Acquatic velocity scanning apparatus and methods

• US 9,823,104 B2
• Filed: 02/21/2013
• Issued: 11/21/2017
• Est. Priority Date: 02/21/2013
• Status: Active Grant

• Current Assignee: Rowe Technologies, Inc.
• Original Assignee: Rowe Technologies, Inc.
• Inventors: Rowe, Francis, Parent, Marc
• Primary Examiner(s): Ratcliffe, Luke
• Assistant Examiner(s): N'Dure, Amie M
• Application Number:
  US13/773,447
• Publication Number:
  US 20140230567A1
• Time in Patent Office: 1,734 Days
• Field of Search: 367 90
• CPC Class Codes: G01F 1/002 wherein the flow is in an open channel
• CPC Class Codes: G01F 1/663 by measuring Doppler frequency shift
• CPC Class Codes: G01F 1/667 Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
• CPC Class Codes: G01S 15/582 using transmission of interrupted pulse-modulated waves and based upon the Doppler effect resulting from movement of targets
• CPC Class Codes: G01S 7/524 Transmitters
• CPC Class Codes: G01S 7/527 Extracting wanted echo signals Doppler systems G01S15/50

Abstract

Apparatus and methods for velocity scanning in, e.g., bodies of water. In one embodiment, a scanned one-dimensional transducer array Doppler sonar arrangement is used to remotely measure both vertical and horizontal profiles of a river or channel along-stream water velocities within a cross-section of the river/channel from a single side-mounted sonar.

Claims

1. An acoustic system, comprising:

one or more discrete one-dimensional arrays, each discrete one-dimensional array consisting essentially of multiple substantially parallel first-axis rows of transducer elements, the transducer elements configured to be mounted at a location in a fluid flow channel, and to be oriented so as to ensonify across a direction of flow in the channel, the transducer elements each having an elongated dimension on an elongated axis along a face of the transducer that is longer in dimension as compared with a length dimension on the face of the transducer that is perpendicular to the elongated axis, the elongated axis on the face of one of the transducer elements being parallel with other elongated axes of other ones of the transducer elements such that the elongated axes are not collinear with one another; and

a beamformer circuit electrically connected to the transducer elements in the first-axis rows of the array, the beamformer circuit configured to delay signals associated respectively with each first-axis row.

2. The system of claim 1, wherein the orientation comprises an angular component in the first-axis and a second-axis substantially orthogonal thereto, and further comprising a prescribed angle in a third-axis which is substantially orthogonal to the first-axis and second-axis.

3. The system of claim 2, wherein the first-axis and the second-axis are substantially parallel to a plane containing a surface of the fluid flow channel, and the third-axis comprises a substantially vertical axis.

4. The system of claim 1, wherein the system is configured to sequentially and/or simultaneously form one or more sets of transmit and/or receive beam sets projected into the channel flow stream, the one or more sets each comprising an angular dispersion at least within a plane oriented substantially perpendicular to a surface of the flow channel.

5. The system of claim 1, wherein the system is configured to generate both transmit and receive beam sets, the sets each oriented with different angular components in the first-axis and a second-axis substantially orthogonal thereto, across the direction of flow in the channel.

6. The system of claim 1, where the rows are arranged substantially in a plane of rectangular, circular, elliptical or polygonal shape.

7. The system of claim 1, wherein:

the orientation comprises an angular component in the first-axis and a second-axis substantially orthogonal thereto, and further comprising a prescribed angle in a third-axis which is substantially orthogonal to the first-axis and second-axis, the first-axis and the second-axis being substantially parallel to a plane containing a surface of the fluid flow channel, and the third-axis comprising a substantially vertical axis; and

the system is configured to sequentially and/or simultaneously form one or more sets of transmit and/or receive beam sets projected into the channel flow stream, the one or more sets each comprising an angular dispersion at least within a plane oriented substantially perpendicular to a surface of the flow channel.

8. The system of claim 1, where the system is configured to transmit a signal comprising a pulse.

9. The system of claim 8, where the pulsed transmitted signal comprises a broadband coded pulse.

10. The system of claim 1, further comprising at least one solid disc piston-type vertically-oriented transducer configured to create a conical upward looking beam to be used to measure a height of a surface of the fluid flow channel above the transducer.

11. An acoustic system, comprising:

one or more discrete one-dimensional array transducers, each discrete one-dimensional array transducer consisting essentially of multiple substantially parallel rows of transducer elements associated with a first axis, each of the transducer elements having an elongated axis that is parallel, yet not collinear with, other ones of the transducer element elongated axes, the transducers configured to be mounted at a fixed location in a fluid flow channel, and oriented with an angular component in the first axis and a second axis substantially orthogonal thereto, and substantially across a direction of flow in the channel, and with an angle in a third axis substantially orthogonal to the first and second axes;

a transmit/receive switch;

a transmit beamformer circuit electrically connected via the transmit/receive switch to the elements in the rows, wherein the transmit beamformer circuit is configured to delay signals associated, respectively, with each row; and

a receive beamformer circuit electrically connected via the transmit/receive switch to the elements in the rows, wherein the receive beamformer circuit delays signals associated, respectively, with each row;

wherein the system is configured to;

set the transmit/receive switch to a transmit setting, and sequentially and/or simultaneously form one or more transmit beams projected into the fluid flow channel; and

set the transmit/receive switch to a receive setting, and sequentially and/or simultaneously form one or more receive beams projected into the fluid flow channel.

12. A method of determining fluid flow in a channel, comprising:

providing at least one one-dimensional transducer array, the at least one array consisting essentially of multiple substantially parallel X-axis rows of transducer elements arranged in a single column, each of the transducer elements being elongated along the X-axis, the rows spaced at a prescribed spacing, the at least one array disposed at a fixed location within the channel so as transversely ensonify at least a portion of the channel; and

utilizing a beamformer circuit electrically connected to the transducer elements in the X-axis rows of the at least one array, applying fixed phase-delayed signals associated, respectively between the X-axis rows;

wherein an angle of a beam in a Z-axis, the beam formed by the utilizing, is determined at least in part by phase shifts associated with the beamformer circuit phase-delayed signals.

13. The method of claim 12, further comprising sequentially changing the phase shifts so as to sequentially scan the beam in angular increments within an angular sector in the Z-axis.

14. The method of claim 13, further comprising forming multiple beams simultaneously within the sector by at least using multiple phase-shift beamformer circuits operating in parallel.

15. The method of claim 12, further comprising forming multiple beams simultaneously within an angular Z-axis sector by at least using multiple phase-shift beamformer circuits operating in parallel.

16. The method of claim 12, wherein the prescribed spacing comprises approximately one-half (½

) wavelength at a carrier operating frequency and sound speed associated with a relevant fluid media of the channel, and the angular sector comprises a sector of +/−

50 degrees relative to a vector substantially parallel to a surface of the fluid flow channel.

17. An apparatus configured to measure a fluid flow channel, the apparatus comprising:

at least one discrete one-dimensional transducer array comprising N substantially parallel rows of transducer elements disposed relative to a first axis and arranged in a single column of transducer elements, the at least one discrete one-dimensional transducer array to be mounted at a fixed location relative to the fluid flow channel, and oriented with an angular component in both the first axis and a second axis perpendicular to the first and across a direction of flow in the channel, each of the transducer elements having an elongated dimension along a face of the transducer element that is parallel with the first axis and a dimension along the face of the transducer element that is less than the elongated dimension, the dimension being parallel with the second axis;

a transmit/receive beamformer electrically interfaced to the N rows of the at least one transducer array;

a transmit/receive switch;

first logic configured to operate the transmit/receive beamformer in a transmit mode, wherein the transmit/receive beamformer generates a set of N electrical signals, each signal being time- or phase-delayed relative to each other, and wherein the transmit/receive beamformer applies each electrical signal to its respective transducer row, the resulting time- or phase-delayed signals from each row being combined together to sequentially and/or simultaneously form one or more transmit beams projected into the fluid flow channel; and

second logic configured to operate the transmit/receive beamformer in a receive mode, wherein the transmit/receive beamformer receives a set of N electrical signals, each signal being time- or phase-delayed, and wherein the transmit/receive beamformer applies each electrical signal to its respective transducer row, the resulting time- or phase-delayed signals from each row being combined together to sequentially and/or simultaneously form one or more receive beams projected into the fluid flow channel.

18. The apparatus of claim 17, wherein the apparatus is Doppler-based, and further comprises logic configured to process amplitude and Doppler frequency shifted echoes received from the fluid flow channel and a surface thereof at multiple time intervals, the intervals being on order of a transmit pulse width, so as to perform at least one of the following:

1) compute a Doppler frequency shift and velocity profile along a direction of the acoustic beams;

2) detect a slant range along each beam intersecting a bottom of the channel and the surface so as to compute a channel fluid depth at each slant range within a plurality of beams formed in an axis perpendicular to the surface;

3) combines a velocity profile and one or more depth measurements to compute a velocity flow field and discharge within a region ensonified by the plurality of beams; and

/or

4) computes a total channel discharge using measured data and an extrapolation algorithm.

19. The apparatus of claim 17, further configured to generate two or more of both transmit and receive beam sets oriented with different angular components relative to a plane formed by the first and second axes, across a direction of flow in the channel.

20. The apparatus of claim 17, wherein the one or more transmit beams comprises a single tone pulse, and a Doppler frequency is computed using a complex auto-correlation method at a time delay which is a fraction of a pulse width of the pulse.

21. The apparatus of claim 17, wherein the one or more transmit beams comprises a dual phase or frequency coded pulse, and the Doppler frequency is computed using a complex auto-correlation method at a time delay approximately equal to a dual-pulse lag.

22. The apparatus of claim 17, wherein the one or more transmit beams comprises either a single tone or dual phase or frequency coded pulse, and a Doppler Frequency is computed using a complex auto-correlation method at a time delay equal to the time lag between successive pulse transmissions.