Patent Application
20240085224
The present invention relates to a flowrate measurement device. It applies, in particular, to the measurement of the flowrate in wastewater or rainwater pipelines.
Flowrate measurement devices are effective in the following cases: for low liquid flowrates, weakly-variable flowrates, uniform liquids, sealed pipelines, and laminar flows. This is because they can comprise parts, such as propellers, positioned in the liquid flow. For example, fuel pump flow meters are very accurate. However, in cases of liquid flowrates in tens, even hundreds, of litres per second, rapidly-varying flowrates, liquids that can carry solids or waste, open pipelines where the liquid is under an air atmosphere, and turbulent flows, flowrate measurement devices are very inaccurate.
The present invention aims to remedy all or part of these drawbacks.
To this end, the present invention envisions a device for measuring the flowrate of a liquid in a pipeline, which comprises, on a mount fixed to a perimeter of the pipeline:
Thanks to these provisions, the high, rapidly-varying liquid flowrates, that can carry solids or waste at the inlet of the pipeline where the liquid is under an air atmosphere, in turbulent flows, can be measured in a stable and accurate way. The mass, its mount and the angle multiplier perform a role of damping the turbulences and variations in the flowrate. The sensor can therefore make reliable measurements.
In addition, the mass, its mount and the angle multiplier reduce the angle of inclination of the moveable part, in the case where the inlet is in the open air, forcing the liquid to follow a steeper slope and be carried away by a straighter inlet than in the absence of these elements. The amplitude of the flowrates measured is therefore increased.
In some embodiments, the moment of inertia of the mass is higher than the moment of inertia of the moveable part.
The damping and angle reduction effects described above are thus increased.
In some embodiments, the moveable part is rectangular and the device comprises flat side flanks perpendicular to the plane of the moveable part and at a constant distance from the moveable part.
In some embodiments, the distance between the side flanks and the moveable part is less than one tenth of the distance between the side flanks.
Thanks to each of these provisions, the angle travelled by the arm that supports the mass is increased for the same liquid flowrate.
In some embodiments, the angle multiplier comprises a multiplier arm connected to a third rotating shaft secured to the moveable part, and to a fourth rotating shaft secured to the arm supporting the mass, the distance between the first and third shafts being greater than the distance between the second and fourth shafts.
In some embodiments, the angle multiplier is configured such that the ratio of the angle travelled by the arm supporting the mass to the angle travelled by the moveable part is at least equal to two.
In some embodiments, the position sensor comprises an inclinometer.
In some embodiments, the position sensor comprises an accelerometer.
Thanks to each of these provisions, the position sensor comprises no mechanical part exposed to the flow of liquid. Thus, there is no risk of this sensor being clogged.
In some embodiments, the moveable part has a surface at least equal to one tenth of a square metre.
In some embodiments, the mass is greater than one kilogramme.
Thanks to these provisions, the device is suitable for measuring flowrates greater than one hundred litres per second.
Other advantages, aims and particular features of the invention will become apparent from the non-limiting description that follows of at least one particular embodiment of the device that is the subject of the present invention, with reference to drawings included in an appendix, wherein:
The present description is given in a non-limiting way, in which each characteristic of an embodiment can be combined with any other characteristic of any other embodiment in an advantageous way.
Note that
Throughout the description, the term “inner” or “central” refers to being located close to or oriented towards an axis of the pipeline, and “outer” refers to being located farther away from or oriented to the opposite of this axis. The term “top” or “upper” refers to being located at the top in
The pipeline 40 has a section 34 and walls 41 only and partially shown in
The device 20 constitutes, in the figures, an “ND400 equivalent” (acronym for “nominal diameter 400 mm”) valve.
The device 20 comprises a fixed flat frame 21 supporting two vertical side flanks 22, each equipped with two strengthening brackets 23. A moveable part 24 is put into motion around a first rotating shaft 25 by the flow of liquid. An arm 29 is rotatably mobile around a second rotating shaft 32 borne by two flat parts 31 perpendicular to the fixed frame 21. The arm 29 bears, at its extremity opposite the fourth rotating shaft 30, a mass 33 with a moment of inertia preferably higher than the moment of inertia of the moveable part 24. A flat part 26, perpendicular to the moveable part 24, is fixed on this moveable part 24. The flat part 26 bears a third rotating shaft 28 rotatably supporting an extremity of an arm 27. At its other extremity, the arm 27 bears a fourth rotating shaft 30 which supports the arm 29.
Preferably, the distance between the first shaft 25 and third shaft 28 is greater than the distance between the second shaft 32 and fourth shaft 30.
When there is no flow of liquid, the moveable part 24 is vertical, and an axis 35 of the line joining the moveable part and the mounted part 26 is vertical, as shown in
The vertical side flanks 22 have a partially circular shape covering the surface travelled by the vertical sides of the moveable part 24. The radius R (see
The distance between the side flanks 22 and the moveable part 24 is preferably less than one tenth of the distance between the side flanks 22.
When there is no flow of liquid, i.e. a zero flowrate, the axis 36 from the second shaft 32 to the centre of gravity of the assembly formed by the arm 29 and the mass 33 has an angle A2 to the vertical, as shown in
In the presence of a flow of liquid, the axis 35 of the line joining the moveable part and the mounted part 26 has an angle A1 to the vertical, as shown in
In the embodiment shown, for the highest flowrates, when the moveable part is fully raised and the angle A1 is the greatest, the mass 33 is almost vertical to its axis 32, such that it no longer exerts a closing force that would reduce the flowrate passing through the device.
As is understood by reading the description above, the mounted part 26, the arm 27 and the arm 29 form an angle multiplier that transforms the angular movement of the moveable part 26 into an angular movement of the arm 29 supporting the mass 33, this arm 29 travelling through an angle A3-A2 greater than the angle A1 travelled by the moveable part 24.
In some embodiments, the angle multiplier is configured such that the ratio of the angle A3-A2 travelled by the arm 29 supporting the mass 33 to the angle A1 travelled by the moveable part 24 is at least equal to two.
Of course, other combinations of arms in movement make it possible to obtain the same angle multiplier effect and the present invention is therefore not limited to the example of angle multiplier shown in
A sensor 37 of the position of the arm 29 supporting the mass 33 measures the angle A3 and deduces the liquid flowrate, based on a function or a correspondence table stored in memory. For example, the correspondence function for the correspondence between the flowrate measured and the difference between the angle A3 and the angle A2, is a polynomial or exponential function. For example, for the values of A3-A2 angle difference greater than or equal to 10°:
This corresponds to the function
flowrate (I/s)=exp[((A3−A2)/100)*5.5]*11.5−10,
In other embodiments, a table of the correspondence between the angles to the vertical of the moveable part 24 and of the arm 29 is utilised. In the example described in the figures, this correspondence table is:
Examples of dimensions and masses utilised are given below:
With these dimensions, the high, rapidly-varying liquid flowrates, that can carry solids or waste at the inlet of the pipeline where the liquid is under an air atmosphere, in turbulent flows, can be measured in a stable and accurate way.
As shown in the figures, in some embodiments, the mount 21 fixed to a perimeter of the pipeline, and the moveable part 24 form a check valve.
In the figures, the moveable part 24 is rectangular. In other embodiments, the moveable part is not flat and/or is not rectangular. For example, the moveable part 24 is circular or spherical, the flanks 22 therefore having a toroidal internal surface.
In some embodiments, the position sensor 37 comprises an inclinometer. In some embodiments, the position sensor 37 comprises an accelerometer. Thus, the position sensor 37 comprises no mechanical part exposed to the flow of liquid. Thus, there is no risk of this sensor being clogged.
In some embodiments, the moveable part has a surface at least equal to one tenth of a square metre.
| Number | Date | Country | Kind |
|---|---|---|---|
| FR2100847 | Jan 2021 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/052036 | 1/28/2022 | WO |
