Meter Electronics And Methods For Rapidly Determining A Mass Fraction Of A Multi-Phase Fluid From A Coriolis Flow Meter Signal

• US 20080184815A1
• Filed: 05/19/2006
• Published: 08/07/2008
• Est. Priority Date: 05/20/2005
• Status: Active Grant

• Current Assignee: Micro Motion Incorporated (Emerson Electric Company)
• Original Assignee: Micro Motion Incorporated (Emerson Electric Company)
• Inventors: McAnally, Craig B., Bell, Mark James
• Granted Patent: US 7,805,261 B2
• Time in Patent Office: Days
• US Class Current: 73/861.356
• CPC Class Codes: G01F 1/74 Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid
• CPC Class Codes: G01F 1/8413 means for influencing the flowmeter's motional or vibrational behaviour, e.g., conduit support or fixing means, or conduit attachments
• CPC Class Codes: G01F 1/8436 signal processing
• CPC Class Codes: G01F 1/8477 with multiple measuring conduits
• CPC Class Codes: G01F 15/024 involving digital counting

Abstract

Meter electronics (20) for determining a mass fraction of flow components in a flow material flowing is provided according to an embodiment of the invention. The meter electronics (20) include an interface (201) for receiving a frequency response of the flow material and a processing system (203). The processing system (203) receives the frequency response from the interface (201) and breaks out the frequency response into at least a gas frequency component and a fluid frequency component. The processing system (203) determines an overall density from the frequency response and determines a gas density from the gas frequency component. The processing system (203) determines the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component. The processing system (203) determines the mass fraction from the void fraction of gas multiplied by a ratio of the gas density divided by the overall density.

Claims

1. Meter electronics (20) for determining a mass fraction of flow components in a flow material flowing through a flow meter (5), the meter electronics (20) comprising:

an interface (201) for receiving a frequency response of the flow material; and

a processing system (203) in communication with the interface (201) and configured to receive the frequency response from the interface (201), break out the frequency response into at least a gas frequency component and a fluid frequency component, determine an overall density from the frequency response, determine a gas density from the gas frequency component, determine the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component, and determine the mass fraction from the void fraction of gas multiplied by a ratio of the gas density divided by the overall density.

2. The meter electronics (20) of claim 1, with the gas density comprising an inverse of the gas frequency squared and with the overall density comprising an inverse of the frequency squared.

3. The meter electronics (20) of claim 1, with the processing system (203) being further configured to determine a mass flow rate of the flow material from the frequency response and determine at least one of a first flow component mass and a second flow component mass using the mass fraction and the mass flow rate.

4. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to determine a substantially instantaneous frequency and determine a substantially instantaneous phase difference, wherein the mass flow rate is determined using the frequency and the phase difference.

5. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to determine a substantially instantaneous frequency, determine a substantially instantaneous phase difference, divide the phase difference by the frequency in order to obtain a time delay, and multiply the time delay by a constant in order to obtain the mass flow rate.

6. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to generate a first 90 degree phase shift from the first sensor signal, compute the frequency using the first 90 degree phase shift and the first sensor signal, determine a substantially instantaneous phase difference, divide the phase difference by the frequency in order to obtain a time delay, and multiply the time delay by a constant in order to obtain the mass flow rate.

7. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to generating a first 90 degree phase shift from the first sensor signal, computing the phase difference using the first 90 degree phase shift, the first sensor signal, and the second sensor signal, determining a substantially instantaneous phase difference, dividing the phase difference by the frequency in order to obtain a time delay, and multiplying the time delay by a constant in order to obtain the mass flow rate.

8. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to generating a first 90 degree phase shift from the first sensor signal, generating a second 90 degree phase shift from the second sensor signal, computing the phase difference using the first 90 degree phase shift, the second 90 degree phase shift, the first sensor signal, and the second sensor signal, determining a substantially instantaneous phase difference, dividing the phase difference by the frequency in order to obtain a time delay, and multiplying the time delay by a constant in order to obtain the mass flow rate.

9. The meter electronics (20) of claim 3, with the frequency response comprising a first sensor signal and a second sensor signal and with the processing system (203) being further configured to generate a 90 degree phase shift from the first sensor signal, compute a frequency response using the 90 degree phase shift and the first sensor signal, compute a phase difference using at least the 90 degree phase shift, the first sensor signal, and the second sensor signal, compute a time delay using the frequency response and the phase difference, compute the mass flow rate from the time delay, determine a substantially instantaneous phase difference, divide the phase difference by the frequency in order to obtain a time delay, and multiply the time delay by a constant in order to obtain the mass flow rate.

10. A method for determining a mass fraction of flow components in a flow material flowing through a flow meter, the method comprising:

receiving a frequency response of the flow material;

breaking out the frequency response into at least a gas frequency component and a fluid frequency component;

determining an overall density from the frequency response;

determining a gas density from the gas frequency component;

determining the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component; and

determining the mass fraction from the void fraction of gas multiplied by a ratio of the gas density divided by the overall density.

11. The method of claim 10, with the gas density comprising an inverse of the gas frequency squared and with the overall density comprising an inverse of the frequency squared.

12. The method of claim 10, further comprising:

determining a mass flow rate of the flow material from the frequency response; and

determining at least one of a first flow component mass and a second flow component mass using the mass fraction and the mass flow rate.

13. The method of claim 12, with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency; and

determining a substantially instantaneous phase difference, wherein the mass flow rate is determined using the frequency and the phase difference.

14. The method of claim 12, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

15. The method of claim 12, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the frequency using the first 90 degree phase shift and the first sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

16. The method of claim 12, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the phase difference using the first 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

17. The method of claim 12, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

generating a second 90 degree phase shift from the second sensor signal;

computing the phase difference using the first 90 degree phase shift, the second 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

18. The method of claim 12, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a 90 degree phase shift from the first sensor signal;

computing a frequency response using the 90 degree phase shift and the first sensor signal;

computing a phase difference using at least the 90 degree phase shift, the first sensor signal, and the second sensor signal;

computing a time delay using the frequency response and the phase difference;

computing the mass flow rate from the time delay;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

19. A method for determining a mass fraction of flow components in a flow material flowing through a flow meter, the method comprising:

receiving a frequency response of the flow material;

processing the frequency response with a notch filter that substantially rejects one of a gas frequency component and a fluid frequency component;

determining an overall density from the frequency response;

determining a gas density from the gas frequency component;

determining the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component; and

determining the mass fraction from the void fraction of gas multiplied by a ratio of the gas density divided by the overall density.

20. The method of claim 19, with the gas density comprising an inverse of the gas frequency squared and with the overall density comprising an inverse of the frequency squared.

21. The method of claim 19, further comprising:

determining a mass flow rate of the flow material from the frequency response; and

determining at least one of a first flow component mass and a second flow component mass using the mass fraction and the mass flow rate.

22. The method of claim 21, with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency; and

determining a substantially instantaneous phase difference, wherein the mass flow rate is determined using the frequency and the phase difference.

23. The method of claim 21, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

24. The method of claim 21, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the frequency using the first 90 degree phase shift and the first sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

25. The method of claim 21, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the phase difference using the first 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

26. The method of claim 21, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

generating a second 90 degree phase shift from the second sensor signal;

computing the phase difference using the first 90 degree phase shift, the second 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

27. The method of claim 21, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a 90 degree phase shift from the first sensor signal;

computing a frequency response using the 90 degree phase shift and the first sensor signal;

computing a phase difference using at least the 90 degree phase shift, the first sensor signal, and the second sensor signal;

computing a time delay using the frequency response and the phase difference;

computing the mass flow rate from the time delay;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

28. A method for determining a mass fraction of flow components in a flow material flowing through a flow meter, the method comprising:

receiving a frequency response of the flow material;

filtering the frequency response with a first filter that substantially rejects the gas frequency component and substantially passes the fluid frequency component, wherein the first filter outputs the fluid frequency component;

filtering the frequency response with a second filter that substantially rejects the fluid frequency component and substantially passes the gas frequency component, wherein the second filter outputs the gas frequency component;

determining an overall density from the frequency response;

determining a gas density from the gas frequency component;

determining the void fraction of gas from the frequency response and one or more of the gas frequency component and the fluid frequency component; and

determining the mass fraction from the void fraction of gas multiplied by a ratio of the gas density divided by the overall density.

29. The method of claim 28, with the gas density comprising an inverse of the gas frequency squared and with the overall density comprising an inverse of the frequency squared.

30. The method of claim 28, further comprising:

determining a mass flow rate of the flow material from the frequency response; and

determining at least one of a first flow component mass and a second flow component mass using the mass fraction and the mass flow rate.

31. The method of claim 30, with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency; and

determining a substantially instantaneous phase difference, wherein the mass flow rate is determined using the frequency and the phase difference.

32. The method of claim 30, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate comprising:

determining a substantially instantaneous frequency;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

33. The method of claim 30, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the frequency using the first 90 degree phase shift and the first sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

34. The method of claim 30, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

computing the phase difference using the first 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

35. The method of claim 30, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a first 90 degree phase shift from the first sensor signal;

generating a second 90 degree phase shift from the second sensor signal;

computing the phase difference using the first 90 degree phase shift, the second 90 degree phase shift, the first sensor signal, and the second sensor signal;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.

36. The method of claim 30, with the frequency response comprising a first sensor signal and a second sensor signal and with the determining the mass flow rate further comprising:

generating a 90 degree phase shift from the first sensor signal;

computing a frequency response using the 90 degree phase shift and the first sensor signal;

computing a phase difference using at least the 90 degree phase shift, the first sensor signal, and the second sensor signal;

computing a time delay using the frequency response and the phase difference;

computing the mass flow rate from the time delay;

determining a substantially instantaneous phase difference;

dividing the phase difference by the frequency in order to obtain a time delay; and

multiplying the time delay by a constant in order to obtain the mass flow rate.