Flowmeter detection system and method based on natural gas loop system

Abstract

The invention discloses a flowmeter detection system and method based on a natural gas loop system, the detection system comprises a standard meter unit and a loop gas pulsation monitoring unit, the loop gas pulsation monitoring unit comprises a tracer particle filling unit, a transparent pipeline window unit and a gas pulsation calculation unit, the loop gas pulsation monitoring unit is installed on the gas loop system, the airflow vortex angle of the installation area of the measured flowmeter can be calculated in real time, and the capacity of quantitatively monitoring the airflow pulsation of the natural gas loop system is achieved; the flow field stability of each area of the test section can be calculated and analyzed, and whether the stability degree of the flow field meets the requirements of the detection test can be directly judged according to the calculation result, so that the optimal mounting position of the detected flowmeter is accurately obtained, and the detection efficiency and the experiment reliability of the loop type natural gas flow standard device are effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of measurement and detection, and in particular to a flow meter detection system and a detection method based on a natural gas ring system. Background Art

[0002] When testing the flow meter, a natural gas ring system is generally used. The natural gas ring system includes a natural gas main line, a detection branch line and a non-detection branch line. The inlet end of the detection branch line and the inlet end of the non-detection branch line are connected to the main line through a natural gas upstream manifold, and the inlet and outlet ends of the detection branch line and the outlet end of the non-detection branch line are connected to the main line through a natural gas downstream manifold.

[0003] In the natural gas ring system, the rotation of the centrifuge will cause gas pulsation, resulting in unstable gas flow field in the pipeline. At the same time, since the test section where the flow meter is located is equipped with manifolds before and after, the pulsating airflow will further cause flow field distortion. The existing natural gas ring system reduces airflow pulsation, reduces flow field distortion, and improves flow field stability by installing rectifiers after the manifold and before the flow meter being tested and reserving a sufficiently long upstream straight pipe section. In the actual application process, there are several prominent problems:

[0004] First, the existing natural gas ring system lacks the means to quantitatively monitor the gas flow pulsation of the natural gas ring system.

[0005] Second, the existing natural gas loop system is unable to calculate and analyze the flow field stability of each area of ​​the test section, and is unable to accurately calculate the optimal installation position of the flow meter under different working conditions. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the existing natural gas ring system cannot quantitatively detect gas pulsation. The purpose is to provide a flow meter detection system and detection method based on the natural gas ring system, thereby realizing quantitative detection of gas pulsation in the natural gas ring system.

[0007] The present invention is achieved through the following technical solutions:

[0008] A flow meter detection system based on a natural gas loop system, wherein the flow meter to be detected is connected to a detection branch between an upstream natural gas header and a downstream natural gas header, and the detection system comprises:

[0009] A standard meter unit, the inlet end of which is connected to the natural gas main pipeline, and the outlet end of the standard meter unit is connected to the natural gas upstream manifold;

[0010] A ring gas pulsation monitoring unit, the inlet end of which is connected to the natural gas upstream manifold, and the outlet end of the ring gas pulsation monitoring unit is connected to the inlet end of the flow meter to be tested;

[0011] The loop gas pulsation monitoring unit comprises: a tracer particle filling unit, a transparent pipe window unit and a gas pulsation calculation unit, wherein the inlet end of the tracer particle filling unit is connected to the natural gas upstream manifold, the outlet end of the tracer particle filling unit is connected to the inlet end of the transparent pipe window unit, and the outlet end of the transparent pipe window unit is connected to the inlet end of the flow meter to be tested;

[0012] The tracer particle filling unit is used to pump tracer particles into the natural gas pipeline;

[0013] The gas pulsation calculation unit is used to obtain the regional axial velocity, regional radial velocity and swirl angle of the installation area of ​​the flow meter under test in the area where the tracer particles are located through the transparent pipe window unit.

[0014] Specifically, the tracer particle filling unit includes: a tracer storage unit, a tracer pumping unit and a tracer atomization unit. The tracer storage unit stores the tracer, the inlet end of the tracer pumping unit is connected to the tracer storage unit, the outlet end of the tracer pumping unit is connected to the inlet end of the tracer atomization unit, and the outlet end of the tracer atomization unit is connected to the natural gas pipeline.

[0015] Specifically, the gas pulsation calculation unit includes: a laser control unit, an image processing unit and a data processing unit, and the laser control unit, the image processing unit and the data processing unit are electrically connected;

[0016] The laser control unit is used to emit laser light to the transparent pipeline window unit, and the laser light is used to illuminate the tracer particles located in the natural gas pipeline;

[0017] The image processing unit is used to collect instantaneous spatial position coordinate information of the tracer particles illuminated by the laser;

[0018] The data processing unit is used to calculate the regional axial velocity, the regional radial velocity and the swirl angle of the installation area of ​​the flow meter to be tested according to the coordinate information of the tracer particles.

[0019] Specifically, the laser control unit includes: a laser emitter, a laser synchronizer and a laser power supply, and the laser emitter, the laser synchronizer and the laser power supply are electrically connected.

[0020] Specifically, the standard meter unit includes a turbine flowmeter unit, a pressure transmitter unit and a temperature transmitter unit. The turbine flowmeter unit is connected to the natural gas main pipeline and is used to obtain the standard flow. The pressure transmitter unit and the temperature transmitter unit are connected to the turbine flowmeter unit and are used to monitor the operating condition of the turbine flowmeter unit.

[0021] A flow meter detection method based on a natural gas ring system, based on the flow meter detection system based on a natural gas ring system as described above, the detection method comprises:

[0022] Install the flow meter to be tested and the loop gas pulsation monitoring unit;

[0023] Controlling the tracer particle injection unit to inject tracer particles into the natural gas pipeline;

[0024] The gas pulsation calculation unit is controlled to continuously acquire multiple images at the transparent pipe window unit, and multiple position coordinate information of the tracer particles is obtained after image processing;

[0025] Obtain the particle axial velocity and particle radial velocity of the tracer particle through the position coordinate information; and calculate the regional axial velocity and regional radial velocity;

[0026] Calculate the swirl angle of the installation area of ​​the flow meter under test through the regional axial velocity and the regional radial velocity;

[0027] Set the swirl angle threshold. If the swirl angle is less than or equal to the swirl angle threshold, the output flow field is stable. If the swirl angle is greater than the swirl angle threshold, the output flow field is unstable and the installation position of the flow meter under test is changed until the flow field is stable.

[0028] The flow meter under test is tested through the standard meter unit.

[0029] Specifically, the position coordinate information (x0, y0) and (x1, y1) of the plurality of tracer particles at time t0 and time t1 are obtained through the gas pulsation calculation unit;

[0030] Calculate particle axial velocity for multiple tracer particles and the particle radial velocity

[0031] The arithmetic mean of the axial velocities of multiple particles is calculated and used as the regional axial velocity, and the arithmetic mean of the radial velocities of multiple particles is calculated and used as the regional radial velocity.

[0032] Specifically, the calculation method of the swirl angle is: Where V x ' is the regional axial velocity, V y ' is the regional radial velocity.

[0033] Optionally, multiple swirl angles are acquired continuously, and the arithmetic mean of the multiple swirl angles is used as the swirl angle to be compared with the swirl angle threshold.

[0034] Optionally, the swirl angle threshold is 1°.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] The present invention installs a ring gas pulsation monitoring unit on the gas ring system, which can calculate the airflow swirl angle in the installation area of ​​the measured flow meter in real time, realizes the ability to quantitatively monitor the airflow pulsation of the natural gas ring system, and greatly improves the accuracy and reliability of the natural gas ring flow field stability assessment.

[0037] At the same time, the flow field stability in each area of ​​the test section can be calculated and analyzed, and the calculation results can be used to directly determine whether the stability of the flow field meets the requirements of the test, so as to accurately obtain the optimal installation position of the flow meter being tested, thereby effectively improving the detection efficiency and experimental reliability of the ring-type natural gas flow standard device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings illustrate exemplary embodiments of the present invention and, together with the description thereof, are used to explain the principles of the present invention. These drawings are included to provide a further understanding of the present invention, and the accompanying drawings are included in and constitute a part of this specification and do not constitute a limitation of the embodiments of the present invention.

[0039] Figure 1 It is a structural block diagram of a flow meter detection system based on a natural gas ring system according to the present invention.

[0040] Figure 2 4 is a structural block diagram of a gas pulsation calculation unit according to the present invention.

[0041] Figure 3 It is a flow chart of a flow meter detection method based on a natural gas ring system according to the present invention.

[0042] Figure numerals: 1—standard meter unit, 2—natural gas upstream header, 3—loop gas pulsation monitoring unit, 31—tracer particle filling unit, 32—transparent pipeline window unit, 33—gas pulsation calculation unit, 331—laser control unit, 332—image processing unit, 333—data processing unit, 4—tested flow meter, 5—natural gas downstream header. DETAILED DESCRIPTION

[0043] To make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific implementation methods described herein are only used to explain the relevant content, rather than to limit the present invention.

[0044] It should also be noted that, for the convenience of description, only the parts related to the present invention are shown in the drawings.

[0045] In the absence of conflict, the embodiments and features of the embodiments of the present invention may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] To explain the definition of terms, the airflow swirl angle refers to the angle between the velocity vector of a point on the pipe cross section and the pipe axis. It is used to quantitatively characterize the disturbance of the pulsating flow generated by the upstream manifold on the flow field at 4 locations of the downstream flow meter being tested.

[0047] The pulsation frequency is the reciprocal of the time interval between two consecutive peak vortex angles.

[0048] Embodiment 1

[0049] like Figure 1 and Figure 2 As shown, this embodiment provides a flow meter detection system based on a natural gas ring system. The flow meter 4 to be detected is connected to the detection branch between the natural gas upstream manifold 2 and the natural gas downstream manifold 5. The detection system includes a standard meter unit 1 and a ring gas pulsation monitoring unit 3.

[0050] The inlet end of the standard meter unit 1 is connected to the natural gas main line, and the outlet end of the standard meter unit 1 is connected to the natural gas upstream manifold 2; the standard meter unit 1 includes a turbine flowmeter unit, a pressure transmitter unit and a temperature transmitter unit. The turbine flowmeter unit is connected to the natural gas main line and is used to obtain and record the standard flow through the natural gas ring system. The pressure transmitter unit and the temperature transmitter unit are connected to the turbine flowmeter unit and are used to monitor the pressure condition and temperature condition of the turbine flowmeter unit.

[0051] The inlet end of the ring gas pulsation monitoring unit 3 is communicated with the natural gas upstream header 2 , and the outlet end of the ring gas pulsation monitoring unit 3 is communicated with the inlet end of the flow meter 4 to be tested.

[0052] The loop gas pulsation monitoring unit 3 includes: a tracer particle filling unit, a transparent pipe window unit 32 and a gas pulsation calculation unit 33. The inlet end of the tracer particle filling unit is connected to the natural gas upstream header 2, the outlet end of the tracer particle filling unit is connected to the inlet end of the transparent pipe window unit 32, and the outlet end of the transparent pipe window unit 32 is connected to the inlet end of the flow meter 4 to be tested. Tracer particles are pumped into the detection branch through the tracer particle filling unit, and then the gas pulsation calculation unit 33 is non-contactly connected to the transparent pipe window unit 32. The gas pulsation calculation unit 33 can obtain the state of the tracer particles in the detection branch through the transparent structure, so as to calculate the state of the natural gas.

[0053] The tracer particle filling unit is used to pump tracer particles into the natural gas pipeline; the tracer particle filling unit includes: a tracer storage unit, a tracer pumping unit and a tracer atomization unit. The tracer storage unit stores the tracer, the inlet end of the tracer pumping unit is connected to the tracer storage unit, the outlet end of the tracer pumping unit is connected to the inlet end of the tracer atomization unit, and the outlet end of the tracer atomization unit is connected to the natural gas pipeline. The tracer is pumped out through the tracer pumping unit, and after being atomized by the tracer atomization unit, it enters the detection branch and mixes with the natural gas.

[0054] The state of the tracer particles is obtained through the gas pulsation calculation unit 33 , that is, the gas pulsation calculation unit 33 is used to obtain the regional axial velocity, regional radial velocity and swirl angle of the installation area of ​​the flow meter 4 where the tracer particles are located through the transparent pipe window unit 32 .

[0055] The gas pulsation calculation unit 33 includes: a laser control unit 331 , an image processing unit 332 and a data processing unit 333 , and the laser control unit 331 , the image processing unit 332 and the data processing unit 333 are electrically connected.

[0056] The laser control unit 331 is used to emit laser to the transparent pipe window unit 32, and the laser is used to illuminate the tracer particles located in the natural gas pipeline; the laser control unit 331 includes: a laser emitter, a laser synchronizer and a laser power supply, and the laser emitter, the laser synchronizer and the laser power supply are electrically connected to control the frequency, energy and irradiation time of the laser emission in real time. The laser control unit 331 irradiates a natural gas flow field in a certain area in the transparent pipe window unit 32 by emitting a laser sheet light source of a specific frequency, and the tracer particles flowing through the irradiated area will be illuminated by the laser, thereby assisting the image processing unit 332 to obtain the position coordinates of the particles at a certain moment.

[0057] The image processing unit 332 is used to collect the instantaneous position coordinate information of the tracer particles illuminated by the laser; when the tracer particles in the transparent tube window unit 32 are illuminated by the laser of a specific frequency emitted by the laser emitting unit, the image processing unit 332 can record the coordinate information of multiple tracer particles in each millisecond by continuous high-speed photography.

[0058] The data processing unit 333 is used to calculate the regional axial velocity, the regional radial velocity and the swirl angle of the installation area of ​​the flow meter 4 under test according to the coordinate information of the tracer particles. The coordinates of the multiple tracer particles obtained by the image processing unit 332 are screened and continuously calculated to obtain information such as the position change and velocity vector of each tracer particle. Then, the flow field parameters such as the swirl angle of the natural gas in the pipeline at a certain moment can be analyzed and calculated, and whether the stability of the flow field meets the requirements of the loop detection test can be quickly and accurately determined.

[0059] Embodiment 2

[0060] like Figure 3 As shown, this embodiment provides a flow meter detection system based on a natural gas ring system and a flow meter detection method based on a natural gas ring system based on the first embodiment. The detection method includes:

[0061] S1. Install the flow meter 4 and the ring gas pulsation monitoring unit 3.

[0062] The flow meter to be measured is installed at a certain position on the test section, and the tracer particle filling unit 31 is turned on, through the transparent window unit and the gas pulsation calculation unit 33.

[0063] S2. Control the tracer particle filling unit to inject tracer particles into the natural gas pipeline.

[0064] S3, setting the laser emission frequency, energy level and irradiation time through the laser control unit 331, and then adjusting the laser control unit 331 so that the laser sheet light source is vertically projected into the transparent pipe window unit 32.

[0065] S4, controlling the gas pulsation calculation unit 33 to continuously obtain multiple images at the transparent pipe window unit 32, and obtaining the position coordinate information of the tracer particles after image processing; the image processing unit 332 continuously takes high-speed photos to record the coordinate information of the tracer particles within a period of time.

[0066] S5. Obtain the particle axial velocity and particle radial velocity of the tracer particle through the position coordinate information.

[0067] In order to obtain the gas state in the natural gas pipeline more accurately, the position coordinate information (x0, y0) and (x1, y1) of the tracer particles at time t0 and time t1 are obtained by the gas pulsation calculation unit 33; the particle axial velocity of multiple tracer particles is calculated. and the particle radial velocity

[0068] S6. Calculate the arithmetic mean of the axial velocities of the multiple particles and use it as the regional axial velocity; calculate the arithmetic mean of the radial velocities of the multiple particles and use it as the regional radial velocity.

[0069] S7, calculating the swirl angle of the installation area of ​​the flow meter 4 under test by the regional axial velocity and the regional radial velocity; the calculation method of the swirl angle is: Where V x ' is the regional axial velocity, V y ' is the regional radial velocity.

[0070] S8. Continuously obtain multiple swirl angles, and use the arithmetic average of the multiple swirl angles as the swirl angle to be compared with the swirl angle threshold.

[0071] S9, set the swirl angle threshold. If the swirl angle is less than or equal to the swirl angle threshold, the output flow field is stable and jumps to step S10; if the swirl angle is greater than the swirl angle threshold, the output flow field is unstable and the installation position of the flow meter 4 under test is changed and jumps to step S1.

[0072] S10 , the flow meter 4 to be tested is tested by the standard meter unit 1 .

[0073] In this embodiment, the swirl angle threshold is 1°.

[0074] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments / methods or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0075] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0076] It should be understood by those skilled in the art that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above invention, and these changes or modifications are still within the scope of the present invention.

Claims

1. A flow meter detection system based on a natural gas ring system, characterized in that: The flow meter (4) to be tested is connected to a testing branch between an upstream natural gas header (2) and a downstream natural gas header (5), and the testing system comprises: A standard meter unit (1), the inlet end of which is connected to the natural gas main pipeline, and the outlet end of the standard meter unit (1) is connected to the natural gas upstream manifold (2); A ring gas pulsation monitoring unit (3), the inlet end of which is in communication with the natural gas upstream manifold (2), and the outlet end of the ring gas pulsation monitoring unit (3) is in communication with the inlet end of the flow meter (4) to be tested; The loop gas pulsation monitoring unit (3) comprises: a tracer particle filling unit, a transparent pipeline window unit (32) and a gas pulsation calculation unit (33); the inlet end of the tracer particle filling unit is connected to the natural gas upstream manifold (2); the outlet end of the tracer particle filling unit is connected to the inlet end of the transparent pipeline window unit (32); and the outlet end of the transparent pipeline window unit (32) is connected to the inlet end of the flow meter (4) to be tested; The tracer particle filling unit is used to pump tracer particles into the natural gas pipeline; The gas pulsation calculation unit (33) is used to obtain the regional axial velocity, the regional radial velocity and the swirl angle of the installation area of ​​the flow meter (4) to be tested in the area where the tracer particles are located through the transparent pipe window unit (32).

2. A flow meter detection system based on a natural gas ring system according to claim 1, characterized in that: The tracer particle filling unit includes: a tracer storage unit, a tracer pumping unit and a tracer atomization unit. The tracer storage unit stores the tracer, the inlet end of the tracer pumping unit is connected to the tracer storage unit, the outlet end of the tracer pumping unit is connected to the inlet end of the tracer atomization unit, and the outlet end of the tracer atomization unit is connected to a natural gas pipeline.

3. A flow meter detection system based on a natural gas ring system according to claim 1, characterized in that: The gas pulsation calculation unit (33) comprises: a laser control unit (331), an image processing unit (332) and a data processing unit (333), wherein the laser control unit (331), the image processing unit (332) and the data processing unit (333) are electrically connected; The laser control unit (331) is used to emit laser light to the transparent pipeline window unit (32), and the laser light is used to illuminate the tracer particles located in the natural gas pipeline; The image processing unit (332) is used to collect instantaneous spatial position coordinate information of the tracer particles illuminated by the laser; The data processing unit (333) is used to calculate the regional axial velocity, the regional radial velocity and the swirl angle of the installation area of ​​the flow meter (4) to be tested according to the coordinate information of the tracer particles.

4. A flow meter detection system based on a natural gas ring system according to claim 3, characterized in that: The laser control unit (331) comprises: a laser emitter, a laser synchronizer and a laser power supply, and the laser emitter, the laser synchronizer and the laser power supply are electrically connected.

5. A flow meter detection system based on a natural gas ring system according to claim 1, characterized in that: The standard meter unit (1) comprises a turbine flow meter unit, a pressure transmitter unit and a temperature transmitter unit. The turbine flow meter unit is connected to the natural gas main pipeline and is used to obtain a standard flow. The pressure transmitter unit and the temperature transmitter unit are connected to the turbine flow meter unit and are used to monitor the working condition of the turbine flow meter unit.

6. A flow meter detection method based on a natural gas ring system, characterized in that: Based on a flow meter detection system based on a natural gas ring system as claimed in any one of claims 1 to 5, the detection method comprises: Installing a flow meter (4) to be tested and a ring gas pulsation monitoring unit (3); Controlling the tracer particle injection unit to inject tracer particles into the natural gas pipeline; Controlling the gas pulsation calculation unit (33) to continuously acquire multiple images at the transparent pipe window unit (32), and obtaining multiple position coordinate information of the tracer particles after image processing; Obtain the particle axial velocity and particle radial velocity of the tracer particle through the position coordinate information; and calculate the regional axial velocity and regional radial velocity; Calculating the swirl angle of the installation area of ​​the flow meter (4) to be tested by using the regional axial velocity and the regional radial velocity; A swirl angle threshold is set. If the swirl angle is less than or equal to the swirl angle threshold, the output flow field is stable. If the swirl angle is greater than the swirl angle threshold, the output flow field is unstable and the installation position of the flow meter (4) to be tested is changed until the flow field is stable. The flow meter (4) to be tested is tested through a standard meter unit (1).

7. A flow meter detection method based on a natural gas ring system according to claim 6, characterized in that: Obtaining position coordinate information (x0, y0) and (x1, y1) of a plurality of tracer particles at time t0 and time t1 respectively through a gas pulsation calculation unit (33); Calculate particle axial velocity for multiple tracer particles and the particle radial velocity The arithmetic mean of the axial velocities of multiple particles is calculated and used as the regional axial velocity, and the arithmetic mean of the radial velocities of multiple particles is calculated and used as the regional radial velocity.

8. A flow meter detection method based on a natural gas ring system according to claim 6, characterized in that: The calculation method of swirl angle is: Where V x ' is the regional axial velocity, V y ' is the regional radial velocity.

9. A flow meter detection method based on a natural gas ring system according to claim 8, characterized in that: A plurality of swirl angles are continuously acquired, and an arithmetic average of the plurality of swirl angles is used as the swirl angle to be compared with the swirl angle threshold.

10. A flow meter detection method based on a natural gas ring system according to claim 8, characterized in that: The swirl angle threshold is 1°.

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