Liquid film thickness static calibration device and method

Abstract

The invention relates to the technical field of gas-water two-phase flow research, in particular to a liquid film thickness static calibration device and method.A calibration experiment device is arranged by combining a point-to-probe assembly and a liquid film thickness measuring mechanism, when liquid is in a non-flow state, the liquid film thickness can be measured, meanwhile, an output voltage value can be obtained, and the measurement accuracy is improved. The mathematical relationship between the liquid film thickness and the voltage value output by the acquisition device is successfully established, and a foundation is laid for accurately measuring the liquid film thickness in the pipe in practical application. The device has the advantages of being simple in structure and easy to assemble. The calibration method is simple and short in step, simple in operation process and easy to implement, and when the actual liquid film thickness is measured after calibration in the mode, the influence of liquid film flow on a measurement result is greatly reduced, so that the measurement result is more accurate. In the prior art, a conducting probe measuring method has the problems of large error and low reliability in measuring the thickness of a liquid film.

Description

Technical Field

[0001] The invention relates to the field of gas-water two-phase flow research, and specifically relates to a static calibration device and method for liquid film thickness, in particular to a static calibration device and method for measuring liquid film thickness with a conductivity probe. Background Art

[0002] The problem of measuring the thickness of the gas-liquid two-phase flow film has long existed in the oil and gas well production process. The liquid film is one of the important parameters in the oil and gas well production process, which directly affects the downhole production and production efficiency. Accurately measuring the thickness of the liquid film can help engineers understand the situation at the bottom of the well, help to judge the production and liquid production of the oil and gas well, and improve the production efficiency of the oil well.

[0003] Based on different physical principles, there are different methods for measuring the thickness of gas-liquid two-phase flow film, such as conductivity probe measurement method, optical method and nuclear radiation method. The optical method is difficult to be directly applied to real-time measurement on the oil well site due to the complex and harsh downhole measurement environment. The nuclear radiation method has serious safety protection issues due to the use of radioactive materials. The conductivity probe measurement method is widely used in liquid film measurement due to its faster response speed, more stable performance and easy implementation.

[0004] However, due to the strong turbulent kinetic energy of the gas-water mixed fluid and the uneven distribution of the liquid film along the circumference in the tube, the traditional conductivity probe measurement method has large errors. Summary of the invention

[0005] In view of the problem that the conductivity probe measurement method in the prior art has large error and low reliability in measuring liquid film thickness, the present invention provides a liquid film thickness static calibration device and method.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a static calibration device for liquid film thickness, comprising a dish, a cover plate is arranged on the top of the dish, a liquid film thickness measuring mechanism is inserted on the cover plate; a drain port is arranged at the bottom of the dish; a conductivity probe assembly is inserted at the bottom of the dish; The conductivity probe assembly includes two parallel probe electrodes, and the probe electrodes are connected to a constant current source for providing a constant current to the conductivity probe assembly; The probe electrode and the liquid film thickness measuring mechanism are both connected to a data acquisition device for collecting the voltage at both ends of the probe electrode and the measured value of the liquid film thickness measuring mechanism; The data acquisition device is connected to a data analysis device for calculating the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode according to the voltage at both ends of the probe electrode and the measured value of the liquid film thickness measurement mechanism.

[0007] Furthermore, a threaded hole is arranged on the top of the wall of the dish; and a positioning hole is arranged on the cover plate at a position corresponding to the threaded hole.

[0008] Furthermore, the conductivity probe assembly also includes a probe base, which is detachably connected to the bottom of the dish; a shell is arranged outside the probe electrode, and the shell is fixedly connected to the probe base.

[0009] Furthermore, the probe electrode sleeve is provided with a heat shrink tube, and the heat shrink tube and the shell are fixed and sealed by structural adhesive.

[0010] Furthermore, the cover plate is provided with an insertion hole for inserting a fixed liquid film thickness measuring mechanism.

[0011] Furthermore, the liquid film thickness measuring mechanism is a micrometer.

[0012] Furthermore, when the micrometer is fixed, the limit distance of the micrometer head is greater than or equal to the distance from the tail of the micrometer head to the bottom of the dish.

[0013] Furthermore, a valve is provided at the output end of the drain outlet.

[0014] Furthermore, the probe electrode is connected to a data acquisition device via an amplifying circuit.

[0015] The present invention also provides a static calibration method for liquid film thickness using the calibration device, comprising: Obtain different static liquid film thickness measurement values; Obtain the voltage value of the corresponding conductivity probe assembly under different thickness conditions; According to different static liquid film thickness measurement values ​​and the voltage values ​​of the conductivity probe assembly corresponding to different thicknesses, the linear relationship between the static liquid film thickness measurement value and the voltage value of the conductivity probe assembly is obtained to complete the static calibration of the liquid film thickness.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The invention discloses a static calibration device for liquid film thickness, comprising a dish, a liquid film thickness measuring mechanism and a conductivity probe assembly. By arranging a cover plate on the top of the dish and arranging the liquid film thickness measuring mechanism on the cover plate, the liquid film thickness inside the dish is measured. By arranging a drain port at the bottom of the dish, the liquid film thickness inside the dish is changed. By arranging a conductivity probe assembly containing two parallel probe electrodes, the voltage of the conductivity probe assembly under different liquid film thickness conditions inside the dish is acquired. By arranging a data acquisition device, the measurement data of the liquid film thickness measuring mechanism and the voltage acquisition data of the conductivity probe assembly are acquired. Finally, by arranging a data analysis device, the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode is calculated according to the voltage at both ends of the probe electrode and the measurement value of the liquid film thickness measuring mechanism, thereby completing the static calibration of the liquid film thickness. By statically calibrating the thickness of the liquid film before measuring the thickness of the gas-liquid two-phase flow liquid film, a mathematical relationship between the liquid film thickness and the voltage value of the conductivity probe assembly can be established. In the actual measurement process, the actual thickness of the liquid film can be obtained based on the established mathematical relationship and the real-time voltage value of the conductivity probe assembly. The actual thickness of the liquid film obtained by this method is not affected by the gas-water mixed fluid and the uneven distribution of the liquid film along the circumference of the pipe. The liquid film thickness measurement is more accurate and the data is more reliable, which can provide a reliable basis for engineers to understand the situation at the bottom of the well and judge the production and liquid production of the oil and gas well.

[0017] By arranging a threaded hole on the top of the wall of the dish and arranging a positioning hole on the cover plate at a position corresponding to the threaded hole, the dish and the cover plate are threadedly connected, the structure is simple and the processing cost is low.

[0018] The conductivity probe assembly also includes a probe base, which is detachably connected to the bottom of the dish; a shell is provided outside the probe electrode, which is fixedly connected to the probe base; a heat shrink tube is provided on the probe electrode sleeve, and the heat shrink tube and the shell are fixedly sealed by structural adhesive, so as to achieve a sealed connection between the conductivity probe assembly and the bottom of the dish.

[0019] The cover plate is provided with an insertion hole for inserting a fixed liquid film thickness measuring mechanism.

[0020] The liquid film thickness measuring mechanism is a micrometer, which has higher measurement accuracy and is easy to adjust, thereby ensuring the accuracy of the subsequent acquisition of the linear relationship between the conductivity probe assembly voltage and the liquid film thickness, and further ensuring the reliability of the final test result.

[0021] When the differential ruler is fixed, the limit distance of the differential ruler head is greater than or equal to the distance from the tail of the differential ruler head to the bottom of the dish, ensuring that the differential ruler can accurately obtain the liquid film thickness.

[0022] The output end of the drain port is provided with a valve, and the thickness of the liquid film in the dish can be adjusted by adjusting the opening of the valve.

[0023] The probe electrode is connected to the data acquisition device via an amplifying circuit, and the weak signal can be effectively amplified by setting the amplifying circuit, thereby improving the strength and readability of the signal acquired by the data acquisition device and improving the efficiency of data acquisition.

[0024] The present invention also provides a static calibration method for liquid film thickness using the calibration device, which obtains different static liquid film thickness measurement values ​​and voltage values ​​of the corresponding conductivity probe assembly under different thickness conditions; then, according to the different static liquid film thickness measurement values ​​and the voltage values ​​of the corresponding conductivity probe assembly under different thickness conditions, the linear relationship between the static liquid film thickness measurement value and the voltage value of the conductivity probe assembly is obtained to complete the static calibration of the liquid film thickness. Through static calibration, the relationship between the voltage value of the conductivity probe assembly and the liquid film thickness is obtained, so that in the subsequent process of measuring the liquid film thickness, the liquid film thickness can be directly obtained according to the relevant linear relationship and the voltage of the conductivity probe assembly. This thickness measurement method is not affected by the fluidity and unevenness of the liquid film, and can more accurately measure the liquid film thickness, providing a reliable basis for engineering and technical personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of a static calibration device for liquid film thickness of the present invention.

[0026] Figure 2 The three views of the dish in the static calibration device of liquid film thickness of the present invention are shown, wherein a is the main view of the dish, b is the left view of the dish, and c is the top view of the dish.

[0027] Figure 3 It is a structural diagram of a cover plate in a static calibration device for liquid film thickness of the present invention, wherein a is a front view of the cover plate and b is a left view of the cover plate.

[0028] Figure 4 It is a structural diagram of a probe base in a static calibration device for liquid film thickness of the present invention, wherein a is a front view of the probe base and b is a left view of the probe base.

[0029] Figure 5 The present invention is a schematic diagram of the conductivity probe assembly installed on the pipe wall during liquid film measurement.

[0030] Figure 6 The present invention is a schematic diagram of the flow chart of a static calibration experimental method for liquid film thickness of the present invention.

[0031] Figure 7 The figure is a calibration experimental data relationship curve diagram of a liquid film thickness static calibration device of the present invention in a specific embodiment of the present invention.

[0032] Among them, 1-dish, 2-cover, 3-positioning hole, 4-insertion hole, 5-liquid film thickness measuring mechanism, 6-threaded hole, 7-differential ruler head, 8-liquid film, 9-drain outlet, 10-leg threaded hole, 11-probe base, 12-conductivity probe assembly, 13-probe electrode, 14-tube wall, 15-heat shrink tube, 16-structural adhesive, 17-housing, 18-amplifying circuit, 19-center hole, 20-probe base through hole, 21-leg, 22-valve, 23-data acquisition equipment, 24-data analysis equipment. DETAILED DESCRIPTION

[0033] In order to make the purpose, 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 in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0040] Example 1 See also Figure 1 , the present invention discloses a static calibration device for liquid film thickness, comprising a dish 1, a cover plate 2, a liquid film thickness measuring mechanism 5 and a conductivity probe assembly 12; The dish 1 is filled with a liquid film 8, and a drain port 9 is provided at the bottom of the dish 1 for adjusting the thickness of the liquid film 8; The cover plate 2 is fixedly connected to the top of the dish 1, and the liquid film thickness measuring mechanism 5 passes through the cover plate 2 and is inserted into the inside of the dish 1 to measure the thickness of the liquid film 8; The conductivity probe assembly 12 is inserted at the bottom of the dish 1 and includes two parallel probe electrodes 13. The probe electrodes 13 are connected to a constant current source for providing a constant current to the conductivity probe assembly 12. The probe electrode 13 and the liquid film thickness measuring mechanism 5 are both connected to a data acquisition device for collecting the voltage at both ends of the probe electrode 13 and the measured value of the liquid film thickness measuring mechanism 5; The data acquisition device is connected to a data analysis device for calculating the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode 13 according to the voltage at both ends of the probe electrode 13 and the measurement value of the liquid film thickness measurement mechanism 5 .

[0041] During calibration, the liquid film thickness is adjusted through the drain port 9. Each time the liquid film thickness is adjusted, a corresponding voltage of the conductivity probe assembly 12 is obtained. Then, all liquid film thicknesses and the voltages of the conductivity probe assembly 12 are collected to obtain a linear relationship between the two, and calibration is completed. When measuring the actual liquid film thickness, the liquid film thickness can be obtained based on the voltage of the conductivity probe assembly 12 and the linear relationship between the two obtained after calibration. This method is not affected by the flow of the liquid film and its uniformity, and the measurement result is more accurate and reliable.

[0042] Example 2 See also Figure 1, the present invention discloses a static calibration device for liquid film thickness, comprising a dish 1, a cover plate 2, a liquid film thickness measuring mechanism 5 and a conductivity probe assembly 12; See also Figure 2 The dish 1 is a cylindrical structure with a liquid film 8 inside. A drain port 9 is provided at the bottom of the dish 1. A valve 22 is provided at the output end of the drain port 9 for adjusting the thickness of the liquid film 8. A leg 21 is provided at the bottom of the dish 1. The leg 21 has a leg threaded hole 10 built in. The leg threaded hole 10 has a screw built in it for adjusting the height and balance of the dish 1. A center hole 19 is opened at the center of the bottom of the dish 1 for installing a conductivity probe assembly 12.

[0043] See also Figure 3 The cover plate 2 is fixedly connected to the top of the dish 1 and is a circular cover plate. A positioning hole 3 is provided on the cover plate 2 at a position corresponding to the threaded hole 6. The positioning hole 3 and the corresponding threaded hole 6 are connected by screws. The cover plate 2 is also provided with an insertion hole 4 for inserting a liquid film thickness measuring mechanism 5. The insertion hole 4 is a strip hole to facilitate the horizontal movement of the liquid film thickness measuring mechanism 5.

[0044] The liquid film thickness measuring mechanism 5 passes through the cover plate 2 and is inserted into the dish 1 to measure the thickness of the liquid film 8; The conductivity probe assembly 12 is inserted into the bottom of the dish and includes a probe base 11 and two parallel probe electrodes 13. Figure 1 and Figure 4 The probe base 11 is detachably connected to the bottom of the dish 1; a shell 17 is provided outside the probe electrode 13, and the shell 17 is fixedly connected to the probe base 11; the probe electrode 13 is sleeved with a heat shrink tube 15, and the heat shrink tube 15 and the shell 17 are fixedly sealed by a structural adhesive 16.

[0045] The probe electrode 13 is connected to a constant current source for providing a constant current to the conductivity probe assembly 12; The probe electrode 13 and the liquid film thickness measuring mechanism 5 are both connected to a data acquisition device 23 for collecting the voltage at both ends of the probe electrode 13 and the measured value of the liquid film thickness measuring mechanism 5; The data acquisition device is connected to a data analysis device 24 for calculating the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode 13 according to the voltage at both ends of the probe electrode 13 and the measurement value of the liquid film thickness measurement mechanism 5 .

[0046] The liquid film thickness measuring mechanism 5 is a differential ruler. When the differential ruler is fixed, the limit distance of the differential ruler head 7 is greater than or equal to the distance from the tail of the differential ruler head 7 to the bottom of the dish 1.

[0047] See also Figure 5, the probe electrode 13 is connected through an amplifying circuit 18 , and when measuring the thickness of the liquid film, the housing 17 is connected to the tube wall 14 .

[0048] Example 3 See also Figure 1 , the present invention discloses a static calibration device for liquid film thickness, comprising a dish 1, a cover plate 2, a liquid film thickness measuring mechanism 5 and a conductivity probe assembly 12; See also Figure 2 The dish 1 is a cylindrical structure with an inner height of 50mm, an inner diameter of 50mm, and a bottom thickness of 10mm. A liquid film 8 is installed inside. A drain port 9 is provided at the bottom of the dish 1. A valve 22 is provided at the output end of the drain port 9 for adjusting the thickness of the liquid film 8; a leg 21 is provided at the bottom of the dish 1. The height of the leg 21 is 15mm. A leg threaded hole 10 is built into the leg 21. The leg threaded hole 10 is an M2 thread. A screw is built into the leg threaded hole 10 for adjusting the height and balance of the dish 1; a center hole 19 is opened at the center of the bottom of the dish 1 for installing a conductivity probe assembly 12.

[0049] See also Figure 3 The cover plate 2 is fixedly connected to the top of the dish 1 and is a circular cover plate. A positioning hole 3 is provided on the cover plate 2 at a position corresponding to the threaded hole 6. The positioning hole 3 and the corresponding threaded hole 6 are connected by screws. The cover plate 2 is also provided with an insertion hole 4 for inserting a liquid film thickness measuring mechanism 5. The insertion hole 4 is a strip hole to facilitate the horizontal movement of the liquid film thickness measuring mechanism 5.

[0050] The liquid film thickness measuring mechanism 5 is a differential ruler, the differential ruler head 7 of which passes through the cover plate 2 and is inserted into the dish 1 to measure the thickness of the liquid film 8; when the differential ruler is fixed, the limit distance of the differential ruler head 7 is greater than or equal to the distance from the tail of the differential ruler head 7 to the bottom of the dish 1; The conductivity probe assembly 12 is inserted into the bottom of the dish and includes a probe base 11 and two parallel probe electrodes 13. Figure 1 and Figure 4The probe base 11 is provided with threads on the outside, and a center hole 19 is provided at the bottom of the dish 1. The center hole 19 is provided with threads that match the external threads of the probe base 11; the probe electrode 13 is provided with a shell 17 on the outside, and the shell 17 is fixedly connected to the probe base 11; the probe electrode 13 is provided with a heat shrink tube 15, and the heat shrink tube 15 and the shell 17 are fixedly sealed by a structural adhesive 16; the probe electrode 13 has an outer diameter of 0.4mm and a length of 14mm. The lateral distance between the two probe electrodes 13 is 1.5mm. The use of a double parallel conductivity probe can avoid interference caused by the ground electrode, and the measurement result is more reliable. It is inserted into a stainless steel shell 17 with an inner diameter of 2mm. Due to the large friction between the two probes due to the extrusion of the heat shrink tube 15, it can be self-fixed. The main body and the probe base 11 are connected and fixed with a structural adhesive 16, and the structural adhesive 16 is squeezed into the gap of the heat shrink tube 15 to ensure the sealing of the probe as a whole.

[0051] The probe electrode 13 and the liquid film thickness measuring mechanism 5 are both connected to a data acquisition device 23 for collecting the voltage at both ends of the probe electrode 13 and the measured value of the liquid film thickness measuring mechanism 5; The data acquisition device is connected to a data analysis device 24 for calculating the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode 13 according to the voltage at both ends of the probe electrode 13 and the measurement value of the liquid film thickness measurement mechanism 5 .

[0052] When the calibration test is performed, when the conductivity probe assembly 12 is inserted into the dish 1 to measure the thickness of the gas-liquid two-phase flow liquid film 8 in the tube, the resistance of this section of the liquid film 8 between the two probe electrodes 13 decreases as the thickness of the liquid film increases. Therefore, a constant current source is added to the two electrodes, and the voltage output at both ends can be measured to calculate the resistance, and the thickness of the liquid film can be calculated by the resistance. The inter-electrode resistance is converted into voltage through the measuring circuit, and then analyzed in the computer collected by the acquisition card. The resistance value variation range of the two probe electrodes 13 in water is 1K~40KΩ, and the voltage can be collected by the acquisition card, and then the corresponding relationship between the voltage and the thickness of the liquid film can be calculated after calibration. The resistance value variation of the two probe electrodes 13 in water can be converted into voltage representation by a circuit device, and the acquisition card collects the voltage, and then the corresponding relationship between the voltage and the thickness of the liquid film 8 can be calculated after calibration.

[0053] See also Figure 5 The probe electrode 13 is connected to a data acquisition device 23 and a data analysis device 24 via an amplifier circuit 18 . When measuring the thickness of the liquid film, the housing 17 is connected to the tube wall 14 .

[0054] See also Figure 6 The present invention provides a static calibration method for liquid film thickness using the above calibration device, comprising: S1: Obtain different static liquid film thickness measurement values; S2: Obtaining the voltage value of the conductivity probe assembly 12 under different thickness conditions; S3: According to different static liquid film thickness measurement values ​​and the voltage values ​​of the conductivity probe assembly 12 corresponding to different thicknesses, a linear relationship between the static liquid film thickness measurement value and the voltage value of the conductivity probe assembly 12 is obtained to complete the static calibration of the liquid film thickness.

[0055] The specific operations are: First, turn the differential head 7 so that its measuring head touches the bottom of the dish 1, and record the reading of the differential head 7 at this time; add water, i.e., liquid film 8, into the dish 2, the height of the water surface is slightly lower than the height of the probe electrode 13, and adjust the differential ruler so that its measuring head is out of the water surface; connect the data acquisition device 23 and the data analysis device 24 to the conductivity probe assembly, and record the voltage data; slowly rotate the differential head 7, and when the differential ruler head 7 touches the water surface, the voltage data will change suddenly, and record the reading of the differential head 7 at this time again, and obtain the voltage data at this time by subtracting it from the first reading of the differential head 7. The thickness of the liquid film 8 is recorded. The thickness of the liquid film 8 and the corresponding voltage value are recorded. A portion of the water in the dish 1 is slowly drawn out through the drain port 9 to reduce the thickness of the liquid film. The differential head 7 is adjusted to contact the water surface. The difference between the differential head 7 reading and the first reading is calculated to obtain the thickness of the liquid film 8. The corresponding liquid film thickness and voltage value are recorded at this time. Repeat the above operation until the water in the dish 1 can no longer form a complete liquid film 8. The voltage values ​​corresponding to different liquid film thicknesses are the experimental data of the static calibration experiment. Through analysis, it is found that there is a linear relationship between the output voltage and the liquid film thickness.

[0056] See also Figure 7 , through the linear relationship fitting curve between the liquid film thickness and the output voltage, the linear relationship expression is obtained as follows:

[0057] Among them, δ is the liquid film thickness, in mm; U is the output voltage, in V; It should be noted that the above specific embodiment test results are given to further illustrate the operation process of the present invention, and cannot be used to indicate that all calibration test results are the same. Without departing from the central idea, it is suitable for calibration before liquid film thickness testing in different fields to ensure the accuracy of subsequent test results.

[0058] In summary, the present invention provides a static calibration device and method for liquid film thickness. By combining the point-to-probe assembly 12 with the liquid film thickness measuring mechanism 5 to set up a calibration experimental device, when the liquid is in a non-flowing state, the liquid film thickness can be measured while the output voltage value can be obtained, and the mathematical relationship between the liquid film thickness and the voltage value output by the acquisition device is successfully established, which lays the foundation for accurately measuring the thickness of the liquid film in the tube in the experiment. The device has the characteristics of simple structure and easy assembly. The calibration method has short steps, simple operation process, and is easy to implement. When the actual liquid film thickness is measured after calibration in this way, the influence of the liquid film flow on the measurement result is greatly reduced, making the measurement result more accurate.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. A static calibration device for liquid film thickness, characterized in that: The invention comprises a dish (1), wherein a cover plate (2) is arranged on the top of the dish (1), and a liquid film thickness measuring mechanism (5) is inserted on the cover plate (2); a drain port (9) is arranged on the bottom of the dish (1); and a conductivity probe assembly (12) is inserted on the bottom of the dish (1); The conductivity probe assembly (12) comprises two parallel probe electrodes (13), and the probe electrodes (13) are connected to a constant current source for providing a constant current to the conductivity probe assembly (12); The probe electrode (13) and the liquid film thickness measuring mechanism (5) are both connected to a data acquisition device for collecting the voltage at both ends of the probe electrode (13) and the measurement value of the liquid film thickness measuring mechanism (5); The data acquisition device is connected to a data analysis device for calculating the corresponding relationship between the liquid film thickness and the voltage at both ends of the probe electrode (13) based on the voltage at both ends of the probe electrode (13) and the measurement value of the liquid film thickness measurement mechanism (5).

2. The static calibration device for liquid film thickness according to claim 1, characterized in that: The top of the wall of the dish (1) is provided with a threaded hole (6); and a positioning hole (3) is provided on the cover plate (2) at a position corresponding to the threaded hole (6).

3. The static calibration device for liquid film thickness according to claim 1, characterized in that: The conductivity probe assembly (12) further comprises a probe base (11), wherein the probe base (11) is detachably connected to the bottom of the dish (1); and a shell (17) is disposed outside the probe electrode (13), wherein the shell (17) is fixedly connected to the probe base (11).

4. The static calibration device for liquid film thickness according to claim 3, characterized in that: The probe electrode (13) is sleeved with a heat shrink tube (15), and the heat shrink tube (15) and the housing (17) are fixed and sealed by a structural adhesive (16).

5. The static calibration device for liquid film thickness according to claim 1, characterized in that: The cover plate (2) is provided with an insertion hole (4) for inserting a fixed liquid film thickness measuring mechanism (5).

6. The static calibration device for liquid film thickness according to claim 1, characterized in that: The liquid film thickness measuring mechanism (5) is a micrometer.

7. The static calibration device for liquid film thickness according to claim 6, characterized in that: When the differential ruler is fixed, the limit distance of the differential ruler head (7) is greater than or equal to the distance from the tail of the differential ruler head (7) to the bottom of the dish (1).

8. The static calibration device for liquid film thickness according to claim 1, characterized in that: A valve (22) is provided at the output end of the drain port (9).

9. The static calibration device for liquid film thickness according to any one of claims 1 to 8, characterized in that: The probe electrode (13) is connected to a data acquisition device via an amplifying circuit (18).

10. A static calibration method for liquid film thickness using the calibration device according to any one of claims 1 to 9, characterized in that: include: Obtain different static liquid film thickness measurement values; Obtaining voltage values ​​of the conductivity probe assembly (12) corresponding to different thickness conditions; According to different static liquid film thickness measurement values ​​and the voltage values ​​of the conductivity probe assembly (12) corresponding to different thicknesses, a linear relationship between the static liquid film thickness measurement value and the voltage value of the conductivity probe assembly (12) is obtained, thereby completing the static calibration of the liquid film thickness.

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