Flow measurement by combining 3L echo with delta time-of-flight cross correlation

Patent metadata

Field	Value
Publication number	US-11906338-B2
Application number	US-202117188645-A
Country	US
Kind code	B2
Filing date	Mar 1, 2021
Priority date	Jun 5, 2020
Publication date	Feb 20, 2024
Grant date	Feb 20, 2024

Abstract

Methods and systems for flow measurement can involve calculating an absolute-time-of-flight with respect to a flow of a fluid in a flow channel by reflected signals, reflected and unreflected signals, or a pulse train, determining a delta-time-of-flight with a cross correlation of two signals with respect to the flow of the fluid in the flow channel, and calculating the flow rate of the flow of the fluid in the flow channel based on the absolute-time-of-flight and the cross correlation of the delta-time-of-flight.

First claim

What is claimed is:

1. A method for flow measurement in a flow channel associated with a first transducer and a second transducer, the method, comprising:
calculating an absolute-time-of-flight with respect to a flow of a fluid in the flow channel by reflected signals, reflected and unreflected signals, or a pulse train;
determining a delta-time-of-flight with a cross correlation of two signals with respect to the flow of the fluid in the flow channel; and
calculating a flow rate of the flow of the fluid in the flow channel based on the absolute-time-of-flight and the delta-time-of-flight, wherein calculating the flow rate of the flow of the fluid in the flow channel comprises measuring the absolute-time-of-flight of 3×length between the first transducer and the second transducer and subtracting the absolute-time-of-flight of 1×length between the first transducer and the second transducer, to eliminate electrical and acoustic delays and wherein measuring the absolute-time-of-flight of 3L between the first transducer and the second transducer includes dividing 2×length (2L) between the first transducer and the second transducer by a first term ‘c+v’, and dividing 1×length between the first transducer and the second transducer by a second term ‘c−v’, and wherein the first term and the second term are based on a speed of sound and a medium velocity of the fluid in the flow channel.

2. The method of claim 1 wherein calculating the flow rate of the flow of the fluid based on the absolute-time-of-flight and the cross correlation of the delta-time-of-flight, further comprises:
calculating the flow rate of the flow of the fluid based on the absolute-time-of-flight measured upstream and downstream in the flow channel, and the delta-time-of-flight.

3. The method of claim 2 wherein the absolute-time-of-flight measured upstream and the absolute-time-of-flight measured downstream are used to calculate the delta-time-of-flight and/or the flow rate.

4. The method of claim 2 wherein different acoustic paths comprise different input signals with different gains or output signals with different gains.

5. The method of claim 1 wherein calculating the absolute-time-of-flight with respect to the flow of the fluid in the flow channel by reflected signals, reflected signals, reflected and unreflected signals, or the pulse train, further comprises:
measuring the absolute-time-of-flight with respect to the flow of the fluid in the flow channel across a first acoustic path of the flow channel from the first transducer to the second transducer to determine a first absolute-time-of-flight; and
measuring the absolute-time-of-flight with respect to the flow of the fluid in the flow channel across a second acoustic path of the flow channel from the first transducer to the second transducer to determine a second absolute-time-of-flight, and calculating a third absolute-time-of-flight by the difference between the first absolute-time-of-flight and the second absolute-time-of-flight.

6. The method of claim 5 wherein:
an acoustic path including the first acoustic path or the second acoustic path comprises reflected or reflected and unreflected signals between the first transducer and the second transducer.

7. The method of claim 1 wherein the reflected signals, the reflected and unreflected signals or the pulse train comprise at least one of: ultrasound; acoustic sound; or light.

8. The method of claim 7 wherein the absolute-time-of-flight is used to calculate the speed of sound by dividing a length of the acoustic path with the absolute-time-of-flight.

9. The method of claim 1 wherein the flow channel is associated with a gas meter comprising an ultrasonic gas meter.

10. A system for flow measurement, comprising:
a gas meter having a first transducer, a second transducer, and a flow channel between the first transducer and the second transducer, wherein:
an absolute-time-of-flight with respect to a flow of a fluid in the flow channel is calculated by reflected signals, reflected and unreflected signals, or a pulse train;
a delta-time-of-flight with respect to the flow of the fluid in the flow channel is determined with a cross correlation of two signals; and
a flow rate of the flow of the fluid in the flow channel is calculated based on the absolute-time-of-flight and the delta time-of-flight, wherein calculating the flow rate of the flow of the fluid in the flow channel comprises measuring the absolute-time-of flight of 3×length between the first transducer and the second transducer and subtracting the absolute-time-of-flight of 1×length between the first transducer and the second transducer, to eliminate the electrical and acoustic delays and wherein measuring the absolute-time-of-flight of 3L between the first transducer and the second transducer includes dividing 2×length (2L) between the first transducer and the second transducer by a first term ‘c+v’, and dividing 1×length between the first transducer and the second transducer by a second term ‘c−v’, and wherein the first term and the second term are based on a speed of sound and a medium velocity of the fluid in the flow channel.

11. The system of claim 10 wherein the flow rate of the flow of the fluid is calculated based on the absolute-time-of-flight measured upstream and downstream in the flow channel, and the delta-time-of-flight.

12. The system of claim 11 wherein the absolute-time-of-flight measured upstream and the absolute-time-of-flight measured downstream are used to calculate the delta-time-of-flight and/or the flow rate.

13. The system of claim 11 wherein different acoustic paths comprise different input signals with different gains or output signals with different gains.

14. The system of claim 10 wherein:
the absolute-time-of-flight is measured with respect to the flow of the fluid in the flow channel across a first acoustic path of the flow channel from the first transducer to the second transducer to determine a first absolute-time-of-flight;
the absolute-time-of-flight with respect to the flow of the fluid in the flow channel is measured across a second acoustic path of the flow channel from the first transducer to the second transducer to determine a second absolute-time-of-flight and calculating a third absolute-time-of-flight by the difference between the first absolute-time-of-flight and the second absolute-time-of-flight.

15. The system of claim 14 wherein:
an acoustic path including the first acoustic path or the second acoustic path comprises reflected or reflected and unreflected signals between the first transducer and the second transducer.

16. The system of claim 10 wherein the reflected signals, the reflected and unreflected signals or the pulse train comprise at least one of: ultrasound; acoustic sound; or light.

17. The system of claim 16 wherein the absolute-time-of-flight is used to calculate the speed of sound by dividing a length of the acoustic path with the absolute-time-of-flight.

18. A system for flow measurement, comprising:
at least one processor; and
a non-transitory computer-usable medium embodying computer program code, said computer-usable medium capable of communicating with the at least one processor, the computer program code comprising instructions executable by the at least one processor and configured for:
calculating an absolute-time-of-flight with respect to a flow of a fluid in a flow channel by reflected signals, reflected and unreflected signals, or a pulse train;
determining a delta-time-of-flight with a cross correlation of two signals with respect to

Assignees

• Honeywell Int Inc

Inventors

• Meimberg Tobias
• Lampe-Jürgens Christian
• Schröder Genannt Berghegger Ralf Heinrich
• Wuchrer Andreas

Classifications

• G01F1/662 Primary

  Constructional details · CPC title

• G01F1/661

  using light · CPC title

• G01F1/666

  by detecting noise and sounds generated by the flowing fluid · CPC title

• G01F1/668 Primary

  Compensating or correcting for variations in velocity of sound · CPC title