Large-caliber gas flow measuring device and method

Abstract

The invention relates to a large-diameter gas flow measuring device and method. The large-diameter gas flow measuring device comprises an inlet collecting pipe, an outlet collecting pipe, a small-diameter pipeline and a flowmeter, and the small-diameter pipeline is connected between the inlet collecting pipe and the outlet collecting pipe; the number of the small-caliber pipelines is more than two, and the specifications of the small-caliber pipelines are consistent; the flowmeter is connected with the small-caliber pipeline and used for measuring the medium flow in the small-caliber pipeline. The device has the advantages of being simple in structure, low in requirement for measuring equipment and installation environment, capable of being secondarily designed according to site conditions and high in applicability. The large-diameter pipeline is divided into a plurality of equivalent small-diameter pipelines, the medium flow in the small-diameter pipelines is measured through the flow meter to obtain the flow value, then the gas flow of the large-diameter pipeline is obtained through calculation, then measurement of the flow of the large-diameter pipeline is achieved, stability is high, and measurement precision is high.

Description

Technical Field

[0001] The invention belongs to the field of pipeline flow measurement, and in particular relates to a large-caliber gas flow measurement device and method. Background Art

[0002] In various fields, it is often necessary to measure the flow rate of large-diameter pipelines that transport fluids. The main difficulty currently exists is: when using conventional flow meters (such as flow orifice plates, bar flow meters, etc.) for direct measurement, a certain length of straight pipe section should be guaranteed before and after the installation position of the flow meter to ensure the stability of the internal flow field of the internal pipeline, thereby obtaining a higher measurement accuracy. The length of the straight pipe section required by the flowmeter is related to the diameter of the pipeline. The larger the diameter of the pipeline, the longer the straight pipe section should be. The resulting problem is: in some sites with small spaces, it is difficult to set up a straight pipe section that meets the measurement requirements; it is not economical to set up a longer straight pipe section just to meet the measurement requirements for straight pipe sections that can be set up.

[0003] In the field of lime rotary kilns, the cooling air used in production is a key factor in ensuring lime cooling and kiln working conditions. As the specifications of the kilns increase, the diameter of the cooling air duct reaches 1.5m. According to the flow meter measurement requirements, the straight pipe section length required must exceed 10m, which is difficult and uneconomical to arrange by conventional means. In fact, the measuring devices currently used on site cannot accurately measure the flow rate, which brings great difficulties to the production adjustment and control of the kiln, and is also an obstacle for the lime plant to achieve the goal of intelligent control.

[0004] In the prior art, application number: 201810060829.9 discloses a flow meter suitable for measuring flow in large-diameter pipelines. By setting a guide plate, a rectifier plate and a rectifier structure, the flow field difference of the large-diameter pipeline is reduced, thereby improving the flow measurement accuracy, and by designing the shape of the detection head of the flow sensor, the measurement accuracy is improved. However, the structure of this flow meter is too complicated, the production cost is high, and it is not conducive to on-site modification. Summary of the invention

[0005] The purpose of the present invention is to provide a large-caliber gas flow measurement device and method to solve the problems existing in the current large-size pipeline flow measurement and reduce the transformation cost.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A large-caliber gas flow measurement device comprises an inlet collecting pipe, an outlet collecting pipe, a small-caliber pipeline and a flow meter, wherein the small-caliber pipeline is connected between the inlet collecting pipe and the outlet collecting pipe; there are more than two small-caliber pipelines, and the specifications of the small-caliber pipelines are consistent; the flow meter is connected to the small-caliber pipeline and is used to measure the medium flow in the small-caliber pipeline.

[0008] The inlet collecting pipe comprises a body and a partition. The body is a reducer with circular ends. One end of the circular reducer is an open structure placed in a homogeneous environment, and the other end is closed and fixedly connected to the partition. A plurality of mounting holes are provided on the partition, and the partition is fixedly connected to the small-diameter pipe through the mounting holes.

[0009] The circular reducer is in the shape of a truncated cone.

[0010] The outlet collecting pipe comprises a body and a partition. The body is a reducing pipe with circular ends. One end of the circular reducing pipe is closed and fixedly connected to the partition. The partition is provided with a plurality of mounting holes. The partition is fixedly connected to the small-diameter pipe through the mounting holes. The other end of the circular reducing pipe is connected to an external pipe or equipment.

[0011] The small-diameter pipeline is a straight circular pipe structure.

[0012] The small-diameter pipes are evenly arranged between the inlet collecting pipe and the outlet collecting pipe.

[0013] The small-diameter pipeline is provided with an opening for installing a flow meter.

[0014] The flow meter is a bar flow meter.

[0015] The number of the flow meters is one or more.

[0016] A large-diameter gas flow measurement method divides a large-diameter pipeline into a number of equivalent small-diameter pipelines, measures the flow of each small-diameter pipeline, and then sums and calculates the flow of the large-size pipeline, specifically including the following steps:

[0017] 1) Calculate the installation length L of the large-diameter pipeline to be tested:

[0018] L=L1+L2+L3 (1)

[0019] In formula (1): L1 is the installation length of the inlet manifold, m; L2 is the installation length of the small-diameter pipe, m; L3 is the installation length of the outlet manifold, m;

[0020] Calculate the radius r of small diameter pipe:

[0021] r=L2 / 2N (2)

[0022] In formula (2): r is the radius of the small-diameter pipe, m; N is the multiple, N ≥ 6;

[0023] Calculate the number of small-diameter pipes n:

[0024] n=Q / (πr 2 ×v) (3)

[0025] In formula (3), n is the number of small-diameter pipes; v is the flow rate of the medium in the pipe, m 3 / s;

[0026] Select the flow meter model according to formula (1) to formula (3);

[0027] 2) Calculate the flow rate Q of the large-diameter pipeline to be tested:

[0028] Q=nq (4)

[0029] In formula (4), Q is the flow rate of the large-diameter pipeline to be measured, m 3 / s; q is the flow rate of small-diameter pipe, m 3 / s; n is the number of small-diameter pipes; the flow rate q of n small-diameter pipes is measured by one or more flow meters, and the flow rate Q of the large-diameter pipe is calculated by formula (4).

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The large-diameter gas flow measurement device divides the large-diameter pipeline into several equivalent small-diameter pipelines. The flow meter measures the medium flow in the small-diameter pipeline to obtain the flow value, and then calculates the large-diameter pipeline gas flow, thereby realizing the measurement of the large-diameter pipeline flow with high stability and high measurement accuracy.

[0032] 2. The large-caliber gas flow measurement device has a simple structure, low requirements for measuring equipment and installation environment, can be redesigned according to on-site conditions, and has strong applicability.

[0033] 3. Large-caliber gas flow measurement devices can effectively solve the problem of limited installation space and difficult layout of flow meters. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the present invention.

[0035] Figure 2 yes Figure 1 Section along line AA Figure 1 .

[0036] Figure 3 yes Figure 1 Section along line AA Figure 2 .

[0037] Figure 4 yes Figure 1 Section along line AA Figure 3 .

[0038] In the figure: 1-inlet collecting pipe 2-small diameter pipe 3-outlet collecting pipe 4-flow meter 5-partition. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0040] See Figure 1 A large-caliber gas flow measurement device includes an inlet collection pipe 1, an outlet collection pipe 3, a small-caliber pipe 2, and a flow meter 4. The small-caliber pipe is connected between the inlet collection pipe 1 and the outlet collection pipe 3, and the inlet collection pipe 1 and the outlet collection pipe 3 are coaxially arranged; there are more than two small-caliber pipes 2, and the specifications of the small-caliber pipes 2 are consistent; the flow meter 4 is connected to the small-caliber pipe 2, and is used to measure the medium flow (gas flow) in the small-caliber pipe 2, and the flow meter 4 is one or more (m). The small-caliber pipe 2 is provided with an opening for installing the flow meter 4, and the position of the opening meets the layout requirements of the flow measurement of the small-caliber pipe 2. The flow meter 4 is a bar-type flow meter, which has the least impact on the flow field and can ensure that the measured pipeline flow is consistent with the flow of other small-caliber pipes 2 to the greatest extent.

[0041] The inlet manifold 1 includes a body and a partition 5. The body is a reducer with round ends and a length of L1. One end of the circular reducer is an open structure with a radius of R1 and is placed in a homogeneous environment, such as an atmospheric environment. The other end has a radius of R2 and is closed and fixedly connected to the partition 5. The partition 5 is provided with a plurality of mounting holes, and the partition 5 is fixedly connected to the small-diameter pipe 2 through the mounting holes. The circular reducer is a truncated cone.

[0042] The structure of the outlet collecting pipe 3 is basically the same as that of the inlet collecting pipe 1, except that the circular reducer has a length of L3, a radius of R2 at one end, is welded and fixed to the small-diameter pipe 2 through a partition 5, and has a radius of R3 at the other end connected to an external pipe or equipment.

[0043] The small-diameter pipes 2 are evenly arranged between the inlet manifold 1 and the outlet manifold 3. The number of small-diameter pipes 2 can be 2, 3, or 5. The distribution method is shown in Figure 2-Figure 4 , the spacing between adjacent small-diameter pipes 2 is the same. The small-diameter pipe 2 is a straight circular pipe structure, and the radius r and the number n can be calculated based on the layout length L2, that is, L2 is greater than N times the diameter of the small-diameter pipe 2; when the bar-type flow meter measures the flow, different measurement accuracies require different straight pipe section lengths, and generally require a distance of 3 times the pipe diameter before and after the bar-type flow meter, that is, N is greater than 6.

[0044] Method for measuring large-diameter pipeline flow using large-diameter gas flow measurement device:

[0045] The measurement principle is to divide the original large-diameter pipeline into several equivalent small-diameter pipelines 2, measure the flow rate of each small-diameter pipeline 2, and obtain the flow rate of the large-size pipeline by summing up the calculation. The small-diameter pipelines 2 are evenly arranged so that the flow rate through each small-diameter pipeline 2 remains consistent. One or more bar-type flow meters 4 are used to measure the flow rate q of n small-diameter pipelines 2, and the flow rate Q of the large-diameter pipeline is obtained by calculation.

[0046] Given that the flow rate of the pipeline to be measured is Q, and the length of the available installation position is L (L = L1 + L2 + L3), where the installation length of the small-diameter pipeline 2 is L2, calculate the radius r of the small-diameter pipeline, and the calculation formula is: r = L2 / 2N; assuming that the medium flow rate in the pipeline is v, calculate the number of small-diameter pipelines 2 n, and the calculation formula is: n = Q / (πr 2 ×v). According to the radius r and flow rate Q / n of the small-diameter pipe 2, a suitable bar flow meter can be selected. During production, the bar flow meter 4 is used to measure the flow rate q of the small-diameter pipe 2, and the large-diameter pipe flow rate Q=nq is calculated.

[0047] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A large-caliber gas flow measurement device, characterized in that: It includes an inlet collecting pipe, an outlet collecting pipe, a small-diameter pipe, and a flow meter. The small-diameter pipe is connected between the inlet collecting pipe and the outlet collecting pipe. There are more than two small-diameter pipes, and the specifications of the small-diameter pipes are consistent. The flow meter is connected to the small-diameter pipe and is used to measure the medium flow in the small-diameter pipe.

2. A large-caliber gas flow measurement device according to claim 1, characterized in that: The inlet collecting pipe comprises a body and a partition. The body is a reducer with circular ends. One end of the circular reducer is an open structure placed in a homogeneous environment, and the other end is closed and fixedly connected to the partition. A plurality of mounting holes are provided on the partition, and the partition is fixedly connected to the small-diameter pipe through the mounting holes.

3. A large-caliber gas flow measurement device according to claim 2, characterized in that: The circular reducer is in the shape of a truncated cone.

4. A large-caliber gas flow measurement device according to claim 1, characterized in that: The outlet collecting pipe comprises a body and a partition. The body is a reducing pipe with circular ends. One end of the circular reducing pipe is closed and fixedly connected to the partition. The partition is provided with a plurality of mounting holes. The partition is fixedly connected to the small-diameter pipe through the mounting holes. The other end of the circular reducing pipe is connected to an external pipe or equipment.

5. A large-caliber gas flow measurement device according to claim 1, characterized in that: The small-diameter pipeline is a straight circular pipe structure.

6. A large-caliber gas flow measurement device according to claim 1, characterized in that: The small-diameter pipes are evenly arranged between the inlet collecting pipe and the outlet collecting pipe.

7. A large-caliber gas flow measurement device according to claim 1, characterized in that: The small-diameter pipeline is provided with an opening for installing a flow meter.

8. A large-caliber gas flow measurement device according to claim 1, characterized in that: The flow meter is a bar flow meter.

9. A large-caliber gas flow measurement device according to claim 1, characterized in that: The number of the flow meters is one or more.

10. A method for measuring large-caliber gas flow rate using the measuring device according to any one of claims 1 to 9, characterized in that: Divide a large-diameter pipeline into several equivalent small-diameter pipelines, measure the flow rate of each small-diameter pipeline, and then sum and calculate the flow rate of the large-size pipeline. The specific steps include: 1) Calculate the installation length L of the large-diameter pipeline to be tested: L=L1+L2+L3 (1) In formula (1): L1 is the installation length of the inlet manifold, m; L2 is the installation length of the small-diameter pipe, m; L3 is the installation length of the outlet manifold, m; Calculate the radius r of small diameter pipe: r=L2 / 2N (2) In formula (2): r is the radius of the small-diameter pipe, m; N is the multiple, N ≥ 6; Calculate the number of small-diameter pipes n: n=Q / (πr 2 ×v) (3) In formula (3), n is the number of small-diameter pipes; v is the flow rate of the medium in the pipe, m 3 / s; Select the flow meter model according to formula (1) to formula (3); 2) Calculate the flow rate Q of the large-diameter pipeline to be tested: Q=nq (4) In formula (4), Q is the flow rate of the large-diameter pipeline to be measured, m 3 / s; q is the flow rate of small-diameter pipe, m 3 / s; n is the number of small-diameter pipes; the flow rate q of n small-diameter pipes is measured by one or more flow meters, and the flow rate Q of the large-diameter pipe is calculated by formula (4).

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