectional coverage of the pipeline fluid area.

[0008] The data detection unit is used to generate a microwave signal and transmit the microwave signal to the excitation end of the dual-mode microwave sensor; at the same time, it receives the microwave signal transmitted back by the receiving end of the dual-mode microwave sensor, detects the amplitude and phase information thereof, and transmits the amplitude and phase information to the data processing unit.

[0009] A data processing unit, connected to the data detection unit, for processing measurement data; comprising:

[0010] a data receiving module, configured to receive the amplitude and phase information of the microwave signal transmitted by the data detection unit;

[0011] The data processing module is used to predict the flow pattern and water content by substituting the amplitude and phase information into the model.

[0012] The flow pattern and moisture content measurement method based on orthogonal microwave dual mode, using the above device, includes the following steps:

[0013] The dual-mode microwave sensor is installed in the two-phase flow pipeline through the test combined pipeline body;

[0014] A microwave signal is generated by a data detection unit and transmitted to an excitation end of a dual-mode microwave sensor;

[0015] The excitation end of the dual-mode microwave sensor propagates the microwave signal into the two-phase flow in the pipe;

[0016] The receiving end of the dual-mode microwave sensor receives the microwave signal after passing through the two-phase flow and transmits the microwave signal to the data detection unit;

[0017] The data detection unit detects the amplitude and phase information of the microwave signal and transmits the amplitude and phase information to the data processing unit;

[0018] The data processing unit substitutes the amplitude and phase information into the preset model to predict the flow pattern and water content of the two-phase flow.

[0019] The present invention adopts the above technical solution, and its beneficial effects are as follows:

[0020] The present invention combines two microwave modal methods, the antenna method and the transmission line method. Due to the different characteristics of the internal microwave detection field constructed by different principles, when the moisture content of the same flow pattern changes, the microwave signals of the two methods will show different change patterns. They have rich microwave phase / amplitude information and can improve the accuracy of moisture content measurement.

[0021] In addition, based on the core idea of ​​constructing an orthogonal microwave detection field, Qiaosi designed a combination structure of conformal antenna array units and orthogonal microwave transmission line units, which can realize a dual microwave orthogonal detection field staggered at 45 degrees. It can complement and fully cover the pipeline fluid area to capture the distribution of the gas-water / oil-water two-phase space and accurately invert the flow type information.

[0022] The present invention is suitable for application in the field of crude oil and natural gas engineering, and can achieve accurate online prediction of the flow pattern and water content of gas-water / oil-water two-phase flows. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the three-dimensional structure of the flow pattern and moisture content measurement device based on orthogonal microwave dual mode in an embodiment of the present application.

[0024] Figure 2 for Figure 1 Schematic diagram of the two-dimensional structure on the right.

[0025] Figure 3 The sensitive area of ​​the dual-modal sensor and the distribution of gas-water two-phase flow in the horizontal pipeline in the embodiment of the present application.

[0026] Figure 4 It is the data detection unit and data processing unit of the dual-modal sensor in the embodiment of the present application.

[0027] Figure 5 This is the relationship between the normalized amplitude / phase and moisture content of the dual-modal sensor under stratified flow in the embodiment of the present application.

[0028] Figure 6 This is the moisture content prediction result of the dual-modal sensor under stratified flow in the embodiment of this application.

[0029] Figure 7 It is the absolute error of the water content prediction of the dual-modal sensor under stratified flow in the embodiment of this application.

[0030] Figure 8 : This is the relationship between the normalized amplitude / phase and moisture content of the dual-mode sensor under annular flow in the embodiment of the present application.

[0031] Figure 9 This is the water content prediction result of the dual-mode sensor under annular flow in the embodiment of this application.

[0032] Figure 10 It is the absolute error of the water content prediction of the dual-mode sensor under annular flow in the embodiment of the present application.

[0033] Description of Figure Numbers:

[0034] 1. Non-metallic tube body of conformal antenna array unit; 2. Metallic tube body of orthogonal microwave transmission line unit; 3. Conformal antenna No. 1; 4. Conformal antenna No. 3; 5. Conformal antenna No. 2; 6. Conformal antenna No. 4; 7. Vertical transmission line; 8. Horizontal transmission line. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] like Figure 1 and Figure 2As shown, an embodiment of the present application provides a two-phase flow pattern and water content measurement device based on an orthogonal complementary microwave dual-mode sensor, which can be used for real-time measurement of key wellhead process parameters in the field of crude oil and natural gas engineering. The device includes: a non-metallic pipe body 1 of a conformal antenna array unit, through which the two-phase flow flows sequentially, and a metallic pipe body 2 of an orthogonal microwave transmission line unit, which together constitute the test assembly pipeline body; a dual-mode microwave sensor, including conformal antenna 1 3, conformal antenna 3 4, conformal antenna 2 5, and conformal antenna 4 6 of the conformal antenna array unit (mode 1); and vertical transmission lines 7 and horizontal transmission lines 8 of the orthogonal microwave transmission line unit (mode 2).

[0037] In some preferred embodiments, in the modal unit, four conformal antennas are affixed to the non-metallic pipe body 1 in axisymmetric, circumferentially spaced 90 degrees apart on the same cross-section. Opposite antennas are grouped in pairs: conformal antenna 1 3 and conformal antenna 2 5 form a vertical antenna pair, with the former's port serving as the excitation port (port 1) and the latter's port serving as the receiving port (port 2); and conformal antenna 3 4 and conformal antenna 4 6 form a horizontal antenna pair, with the former's port serving as the excitation port (port 3) and the latter's port serving as the receiving port (port 4). The sensitive areas of the two orthogonal antenna pairs form a non-invasive, orthogonal microwave detection field within the pipe. Figure 3 Figures (a), (b) and (c) respectively list and show the phase distribution of the orthogonal microwave field sensitive area of ​​the conformal antenna array and the low-water-content stratified flow, high-water-content stratified flow and annular flow. It can be seen that the distribution of gas and water phases is different under different flow patterns, and the situation of water medium with a larger dielectric constant entering the sensitive area is different, which can be judged that the microwave signal response will be different.

[0038] In some preferred embodiments, in the second mode unit, the metal inner electrodes of the vertical transmission line 7 and the horizontal transmission line 8 respectively penetrate the metal tube body 2 vertically and horizontally at certain intervals along the axial direction. Figure 2 The upper port of vertical transmission line 7 is the excitation port (port 5), and the lower port is the receiving port (port 6). The right port of vertical transmission line 8 is the excitation port (port 7), and the left port is the receiving port (port 8). The sensitive areas of the two orthogonal transmission lines form a set of intrusive orthogonal microwave detection fields inside the pipe. Figure 3 (d), (e) and (f) respectively show the phase distribution of the orthogonal microwave field sensitive area of ​​the orthogonal transmission line and the low water content stratified flow, high water content stratified flow and annular flow. Figure 3As shown in Figures (a), (b), and (c), the orthogonal detection fields within the internal structures of the first and second modal units intersect at 45 degrees, forming an orthogonal, complementary dual-modal microwave detection field that provides comprehensive coverage of the pipeline fluid area. Under the same flow pattern, although the gas-water phase distribution is identical, the water medium enters the sensitive areas of the two modalities differently. The dual, complementary, orthogonal microwave field can sense more information about the flow pattern distribution and more accurately predict the flow pattern. Similarly, when the moisture content changes, the regularity of the two-phase distribution changes, and the complementary orthogonal microwave field also responds easily, enabling more accurate prediction of moisture content changes.

[0039] Furthermore, the conformal antenna comprises a flexible dielectric substrate, a metal patch radiation unit, a metal ground unit, and a feed unit, and is a single-port structure. The transmission line comprises a metal rod inner conductor, a metal pipe outer conductor, and a coaxial connection feed unit, and is a dual-port structure.

[0040] In some preferred embodiments, the data detection unit and the data processing unit are as follows: Figure 4 As shown, microwave signals of multiple / single frequencies are generated by a microwave transmitting source, and eight identical microwave signals can be separated by an eight-way power divider. Four of the eight ways are respectively transmitted to the four excitation ports, namely port 1 of the vertical antenna pair, port 3 of the horizontal antenna pair, port 5 of the vertical transmission line 7, and port 7 of the horizontal transmission line. The other four ways are used as reference signals. Two radiation detectors respectively detect the amplitude difference between the received signal at port 2 of the vertical antenna pair and port 4 of the horizontal antenna pair and the reference signal, and output the vertical antenna pair amplitude voltage signal F AV and the horizontal antenna amplitude voltage signal F AH Similarly, the two phase detectors detect the phase difference between the received signal and the reference signal at the vertical transmission line port 6 and the horizontal transmission line port 8, and output the vertical transmission line phase voltage signal and horizontal transmission line phase voltage signals ;Amplitude / phase voltage signal F AV 、F AH 、 and They are collected by data acquisition cards and transmitted to the data processing unit.

[0041] The data processing unit receives the amplitude / phase voltage data, first performs normalization processing, and then performs real-time prediction based on the established flow pattern and water content model.

[0042] Let F AV 、F AH 、 and The normalized value F AV-nor 、F AH-nor 、 and The expressions are defined as follows

[0043]

[0044]

[0045]

[0046]

[0047] Where: F represents the amplitude; represents phase; subscript A represents conformal antenna; subscript E represents transmission line; subscript V represents vertical; subscript H represents horizontal; subscript -nor represents normalized result; subscript -max and subscript -min represent the maximum and minimum values ​​in the measurement, respectively.

[0048] The present application also provides a method for measuring the flow pattern and moisture content of a two-phase flow based on an orthogonal complementary microwave dual-mode sensor, using the above-mentioned device, including the following steps:

[0049] Install the above device in the gas-water / oil-water two-phase flow test pipeline through the flange;

[0050] The eight ports of the data detection unit are respectively connected to the excitation end and the receiving end of the vertical antenna pair and the excitation end and the receiving end of the horizontal antenna pair of the mode 1 unit of the dual-mode microwave sensor, and the excitation end and the receiving end of the vertical transmission line and the excitation end and the receiving end of the horizontal transmission line of the mode 2 unit;

[0051] Generate microwave signals of multiple / single frequencies through the data detection unit, and transmit the microwave signals to four excitation terminals of the dual-mode microwave sensor;

[0052] The excitation end of the dual-mode microwave sensor propagates the microwave signal into the gas-water / oil-water two-phase flow in the test pipe;

[0053] The receiving end of the dual-mode microwave sensor receives the microwave signal after being propagated to the two-phase flow, and transmits the microwave signal to the data detection unit;

[0054] The data detection unit receives the amplitude and phase information of the microwave signal;

[0055] The data processing unit substitutes the amplitude and phase information into a model to predict the flow pattern and water content.

[0056] Example: Since the flow pattern of gas-water two-phase flow is more complex than that of oil-water two-phase flow, and the two-phase flow of wellhead production generally has a higher salinity, the embodiment of this application takes gas-water two-phase flow and high conductivity 2 S / m (salinity of about 10,000 ppm) as an example to propose an implementation case.

[0057] Common gas-water two-phase flows include stratified flow, wavy flow, slug flow and annular flow. Considering that the flow patterns of the first three mainly present a stratified distribution structure with air in the upper layer and water in the lower layer on the cross-section of the measuring pipe, while the annular flow mainly presents an annular distribution structure with a central gas core and a peripheral liquid film ring, a two-phase flow flow pattern and water content measurement method based on orthogonal complementary microwave dual-modal sensor is proposed, with the two typical structures of stratified flow and annular flow as representatives.

[0058] 1. For stratified flow

[0059] Figure 5 The relationship between the normalized amplitude / phase and water content of the dual-mode sensor under stratified flow with a conductivity of 2 S / m is shown. It can be seen that the F of the mode-one conformal antenna array unit is AV-nor and F AH-nor With the two-mode orthogonal transmission line element and They all increase monotonically with the increase of moisture content, and can still well reflect the changes in moisture content in the pipeline under high conductivity.

[0060] In addition, it is found that the change trends of the normalized results of the two modal units are different. At the same water content, the amplitude F of the vertical and horizontal antenna pairs are AV-nor and F AH-nor are almost equal (the difference between the two is less than the first preset threshold), and the phase of the vertical and horizontal transmission lines and The difference is large (the difference between the two is greater than the second preset threshold). This is because the orthogonal detection characteristics of the two modes are different. Figure 3 Under stratified flow, the water medium enters the sensitive area of ​​vertical and horizontal antennas in the same way, so F AV-nor and F AH-nor are almost equal, however, the situations in the sensitive areas of vertical and horizontal transmission lines are different. When the water content is small ( Figure 3 In (d), the water medium only enters the sensitive area of ​​the vertical transmission line, but not the sensitive area of ​​the horizontal transmission line. The value is larger, Close to 0; when the moisture content is high ( Figure 3 In (e), the area of ​​water medium entering the sensitive area of ​​the vertical transmission line is smaller than that entering the horizontal transmission line, so Less than .

[0061] based on Figure 5 Medium FAV-nor 、F AH-nor 、 and Data, take the formula The constraint expression in is used to fit and establish a bimodal moisture content prediction model for stratified flow, with a correlation coefficient as high as 0.9986.

[0062]

[0063] Where: α represents the moisture content; the unknown coefficients a1, a2, a3, and a4 are 0.590096, 2.224807, 0.394659, and 0.028145, respectively.

[0064] Furthermore, in order to quantitatively evaluate the prediction performance of the moisture content model, the following evaluation indicators, namely absolute error Abs, relative error Rel, mean absolute error MAE, and mean absolute relative error MARE, are introduced:

[0065]

[0066]

[0067]

[0068]

[0069] Where: p represents the number of experiments; the subscripts pre and act of α represent the predicted value and true value of moisture content, respectively.

[0070] The prediction results and errors of the stratified flow water content are shown as follows: Figure 6 、 7 As shown in Table 1, for a water cut of 0 to 100% and a conductivity of 2 S / m, the predicted results have an Abs range of -4.62 to 2.08%, a Rel range of -2.66 to 1.30%, a MAE of 1.06%, and a MARE of 2.04%. This shows that the water cut prediction results are better under stratified flow.

[0071] 2. For annular flow

[0072] Figure 8 The relationship between the normalized amplitude / phase and water content of the dual-mode sensor under annular flow with a conductivity of 2 S / m is shown. AV-nor 、F AH-nor 、 and They also increase monotonically with the increase of water content, and can well reflect the change of water content in the pipeline under high conductivity. It is also found that the change trend of the normalized results of the two modal units is different, but at the same water content, the results of the two antenna pairs are the same, and the results of the two transmission lines are also the same. This is because the annular flow ( Figure 3 ) The gas and water phases are distributed symmetrically along the circumference. The water medium enters the sensitive area of ​​the vertical and horizontal antennas in the same way. Therefore, F AV-nor and F AH-nor are almost equal (the difference between the two is less than the first preset threshold); similarly, the situation of entering the sensitive area of ​​the vertical and horizontal transmission lines is the same, so and are almost equal (the difference between the two is less than the second preset threshold); however, since the microwave detection field characteristics of the two modal units are different, their normalized results are different.

[0073] based on Figure 8 Medium F AV-nor 、F AH-nor 、 and Data, take the formula The constraint expression in is used to fit and establish a bimodal water content prediction model for annular flow, with a correlation coefficient as high as 0.9999.

[0074]

[0075] In the formula, the unknown coefficients b1, b2, b3, and b4 are 1.289684, -0.154291, -0.289118, and -1.337603, respectively.

[0076] The prediction results and errors of annular flow moisture content are as follows: Figure 9 、 10 As shown in Table 1, for a water cut of 0 to 100% and a conductivity of 2 S / m, the predicted results have an Abs range of -0.12 to 0.06%, a Rel range of -0.12 to 0.09%, a MAE of 0.05%, and a MARE of 0.06%. This indicates that the dual-mode microwave sensor has higher accuracy in predicting water cut in annular flow than in stratified flow.

[0077] Table 1 Summary of moisture content prediction errors

[0078]

[0079] exist Figure 5 and Figure 8 In the two typical distribution structures of stratified flow and annular flow, the two amplitude signals (F AV-nor and F AH-nor ) and the two-phase signal of the mode two orthogonal transmission line unit ( and The two modal units can make corresponding regular responses according to the changes in the spatial distribution of the gas-water two-phase. Therefore, according to F AV-nor 、F AH-nor 、 and The flow pattern is predicted based on the difference in the time series changes of the signal, and the corresponding moisture content prediction model is selected according to the flow pattern, thereby realizing accurate online measurement of the two-phase flow pattern and moisture content based on the orthogonal complementary microwave dual-modal sensor.

[0080] In summary, the embodiment of the present application constructs a dual-complementary orthogonal microwave detection field by integrating the conformal antenna array unit (mode one) and the orthogonal microwave transmission line unit (mode two) to complement each other and cover the two-phase flow area in the pipeline. Based on the amplitude / phase signal changes of the dual-mode microwave, the measurement of the dual parameters of flow type and full-range water content is achieved.

[0081] The above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it may also include many other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A flow pattern and moisture content measurement device based on orthogonal microwave dual modes, characterized by: include: Test the combined pipe body, including non-metallic pipe sections and metallic pipe sections, for flowing gas-water / oil-water two-phase flow; A dual-mode microwave sensor includes a conformal antenna array unit and an orthogonal microwave transmission line unit, wherein the conformal antenna array unit is located in the front non-metallic tube section and the orthogonal microwave transmission line unit is located in the rear metal tube section; The conformal antenna array unit includes four conformal antennas, which are axially symmetrically installed on the non-metallic pipe section at 90-degree intervals on the same cross section. Opposite antennas are grouped in pairs to form a vertical antenna pair and a horizontal antenna pair, respectively, thereby constructing a set of non-intrusive orthogonal microwave detection fields; The orthogonal microwave transmission line unit includes two transmission lines, wherein the metal inner conductors of the two transmission lines respectively penetrate the metal pipe section vertically and horizontally at a certain interval along the axial direction, forming a vertical transmission line and a horizontal transmission line respectively, thereby constructing a set of intrusive orthogonal microwave detection fields; The orthogonal detection fields of the conformal antenna array unit and the orthogonal microwave transmission line unit are staggered at 45 degrees to form an orthogonal complementary dual-mode microwave detection field for omnidirectional coverage of the pipeline fluid area; a data detection unit, configured to generate a microwave signal and transmit the microwave signal to the excitation end of the dual-mode microwave sensor; simultaneously receive the microwave signal transmitted back by the receiving end of the dual-mode microwave sensor, detect the amplitude and phase information thereof, and transmit the amplitude and phase information to the data processing unit; A data processing unit, connected to the data detection unit, for processing measurement data; comprising: a data receiving module, configured to receive the amplitude and phase information of the microwave signal transmitted by the data detection unit; The data processing module is used to predict the flow pattern and water content by substituting the amplitude and phase information into the model.

2. The flow pattern and moisture content measurement device based on orthogonal microwave dual mode according to claim 1 is characterized in that: include: The data detection unit includes: A microwave transmitting source for generating microwave signals of multiple or single frequencies; An eight-power splitter, used to split the microwave signal into eight identical signals; Two amplitude detectors, used to detect the amplitude difference between the vertical antenna pair and the horizontal antenna pair respectively; Two phase detectors, used to detect the phase difference of the vertical transmission line and the horizontal transmission line respectively; An acquisition card is used to acquire amplitude and phase voltage signals and transmit them to the data processing unit.

3. The flow pattern and moisture content measuring device based on orthogonal microwave dual mode according to claim 1 or 2, characterized in that: The data processing unit further includes: A data normalization module is used to normalize the collected amplitude and phase voltage signals; The model fitting module is used to fit the prediction model of flow pattern and water content based on the normalized data.

4. A method for measuring flow pattern and moisture content based on orthogonal microwave dual modes, using the device of claim 3, characterized in that: The dual-mode microwave sensor is installed in the two-phase flow pipeline through the test combined pipeline body; A microwave signal is generated by a data detection unit and transmitted to an excitation end of a dual-mode microwave sensor; The excitation end of the dual-mode microwave sensor propagates the microwave signal into the two-phase flow in the pipe; The receiving end of the dual-mode microwave sensor receives the microwave signal after passing through the two-phase flow and transmits the microwave signal to the data detection unit; The data detection unit detects the amplitude and phase information of the microwave signal and transmits the amplitude and phase information to the data processing unit; The data processing unit substitutes the amplitude and phase information into the preset model to predict the flow pattern and water content of the two-phase flow.

5. The flow pattern and moisture content measurement method based on orthogonal microwave dual mode according to claim 4 is characterized in that: The flow pattern is identified as follows: Calculating a difference value between the normalized amplitude signal and the phase signal includes: Amplitude difference ΔFA = | - |; among them is the vertical antenna amplitude voltage signal F AV The normalized amplitude signal, is the amplitude voltage signal F of the horizontal antenna AH Normalized amplitude signal; Phase difference value ΔφE = | - |; among them is the vertical transmission line phase voltage signal The normalized phase signal, is the horizontal transmission line phase voltage signal Normalized phase signal; Set a threshold based on the difference value to determine the flow type: If ΔFA is less than a first preset threshold and ΔφE is greater than a second preset threshold, it is identified as stratified flow; If ΔFA is smaller than a first preset threshold and ΔφE is smaller than a second preset threshold, it is identified as annular flow.

6. The flow pattern and moisture content measurement method based on orthogonal microwave dual mode according to claim 5 is characterized in that: When the flow is stratified, the water content prediction model is expressed as: Among them, α represents the moisture content, 、 、 、 are model coefficients obtained through fitting.

7. The flow pattern and moisture content measurement method based on orthogonal microwave dual mode according to claim 5 is characterized in that: When it is annular flow, the expression of its water content prediction model is: Among them, α represents the moisture content, 、 、 、 are model coefficients obtained through fitting.

8. The flow pattern and moisture content measurement method based on orthogonal microwave dual mode according to claim 6 or 7, characterized in that: The water content prediction model can perform full-range measurement under the condition of 2S / m conductivity.

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