RU2778443C2 - Device and method for measurement of speed and fluid flow rate - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: invention relates to the field of measuring parameters of a flow of fluid flowing through a pipeline. A device and a method for the measurement of a fluid flow speed are proposed. The device contains a deflecting unit connected to the pipeline, which is a sealed tank divided into an inlet chamber and an outlet chamber by a wall mounted essentially at an angle to the main flow direction, while chambers are connected by a channel for the passage of fluid between chambers. In this case, a twisting device is provided in the inlet chamber and/or the outlet chamber, designed to direct the fluid flow around the channel axis between the channel and the inner wall of the sealed tank. At the same time, a guide device is provided in the inlet chamber and/or the outlet chamber, designed to direct the fluid flow inside and along the channel axis. Moreover, a deflecting unit contains a means for measuring the fluid flow speed.

EFFECT: possibility of elimination of the formation of large vortex flows in a measuring channel, reduction in the occurrence of stagnant zones in an inlet chamber, elimination of turbulent vortices, refusal of the use of long rectilinear sections, and reduction in the necessary space for the arrangement of rectilinear sections.

11 cl, 3 dwg

Description

FIELD OF TECHNOLOGY

The invention relates to the field of measuring the parameters of the flow of a fluid flowing through a pipeline. In particular, the invention can be used to measure the flow rate and flow rate of fluids such as oil, gas, water, or combinations thereof.

BACKGROUND OF THE INVENTION

Devices for measuring the velocity of fluids are known from the prior art.

The solutions known from the prior art have disadvantages caused by the presence of a turbulent flow with large vortex flows in the measurement zone, as well as the influence on the measurement results of pipeline turns to the flowmeter, inhomogeneity of the inlets, the presence of protruding parts such as gaskets, flanges and transitions, misalignment of pipelines.

To reduce the influence of flow turbulence in the measurement zone, it is recommended to mount the flowmeter in straight sections without changing the cross section for 10-50 pipe diameters before and after the flowmeter. However, the presence of such large straight sections requires significant material costs and the allocation of additional space for the arrangement of such straight sections. Moreover, the accuracy of maintaining straightness throughout this area must also be observed. On pipelines of small diameters, straightness is in most cases provided automatically. But with an increase in the diameter of the pipeline, it becomes more and more difficult to maintain and control the necessary straightness. Also, the measurement accuracy of the flow meter is affected by low-frequency periodic oscillations associated with hydrostatic head fluctuations, for example, oscillations due to the presence of vortex flow movements when passing curved sections.

The closest analogue of the claimed invention is a technical solution according to RU 2019139464B which proposes a measuring device for measuring the flow rate of a fluid flowing in a pipeline in the main flow direction, containing: a deflecting assembly connected to the pipeline and representing a sealed reservoir divided into an inlet chamber and an outlet camera; wherein the chambers are connected by at least one or two channels for the passage of fluid between the chambers; moreover, the deflecting node contains a means for measuring the flow rate of the fluid passing through at least one or two channels.

In the decision RU 2019139464, in order to eliminate the influence of turbulence on the determination of flow parameters, as a means to eliminate turbulence, a design of a flow meter with a deflecting assembly in the form of a sealed tank with a baffle installed at an angle to the direction of the main flow is proposed.

However, this solution has a number of disadvantages, including: the formation of large vortex flows in the measuring channel; the presence of stagnant zones in the inlet chamber;

the flow of fluid directed to the measuring means contains turbulent turbulences caused by pipeline turns to the flowmeter, inhomogeneity of inlets, the presence of protruding parts such as gaskets, flanges and transitions, misalignment of pipelines.

In order to overcome the above disadvantages, a device is proposed for measuring the flow rate of a fluid flowing in the main direction of flow, containing: a deflecting assembly connected to the pipeline and representing a sealed reservoir, divided into an inlet chamber and an outlet chamber, by a wall installed essentially at an angle to the main direction of flow, while the chambers are connected by a channel for the passage of fluid between the chambers; at the same time, in the inlet chamber and/or the outlet chamber, a swirling means is provided for directing the fluid flow around the axis of the channel between the channel and the inner wall of the sealed reservoir; at the same time in the inlet chamber and/or the outlet chamber there is provided a guiding means for directing the fluid flow along the axis and inside the channel; moreover, the deflecting node contains a means for measuring the flow rate of the fluid passing through at least one channel.

The claimed solution makes it possible to eliminate the formation of large vortex flows in the measuring channel, reduce the appearance of stagnant zones in the inlet chamber, and eliminate turbulent eddies caused by pipeline turns to the flow meter, inhomogeneity of supply lines, the presence of protruding parts such as gaskets, flanges and transitions, misalignment of pipelines.

Moreover, the proposed solution will eliminate the use of long straight sections, and, accordingly, reduce material costs and reduce the required space for arranging straight sections.

SUMMARY OF THE INVENTION

In accordance with the description, a device is proposed for measuring the flow rate of a fluid flowing in the main direction of flow, containing: a deflecting assembly connected to a pipeline and representing a sealed reservoir, divided into an inlet chamber and an outlet chamber, by a wall installed essentially at an angle to the main the direction of flow, while the chambers are connected by a channel for the passage of fluid between the chambers; at the same time, in the inlet chamber and/or the outlet chamber, a swirling means is provided for directing the fluid flow around the axis of the channel between the channel and the inner wall of the sealed reservoir; at the same time in the inlet chamber and/or the outlet chamber there is provided a guiding means for directing the fluid flow along the axis and inside the channel; moreover, the deflecting node contains a means for measuring the flow rate of the fluid passing through at least one channel.

Also provided is a method using the above device for measuring the fluid flow rate.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a schematic sectional view of a fluid flow rate measurement device.

Fig. 2 - a schematic design of the swirling means is shown

Fig. 3 shows a schematic design of the guide means.

IMPLEMENTATION OF THE INVENTION

On FIG. 1 schematically shows a measuring device (100) for measuring the flow rate of a fluid flowing in a conduit (103) in the main flow direction (101) indicated by the arrow. The measuring device comprises a deflecting assembly (102) connected to the pipeline, configured to deflect the fluid medium from the axis of the main flow direction of the pipeline and direct the flow at least into the channel (106). Preferably, the diverter assembly is mounted in a plane substantially perpendicular to the axis of the main flow direction, and is a sealed reservoir mounted downstream of the fluid. The sealed reservoir may be made in the form of a polyhedron or in the form of any body of revolution, preferably, the sealed reservoir may be an elongated cylinder. A sealed tank can consist of several parts, for example, it can be a combination of a polyhedron and a body of revolution connected by a thread or a bolted connection.

The sealed container can be obtained by any method known in the art, such as welding, forging or stamping from a steel sheet. Moreover, the sealed container may also be made of any suitable material that can withstand the pressure of the fluid and have sufficient corrosion resistance, for example, it can be made of a polymer or composite material.

The sealed reservoir is divided into an inlet chamber (104) and an outlet chamber (105) by a wall (111) set substantially at an angle to the main flow direction,

In this case, the chambers (104, 105) are interconnected by a channel (106) having open ends (108, 108') both in the inlet chamber and in the outlet chamber for the passage of fluid between the chambers (104, 105).

In order to measure the fluid flow rate, the deflecting assembly includes means (107) for measuring the fluid flow rate passing through the channel. As the fluid flows through the channel (106), the fluid velocity measuring means (107) enables the flow velocity to be measured in the area between the open ends (108, 108') located substantially in a plane perpendicular to the main flow direction (101). The means (107) for measuring the fluid flow rate is an ultrasonic measuring means or a vortex measuring means.

In the embodiment shown schematically in FIG. 1, the fluid enters in the direction (101) of the main flow through the pipeline (103) to the deflector assembly (102) and enters the inlet chamber (104). Since the inlet chamber (104) is separated from the outlet chamber (105) by a wall (111), the passage of fluid between the chambers can only take place through the channel (106). After the entry of the fluid into the inlet chamber, the fluid flow is first deflected from the main flow direction by the wall (111)-flow (109), and then directed by means of a swirling means (112), around the axis of the channel (106) between the channel and the inner wall of the sealed container (102) swirling flow (110).

The swirling means may be a spiral band having an inner longitudinal edge (112') and an outer longitudinal edge (112'') shown schematically in FIG. 2, wherein the inner longitudinal edge (112') is attached to the outer wall of the channel (106) and the outer longitudinal edge (112'') is attached to the inner wall of the sealed container (102).

In this case, the angle of inclination of the spiral tape is essentially equal to the angle of inclination of the wall (111) installed at an angle to the main direction of flow.

As embodiments of the swirling means, a tangential flow swirler or at least one pipeline installed in a spiral around the channel can be used.

The presence of a swirling means makes it possible to divide large vortex flows into many small ones, as a result of which turbulent eddies are smoothed out, and the standard deviation is reduced and the accuracy of measurements is increased, and the distance traveled by the fluid flow in front of the measuring channel increases, which will eliminate the effect of flow changes caused by pipe bends to the flow meter, inhomogeneous connections, protruding parts such as gaskets, flanges and reducers, and pipe misalignment. This distance is determined by the following formula:

S=p*D*N, where

D - tank diameter;

N is the number of turns of the tape.

Before entering the open end (108) of the channel (106), the swirling flow (110) enters the guide means, which is a set of fixed blades (113) passing in the radial direction from the axis of the channel (106) to the inner wall of the sealed reservoir (102) and fixed around a circle bounded by the inner wall of the sealed container, and shown in Fig. 3.

In this case, the blades (113) are blades bent in the direction opposite (towards) the movement of the swirling fluid flow (110) around the axis of the channel (106) between the channel and the inner wall of the sealed reservoir (102).

In one embodiment, the vane is a segment (115) of a hollow cylinder (116) cut by plane A-A of the hollow cylinder along the axis, the larger radius r _o of the hollow cylinder being equal to half the inner radius R of the sealed container (102).

The blades can be obtained by any other method known from the prior art, for example, stamping, casting, powder metallurgy.

Once on the blades, the swirling flow (110) is directed to the open end (108) of the channel (106) with minimal loss of flow velocity. This eliminates the formation of stagnant zones in the inlet chamber.

It is possible that both the swirling means and the guide means are installed in both the inlet chamber (104) and the outlet chamber (105), such an option can be used in the case of a reverse flow of the fluid.

In order to additionally smooth out fluctuations in the fluid flow rate caused by periodic vortices breaking off from various poorly streamlined elements of the tank (for example, the pipeline inlet into the tank, the transition from the inlet chamber to the channel for the passage of fluid between the chambers), as well as caused by the non-smoothness of the general aerodynamic contour tank in the channel (106) provides for the presence of means (113), leveling the inlet flow, installed in front of the measuring means, such as a honeycomb or a deturbulent grid. These tools will improve the velocity field and reduce the slopes and degrees of turbulence in the flow. It is possible that any of the swirling means, guiding means and leveling means, or a combination thereof, can be installed in both the inlet chamber (104) and the outlet chamber (105), such an option can be used in the case of reverse flow of the fluid.

Also provided is a method for measuring the flow rate of a fluid flowing in the main flow direction, in which the fluid is passed through a device for measuring the speed and flow rate of the fluid flow and gives a reading of the measurement of the fluid flow rate.

Claims (16)

1. A device for measuring the flow rate of a fluid flowing in the main direction of flow, containing: a deflecting assembly connected to the pipeline and representing a sealed reservoir, divided into an inlet chamber and an outlet chamber by a wall installed essentially at an angle to the main flow direction, wherein the chambers are connected by a channel for the passage of fluid between the chambers; at the same time, in the inlet chamber and/or the outlet chamber, a swirling means is provided for directing the fluid flow around the axis of the channel between the channel and the inner wall of the sealed reservoir; at the same time in the inlet chamber and/or the outlet chamber, a guiding means is provided for directing the flow of the fluid inside and along the axis of the channel; moreover, the deflecting node contains a means for measuring the flow rate of the fluid passing through at least one channel. 2. The device according to claim 1, in which the swirling means is a spiral tape having an inner longitudinal edge and an outer longitudinal edge, wherein the inner longitudinal edge is attached to the channel, and the outer longitudinal edge is attached to the inner wall of the sealed container. 3. Apparatus according to claim 2, wherein the angle of inclination of the helical band is substantially equal to the angle of inclination of a wall mounted at an angle to the main flow direction. 4. The device according to claim 1, wherein the swirling means is a tangential flow swirler or at least one conduit installed in a spiral around the channel. 5. The device according to claim 1, in which the guide means is a plurality of fixed blades extending in the radial direction from the axis of the channel to the inner wall of the sealed reservoir and fixed around a circle bounded by the inner wall of the sealed reservoir. 6. The device according to claim. 1, in which the blades are blades bent in the direction towards the movement of the fluid flow around the axis of the channel between the channel and the inner wall of the sealed reservoir. 7. The device according to claim. 1, in which the blade is a segment of a hollow cylinder, obtained by cutting the hollow cylinder along the axis, and the larger radius of the hollow cylinder is equal to half the inner radius of the sealed reservoir. 8. The apparatus of claim 1, wherein the means for measuring the fluid flow rate is an ultrasonic measuring means. 9. The apparatus of claim. 1, wherein the means for measuring the fluid flow rate is a vortex measuring means. 10. The apparatus of claim. 1, in which the channel is provided with a means for leveling the flow field and reducing the level of turbulence in the fluid flow. 11. A method for measuring the flow rate of a fluid flowing in the main flow direction, in which the fluid is passed through the device according to claim 1 and a reading of the measurement of the fluid flow rate is provided.

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