Flow channel rectifying structure of ultrasonic gas meter

Abstract

The utility model relates to a flow channel rectifying structure of an ultrasonic gas meter. Which comprises an integrally-formed flow channel with a gas inlet end, a fairing combination installed at the gas inlet end and laminar flow sheets for separating the flow channel of the ultrasonic gas meter, and is characterized in that the fairing combination is formed by connecting an avoiding laminar flow sheet type fairing and a coarse rectification type fairing combination. According to the utility model, the coarse rectification type fairing is adopted, external airflow is introduced into the coarse rectification type fairing and is primarily dispersed, and the original distribution of the external airflow is adjusted, so that a primarily uniform flow field is formed in the cavity of the coarse rectification type fairing, and in the process, the gas flow field is redistributed by utilizing the velocity gradient effect of the airflow; the stability of the flow field is further enhanced; finally, under the action of the receding laminar flow sheet type fairing, the airflow is thoroughly rectified and smoothly passes through the rectification sheet, the generation of secondary flow is effectively reduced, and a flow field between the ventilation layer and the transducer signal transmission layer is ensured to reach a stable state.

Description

Technical Field

[0001] This utility model relates to a flow channel rectification structure for an ultrasonic gas meter. Background Technology

[0002] Natural gas, as a widely available energy source, is experiencing increasing demand nationwide due to policies aimed at reducing carbon emissions. Existing gas meters primarily employ a mechanically driven diaphragm structure, transmitting and measuring gas flow mechanically, offering advantages such as simple structure and low cost. However, with technological advancements, diaphragm gas meters are gradually being replaced by more advanced ultrasonic gas meters. Ultrasonic gas meters utilize time-of-flight measurement and non-contact metering, and are widely used in homes and businesses due to their high accuracy, absence of moving parts during operation, and long-term stability in accuracy.

[0003] However, the stability of the gas flow field in ultrasonic gas meters has always been a difficult problem to solve. Especially when the gas flow velocity is between 0.5 m / s and 2 m / s, the inlet valve of the ultrasonic gas meter cannot completely rectify the gas flow effectively. This significantly affects the repeatability of the metering error, resulting in poor gas metering accuracy and potentially failing to meet national standards. This invention improves the stability of the gas flow field and enhances metering accuracy by designing a secondary superimposed rectification device. This device combines two rectification shrouds with different functions into a single unit and installs it at the front end of the inlet of the flow channel. Utility Model Content

[0004] In view of the problems existing in the prior art, the purpose of this utility model is to provide a technical solution for the flow channel rectification structure of an ultrasonic gas meter.

[0005] The flow channel rectification structure of the ultrasonic gas meter includes an integrally formed flow channel with an air inlet end, a rectifier assembly installed at the air inlet end, and laminar flow plates that separate the flow channel of the ultrasonic gas meter. The rectifier assembly is characterized in that it is composed of a laminar flow plate-type rectifier and a coarse rectifier-type rectifier connected together.

[0006] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the outlet end of the coarse rectification shroud is an open groove structure, which forms a coarse rectification shroud cavity with the avoidance laminar flow plate shroud.

[0007] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the rectification shroud assembly is engaged with the integrally formed flow channel including the air inlet end.

[0008] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the avoidance laminar flow plate type rectifier is snapped together with the coarse flow rectifier type rectifier, and the coarse flow rectifier type rectifier is snapped together with the integrally formed flow channel including the air inlet end.

[0009] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the outlet end of the coarse flow rectifier is provided with a coarse flow rectifier sealing boss, and the clearance laminar flow plate rectifier is provided with a clearance laminar flow plate rectifier boss. The coarse flow rectifier sealing boss and the clearance laminar flow plate rectifier sealing surface cooperate to form a coarse flow rectifier cavity; the coarse flow rectifier is provided with coarse flow rectifier sealing bosses on the upper and lower sides. The fairing latch has a groove at the end of the coarse flow fairing latch, which engages with the boss of the clearance layer flow vane fairing. The outlet end of the clearance layer flow vane fairing has a groove-shaped structure, and clearance layer flow vane fairing latch grooves are provided on both the left and right sides of the clearance layer flow vane fairing. The clearance layer flow vane fairing latch grooves engage with the flow channel boss located at the air inlet end.

[0010] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the air inlet end face of the avoidance laminar flow plate type rectifier is provided with B-shaped rectification holes, ordinary rectification ribs and avoidance laminar flow plate type rectifier ribs. There are a plurality of B-shaped rectification holes. Ordinary rectification ribs are arranged between adjacent B-shaped rectification holes. The air inlet end face of the avoidance laminar flow plate type rectifier is provided at the position corresponding to the laminar flow plate in the integrally formed flow channel containing the air inlet end. The height of the avoidance laminar flow plate type rectifier rib is consistent with the maximum thickness of the laminar flow plate.

[0011] The flow channel rectification structure of the ultrasonic gas meter is characterized in that a plurality of A-shaped rectification holes are provided on the air inlet end face of the coarse rectification section of the coarse rectification shroud.

[0012] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the shapes of the A-shaped rectification hole and the B-shaped rectification hole include, but are not limited to, hexagonal, rectangular, grid, and circular shapes, and the ventilation area of ​​the A-shaped rectification hole is larger than that of the B-shaped rectification hole.

[0013] The flow channel rectification structure of the ultrasonic gas meter is characterized in that a plurality of layered flow plates are arranged in the integrally formed flow channel including the air inlet end to divide the flow channel into an air passage layer and a transducer signal transmission layer.

[0014] The flow channel rectification structure of the ultrasonic gas meter is characterized in that the integrally formed flow channel including the air inlet end and the laminar flow plate are integrally formed.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] 1) This utility model adopts a laminar flow plate type fairing. The laminar flow plate type fairing has the same maximum thickness as the laminar flow plate, and the other ribs are smaller than the thickness of the laminar flow plate type fairing. The end face rectifier hole of the laminar flow plate type fairing is a B-shaped rectifier hole, including but not limited to hexagon, rectangle, grid, circle, etc., and has the function of rectifying the gas after primary rectification to the ventilation layer and transducer signal transmission layer before the gas enters the flow channel inlet. This reduces the secondary flow generated by the gas colliding with the front end of the laminar flow plate before entering the flow channel inlet, so that the gas can smoothly enter the interior of the flow channel.

[0017] 2) The outlet end of the coarse rectifier fairing of this utility model is an open groove structure, which forms a cavity between the coarse rectifier fairing cavity and the sealing surface of the avoidance laminar flow plate fairing. The cavity plays a transition rectification role, reducing the material cost of adding an extra transition rectification section.

[0018] 3) This utility model employs a combination of a coarse-flow rectifier and a clearance-layer flow plate rectifier, resulting in a more significant rectification effect. The coarse-flow rectifier initially optimizes the flow field distribution within the ultrasonic gas meter housing. External airflow is introduced into the coarse-flow rectifier, where it is initially dispersed and its original distribution is adjusted, thus forming a preliminary uniform flow field within the cavity of the coarse-flow rectifier. Next, the airflow passes through the cavity of the coarse-flow rectifier, which has a certain thickness. Utilizing the velocity gradient effect of the airflow itself, the gas flow field is redistributed, further enhancing the stability of the flow field. Subsequently, under the action of the clearance-layer flow plate rectifier, the airflow is thoroughly rectified, smoothly passing through the rectifier plates, effectively reducing the generation of secondary flows and ensuring a stable flow field between the ventilation layer and the transducer signal transmission layer. The larger area of ​​the rectification aperture in the coarse-flow rectifier compared to the clearance-layer flow plate rectifier further enhances the effect.

[0019] 3) The air inlet end of the flow channel of this utility model is integrally injection molded with the flow channel. The air inlet end of the flow channel is preferably designed as a flared mouth on both sides, with a certain angle to the side wall of the flow channel. This expands the ventilation area of ​​the flared mouth and can be applied to the rectifier cover with a larger rectification area, reducing the pressure loss of the gas. At the same time, it reduces the overall installation space of the flow channel inside the gas meter, which is conducive to the design of the combined flow channel. Attached Figure Description

[0020] Figure 1 This is an exploded view of the ultrasonic metering module of this utility model;

[0021] Figure 2 This is a cross-sectional view of the overall assembly of the ultrasonic metering module of this utility model.

[0022] Figure 3This is a schematic diagram of the overall assembly of the ultrasonic metering module of this utility model;

[0023] Figure 4 This is an isometric drawing of the coarse-finishing fairing of this utility model.

[0024] Figure 5 This is a cross-sectional view of the coarse-finishing fairing of this utility model;

[0025] Figure 6 This is a cross-sectional axonometric view of the laminar flow-avoiding fairing of this utility model;

[0026] Figure 7 This is a cross-sectional view of the laminar flow avoidance plate fairing of this utility model;

[0027] Figure 8 This is a front view of the laminar flow avoidance plate fairing of this utility model;

[0028] Figure 9 This is a front view of the coarse-finishing fairing of this utility model;

[0029] In the diagram: 1-bend, 2-integrated flow channel including inlet end, 3-inlet end, 4-flow channel boss, 5-laminar flow vane type fairing, 6-coarse flow vane type fairing, 7-stacked positioning hole, 8-stacked fixing pin, 9-embedded copper nut post, 10-through hole, 11-laminar flow vane, 12-ventilation layer, 13-transducer signal transmission layer, 14-inlet end face at coarse flow vane, 15-cavity of coarse flow vane type fairing, 16-inlet at the laminar flow vane. 17-Flow channel air inlet, 18-Flow channel air outlet, 19-Coarse rectifier fairing buckle, 20-A-shaped rectifier hole, 21-Coarse rectifier fairing buckle groove, 22-Coarse rectifier fairing sealing boss, 23-Alignment laminar flow plate type fairing boss, 24-Alignment laminar flow plate type fairing buckle groove, 25-B-shaped rectifier hole, 26-Ordinary rectifier rib, 27-Alignment laminar flow plate type fairing rib, 28-Alignment laminar flow plate type fairing sealing surface. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings:

[0031] like Figure 1 and Figure 2As shown, an ultrasonic gas meter's flow channel rectification structure includes an integrally molded flow channel 2 with an air inlet end, a rectification shroud assembly installed at the air inlet end 3, and laminar flow plates 11 separating the integrally molded flow channel 2 with the air inlet end. The rectification shroud assembly is composed of a laminar flow plate-type rectification shroud 5 with clearance and a coarse rectification shroud 6 connected together. The air inlet end 3 and the flow channel cavity are integrally molded to form the integrally molded flow channel 2 with the air inlet end. Several laminar flow plates 11 are disposed within the integrally molded flow channel 2 with the air inlet end, dividing the integrally molded flow channel 2 with the air inlet end into a ventilation layer 12 and a transducer signal transmission layer 13. The rectification shroud assembly is connected by a snap-fit ​​connection between the laminar flow plate-type rectification shroud 5 with clearance and the coarse rectification shroud 6, with the laminar flow plate-type rectification shroud 5 snap-fit ​​into the integrally molded flow channel 2 with the air inlet end.

[0032] like Figure 4 , Figure 5 As shown, the outlet end of the coarse rectifier 6 is an open groove structure. The open groove structure of the coarse rectifier 6 forms a coarse rectifier cavity 15. The cavity plays a transition rectification role. The outlet end of the coarse rectifier 6 is provided with a coarse rectifier sealing boss 22.

[0033] like Figure 6 , Figure 7 As shown, the outlet end of the evading laminar flow plate type fairing 5 is a groove-shaped structure. The upper and lower sides of the evading laminar flow plate type fairing 5 are provided with evading laminar flow plate type fairing bosses 23, and the left and right sides of the evading laminar flow plate type fairing 5 are provided with evading laminar flow plate type fairing buckle grooves 24.

[0034] like Figure 3 Indication, combined Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, the coarse rectifier shroud sealing boss 22 and the clearance laminar flow plate shroud sealing surface 28 of the clearance laminar flow plate shroud 5 cooperate to form the coarse rectifier shroud cavity 15; coarse rectifier shroud buckles 19 are provided on the upper and lower sides of the coarse rectifier shroud 6, and coarse rectifier shroud buckle groove 21 is provided at the end of the coarse rectifier shroud buckle 19. The coarse rectifier shroud buckle groove 21 is engaged with the clearance laminar flow plate shroud boss 23 on the clearance laminar flow plate shroud 5, and the clearance laminar flow plate shroud buckle groove 24 is engaged with the flow channel boss 4 provided at the air inlet end 3.

[0035] like Figure 8As shown, the air inlet end face 16 of the laminar flow vane type fairing 5 is provided with B-shaped rectifier holes 25, ordinary rectifier ribs 26 and laminar flow vane type rectifier ribs 27. There are several B-shaped rectifier holes 25. Ordinary rectifier ribs 26 are arranged between adjacent B-shaped rectifier holes 25. The end face of the air inlet 16 of the laminar flow vane type fairing 5, which is located at the position corresponding to the laminar flow vane 11, is provided with transverse laminar flow vane type rectifier ribs 27. The height of the laminar flow vane type rectifier ribs 27 is the same as the maximum thickness of the laminar flow vane. The other ribs are smaller than the thickness of the laminar flow vane type rectifier ribs.

[0036] like Figure 9 As shown, the coarse rectifier shroud 6 has several A-shaped rectifier holes 20 on the air inlet end face 14. The shapes of the A-shaped rectifier holes 20 and B-shaped rectifier holes 25 include, but are not limited to, hexagonal, rectangular, grid, and circular. The ventilation area of ​​the A-shaped rectifier holes 20 is larger than that of the B-shaped rectifier holes 25.

[0037] To ensure a better seal between the clearance laminar flow vane 5 and the air inlet end 3, a flow channel boss 4 is provided at the air inlet end 3, connecting to the clearance laminar flow vane 5's left and right sides' clearance laminar flow vane 5's buckle grooves 24. The limiting connection between the flow channel boss 4 and the clearance laminar flow vane 5's buckle grooves 24 ensures that the clearance laminar flow vane ribs 27 and the laminar flow vanes 11 are aligned, thus creating clearance. Meanwhile, the coarse flow vane 6 connects to the clearance laminar flow vane 5's upper and lower clearance laminar flow vane 6 via the coarse flow vane 5's buckle groove 21 on the coarse flow vane buckle 19. The boss 23 is connected, and the two rectifiers are sealed by the coarse rectifier sealing boss 22 and the clearance laminar flow plate rectifier sealing surface 28. The gas enters from the air inlet 14 of the coarse rectifier, which initially disperses the gas in the ultrasonic meter and adjusts its original distribution. After the gas is dispersed and fills the cavity 15 of the coarse rectifier, the gas is rectified again through the air inlet 16 of the clearance laminar flow plate and smoothly enters the transducer signal transmission layer 13 and the ventilation layer 12, ensuring that the flow field between the transducer signal transmission layer 13 and the ventilation layer 12 reaches a stable state.

[0038] like Figure 1 As shown, an ultrasonic gas meter has a flow channel rectification structure in which both the bend 1 and the integrally molded flow channel 2 with the air inlet end are integrally injection molded. The integrally molded flow channel 2 with the air inlet end is connected to the bend end face sealing flange of the bend 1 by screws through the flow channel end face sealing flange. The integrally molded flow channel 2 with the air inlet end and the laminar flow plate 11 are integrally injection molded. Example 1:

[0039] The air inlet end 3 of the integrally formed flow channel 2 with the air inlet end adopts a critical flow nozzle structure to accelerate the gas, such as the air inlet design in the flow channel design of an ultrasonic gas metering in CN202321479483.9. Example 2:

[0040] The air inlet end 3 is preferably configured as a double-flared opening, meaning that the upper and lower structures of the air inlet end 3, parallel to the laminar flow plate, extend from the upper and lower walls of the outer side of the flow channel, maintaining the same height as the flow channel cavity. The left and right sides of the air inlet end 3, perpendicular to the laminar flow plate 11, continue to maintain the characteristics of a critical flow nozzle, and are configured as flared openings. This utility model, by using a single-piece molded double-flared air inlet end 3 with a certain angle to the side wall of the flow channel, expands the ventilation area of ​​the air inlet end 3, making it suitable for shrouds with a larger rectification area and reducing gas pressure loss.

[0041] Working principle:

[0042] This utility model uses the avoidance laminar flow plate type fairing buckle grooves 24 on the left and right sides of the avoidance laminar flow plate type fairing 5 to limit and fix the flow channel bosses 4 on the left and right sides of the air inlet end 3 of the integrated flow channel 2 including the air inlet end. The avoidance laminar flow plate type ribs 27 on the avoidance laminar flow plate type fairing 5 have the same maximum thickness as the laminar flow plates in the integrated flow channel 2 including the air inlet end. Moreover, there are two avoidance laminar flow plate type fairing buckle grooves 24 on the left and right sides of the avoidance laminar flow plate type fairing 5, one above the other. By limiting the flow channel bosses 4, the avoidance laminar flow plate type ribs 27 on the avoidance laminar flow plate type fairing 5 completely cover the laminar flow plates 11 in the flow channel 2 on both sides. This makes it impossible to observe the laminar flow plates 11 inside the flow channel 2 when looking directly at the flow channel from the avoidance laminar flow plate type fairing 5. The remaining ordinary rectifying ribs 26 are smaller than the avoidance laminar flow plate ribs 27, ensuring that the gas, after primary rectification, is thoroughly rectified through the B-shaped rectifying holes 25 between the avoidance laminar flow plate ribs 27, and smoothly passes through the laminar flow plate 11 for metering. In previous designs, the ribs of the rectifier did not avoid the laminar flow plate 11 in the flow channel, causing the gas to be dispersed by the rectifier and easily collide with the front end of the laminar flow plate 11 when entering the flow channel inlet 17, resulting in secondary flow and affecting metering accuracy. The avoidance treatment in this design effectively allows the gas, after primary rectification, to flow smoothly to the ventilation layer 12 and the transducer signal transmission layer 13 before entering the flow channel inlet 17, reducing the secondary flow caused by the gas colliding with the front end of the laminar flow plate 11 before entering the flow channel inlet 17, allowing the gas to pass through the laminar flow plate 11 smoothly. At the same time, the shape of the B-shaped rectifying hole 25 includes, but is not limited to, rectangles, hexagons, grids, circles, etc.

[0043] This invention uses the coarse rectifier buckle groove 21 at the front end of the coarse rectifier buckle 19 on both sides of the coarse rectifier 6 and the avoidance laminar flow plate rectifier boss 23 on both sides of the avoidance laminar flow plate rectifier 5 for limiting and fixing. The coarse rectifier sealing boss 22 and the avoidance laminar flow plate rectifier sealing surface 28 are completely fitted together, forming a coarse rectifier cavity 15 between the coarse rectifier 6 and the avoidance laminar flow plate rectifier 5. This allows two rectifiers with different rectification effects to be stacked to form a novel composite stacked rectification structure. In this design, external airflow is introduced into the coarse rectifier 6, passes through the A-shaped rectification hole 20 on the end face of the coarse rectifier 6 (larger than the avoidance laminar flow plate rectifier 5), and its original distribution is initially dispersed and adjusted, thereby forming a preliminary uniform flow field inside the cavity. Next, the airflow passes through the cavity 15 of the coarse-fiber rectifier 6, which has a certain thickness. During this process, the gas flow field is redistributed by the velocity gradient effect of the airflow itself, further enhancing the stability of the flow field. Finally, under the action of the laminar flow plate rectifier 5, the airflow is thoroughly rectified and passes smoothly through the laminar flow plate 11, effectively reducing the generation of secondary flow and ensuring that the flow field between the ventilation layer 12 and the transducer signal transmission layer 13 reaches a stable state. The shape of the A-shaped rectifier hole 20 on the end face of the coarse-fiber rectifier 6 includes, but is not limited to, hexagonal, rectangular, grid, and circular shapes.

[0044] The specific examples described in this utility model are merely illustrative of the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific examples or use similar methods to replace them, but without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

[0045] Although this utility model uses terms such as ultrasonic meter, flow channel, bend, flare, air inlet, air outlet, rectification structure, laminar flow plate, and secondary flow extensively, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of this utility model; interpreting them as any additional limitation would contradict the spirit of this utility model.

Claims

1. A flow channel rectification structure for an ultrasonic gas meter, comprising an integrally formed flow channel including an air inlet end, a rectification shroud assembly installed at the air inlet end, and laminar flow plates separating the flow channel of the ultrasonic gas meter, characterized in that: The fairing assembly consists of a combination of a laminar flow-avoiding fairing and a coarse flow-avoiding fairing.

2. The flow channel rectification structure of an ultrasonic gas meter according to claim 1, characterized in that... The outlet end of the coarse flow rectifier is an open slot-shaped structure, which forms a cavity between the coarse flow rectifier and the avoidance laminar flow plate rectifier.

3. The flow channel rectification structure of an ultrasonic gas meter according to claim 1, characterized in that... The fairing assembly is engaged with the integrally molded flow channel including the air inlet end.

4. The flow channel rectification structure of an ultrasonic gas meter according to claim 1, characterized in that... The avoidance laminar flow plate type fairing is engaged with the coarse flow type fairing, and the coarse flow type fairing is engaged with the integrally formed flow channel including the air inlet end.

5. The flow channel rectification structure of an ultrasonic gas meter according to claim 4, characterized in that... The coarse rectifier fairing has a sealing boss at its outlet end, and the laminar flow vane fairing has a clearance vane fairing boss. The sealing boss of the coarse rectifier fairing and the sealing surface of the clearance vane fairing cooperate to form a cavity in the coarse rectifier fairing. Coarse rectifier fairing buckles are provided on the upper and lower sides of the coarse rectifier fairing, and the end of the coarse rectifier fairing buckle is provided with a coarse rectifier fairing buckle groove. The coarse rectifier fairing buckle groove engages with the clearance vane fairing boss. The outlet end of the clearance vane fairing has a groove-shaped structure, and clearance vane fairing buckle grooves are provided on the left and right sides of the clearance vane fairing. The clearance vane fairing buckle grooves engage with the flow channel boss provided at the inlet end.

6. The flow channel rectification structure of an ultrasonic gas meter according to claim 5, characterized in that... The air inlet end face of the avoidance laminar flow plate type fairing is provided with B-shaped rectification holes, ordinary rectification ribs and avoidance laminar flow plate type rectification ribs. There are several B-shaped rectification holes. Ordinary rectification ribs are arranged between adjacent B-shaped rectification holes. The air inlet end face of the avoidance laminar flow plate type fairing is provided with transverse avoidance laminar flow plate type rectification ribs at the position corresponding to the laminar flow plate in the integrally formed flow channel containing the air inlet end. The height of the avoidance laminar flow plate type rectification ribs is consistent with the maximum thickness of the laminar flow plate.

7. The flow channel rectification structure of an ultrasonic gas meter according to claim 6, characterized in that... The coarse rectifier fairing has several A-shaped rectifier holes on the air inlet end face of the coarse rectifier section.

8. The flow channel rectification structure of an ultrasonic gas meter according to claim 7, characterized in that... The shapes of the A-shaped rectifier orifice and the B-shaped rectifier orifice include, but are not limited to, hexagonal, rectangular, grid, and circular. The ventilation area of ​​the A-shaped rectifier orifice is larger than that of the B-shaped rectifier orifice.

9. The flow channel rectification structure of an ultrasonic gas meter according to claim 1, characterized in that... The integrally formed flow channel containing the air inlet end is divided into a ventilation layer and a transducer signal transmission layer by several laminar flow plates.

10. The flow channel rectification structure of an ultrasonic gas meter according to claim 1, characterized in that... The integrally molded flow channel and laminar flow plate, including the air inlet end, are integrally molded.

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