Device for measuring gas content of gas-liquid two-phase flow in pipe based on image recognition

Abstract

The utility model relates to the technical field of measuring devices, in particular to an in-pipe gas-liquid two-phase flow gas content measuring device based on image recognition. The light source and the high-speed camera are respectively arranged on two sides of the transparent tube; the light equalizing assembly is arranged between the light source and the transparent tube; the light equalizing assembly comprises a diffusion plate which is fixed through a support. The two ends of the transparent pipe are communicated with the connecting pipe, and the connecting pipe is arranged on the base in a sliding mode through the sliding rail. Fixing seats are arranged at the two ends of the base, the fixing seats are connected with telescopic pipes in a sealed mode, the telescopic pipes are driven by air cylinders, the fixing seats are provided with connectors communicated with the telescopic pipes, and the connecting pipes are communicated with the telescopic pipes. The non-intrusive real-time measurement can be carried out on the gas content of the gas-liquid two-phase flow in the pipe.

Description

Technical Field

[0001] The utility model relates to the technical field of measuring devices, and specifically relates to a gas-liquid two-phase flow gas holdup measuring device in a pipe based on image recognition. Background Technique

[0002] Gas-liquid two-phase flow widely exists in industrial processes such as energy, power, oil and gas, and chemical industry. Its gas holdup, that is, the gas volume fraction, is an important parameter describing the two-phase flow state, and plays a key role in process control, resource utilization and safe production.

[0003] The existing gas holdup measurement methods mainly include separation measurement method, impedance method, electrical capacitance tomography method, γ-ray attenuation method, etc. These methods either cause great interference to the flow, or have high equipment costs, or the measurement accuracy is easily affected by flow patterns, temperature and impurities, and often cannot achieve real-time on-line measurement.

[0004] In recent years, with the development of digital cameras and image processing technologies, two-phase flow measurement technologies based on image recognition have gradually emerged. For example, patent CN103424406A discloses a measurement device based on a single-frame single-exposure image method, which can simultaneously obtain various parameters such as droplet diameter, velocity, concentration and liquid film thickness, but this device does not specifically measure the gas holdup; CN104198328A discloses an optical measurement device for identifying gas-liquid two-phase flow patterns, but its system is complex, and the real-time performance and cost still need to be optimized.

[0005] Therefore, there is an urgent need for a gas-liquid two-phase flow gas holdup measurement method in a pipe with simple structure, non-invasive, good real-time performance and low cost. Content of the Utility Model

[0006] In order to solve the technical problems existing in the background technique, the utility model provides a gas-liquid two-phase flow gas holdup measuring device in a pipe based on image recognition, which can perform non-invasive real-time measurement on the gas holdup of gas-liquid two-phase flow in the pipe.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] A gas-liquid two-phase flow gas holdup measuring device in a pipe based on image recognition, comprising:

[0009] A transparent pipe;

[0010] A light source and a high-speed camera, which are respectively arranged on both sides of the transparent pipe;

[0011] A light homogenizing component, which is arranged between the light source and the transparent pipe;

[0012] The light homogenizing component includes:

[0013] The diffuser plate is fixed by a bracket.

[0014] Furthermore, both ends of the transparent tube are communicated with the connecting tube, and the connecting tube is slidably arranged on the base through a slide rail.

[0015] Furthermore, fixed seats are arranged at both ends of the base, a telescopic tube is hermetically connected to the fixed seat, the telescopic tube is driven by a cylinder, an interface communicated with the telescopic tube is opened on the fixed seat, and the connecting tube is communicated with the telescopic tube.

[0016] Furthermore, an air adding component is arranged between the transparent tube and the connecting tube.

[0017] Furthermore, the air adding component includes:

[0018] A tube body that communicates the transparent tube and the connecting tube;

[0019] An air tube is arranged inside the tube body, and the air tube is communicated with an air source.

[0020] Furthermore, a one-way valve is arranged between the air tube and the air source.

[0021] Furthermore, the bracket is provided with a straight groove and a bent groove, and the diffuser plate is inserted into the straight groove or the bent groove.

[0022] Furthermore, the lens of the high-speed camera is aligned with the central section of the transparent tube.

[0023] Furthermore, the light source adopts a high-brightness LED array.

[0024] Advantages of the present utility model:

[0025] (1) Non-invasive: There is no need to insert a sensor into the pipeline, which does not affect the flow characteristics.

[0026] (2) Real-time online: High-frame-rate acquisition and fast image processing can achieve millisecond-level response.

[0027] (3) Simple structure and low cost: Only one high-speed camera and a backlight source are required, avoiding complex systems such as multiple cameras or lasers.

[0028] (4) High measurement accuracy: High-precision gas holdup measurement can be achieved through morphological processing and calibration.

[0029] (5) Wide application range: It can be adapted to the measurement of gas-liquid two-phase flows with different pipe diameters and flow patterns. Description of the Drawings

[0030] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0031] Figure 1 It is a structural schematic diagram of the present utility model Figure 1 ;

[0032] Figure 2 is the structural schematic diagram of the present utility model Figure 2 ;

[0033] Figure 3 is the structural schematic diagram of the light homogenizing component;

[0034] Figure 4 is the structural schematic diagram of the gas adding component.

[0035] In the figure:

[0036] 1. transparent tube, 2. light source, 3. light homogenizing component, 4. high-speed camera, 5. gas adding component, 6. connecting tube, 7. base, 8. slide rail, 9. fixing seat, 10. telescopic tube, 11. air cylinder, 12. interface;

[0037] 301. bracket, 302. diffusion plate, 303. straight groove, 304. bent groove;

[0038] 501. pipe body, 502. air pipe, 503. one-way valve. Specific embodiments

[0039] The present utility model will be further described in detail below with reference to the accompanying drawings.

[0040] A gas-liquid two-phase flow void fraction measuring device in a pipe based on image recognition, the specific structure of which includes a transparent tube 1, and a light source 2 and a high-speed camera 4 are respectively arranged on both sides of the transparent tube 1 to form an optical path detection system spanning the diameter of the transparent tube 1. In specific implementation, the lens of the high-speed camera 4 is aligned with the central cross-section of the transparent tube 1, and the light source 2 adopts a high-brightness LED array.

[0041] The light homogenizing component 3 is arranged between the light source 2 and the transparent tube 1. The light homogenizing component 3 can make the light of the light source 2 evenly distributed, so as to make the backlight of the image collected by the high-speed camera 4 uniform.

[0042] The specific structure of the light homogenizing component 3 includes a diffusion plate 302, and the diffusion plate 302 is fixed by a bracket 301. The lower end of the bracket 301 is fixedly connected to the base 7.

[0043] Moreover, straight grooves 303 and curved grooves 304 are formed on the side surface of the bracket 301, and the straight grooves 303 and curved grooves 304 of the two brackets 301 are arranged oppositely. The diffusion plate 302 can be inserted into the straight groove 303 or the curved groove 304. When the diffusion plate 302 is inserted into the straight groove 303, the diffusion plate 302 is in a straight plate state. When the diffusion plate 302 is inserted into the curved groove 304, the diffusion plate 302 is in an arc-shaped plate state. At this time, the center of the arc formed by the diffusion plate 302 coincides with the center of the transparent tube 1. By adjusting the geometric shape of the diffusion plate 302, the relative position and geometric relationship between the diffusion plate 302 and the transparent tube 1 can be accurately controlled, so as to improve the optical characteristics of the light homogenizing component 3 and ensure that the high-speed camera 4 can capture high-definition images.

[0044] Both ends of the transparent tube 1 are communicated with the connecting tube 6, and the connecting tube 6 is slidably arranged on the base 7 through the slide rail 8. By adjusting the position of the connecting tube 6, transparent tubes 1 of different lengths can be connected. Specifically, in the implementation, fixing seats 9 are arranged at both ends of the base 7, the fixing seats 9 are hermetically connected with telescopic tubes 10, and an air cylinder 11 is arranged between the telescopic ends of the telescopic tubes 10 and the fixing seats 9. The telescopic tube 10 is driven by the air cylinder 11. The fixing seat 9 is provided with an interface 12 communicated with the telescopic tube 10, and the connecting tube 6 is communicated with the telescopic tube 10. The air cylinder 11 can drive the connecting tube 6 through the telescopic tube 10, and when the telescopic tube 10 moves, the interface 12 communicated with the telescopic tube 10 remains fixed, which is convenient for connecting the interface 12 with an external system.

[0045] In order to generate bubbles for measurement experiments in the transparent tube 1. An air adding component 5 is arranged between the transparent tube 1 and the connecting tube 6. The air adding component 5 is located at the liquid inlet end of the transparent tube 1, and the bubbles can flow through the transparent tube 1 together with the liquid.

[0046] The specific structure of the air adding component 5 includes a tube body 501, and the tube body 501 communicates the transparent tube 1 and the connecting tube 6. An air tube 502 is arranged inside the tube body 501, the air tube 502 is concentrically arranged with the tube body 501, and the air outlet end of the air tube 502 faces the transparent tube 1. The air inlet end of the air tube 502 is communicated with a gas source. A one-way valve 503 is arranged between the air tube 502 and the gas source. To prevent the liquid from flowing out of the air tube 502.

[0047] Working method:

[0048] a. A light source 2 with high-brightness backlight is arranged outside the transparent tube 1, and a high-speed camera 4 is installed at the side wall or window of the transparent tube 1 to align with the cross-section to be measured.

[0049] b. The high-speed camera 4 acquires dynamic images of the gas-liquid two-phase flow in the transparent tube 1 at a preset frame rate.

[0050] c. By processing and analyzing the acquired images through an algorithm, the gas holdup of the gas-liquid two-phase flow in the tube can be obtained.

[0051] Taking the above-described ideal embodiments of the present utility model as an inspiration, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this utility model. The technical scope of this utility model is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A device for measuring gas content of gas-liquid two-phase flow in a pipe based on image recognition, characterized in that: include: Transparent tube (1); A light source (2) and a high-speed camera (4) are respectively arranged on two sides of the transparent tube (1); A light-homogenizing component (3) is arranged between the light source (2) and the transparent tube (1); The light-homogenizing component (3) comprises: A diffuser plate (302), wherein the diffuser plate (302) is fixed by a bracket (301).

2. The device for measuring the gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 1, characterized in that: Both ends of the transparent tube (1) are connected to a connecting tube (6), and the connecting tube (6) is slidably arranged on a base (7) via a slide rail (8).

3. The device for measuring the gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 2, characterized in that: Fixed seats (9) are provided at both ends of the base (7); a telescopic tube (10) is sealedly connected to the fixed seat (9); the telescopic tube (10) is driven by a cylinder (11); the fixed seat (9) is provided with an interface (12) in communication with the telescopic tube (10); and the connecting tube (6) is in communication with the telescopic tube (10).

4. The device for measuring the gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 2, characterized in that: An air filling assembly (5) is provided between the transparent tube (1) and the connecting tube (6).

5. The device for measuring the gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 4, characterized in that: The aeration assembly (5) comprises: A tube body (501) connecting the transparent tube (1) and the connecting tube (6); The air pipe (502) is arranged inside the tube body (501), and the air pipe (502) is connected to the air source.

6. The device for measuring gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 5, characterized in that: A one-way valve (503) is provided between the air pipe (502) and the air source.

7. The device for measuring gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 1, characterized in that: The bracket (301) is provided with a straight groove (303) and a curved groove (304), and the diffusion plate (302) is inserted into the straight groove (303) or the curved groove (304).

8. The device for measuring gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 1, characterized in that: The lens of the high-speed camera (4) is aimed at the central cross section of the transparent tube (1).

9. The device for measuring gas content of gas-liquid two-phase flow in a pipe based on image recognition according to claim 1, characterized in that: The light source (2) adopts a high-brightness LED array.

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