An array type air volume measuring device with three groups of independent differential pressure outputs

Abstract

The utility model discloses a kind of array type air volume measuring devices with three groups independent differential pressure output, it is related to air volume measuring device technical field, including the positive pressure pipe assembly and negative pressure pipe assembly installed on air duct, wherein: the positive pressure pipe assembly at least includes positive pressure output pipe;The negative pressure pipe assembly at least includes negative pressure measuring pipe;Further include the ring body fixedly communicated with the negative pressure measuring pipe and the positive pressure output pipe;The two end ports of the negative pressure measuring pipe are conical frustum inlet, while middle part is bundle mouth channel, and the narrow mouth of two conical frustum inlets is distributed to the bundle mouth channel distribution.The utility model air duct design is reasonable and can well solve the problem of dust accumulation in air duct.

Description

Technical Field

[0001] This utility model relates to air volume measurement device technology, specifically an array-type air volume measurement device with three sets of independent differential pressure outputs. Background Technology

[0002] Currently, differential pressure airflow measurement devices widely used in industrial sectors (especially the power industry) face several technical bottlenecks, limiting their measurement accuracy and long-term reliability. These devices are typically designed based on the principle of back-to-back tube velocity measurement. Their core structure consists of two parallel air tubes: the dynamic pressure tube has a beveled end (windward side) that converts airflow velocity energy into pressure energy, generating a positive pressure higher than the static pressure in the duct; the static pressure tube has a flat end that senses the static pressure (negative pressure) within the duct. By measuring the difference in pressure between the two, the airflow velocity can be calculated, and the differential pressure value is positively correlated with the flow velocity.

[0003] However, differential pressure devices face multiple challenges in practical applications:

[0004] Structural and signal limitations: A single device can only output one set of differential pressure signals. Even with multiple differential pressure transmitters, their signals originate from the same header pipe, making it impossible to synchronously acquire multiple independent differential pressure signals. Due to the insufficient length of the straight pipe section in the on-site duct, it is difficult to independently deploy multiple measuring devices within the duct. Furthermore, when multiple devices are installed in succession, airflow interference can lead to measurement distortion, making it impossible to improve system stability simply by increasing the number of devices.

[0005] Poor flow field adaptability: Large boilers have large cross-sectional dimensions of air ducts (which are expanded due to the increase in unit capacity), and the velocity field distribution in the cross section is extremely uneven. In addition, the number of measuring points in some devices is insufficient and the layout is unreasonable, making it difficult to accurately capture the flow field characteristics, which leads to measurement deviations.

[0006] Dust and blockage issues: The gas being measured is often a dust-laden airflow. Dust can easily enter the measuring pipeline, and long-term accumulation can cause pipeline blockage (commonly known as "clogging"), which directly affects the accuracy of the differential pressure signal.

[0007] Low reliability of pressure tapping pipes: The pressure tapping pipes between the differential pressure transmitter and the measuring device are typically tens of meters long and have a small diameter. Connections (such as welded or sealed areas) are prone to leakage or blockage due to manufacturing defects, further exacerbating data distortion. Such problems have repeatedly led to misjudgments of air volume by domestic power units, causing turbine tripping accidents and seriously threatening power production safety.

[0008] Given the special operating conditions of large power plant boilers (large duct size, sensitive to air resistance, high dust content, and uneven flow field), how to design and manufacture an air volume measurement device that combines high precision, anti-clogging, and long life has become a key technical problem that the industry urgently needs to solve. Utility Model Content

[0009] The purpose of this invention is to provide an array-type airflow measurement device with three independent differential pressure outputs to address the aforementioned shortcomings in the prior art.

[0010] To achieve the above objectives, this utility model provides the following technical solution: an array-type airflow measurement device with three sets of independent differential pressure outputs, comprising a positive pressure pipe assembly and a negative pressure pipe assembly installed on the air duct, wherein:

[0011] The positive pressure tube assembly includes at least a positive pressure output tube;

[0012] The negative pressure tube assembly includes at least a negative pressure measuring tube;

[0013] It also includes a ring that is fixedly connected to the negative pressure measuring tube and the positive pressure output tube;

[0014] The negative pressure measuring tube has two conical inlets at both ends and a conical channel in the middle, with the narrow openings of the two conical inlets facing the conical channel.

[0015] Preferably, the axial direction of the negative pressure measuring tube is aligned with the airflow in the duct.

[0016] Furthermore, along the airflow, there are sequentially a positive pressure output tube and a negative pressure measuring tube.

[0017] Preferably, the negative pressure measuring tube is connected to the middle of the conical channel, and the positive pressure output tube is located at the entrance of the conical structure.

[0018] Preferably, the outer side of the air duct is fixedly fitted with a mounting sleeve for fixing the positive pressure output pipe, and the number of positive pressure output pipes is not less than three.

[0019] Preferably, the two positive pressure output tubes are fixedly connected by a three-stage equalization tube arranged in a downward X-shape.

[0020] Preferably, the system also includes a secondary pressure equalization pipe centrally located within the air duct, wherein the positive pressure output pipe and the negative pressure measuring pipe are both connected to the secondary pressure equalization pipe and are located on both sides of the secondary pressure equalization pipe.

[0021] Preferably, it also includes a positive pressure measuring tube, which is symmetrically fixed and connected to a primary pressure equalization tube, and the three are Y-shaped and form a test group;

[0022] The two primary equalizing tubes located on the same positive pressure measuring tube are both fixedly connected to the secondary equalizing tube and are distributed between the two positive pressure output tubes;

[0023] The test group shall consist of no fewer than four groups, symmetrically distributed in pairs, and at the same level as the positive pressure output tube.

[0024] Preferably, the system also includes cleaning rods that are symmetrically distributed about the center of the secondary equalizing pipe and connected to the primary equalizing pipe, wherein the minimum included angle between the primary equalizing pipe and the secondary equalizing pipe is 45°.

[0025] Preferably, the positive pressure measuring tube, the primary equalizing tube, the positive pressure output tube, the negative pressure measuring tube, and the tertiary equalizing tube have the same circumferential diameter, and the circumferential diameter of the secondary equalizing tube is not less than twice the circumferential diameter of the positive pressure measuring tube.

[0026] In the above technical solution, this utility model provides an array-type airflow measurement device with three sets of independent differential pressure outputs. Sixteen positive pressure measuring points are evenly arranged on the cross-section of the air duct. A three-stage pressure equalization structure is used to equalize the pressure at these positive pressure measuring points. Simultaneously, a single-stage pressure equalization design with three negative pressure measuring points is incorporated to achieve accurate measurement of the average wind speed within the air duct. The airflow calculated based on the measurement data exhibits high accuracy and minimal fluctuation. This is attributed to the three sets of independent differential pressure signals derived from the three-stage pressure equalization structure, which not only improves the pressure equalization effect but also enhances system reliability through multi-signal redundancy design, while simultaneously reducing operating costs.

[0027] Furthermore, the air resistance inside the duct is extremely low, and the pipeline layout is mainly vertical or inclined at a large angle, which effectively reduces the possibility of dust accumulation inside the duct.

[0028] Furthermore, a special dust removal and purging device is installed for the secondary pressure equalization tube. By periodically purging with compressed air, measurement stability can be maintained over a long period. More importantly, the dust removal operation can be completed externally without entering the air duct, making it simple and efficient.

[0029] Furthermore, the device employs a staggered, X-shaped ring structure for the three equalizing tubes and features differential pressure signal amplification, further optimizing measurement performance. This design is not only suitable for conventional air ducts but can also be flexibly adapted to complex operating environments such as inside flues, expanding the compatibility of application scenarios. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0031] Figure 1 This is a schematic diagram of the overall cross-sectional structure provided for an embodiment of the present utility model;

[0032] Figure 2 This is a structural schematic diagram of the cross-section of the ring provided in an embodiment of the present utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Positive pressure measuring tube; 2. Primary pressure equalization tube; 3. Secondary pressure equalization tube; 4. Positive pressure output tube; 5. Negative pressure measuring tube; 6. Tertiary pressure equalization tube; 7. Dust removal rod; 8. Mounting sleeve; 9. Air duct; 10. Ring body; 101. Conical inlet; 102. Bundle channel. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0036] Please see Figure 1-2 This utility model provides a technical solution: an array-type airflow measurement device with three independent differential pressure outputs, including a positive pressure pipe assembly and a negative pressure pipe assembly installed on the air duct 9, wherein:

[0037] The positive pressure tube assembly includes at least a positive pressure output tube 4;

[0038] The negative pressure tube assembly includes at least a negative pressure measuring tube 5;

[0039] It also includes a ring 10 that is fixedly connected to the negative pressure measuring tube 5 and the positive pressure output tube 4;

[0040] The two ends of the ring body 10 are frustum inlets 101, while the middle part is a constriction channel 102, and the narrow openings of the two frustum inlets 101 are distributed towards the constriction channel 102.

[0041] Furthermore, in combination Figure 2 As shown, the axial direction of the negative pressure measuring tube 5 is consistent with the airflow of the air duct 9, and the positive pressure output tube 4 and the negative pressure measuring tube 5 are arranged sequentially along the airflow.

[0042] Secondly, the negative pressure measuring tube 5 is connected to the middle of the conical channel 102, and the positive pressure output tube 4 is located at the conical inlet 101.

[0043] Furthermore, the outer side of the air duct 9 is fixedly fitted with a mounting sleeve 8 for fixing the positive pressure output pipe 4, and the number of positive pressure output pipes 4 is not less than three.

[0044] Furthermore, the two positive pressure output tubes 4 are fixedly connected by a three-stage equalization tube 6 arranged in a downward X-shape.

[0045] Furthermore, the above embodiment also includes a secondary pressure equalization pipe 3 centrally located within the air duct 9, with the positive pressure output pipe 4 and the negative pressure measuring pipe 5 both connected to the secondary pressure equalization pipe 3 and distributed on both sides of the secondary pressure equalization pipe 3.

[0046] Secondly, it also includes a positive pressure measuring tube 1, on which a primary equalizing tube 2 is symmetrically fixed and connected, and the three are in a Y shape, forming a test group;

[0047] The two primary equalizing tubes 2 located on the same positive pressure measuring tube 1 are fixedly connected to the secondary equalizing tube 3 and are distributed between the two positive pressure output tubes 4;

[0048] There should be no fewer than four test groups, which should be symmetrically distributed in pairs and at the same level as the positive pressure output tube 4.

[0049] Furthermore, it also includes cleaning rods 7 that are symmetrically distributed about the center of the secondary equalizing pipe 3 and connected through the primary equalizing pipe 2, and the minimum included angle between the primary equalizing pipe 2 and the secondary equalizing pipe 3 is 45°.

[0050] Sixteen positive pressure measuring points are evenly arranged on the cross-section of the duct. A three-stage pressure equalization structure is used to equalize the pressure at these points. Simultaneously, a single-stage pressure equalization design with three negative pressure measuring points enables accurate measurement of the average wind speed within the duct. The duct flow rate calculated based on the measurement data exhibits high accuracy and minimal fluctuation. This is attributed to the three independent differential pressure signals derived from the three-stage pressure equalization structure. This not only improves the pressure equalization effect but also enhances system reliability through multi-signal redundancy design, while simultaneously reducing operating costs.

[0051] This airflow measurement device boasts significant advantages in its structural design: minimal air resistance within the duct, and a predominantly vertical or steeply inclined pipe layout, effectively reducing the possibility of dust accumulation inside the pipes; a dedicated dust removal and purging device is specifically designed for the secondary equalizing pipe 3, which maintains measurement stability over the long term by periodically purging with compressed air. More importantly, the dust removal operation can be performed externally without entering the duct, making it simple and efficient.

[0052] Furthermore, the three equalizing tubes 6 in the device adopt a downward X-shaped staggered ring structure 10 and have differential pressure signal amplification function, further optimizing the measurement performance. This design is not only suitable for conventional air ducts, but can also be flexibly adapted to complex working environments such as inside flues, expanding the compatibility of application scenarios.

[0053] During measurement, the 16 air outlets of the positive pressure measuring pipe 1 are 16 measuring points. The pressure of the 16 measuring points is first balanced in the primary pressure equalization pipe 2, then balanced a second time in the secondary pressure equalization pipe 3, and then transmitted to the three positive pressure output pipes 4. The pressure in the three positive pressure output pipes 4 is balanced a third time in the tertiary pressure equalization pipe 6. The pressure of the three-stage pressure equalization structure is fully balanced.

[0054] As a further embodiment of this utility model, the circumferential diameters of the positive pressure measuring tube 1, the primary equalization tube 2, the positive pressure output tube 4, the negative pressure measuring tube 5, and the tertiary equalization tube 6 are the same, and the circumferential diameter of the secondary equalization tube 3 is not less than twice the circumferential diameter of the positive pressure measuring tube 1.

[0055] It should be noted that, in combination Figure 1 As shown, the distance between the axis of the positive pressure output pipe 4 on the left and right sides and the adjacent left and right sidewalls of the air duct 9 is equal to the distance between the axes of two adjacent positive pressure output pipes 4. The distance between the center of the eight air outlets on the upper and lower sides and the adjacent upper and lower sidewalls of the air duct 9 is equal to 1 / 8 of the height of the air duct 9, and the distance between the center of the remaining eight air outlets and the adjacent upper and lower sidewalls of the air duct 9 is equal to 3 / 8 of the height of the air duct 9. The distance between the center of the eight air outlets on the left and right sides and the adjacent left and right sidewalls of the air duct 9 is equal to 1 / 8 of the width of the air duct 9, and the distance between the center of the remaining eight air outlets and the adjacent left and right sidewalls of the air duct 9 is equal to 3 / 8 of the width of the air duct 9. Each measuring point is set according to the size array of the air duct 9 to optimize the accuracy of the measurement data.

[0056] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An array-type airflow measurement device with three independent differential pressure outputs, characterized in that, Includes positive pressure pipe assemblies and negative pressure pipe assemblies installed on the air duct (9), wherein: The positive pressure tube assembly includes at least a positive pressure output tube (4); The negative pressure tube assembly includes at least a negative pressure measuring tube (5); It also includes a ring (10) that is fixedly connected to the negative pressure measuring tube (5) and the positive pressure output tube (4). The two ends of the ring (10) are frustum entrances (101), while the middle part is a constriction channel (102), and the narrow openings of the two frustum entrances (101) are distributed toward the constriction channel (102).

2. The array-type airflow measurement device with three independent differential pressure outputs according to claim 1, characterized in that, The axial direction of the negative pressure measuring tube (5) is consistent with the airflow of the air duct (9); And along the airflow are the positive pressure output tube (4) and the negative pressure measuring tube (5) in sequence.

3. The array-type airflow measurement device with three independent differential pressure outputs according to claim 2, characterized in that, The negative pressure measuring tube (5) is connected to the middle of the conical channel (102), and the positive pressure output tube (4) is located at the conical inlet (101).

4. The array-type airflow measurement device with three independent differential pressure outputs according to claim 1, characterized in that, The outer side of the air duct (9) is fixedly fitted with an installation sleeve (8) for fixing the positive pressure output pipe (4), and the number of the positive pressure output pipe (4) is not less than three.

5. An array-type airflow measurement device with three independent differential pressure outputs according to claim 4, characterized in that, A three-stage equalization tube (6) with a downward X-shaped staggered distribution is fixedly connected between the two positive pressure output tubes (4).

6. An array-type airflow measurement device with three independent differential pressure outputs according to claim 4, characterized in that, It also includes a secondary equalizing pipe (3) located in the center of the air duct (9), the positive pressure output pipe (4) and the negative pressure measuring pipe (5) are both connected to the secondary equalizing pipe (3) and are located on both sides of the secondary equalizing pipe (3).

7. An array-type airflow measurement device with three independent differential pressure outputs according to claim 6, characterized in that, It also includes a positive pressure measuring tube (1), on which a primary equalizing tube (2) is symmetrically fixed and connected, and the three are Y-shaped and form a test group; The two primary equalizing tubes (2) located on the same positive pressure measuring tube (1) are fixedly connected to the secondary equalizing tube (3) and distributed between the two positive pressure output tubes (4); The test group shall consist of no fewer than four groups, which shall be symmetrically distributed in pairs and shall be on the same horizontal plane as the positive pressure output tube (4).

8. An array-type airflow measurement device with three independent differential pressure outputs according to claim 7, characterized in that, It also includes cleaning rods (7) that are symmetrically distributed about the center of the secondary equalizing pipe (3) and connected through the primary equalizing pipe (2), and the minimum included angle between the primary equalizing pipe (2) and the secondary equalizing pipe (3) is 45°.

9. An array-type airflow measurement device with three independent differential pressure outputs according to claim 8, characterized in that, The positive pressure measuring tube (1), the primary equalizing tube (2), the positive pressure output tube (4), the negative pressure measuring tube (5), and the tertiary equalizing tube (6) have the same circumferential diameter, and the circumferential diameter of the secondary equalizing tube (3) is not less than twice the circumferential diameter of the positive pressure measuring tube (1).

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