FLOW MEASUREMENT APPARATUS

Abstract

The invention relates to a flow measurement apparatus for measuring a parameter, in particular for determining a flow rate, of a flow formed from a fluid, wherein the flow measurement apparatus comprises a flow chamber having an inflow section and an outflow section and a measurement section arranged between the inflow section and the outflow section, wherein the measurement section defines a transport direction for the fluid, wherein at least one ultrasonic device for transmitting and/or receiving ultrasonic waves is arranged in the measurement section. The flow measurement apparatus is characterized in that a flow deflection device is provided that is configured to deflect the flow such that the flow extends at least regionally obliquely to the transport direction in the measurement section, and in that the ultrasonic device is configured to transmit the ultrasonic waves through the fluid in one or more sound paths that are at least substantially perpendicular to the transport direction and/or to receive the ultrasonic waves from the fluid from one or more sound paths that are at least substantially perpendicular to the transport direction.

Claims

1. A flow measurement apparatus for measuring a parameter, of a flow formed from a fluid, wherein the flow measurement apparatus comprises a flow chamber having an inflow section and an outflow section and a measurement section arranged between the inflow section and the outflow section, wherein the measurement section defines a transport direction, wherein at least one ultrasonic device for transmitting and/or receiving ultrasonic waves is arranged in the measurement section, wherein a flow deflection device is provided that is configured to deflect the flow such that the flow extends at least regionally obliquely to the transport direction in the measurement section, and the ultrasonic device is configured to transmit the ultrasonic waves through the fluid in one or more sound paths that are at least substantially perpendicular to the transport direction and/or to receive the ultrasonic waves from the fluid from one or more sound paths that are at least substantially perpendicular to the transport direction.

2. The flow measurement apparatus according to claim 1 that is configured to determine a flow rate.

3. The flow measurement apparatus according to claim 1, wherein the flow deflection device is arranged at least in the inflow section.

4. The flow measurement apparatus according to claim 1, wherein at least one of the sound paths or all the sound paths extends/extend off-center in the measurement section.

5. The flow measurement apparatus according to claim 1, wherein a plurality of mutually parallel sound paths and/or at least two sound paths extending perpendicular to one another are present.

6. The flow measurement apparatus according to claim 1, wherein the flow deflection device has deflection surfaces arranged in the flow chamber.

7. The flow measurement apparatus according to claim 1, wherein the flow deflection device has at least one swirl generator comprising a plurality of blades that extend from a central connection section toward a wall of the flow chamber.

8. The flow measurement apparatus according to claim 7, wherein the blades start at the same position and end at the same position, viewed along the transport direction.

9. The flow measurement apparatus according to claim 8, wherein the blades each have a corresponding geometry.

10. The flow measurement apparatus according to claim 1, wherein the flow deflection device reduces the flow cross-section at its position by less than 15%.

11. The flow measurement apparatus according to claim 1, wherein the flow deflection device reduces the flow cross-section at its position by less than 10%.

12. The flow measurement apparatus according to claim 1, wherein the flow deflection device is configured to deflect the flow such that the deflected flow is axially symmetrical about an axis extending along the transport direction.

13. The flow measurement apparatus according to claim 1, wherein a flow return device is provided that is configured to deflect the deflected flow again such that the flow extends parallel to the transport direction.

14. The flow measurement apparatus according to claim 13, wherein the flow return device is arranged in the outflow section.

15. The flow measurement apparatus according to claim 13, wherein the flow return device corresponds to the flow deflection device.

16. The flow measurement apparatus according to claim 15, wherein the flow return device and the flow deflection device are identical parts.

17. The flow measurement apparatus according to claim 1, wherein the flow measurement apparatus is symmetrical at least with respect to the component that comes into contact with the fluid.

18. The flow measurement apparatus according to claim 1, wherein the flow deflection device comprises at least one supply line which opens into the flow chamber obliquely or transversely to the transport direction and through which a fluid can be introduced into the flow chamber.

19. The flow measurement apparatus according to claim 1, wherein the inflow section, the measurement section and the outflow section together form a pipe and together have a length of less than 1.5 times the pipe diameter.

20. The flow measurement apparatus according to claim 19, wherein the pipe is a straight pipe.

21. The flow measurement apparatus according to claim 21, wherein the pipe has a length of less than 1.2 times the pipe diameter.

22. The flow measurement apparatus according to claim 1, wherein the flow measurement apparatus comprises an evaluation unit that is coupled to the ultrasonic device and that is configured to carry out a transit time difference measurement and to determine the parameter.

23. A method for measuring a parameter of a flow formed from a fluid, wherein the fluid flows in a transport direction, wherein the flow is deflected by means of a flow deflection device such that the flow extends at least regionally obliquely to the transport direction in a measurement section, and ultrasonic waves are transmitted through the fluid in one or more sound paths that are at least substantially perpendicular to the transport direction and/or are received from the fluid from one or more sound paths that are at least substantially perpendicular to the transport direction.

Description

[0063] The invention will be described purely by way of example with reference to the drawings in the following. There are shown:

[0064] FIG. 1 a schematic view of a flow measurement apparatus;

[0065] FIG. 2 a view of a flow deflection device and a flow return device, viewed along the transport direction;

[0066] FIG. 3 a schematic perspective view of the flow deflection device and the flow return device and of the ultrasonic device;

[0067] FIG. 4 the course of the flow through the flow measurement apparatus;

[0068] FIG. 5 a flow measurement apparatus in a perspective view;

[0069] FIG. 6 an embodiment of the flow deflection device with incoming supply lines; and

[0070] FIG. 7 a further embodiment of the flow deflection device comprising a double bend.

[0071] FIG. 1 schematically shows a flow measurement apparatus 10. The flow measurement apparatus 10 comprises an inflow section 12, a measurement section 14 adjoining the inflow section 12 and an outflow section 16 adjoining the measurement section 14. These sections are formed by a continuous pipe 18 that defines a flow chamber 20.

[0072] Two ultrasonic transducers A, B are provided in the measurement section 14 and transmit ultrasonic waves to the respective other transducer A, B. The propagation path of the ultrasonic waves defines a sound path 22 in this respect.

[0073] During operation of the flow measurement apparatus 10, a fluid F, for example natural gas, flows into the inflow section 12 along a transport direction 24. The fluid F is then deflected in the inflow section 12 by a flow deflection device (not shown in FIG. 1) so that the flow of the fluid F extends at least regionally obliquely to the transport direction 24. The inclined course is indicated by an angle ? that defines the angle between the sound path 22 and the course of the deflected flow.

[0074] Based on the fluid F flowing obliquely to the sound path 22, a transit time difference can be measured by means of the transducers A, B, from which transit time difference the volume flowing through the flow measurement apparatus 10 per unit of time can be determined.

[0075] A flow return device (also not shown in FIG. 1) is provided in the outflow section 16 and deflects the oblique course of the deflected flow toward the transport direction 24 again. The fluid F leaves the flow measurement apparatus 10 after the deflection by the flow return device.

[0076] FIG. 2 shows a flow deflection device configured as a swirl generator 26. The swirl generator 26 comprises nine blades 28 arranged rotationally symmetrically around a central connection section 30. The blades 28 originate from the connection section 30 and extend up to a wall 32 of the pipe 18 and in particular merge into the wall 32.

[0077] In FIG. 2, a further swirl generator 34, which serves as a flow return device, can also be partly seen behind the swirl generator 26. The two swirl generators 26, 34 are designed as identical parts, wherein the further swirl generator 34 is inserted into the pipe 18 such that it reduces the cross flow of the deflected fluid F.

[0078] The swirl generators 26, 34 are shown in perspective and in a side view in FIGS. 3 and 4. As can be seen in FIG. 3, between the swirl generators 26, 34, four pairs of transducers A, B are arranged that each define a sound path 22 between them. The transducers A, B are all arranged in one plane in the measurement section 14, to which plane the transport direction 24 forms a normal.

[0079] The flow of the fluid f being formed is shown in FIG. 4. It can be seen that the fluid F flowing in homogenously and in a straight line is deflected by the swirl generator 26 in a direction oblique to the transport direction 24 and also flows through the sound paths 22 in this deflected direction, whereby a measurement is made possible. The further swirl generator 34 then reduces the transverse component of the flow so that the flow flows with a reduced transverse component through the outlet section 16 and leaves it again in the same way.

[0080] FIG. 5 shows a flow measurement apparatus 10 from the outside in a perspective view. The flow measurement apparatus 10 comprises two end faces, one of which is visible in FIG. 5. Boreholes 36 are formed in the end faces and allow a bolting to a pipeline (not shown). The swirl generator 26 is furthermore located directly in the plane formed by the end face so that the swirl generator 26 is arranged at the inlet of the flow measurement apparatus 10. The measurement section 14 is centrally located in the flow measurement apparatus 10, wherein electrical connectors 38 for the transducers A, B can be seen in FIG. 5 that project from a side wall of the flow measurement apparatus 10.

[0081] A fastening flange 40 for evaluation electronics (not shown) is provided on an upper side of the flow measurement apparatus 10.

[0082] The flow measurement apparatus 10 has a symmetrical design so that the flowing through by the fluid F to be measured can take place bidirectionally. Accordingly, the further swirl generator 34 can be arranged flush in the end face not shown in FIG. 5.

[0083] FIGS. 6 and 7 show two further embodiments for the flow deflection device. According to FIG. 6, the flow deflection device comprises two supply lines 42 that open tangentially into the pipe 18. In this respect, the supply lines 42 extend at right angles to the course of the pipe 18 before opening. FIG. 6 shows the course of the flow, wherein it can be seen that the flow is again given a component transverse to the transport direction 24 (i.e. to the direction of extent of the pipe 18).

[0084] According to FIG. 7, the flow deflection device comprises a double bend with two bends 44 about 90? each. The resulting flow is also again shown in FIG. 7. It can be seen that, according to this embodiment, the flow deflection device also deflects the flow such that a kind of swirl or a deflection takes place transversely to the transport direction 24. Due to this deflection, a meaningful measurement of the transit time difference can then take place with the sound paths 22 extending perpendicular to the transport direction 24.

[0085] As can in particular be seen in FIG. 5, the flow measurement apparatus 10 can be very compact since only a very short pipe length has to be provided in the flow measurement apparatus 10 for the transducers A, B. Despite the necessary deflection of the fluid F, it has been shown in practice that very accurate measurements of the flow velocity and thus of the volume flowing through the measurement apparatus 10 are possible.

REFERENCE NUMERAL LIST

[0086] 10 flow measurement apparatus [0087] 12 inflow section [0088] 14 measurement section [0089] 16 outflow section [0090] 18 pipe [0091] 20 flow chamber [0092] 22 sound path [0093] 24 transport direction [0094] 26 swirl generator [0095] 28 blade [0096] 30 connection section [0097] 32 wall [0098] 34 further swirl generator [0099] 36 borehole [0100] 38 connector [0101] 40 fastening flange [0102] 42 supply line [0103] 44 bend [0104] A, B transducer [0105] F fluid [0106] ? angle