Conductive probe structure and method for detecting gas phase parameters of gas-liquid-solid three-phase flow

Abstract

The invention discloses a conducting probe structure and method for detecting gas phase parameters of gas-liquid-solid three-phase flow. The conducting probe structure comprises a hollow probe head and a probe, the probe comprises an upstream probe and a downstream probe; the hollow needle head is provided with an opening at a set distance above the needle head; the upstream probe and the downstream probe are arranged in the hollow probe head; the upstream probe is in contact with the external environment through the opening; the downstream probe is in contact with the external environment through the needle head of the hollow needle head. And an insulating layer is filled among the hollow probe head, the upstream probe and the downstream probe. The hollow needle head is made of stainless steel and serves as an exciting electrode; the upstream probe and the downstream probe are silver core insulated wires and are respectively used as a first detection electrode and a second detection electrode. The excitation electrode and the two detection electrodes are integrated on a single needle, so that two-point measurement can be met by only one needle. The compact structure not only enables the probe to maintain a small size, but also reduces the distance between the excitation electrode and the detection electrode, and can reduce the sensitive range of the detection electrode.

Description

Technical Field

[0001] The present invention relates to the technical field of gas phase parameter detection, and particularly to a conductance probe structure and method for detecting gas phase parameters of gas-liquid-solid three-phase flow. Background Art

[0002] Gas-liquid-solid three-phase flow is an important research object in the process of oil and gas exploitation. Detecting its process parameters is of great significance for both production and scientific research. Gas phase parameters play an important role in describing three-phase flow behavior, characterization, efficiency, etc. Detecting gas phase parameters not only has important value for studying three-phase flow laws, but also provides a practical basis for verifying Computational Fluid Dynamics models. The conductance probe technology, based on the difference in conductivity between the gas phase and the liquid phase, can quickly distinguish bubbles passing through the probe and reflect various gas phase parameters, so it is widely used to detect gas phase parameters of multiphase flow. Since solids will not pass through the probe and do not affect the measurement of bubbles by the probe, the conductance probe can be applied to gas phase detection of gas-liquid-solid three-phase flow.

[0003] Currently, traditional three-phase flow detection uses multi-head conductance probes, which are usually composed of a metal shell and a combination of multiple needles. In order to reduce the interference of the probe itself on the flow field, the probe is generally wrapped with an insulating layer and has a structure where the shell is far from the needle tip. However, in gas-liquid-solid three-phase flow, due to the lack of protection of the needle tip, the needle tip is easily damaged during long-term use. In addition, this structure expands the sensitive range of the needle tip, limits the size of the probe and thus brings more measurement errors.

[0004] Therefore, how to invent a conductance probe structure and detection method to overcome the shortcomings of the original probe and improve the limitations of the double-head or multi-head probe structure has become an urgent problem to be solved. Summary of the Invention

[0005] To this end, the present invention provides a conductance probe structure and method for detecting gas phase parameters of gas-liquid-solid three-phase flow, integrating the excitation electrode and two detection electrodes on a single needle, so only one needle is needed to meet two-point measurement. The compact structure not only keeps the probe at a small size, but also reduces the distance between the excitation electrode and the detection electrode, which can reduce the sensitive range of the detection electrode.

[0006] To achieve the above object, the present invention provides the following technical solution: A conductance probe structure for detecting gas phase parameters of gas-liquid-solid three-phase flow, comprising a hollow needle tip and a probe; the probe includes an upstream probe and a downstream probe; the hollow needle tip is provided with an opening at a set distance above the needle tip; The upstream probe and the downstream probe are arranged inside the hollow needle tip; the upstream probe is in contact with the external environment through the opening; the downstream probe is in contact with the external environment through the needle tip of the hollow needle tip.

[0007] As a preferred solution for the conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow, an insulating layer is filled between the hollow needle, the upstream probe and the downstream probe; The hollow needle is made of stainless steel and serves as the excitation electrode; Both the upstream probe and the downstream probe are silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively.

[0008] As a preferred solution for the conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow, the insulating layer is epoxy resin. The insulating layer completely wraps the non-exposed parts of the upstream probe and the downstream probe, and after curing, the insulating layer fits against the inner wall of the hollow needle.

[0009] The present invention also provides a method for detecting gas-phase parameters of gas-liquid-solid three-phase flow using a conductance probe, including: Insert the conductance probe into a set position in the target flow pattern; Apply corresponding voltages to the detection electrode and the excitation electrode of the conductance probe; Detect the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode to obtain the target gas-phase parameters.

[0010] As a preferred solution for the method for detecting gas-phase parameters of gas-liquid-solid three-phase flow using a conductance probe, the conductance probe includes a hollow needle, an upstream probe and a downstream probe; The hollow needle has an opening at a set distance above the needle tip; the upstream probe contacts the target flow pattern through the opening; the downstream probe contacts the target flow pattern through the needle tip of the hollow needle.

[0011] As a preferred solution for the method for detecting gas-phase parameters of gas-liquid-solid three-phase flow using a conductance probe, the hollow needle is filled with an insulating layer, and the upstream probe and the downstream probe are wrapped in the insulating layer, and the target flow pattern cannot enter the hollow needle.

[0012] As a preferred solution for the method for detecting gas-phase parameters of gas-liquid-solid three-phase flow using a conductance probe, the hollow needle is made of stainless steel and serves as the excitation electrode; both the upstream probe and the downstream probe are silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively.

[0013] As a preferred solution of the conductance probe detection method for detecting the gas-phase parameters of gas-liquid-solid three-phase flow, during the process of detecting the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode, the upstream probe transmits the upstream signal, and the downstream probe transmits the downstream signal; the performance of the conductance probe is evaluated through the relative error between the void fraction of the upstream signal and the void fraction of the downstream signal; the calculation formula for the relative error is:

[0014] In the formula, is the relative error; and are the void fractions of the upstream signal and the downstream signal respectively; The gas-phase parameters include bubble velocity, void fraction, and bubble size distribution.

[0015] As a preferred solution of the conductance probe detection method for detecting the gas-phase parameters of gas-liquid-solid three-phase flow, by calculating the correlation degree between the upstream signal and the downstream signal, the correlation coefficient is obtained; whether the bubble can pass through the probe normally is judged through the correlation coefficient, and the higher the correlation coefficient, the easier the bubble can pass through the probe normally; The calculation formula for the correlation coefficient is:

[0016] In the formula, R xy is the correlation coefficient; x(t) and y(t) are the upstream signal and the downstream signal at time t respectively, τ is the transit time, and T is the integration time.

[0017] As a preferred solution of the conductance probe detection method for detecting the gas-phase parameters of gas-liquid-solid three-phase flow, when the correlation coefficient R xy is greater than the set threshold, it is determined that the bubble passes through the probe normally; the range of the set threshold is 0.7 - 0.9; The application of the conductance probe in the gas-liquid vertical upward pipe includes the measurement of bubbly flow, slug flow, and churn flow; The sensitive range of the probe is verified through electric field simulation, and the sensitive range is defined as the area where the change rate of the electric field intensity around the detection electrode is greater than 10%.

[0018] The present invention has the following advantages: The present invention includes a hollow needle and a probe; the probe includes an upstream probe and a downstream probe; the hollow needle is provided with an opening at a set distance above the needle tip; the upstream probe and the downstream probe are arranged inside the hollow needle; the upstream probe is in contact with the external environment through the opening; the downstream probe is in contact with the external environment through the needle tip of the hollow needle. An insulating layer is filled between the hollow needle, the upstream probe and the downstream probe; the hollow needle is made of stainless steel and serves as an excitation electrode; both the upstream probe and the downstream probe are silver-core insulated wires and serve as a first detection electrode and a second detection electrode respectively. The insulating layer is epoxy resin, and the insulating layer completely wraps the non-exposed parts of the upstream probe and the downstream probe, and after curing, the insulating layer fits against the inner wall of the hollow needle. The present invention inserts the conductivity probe into a set position in the target flow pattern; applies corresponding voltages to the detection electrode and the excitation electrode of the conductivity probe; and detects the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode to obtain the target gas-phase parameters. The present invention integrates the excitation electrode and two detection electrodes on a single stainless steel needle, and has the detection function of a double-headed conductivity probe. Since the detection electrodes are protected by the steel needle, the probe will not be damaged by particle impact. The integrated structure not only gives the probe a size advantage, but also shortens the distance between the excitation electrode and the detection electrode. Electric field analysis shows that this structure can effectively control the sensitive range of the detection electrode. The new probe has obvious advantages. Therefore, the new probe structure can not only improve the quality of the measurement signal, but is also more suitable for measuring small-sized bubbles. In addition, the new probe can continue to increase the number of detection electrodes without increasing the probe size, and this advantage allows for further development of more measurement functions for this probe in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below are only exemplary, and for those of ordinary skill in the art, other implementation drawings can be obtained by extension based on the provided drawings without creative efforts.

[0020] The structures, ratios, sizes, etc. shown in this specification are only used to cooperate with the content disclosed in the specification for those who are familiar with this technology to understand and read, and are not used to limit the limited conditions under which the present invention can be implemented. Therefore, they do not have a substantial technical meaning. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention.

[0021] Figure 1Schematic diagram of a conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow provided in Embodiment 1 of the present invention; Figure 2 Schematic diagram of the flow chart of a detection method of a conductance probe for detecting gas-phase parameters of gas-liquid-solid three-phase flow provided in Embodiment 2 of the present invention; Figure 3 Schematic diagram of the circuit principle of a conductance probe for gas-phase parameters of gas-liquid-solid three-phase flow in a detection method of a conductance probe for detecting gas-phase parameters of gas-liquid-solid three-phase flow provided in Embodiment 2 of the present invention; Figure 4 Schematic diagram of the comparison between a typical double-head probe and the electric field simulation of the present invention in a detection method of a conductance probe for detecting gas-phase parameters of gas-liquid-solid three-phase flow provided in Embodiment 2 of the present invention; wherein, a is the electric field simulation of the typical double-head probe; b is the electric field simulation of the probe of the present invention; Figure 5 Schematic diagram of a conductance probe and a gas-liquid vertical upward flow device in a possible embodiment provided in Embodiment 2 of the present invention; wherein, a is the probe of the present invention; b is the traditional double-head probe; c is the gas-liquid vertical upward flow device; Figure 6 Schematic diagram of different flow patterns in a possible embodiment provided in Embodiment 2 of the present invention; Figure 7 In the present invention provided in a possible embodiment in Embodiment 2 of the present invention and the traditional double-head probe RE Comparison schematic diagram; Figure 8 In the present invention provided in a possible embodiment in Embodiment 2 of the present invention and the traditional double-head probe R xy Comparison schematic diagram; Figure 1 Among them, 1. Hollow needle head; 2. Upstream probe; 3. Downstream probe; 4. Opening; 5. Insulating layer. Specific implementation manners

[0022] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. 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. Embodiment

[0023] See Figure 1, Embodiment 1 of the present invention provides a conductance probe structure for detecting gas-phase parameters of a gas-liquid-solid three-phase flow, including a hollow needle 1 and a probe; the probe includes an upstream probe 2 and a downstream probe 3; the hollow needle 1 is provided with an opening 4 at a set distance above the needle tip; The upstream probe 2 and the downstream probe 3 are arranged inside the hollow needle 1; the upstream probe 2 is in contact with the external environment through the opening 4; the downstream probe 3 is in contact with the external environment through the needle tip of the hollow needle 1.

[0024] In this embodiment, an insulating layer 5 is filled between the hollow needle 1, the upstream probe 2 and the downstream probe 3. The hollow needle 1 is made of stainless steel and serves as an excitation electrode; the upstream probe 2 and the downstream probe 3 are both silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively.

[0025] Specifically, the inside of the hollow needle 1 is filled with the insulating layer 5 to ensure that liquid cannot enter the inside of the hollow needle 1; the downstream probe 3 can only be in contact with the external liquid through the opening, avoiding contact between the liquid and the downstream probe 3 from the inside of the hollow needle 1.

[0026] In this embodiment, the insulating layer 5 is epoxy resin, and the insulating layer 5 completely wraps the non-exposed parts of the upstream probe 2 and the downstream probe 3, and the insulating layer 5 fits against the inner wall of the hollow needle 1 after curing.

[0027] In summary, the present invention includes a hollow needle and a probe; the probe includes an upstream probe and a downstream probe; the hollow needle is provided with an opening at a set distance above the needle tip; the upstream probe and the downstream probe are arranged inside the hollow needle; the upstream probe is in contact with the external environment through the opening; the downstream probe is in contact with the external environment through the needle tip of the hollow needle. An insulating layer is filled between the hollow needle, the upstream probe and the downstream probe; the hollow needle is made of stainless steel and serves as an excitation electrode; both the upstream probe and the downstream probe are silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively. The insulating layer is epoxy resin, and the insulating layer completely wraps the non-exposed parts of the upstream probe and the downstream probe, and after curing, the insulating layer fits the inner wall of the hollow needle. The present invention integrates the excitation electrode and two detection electrodes on a single stainless steel needle, and has the detection function of a double-headed conductivity probe. Since the detection electrodes are protected by the steel needle, the probe will not be damaged by particle impact. The integrated structure not only gives the probe a size advantage, but also shortens the distance between the excitation electrode and the detection electrodes. Electric field analysis shows that this structure can effectively control the sensitive range of the detection electrodes, and the present invention has obvious advantages. Therefore, the present invention can not only improve the quality of the measurement signal, but is also more suitable for measuring small-sized bubbles. In addition, the present invention can continue to increase the number of detection electrodes without increasing the size of the probe, and this advantage allows for further development of more measurement functions for this probe in the future. Embodiment

[0028] See Figure 2 and Figure 3 , Embodiment 2 of the present invention also provides a conductivity probe detection method for detecting the gas-phase parameters of a gas-liquid-solid three-phase flow, including: S1. Insert the conductivity probe into a set position in the target flow pattern; S2. Apply corresponding voltages to the detection electrode and the excitation electrode of the conductivity probe; S3. Detect the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode to obtain the target gas-phase parameters.

[0029] In this embodiment, in step S1, the conductivity probe is inserted into a set position in the target flow pattern; wherein, the conductivity probe includes a hollow needle, an upstream probe and a downstream probe; the hollow needle is provided with an opening at a set distance above the needle tip; the upstream probe is in contact with the target flow pattern through the opening; the downstream probe is in contact with the target flow pattern through the needle tip of the hollow needle.

[0030] In this embodiment, the hollow needle is filled with an insulating layer, and the upstream probe and the downstream probe are wrapped in the insulating layer, and the target flow pattern cannot enter the hollow needle.

[0031] The hollow needle is made of stainless steel and serves as an excitation electrode; both the upstream probe and the downstream probe are silver-core insulated wires and serve as detection electrodes.

[0032] Specifically, the conductance probe consists of a single hollow stainless-steel needle and two specially made silver-core insulated wires. An opening is provided on the side of the needle. The insulated wires are hidden inside the needle, and the wire cores are exposed at the tip and the side opening of the needle. Epoxy resin is used to fix the insulated wires and prevent liquid from entering the needle. The entire needle serves as the excitation electrode, and the exposed wire cores serve as detection electrodes to measure the electrical connection between the needle and the wire cores. Among them, the wire core exposed at the tip serves as the upstream electrode, and the wire core exposed at the side opening serves as the downstream electrode. Since the insulated wires are wrapped by the stainless-steel needle and no additional insulating coating is required on the surface of the needle, this probe can resist the impact of solid particles and there is no need to worry about the problem of insulation performance failure.

[0033] In this embodiment, in step S2, corresponding voltages are applied to the detection electrode and the excitation electrode of the conductance probe; Specifically, the hollow needle is made of stainless steel and serves as the excitation electrode; the upstream probe and the downstream probe are both silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively; after the power is turned on, corresponding voltages are applied to the detection electrode and the excitation electrode of the conductance probe to detect the target flow pattern.

[0034] In this embodiment, the differences between the present invention and traditional probes are analyzed through the electric field: The sensitive range of the probe is verified through electric field simulation, and the sensitive range is defined as the area where the change rate of the electric field intensity around the detection electrode is greater than 10%. The distance between the metal shell and the tip of the traditional probe is relatively far, which will expand the detection range of the tip. When a bubble passes near the probe but does not cross the tip, the signal of the detection electrode will also fluctuate due to the change of the medium, which is likely to cause misidentification of the medium. In the COMSOL Multiphysics environment, the electric field distribution of a typical probe structure and the new probe structure in water is simulated.

[0035] The general structure of a typical double-head conductance probe is as Figure 4 shown in a. Except for the tip, the probe is covered with an insulating layer and sheathed with a stainless-steel shell, and the distance between the shell and the tip is relatively far. The voltage is directly applied to the shell, and the tip is connected to a load resistor. The electric potential decreases uniformly from the shell to the tip direction, and the electric field intensity is very large near the entire probe, which means that once a bubble passes near the probe, it will have a strong impact on the electric field.

[0036] The structure of the present invention is as Figure 4 shown in b. The detection electrode is integrated on the needle tip, and the needle tip serves as the excitation electrode. The detection electrode and the excitation electrode are separated by only an insulating layer. The detection electrode is also connected to a load resistor and its voltage level is controlled to be the same as Figure 4 that of the tip of the probe in a. The electric potential does not change significantly in the entire space except near the detection electrode, and only decreases suddenly near the detection electrode. The electric field strength is also only very large near the detection electrode. By comparing the electric potential distributions of the two, it can be seen that even at the same electric potential level, Figure 4 the electric field lines in b are closer to the detection electrode. This means that even if a bubble exists around the detection electrode, its influence on the electric field is small. Only when the bubble wraps the detection electrode will the electric field change significantly. This also shows that the present invention can break away from the limitations of the traditional probe structure, effectively control the sensitive range of the detection electrode, and can achieve precise measurement of bubble information.

[0037] In this embodiment, in step S3, the gas phase parameters in the target flow pattern are detected through the detection electrode and the excitation electrode to obtain the target gas phase parameters.

[0038] Specifically, the upstream probe transmits the upstream signal, and the downstream probe transmits the downstream signal; the upstream signal and the downstream signal are collected by a signal acquisition system and analyzed to obtain the target gas phase parameters. The gas phase parameters include bubble velocity, void fraction, and bubble size distribution.

[0039] In this embodiment, the performance of the conductance probe is evaluated by the relative error between the void fraction of the upstream signal and the void fraction of the downstream signal; the calculation formula for the relative error is:

[0040] In the formula, is the relative error; and are the void fraction of the upstream signal and the void fraction of the downstream signal respectively.

[0041] In this embodiment, the correlation coefficient is obtained by calculating the correlation degree between the upstream signal and the downstream signal; the bubble's normal crossing of the probe is judged by the correlation coefficient. The higher the correlation coefficient, the easier it is for the bubble to normally cross the probe; The calculation formula for the correlation coefficient is:

[0042] In the formula, R xyis the correlation coefficient; x(t) and y(t) are the upstream signal and downstream signal at time t respectively, τ is the transit time, and T is the integration time. When the correlation coefficient R xy is greater than the set threshold, it is determined that the bubble passes through the probe normally; the range of the set threshold is 0.7 - 0.9; In a possible embodiment, an experimental verification example of the present invention and a traditional probe is provided as follows: The present invention is fixed at the center of the pipeline through a bracket, and the cable connected to the electrode passes through the bracket and extends out of the pipeline, as Figure 5 shown in a. A traditional double - headed probe will also be used in the experiment to provide reference data, as Figure 5 shown in b. The probe will be placed in a vertical upward gas - liquid pipe, and various gas - liquid two - phase flow patterns can be generated by controlling the gas - liquid inlet flow rate, as Figure 5 shown in c. According to the working conditions required by the experiment, three flow patterns of bubbly flow, slug flow, and churn flow are generated respectively, as Figure 6 shown. The experiment is carried out under the three flow patterns of bubbly flow, slug flow, and churn flow. The new probe and the double - headed probe measure the data at the same position and working conditions for 30 s in turn.

[0043] In different flow patterns, the void fraction of the upstream and downstream signals of the two RE is compared as Figure 7 shown. In these three flow patterns, the RE of the present invention is lower. Especially in bubbly flow, since the bubbles are generally small, the traditional probe has a stronger interfacial interference on small bubbles, and the bubbles are prone to deformation, resulting in a large difference in the measured gas - phase void fraction between the upstream and downstream. And due to the small overall size of the new probe, the influence on bubble deformation is lower, so the void fraction RE is also lower. The maximum of the upstream and downstream signals of the two R xy is compared as Figure 8 shown. The correlation degree of the upstream and downstream signals of the present invention is higher, indicating that the bubbles are less affected by the probe size and the distance between the upstream and downstream electrodes, and the probability that the bubbles can pass through the probe normally is higher. While due to the structural limitation, the traditional probe is more likely to have the phenomenon of bubble leakage in the measurement of bubbly flow, and its correlation degree of the upstream and downstream signals is also the lowest among the three flow patterns.

[0044] In summary, the present invention inserts a conductivity probe into a set position in a target flow pattern; applies corresponding voltages to the detection electrode and the excitation electrode of the conductivity probe; and detects the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode to obtain the target gas-phase parameters. The present invention integrates the excitation electrode and two detection electrodes on a single stainless-steel needle, having the detection function of a double-headed conductivity probe. Since the detection electrode is protected by the steel needle, the probe will not be damaged by particle impact. The integrated structure not only gives the probe a size advantage but also shortens the distance between the excitation electrode and the detection electrode. Electric field analysis shows that this structure can effectively control the sensitive range of the detection electrode, and the present invention has obvious advantages. Therefore, the present invention can not only improve the quality of the measurement signal but is also more suitable for measuring small-sized bubbles. In addition, the present invention can continue to increase the number of detection electrodes without increasing the size of the probe, and this advantage allows for further development of more measurement functions for this probe in the future.

[0045] In the foregoing, the present invention has been described in a relatively specific and detailed manner through general descriptions and specific embodiments. It should be understood that based on the technical concept of the present invention, several conventional adjustments or further innovations can be made to these specific embodiments; but as long as they do not depart from the technical concept of the present invention, the technical solutions obtained through these conventional adjustments or further innovations also fall within the scope of protection of the claims of the present invention.

Claims

1. A conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow, characterized in that, It includes a hollow needle (1) and a probe; the probe includes an upstream probe (2) and a downstream probe (3); the hollow needle (1) is provided with an opening (4) at a set distance above the needle tip; The upstream probe (2) and the downstream probe (3) are arranged inside the hollow needle (1); the upstream probe (2) is in contact with the external environment through the opening (4); the downstream probe (3) is in contact with the external environment through the needle tip of the hollow needle (1).

2. The conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 1, characterized in that, An insulating layer (5) is filled between the hollow needle (1), the upstream probe (2) and the downstream probe (3); The hollow needle (1) is made of stainless steel and serves as an excitation electrode; Both the upstream probe (2) and the downstream probe (3) are silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively.

3. The conductance probe structure for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 2, characterized in that The insulating layer (5) is epoxy resin. The insulating layer (5) completely wraps the non-exposed parts of the upstream probe (2) and the downstream probe (3), and after curing, the insulating layer (5) fits the inner wall of the hollow needle (1).

4. A conductance probe detection method for detecting gas-phase parameters of gas-liquid-solid three-phase flow, characterized in that, It includes: Insert the conductivity probe into a set position in the target flow pattern; Apply corresponding voltages to the detection electrode and the excitation electrode of the conductivity probe; Detect the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode to obtain the target gas-phase parameters.

5. The conductance probe detection method for detecting the gas-phase parameters of a gas-liquid-solid three-phase flow according to claim 4, characterized in that, The conductivity probe includes a hollow needle, an upstream probe and a downstream probe; The hollow needle is provided with an opening at a set distance above the needle tip; the upstream probe is in contact with the target flow pattern through the opening; the downstream probe is in contact with the target flow pattern through the needle tip of the hollow needle.

6. A conductance probe detection method for detecting gas phase parameters of gas-liquid-solid three-phase flow according to claim 5, characterized in that, The hollow needle is filled with an insulating layer, and the upstream probe and the downstream probe are wrapped in the insulating layer, and the target flow pattern cannot enter the hollow needle.

7. The conductance probe detection method for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 6, characterized in that, The hollow needle is made of stainless steel and serves as an excitation electrode; both the upstream probe and the downstream probe are silver-core insulated wires and serve as the first detection electrode and the second detection electrode respectively.

8. A conductance probe detection method for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 7, characterized in that, During the process of detecting the gas-phase parameters in the target flow pattern through the detection electrode and the excitation electrode, the upstream probe transmits an upstream signal and the downstream probe transmits a downstream signal; Evaluate the performance of the conductivity probe through the relative error between the void fraction of the upstream signal and the void fraction of the downstream signal; the calculation formula of the relative error is:

9. In the formula, is the relative error; and are the upstream signal void fraction and the downstream signal void fraction respectively; The gas-phase parameters include bubble velocity, void fraction and bubble size distribution.

10. A conductance probe detection method for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 8, characterized in that, Calculate the correlation degree between the upstream signal and the downstream signal to obtain the correlation coefficient; judge whether the bubble passes through the probe normally through the correlation coefficient; The calculation formula of the correlation coefficient is:

11. Wherein, R xy is the correlation coefficient; x(t) and y(t) are the upstream signal and downstream signal at time t respectively, τ is the transit time, and T is the integration time.

12. A conductance probe detection method for detecting gas-phase parameters of gas-liquid-solid three-phase flow according to claim 9, characterized in that, When the correlation coefficient R xy is greater than the set threshold, it is determined that the bubble normally passes through the probe; the range of the set threshold is 0.7 - 0.9; The application of the conductivity probe in a vertical gas-liquid upward pipe includes the measurement of bubbly flow, slug flow and churn flow; Verify the sensitive range of the probe through electric field simulation, and the sensitive range is defined as the area where the change rate of the electric field intensity around the detection electrode is greater than 10%.

Images