CN215524726U

CN215524726U - Rectifier and flowmeter

Info

Publication number: CN215524726U
Application number: CN202120846373.6U
Authority: CN
Inventors: 罗冬; 童洁; 刘锐; 范少龙; 彭文
Original assignee: Honeywell Control Technology China Co ltd
Current assignee: Honeywell Control Technology China Co ltd
Priority date: 2021-04-23
Filing date: 2021-04-23
Publication date: 2022-01-14
Anticipated expiration: 2031-04-23

Abstract

The present invention provides a rectifier, comprising: a cowling; a core portion which is located inside the cowl, is a rotary body, defines a longitudinal direction in a direction of a rotation axis thereof, has a leading portion and a trailing portion which are respectively close to both ends in the longitudinal direction, and is located downstream of the leading portion in a flow direction of a fluid flowing through the cowl, the leading portion providing a flow-obstructing curved surface which is convex toward an upstream for blocking the fluid flowing to the core portion; and a plurality of vanes disposed around the core between the core and the fairing such that fluid flowing past the plurality of vanes forms a rotational flow. The utility model also relates to a flow meter comprising the rectifier.

Description

Rectifier and flowmeter

Technical Field

The utility model relates to a rectifier and a flow meter comprising the rectifier.

Background

The flowmeter is widely used in various fields, for example, the ultrasonic gas flowmeter can realize non-contact measurement, has the advantages of high measurement precision, wide measurement range, convenient installation and maintenance and the like, and is widely used in the flow measurement field. And the device can be conveniently connected to the current gas composition and used in diagnostic intelligent metering, thereby having expected application prospect. However, ultrasonic gas flow meters are sensitive to flow fields and may require the use of a long upstream straight tube to develop the flow into a symmetrical flow field curve. In addition, similar requirements may exist for other flow meters such as turbine flow meters and the like.

Therefore, a good rectifier is needed for use in the flow meter or in the front end of the flow meter to achieve the desired symmetrical flow field to reduce the length of the upstream straight pipe to save installation space.

SUMMERY OF THE UTILITY MODEL

It is an object of the present invention to solve or at least alleviate at least one of the problems existing in the prior art.

In one aspect, a rectifier is provided, which includes:

a cowling;

a core portion which is located inside the cowl, is a rotary body, defines a longitudinal direction in a direction of a rotation axis thereof, has a leading portion and a trailing portion which are respectively close to both ends in the longitudinal direction, and is located downstream of the leading portion in a flow direction of a fluid flowing through the cowl, the leading portion providing a flow-obstructing curved surface which is convex toward an upstream for blocking the fluid flowing to the core portion; and

a plurality of vanes disposed about the core between the core and the fairing such that fluid flowing through the plurality of vanes forms a rotational flow.

Optionally, in the rectifier, the tail portion has a curved flow guide surface protruding toward the downstream.

Optionally, in the fairings, a longitudinal length of the head portion is less than a longitudinal length of the tail portion.

Alternatively, in the rectifier, the fan blades are straight blades or curved blades connected to at least one of the core and the cowl, and the fan blades are disposed obliquely with respect to a radial direction of the core.

Optionally, the rectifier further comprises: a straightening section downstream of the rectifier, the straightening section including a plurality of parallel aligned straightening channels that allow fluid to pass therethrough.

Optionally, the rectifier further comprises: a reducing structure located between the fairing and the straightening section, the reducing structure having an inner diameter that gradually decreases in the direction of flow.

Optionally, the rectifier further comprises: and the diameter expanding structure is positioned between the diameter reducing structure and the straightening section, and the inner diameter of the diameter expanding structure is gradually increased along the flow direction.

Optionally, the rectifier further comprises: a full circle section downstream of the full circle section, the full circle section comprising a plurality of circular annular full circle channels allowing fluid to pass therethrough, the plurality of circular annular full circle channels being coaxially arranged.

Optionally, the rectifier further comprises: a constant diameter pipe section between the full circle section and the full circle section, the constant diameter pipe section having an inner diameter that is substantially constant along the flow direction.

In another aspect, a flow meter is provided that includes a rectifier as described above.

Drawings

The disclosure of the present invention will become more readily understood with reference to the accompanying drawings. It is to be understood by one of ordinary skill in the art that these drawings are for illustrative purposes only and are not intended as a definition of the limits of the utility model. Moreover, like reference numerals are used to denote like parts throughout the figures, wherein:

fig. 1 is a schematic perspective view of an exemplary rectifier in accordance with an embodiment of the present invention;

FIG. 2 is a longitudinal cross-sectional view of the rectifier shown in FIG. 1 taken vertically along its axial centerline;

fig. 3 is a perspective schematic view of another exemplary rectifier in accordance with an embodiment of the present invention;

FIG. 4 is an exploded perspective view of the commutator shown in FIG. 3; and

fig. 5 is a longitudinal sectional view of the commutator shown in fig. 3 taken vertically along its axial centerline.

Detailed Description

Some embodiments of the utility model will be described in more detail below with reference to the accompanying drawings. Unless clearly defined otherwise herein, the meaning of scientific and technical terms used herein is that which is commonly understood by one of ordinary skill in the art.

In the claims and the description of the present invention, the terms "front" and "rear" may refer to positions upstream and downstream, respectively, in the flow direction of the fluid flowing through the rectifier, unless otherwise specifically indicated.

Fig. 1 and 2 illustrate an exemplary fairing 1 according to an embodiment of the utility model that includes a fairing 11, a core 12 positioned within the fairing 11, and a plurality of vanes 13 disposed around the core 12 between the core 12 and the fairing 11.

The fairing 11 may be a separate cover as shown, or may be a part of the meter body or a part of another pipeline.

The core 12 is a rotational body and defines a longitudinal direction in the direction of the rotational shaft 120, with a head portion 121 and a tail portion 122 respectively near both ends of the longitudinal direction. In some embodiments, the core 12 is located at a central position of the cowl 11, with its axis of rotation 120 substantially coincident with the central axis of the cowl 11. In the flow direction F1 of the fluid flowing through the rectifier 1, the head 121 is located upstream, directly facing the fluid flowing into the rectifier 1, while the tail 122 is located downstream of the head 121. The head 121 provides a flow blocking curved surface 1210 to block fluid flow to the core 12. In some embodiments, flow-blocking curved surface 1210 is a convex surface protruding upstream, which blocks fluid flow to core 12 and directs it to the area where fan blades 13 are located. The tail portion 122 may have a flow directing surface 1220 to direct fluid flowing over the outer surface of the core 12. In some embodiments, the flow guiding curved surface 1220 is convex toward the downstream. In some embodiments, the core 12 integrally provides a streamlined outer surface profile that facilitates the flow of fluid through the rectifier 1 and facilitates the rectifying effect.

In some embodiments, the head 121 and tail 122 of the core 12 are not uniformly shaped, e.g., the tail 122 may be sharper than the head 121. In some embodiments, the head portion 121 and the tail portion 122 each have a maximum diameter at a location proximate to one another, and the maximum diameters are substantially the same, but the longitudinal length of the head portion 121, i.e., the longitudinal distance between the maximum diameter and the minimum diameter of the head portion 121 (i.e., at the forward end of the core provided by the head portion 121), is less than the longitudinal length of the tail portion 122, i.e., the longitudinal distance between the maximum diameter and the minimum diameter of the tail portion 122 (i.e., at the rearward end of the core provided by the tail portion 122). In some embodiments, the core 12 is generally spindle-shaped, oval-shaped, drop-shaped, or the like.

For example, in the illustrated embodiment, the head 121 is generally spherical and the tail 122 is generally bullet-shaped, each having a maximum diameter at a location close to each other, and the maximum diameters are the same, and the longitudinal length L1 of the head 121 is smaller than the longitudinal length L2 of the tail 122, so that the tail 122 is sharper than the head 121. In the illustrated embodiment, there is also a cylindrical intermediate portion 123 between the head portion 121 and the tail portion 122, the intermediate portion 123 having a diameter substantially the same as the largest diameter of the head portion 121 and the tail portion 122. Further, the core 12 may be a hollow structure.

The fan blades 13 may be connected to at least one of the core 12 and the cowl 11. For example, in some embodiments, all of the blades 13 are connected to the core 12 and not to the cowl 11. In some embodiments, one portion of the blades 13 is connected to the core 12 and not to the cowl 11, and the other portion is connected to the cowl 11 and not to the core 12. In the illustrated embodiment, the blades 13 are connected to both the core 12 and the cowl 11, and the inner side edges of the blades 13 are connected and fixed to a longitudinally intermediate portion of the core 12, for example, an intermediate portion 123 between the head portion 121 and the tail portion 122 and/or positions of the head portion 121 and the tail portion 122 that are close to each other. In some embodiments, the connection of fan blades 13 on core 12 may be at a location that avoids flow obstructing curves 1210 and flow guiding curves 1220. The outer edges of the blades 13 are connected and fixed to the inner circumferential surface of the cowl 11. Fan blades 13 may be straight blades (as shown in fig. 1) or curved blades (as shown in fig. 4).

The vanes 13 are arranged obliquely with respect to the radial direction of the core 12, and the shape of the passages formed between the vanes 13 is such that the fluid flowing through the plurality of vanes 13 forms a rotating flow. In this way, the unknown disturbance flow field entering the fairing 11 can be changed into a regular rotating flow field, allowing the asymmetric fluid to be thoroughly mixed thereafter. In addition, as described above, the front convex choke surface 1210 of the core 12 may guide the fluid flowing thereon to the area where the fan blades 13 are located, that is, concentrate the fluid flowing into the middle position in the fairing 1 to the position where the edge fan blades 13 are located, so that the fluid is more fully mixed by the fan blades 13.

A reducing structure 14 may be provided downstream of the region of the fan blades 13, and the reducing structure 14 may be a reducing pipe, the inner diameter of which is gradually reduced along the flow direction F1, which can make the fluid generate a retracting effect to further mix the fluid, so that the asymmetric high-speed flow and the low-speed flow in the fluid are mixed uniformly. In some embodiments, as shown in FIG. 2, the reduced diameter structure 14 is attached directly to the aft end of the cowl 11, wherein the aft portion 122 of the core 12 extends into the reduced diameter structure 14.

An expanding structure 15 may be provided downstream of the diameter-reducing structure 14, and the inner diameter of the expanding structure 15 gradually increases in the flow direction F1. In some embodiments, as shown in fig. 2, the diameter reducing structure 14 and the diameter expanding structure 15 may be integrally formed in the same pipe, and together form a pipe with a gradually contracting and then gradually expanding pipe diameter, similar to a "venturi" form. In some embodiments, the conduit further comprises a section of constant diameter pipe 16 downstream of the expanding structure 15, the inner diameter of which does not substantially vary in the flow direction F1. In some embodiments, as shown in fig. 2, the tail portion 122 of the core 12 extends further into the expanding structure 15.

A straightening section 17 may be provided downstream of the reducing structure 14, such as downstream of the equal diameter pipe section 16, and the straightening section 17 may be configured as a honeycomb structure or a bundle of pipes, etc. to divide the fluid into a plurality of parallel fluid bundles to reduce or eliminate eddies in the fluid. The straightening section 17 may comprise a perforated plate comprising a plurality of parallel arranged straightening channels 170 allowing the fluid to pass therethrough for dividing the fluid into several parallel fluid beams. The plurality of straightening channels 170 may be substantially evenly distributed over the straightening section 17. In some embodiments, the straightening section 17 may be made of a honeycomb or circular or annular perforated plate or any other perforated plate having a desired length to aperture ratio (e.g., greater than 4: 1). The aperture plate may be a single or multi-stage aperture plate or bundle.

It will be appreciated that the plurality of tube sections or segments, including but not limited to the fairing 11, reduced diameter structure 14, enlarged diameter structure 15, equal diameter tube section 16, straight section 17, may be formed separately and then assembled together to form the fairing 1, at least some of the tube sections or segments may be integrally formed in the same duct, or all of the tube sections or segments may be integrally formed as a single unitary duct, depending on the ease of manufacture and fabrication. Where the pipe sections or segments are formed and then assembled together, the separately formed pipe sections or segments can be made to have substantially the same outer diameter and appearance, thereby giving the assembled overall pipe a continuous and consistent appearance.

Fig. 3-5 illustrate another exemplary rectifier 2 according to an embodiment of the present invention. Similar to the aforementioned rectifier 1, the rectifier 2 includes a cowl 21, a core 22 located inside the cowl 21, and a plurality of vanes 23 disposed around the core 22 between the core 22 and the cowl 21. Furthermore, along the flow direction F2 of the fluid, the rectifier 2 may further comprise, in sequence, a reducing structure 24, an expanding structure 25, a constant-diameter pipe section 26 with a substantially constant inner diameter, and a straightening section 27, wherein the reducing structure 24 and the expanding structure 25 combine to form a form similar to a "venturi tube". The reduced diameter structure 24, the enlarged diameter structure 25 and the equal diameter pipe section 26 may be integrally formed in the same conduit 30.

Unlike the rectifier 1, in the rectifier 2, the cowl 21 has a structure that is first reduced in diameter and then enlarged in diameter in the flow direction F2, and the core 22 has an oval or drop shape in which a head portion 221 is directly connected to a tail portion 222 having a longitudinal length greater than that of the head portion 221 and has their respective maximum diameters at the connection. The fan blades 23 in the commutator 2 are curved blades. The tip end portion of the duct 30, in which the diameter reducing structure 24, the diameter expanding structure 25, and the constant diameter pipe section 26 are formed, is divided into a constant diameter pipe section 31, and after assembly, the constant diameter pipe section 31 is positioned between the cowl 21 and the diameter reducing structure 24.

Further, downstream of the straightening section 27, a rounding section 29 is also provided, which rounding section 29 comprises a circular grating plate comprising a plurality of rounding channels 290 allowing fluid to pass therethrough. The cross-section (cross-section perpendicular to the flow direction) of the full-circle channel 290 may be circular. For example, the rounding section 29 may comprise a plurality of concentric circular rounding channels, which may be arranged uniformly in the radial direction or may taper radially from the inside to the outside. Between the rounding section 27 and the rounding section 29 there can also be arranged a constant diameter pipe section 28, the inner diameter of which constant diameter pipe section 28 in the flow direction F2 is essentially constant and serves as a mixing development zone for the fluids.

The rectifier 2 further comprises an outer casing 20, and all the above-mentioned pipe sections or sections of the rectifier 2 can be assembled and mounted in the outer casing 20 as required, and the outer casing 20 is formed at both longitudinal ends (axial ends) thereof with mounting

flanges

201, 202, respectively, for connecting the entire rectifier 2 to the corresponding front-end and/or rear-end device. A cavity region 203 may also be formed in the outer casing 20 downstream of the full circle section 29, the cavity region 203 having a substantially constant inner diameter in the flow direction F2 and serving as a fluid development zone. The

sections

21, 30, 27, 28, 29 may be mounted within the outer housing 20 by a threaded connection, a pinned connection, and/or a snap fit.

Another aspect of the utility model also relates to a flow meter comprising the rectifier described above, more particularly a gas flow meter, especially an ultrasonic gas flow meter, comprising the rectifier described above. The rectifier may be integrated into the flow meter or may be provided independently of the flow meter, e.g. may be provided independently upstream of the flow meter. A flow meter incorporating the rectifier of the present invention will be readily available to those skilled in the art in view of the foregoing disclosure.

The foregoing description of the specific embodiments has been presented only to illustrate the principles of the utility model more clearly and therefore should not be taken as an admission that the principles of the utility model are being clearly illustrated or described. Various modifications or changes to the utility model will be readily apparent to those skilled in the art without departing from the scope of the utility model. It is to be understood that such modifications and variations are intended to be included within the scope of the present invention.

Claims

1. A rectifier, characterized in that it comprises:

a cowling;

2. The rectifier of claim 1 wherein the tail portion has a downstream convex flow guiding curve.

3. The commutator of claim 1 wherein the longitudinal length of the head portion is less than the longitudinal length of the tail portion.

4. The rectifier of claim 1 wherein the fan blades are straight blades or curved blades connected to at least one of the core and the cowling, and the fan blades are disposed obliquely to a radial direction of the core.

5. The rectifier of claim 1, further comprising: a straightening section downstream of the rectifier, the straightening section including a plurality of parallel aligned straightening channels that allow fluid to pass therethrough.

6. The rectifier of claim 5, further comprising: a reducing structure located between the fairing and the straightening section, the reducing structure having an inner diameter that gradually decreases in the direction of flow.

7. The rectifier of claim 6, further comprising: and the diameter expanding structure is positioned between the diameter reducing structure and the straightening section, and the inner diameter of the diameter expanding structure is gradually increased along the flow direction.

8. The rectifier of claim 5, further comprising: a full circle section downstream of the full circle section, the full circle section comprising a plurality of circular annular full circle channels allowing fluid to pass therethrough, the plurality of circular annular full circle channels being coaxially arranged.

9. The rectifier of claim 8, further comprising: a constant diameter pipe section between the full circle section and the full circle section, the constant diameter pipe section having an inner diameter that is substantially constant along the flow direction.

10. A flowmeter characterized in that it comprises a rectifier according to any one of claims 1-9.