Vibratory flowmeter friction compensation

Patent metadata

Field	Value
Publication number	US-9689735-B2
Application number	US-200913509870-A
Country	US
Kind code	B2
Filing date	Dec 1, 2009
Priority date	Dec 1, 2009
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

The invention relates to meter electronics ( 20 ) for vibratory flowmeter friction compensation is provided. The meter electronics ( 20 ) includes an interface ( 201 ) configured to communicate with a flowmeter assembly ( 10 ) of a vibratory flowmeter ( 5 ) and receive a vibrational response and a processing system ( 203 ) coupled to the interface ( 201 ) and configured to measure a mass flow rate of a fluid using the vibrational response. The processing system ( 203 ) is configured to determine a fluid velocity (V) using the mass flow rate, a fluid density (p), and a cross-sectional flow area (A), determine a friction factor (f) using the fluid velocity (V) and a pressure drop (ΔP), and determine a compensation factor using the friction factor (f). The invention also relates to a vibratory flowmeter compensation method.

First claim

What is claimed is:

1. A flowmeter for vibratory flowmeter friction compensation, comprising:
an unrestricted flow tube configured to receive a process fluid therein;
a driver in communication with the unrestricted flow tube configured to generate a vibratory signal through the unrestricted flow tube;
at least one pickoff sensor with the unrestricted flow tube configured to detect a vibratory signal of the driver and generate a vibrational response;
meter electronics comprising a portion of the vibratory flowmeter, being configured to receive the vibrational response and having a processing system coupled to an interface configured to communicate with the vibratory flowmeter and further configured to measure a mass flow rate ({dot over (m)}) of a fluid in the unrestricted flow tube using the vibrational response, with the processing system being characterized by:
the processing system being configured to determine a fluid velocity (V) using the mass flow rate ({dot over (m)}), a fluid density (ρ), and a cross-sectional flow area (A), determine a friction factor (f) using the fluid velocity (V), density (ρ), and a pressure drop (ΔP), and determine a compensation factor using the friction factor (f); and

a pressure sensor in communication with the vibratory flowmeter configured to measure the pressure drop (ΔP) wherein the pressure sensor is separate from the at least one pickoff sensor;
wherein the processing system is further configured to generate a friction-compensated mass flow rate ({dot over (m)} comp ) from the compensation factor.

2. The flowmeter of claim 1 , further comprising the meter electronics receiving the fluid density (ρ).

3. The flowmeter of claim 1 , further comprising the vibratory flowmeter measuring the fluid density (ρ).

4. The flowmeter of claim 1 , further comprising the meter electronics receiving the pressure drop (ΔP).

5. The flowmeter of claim 1 , with the processing system being further configured to generate a friction-compensated volume flow rate ({dot over (v)} comp ).

6. The flowmeter of claim 1 , with determining the compensation factor comprising correlating the friction factor (f) to empirically-derived data.

7. A vibratory flowmeter friction compensation method, the method comprising:
providing a vibratory flowmeter having meter electronics having a processing system coupled to an interface configured to communicate with the vibratory flowmeter;
providing a unrestricted flow tube configured to receive a process fluid therein;
providing a driver in communication with the unrestricted flow tube configured to generate a vibratory signal through the unrestricted flow tube;
providing at least one pickoff sensor with the unrestricted flow tube configured to detect a vibratory signal of the driver and generate a vibrational response;
measuring a mass flow rate ({dot over (m)}) of a fluid in the unrestricted flow tube using the vibratory flowmeter, with the method being characterized by:
determining a fluid velocity (V) using the mass flow rate ({dot over (m)}), a fluid density (ρ), and a cross-sectional flow area (A);
determining a friction factor (f) using the fluid velocity (V) , density (ρ), and a pressure drop (ΔP);

determining a compensation factor using the friction factor (f);
providing a pressure sensor in communication with the meter electronics, wherein the pressure sensor is separate from the at least one pickoff sensor;
measuring a pressure drop (ΔP) with the pressure sensor; and
generating a friction-compensated mass flow rate ({dot over (m)} comp ) from the compensation factor.

8. The method of claim 7 , further comprising a meter electronics of the vibratory flowmeter receiving the fluid density (ρ).

9. The method of claim 7 , further comprising the vibratory flowmeter measuring the fluid density (ρ).

10. The method of claim 7 , further comprising a meter electronics of the vibratory flowmeter.

11. The method of claim 7 , further comprising generating a friction-compensated volume flow rate ({dot over (V)} comp ).

12. The method of claim 7 , with determining the compensation factor comprising correlating the friction factor (f) to empirically-derived data.

13. A vibratory flowmeter friction compensation method, the method comprising:
providing a vibratory flowmeter having at least one pickoff sensor and meter electronics having a processing system coupled to an interface configured to communicate with the vibratory flowmeter;
measuring a mass flow rate ({dot over (m)}) of a fluid in a unrestricted flow tube of the vibratory flowmeter using the vibratory flowmeter and measuring a fluid density (ρ) using the vibratory flowmeter, with the method being characterized by:
determining a fluid velocity (V) using the mass flow rate ({dot over (m)}), the fluid density (ρ), and a cross-sectional flow area (A);
determining a friction factor (f) using the fluid velocity (V) , density (ρ), and a pressure drop (ΔP); and

determining a compensation factor using the friction factor (f);
providing a pressure sensor in communication with the meter electronics wherein the pressure sensor is separate from the at least one pickoff sensor;
measuring a pressure drop (ΔP) with the pressure sensor; and
generating a friction-compensated mass flow rate ({dot over (m)} comp ) from the compensation factor.

14. The method of claim 13 , wherein the meter electronics of the vibratory flowmeter is configured to receive the pressure drop (ΔP).

15. The method of claim 13 , further comprising generating a friction-compensated volume flow rate ({dot over (v)} comp ) .

16. The method of claim 13 , with determining the compensation factor comprising correlating the friction factor (f) to empirically-derived data.

Assignees

• Pankratz Anthony William
• Weinstein Joel
• Micro Motion Inc

Inventors

• Pankratz Anthony William
• Weinstein Joel

Classifications

• G01F1/8436 Primary

  signal processing · CPC title

• G01F25/0007 Primary

  Physics · mapped topic

• G01F1/8477

  with multiple measuring conduits · CPC title

• G01F25/10 Primary

  of flowmeters · CPC title