Wet gas measurement
View Patent ↗A multi-phase process fluid is passed through a vibratable flowtube. Motion is induced in the vibratable flowtube. A first apparent property of the multi-phase process fluid based on the motion of the vibratable flowtube is determined, and an apparent intermediate value associated with the multi-phase process fluid based on the first apparent property is determined. A corrected intermediate value is determined based on a mapping between the intermediate value and the corrected intermediate value. A phase-specific property of a phase of the multi-phase process fluid is determined based on the corrected intermediate value.
1. A method of measuring a multi-phase fluid, the method comprising:
passing the multi-phase fluid through a flowtube; vibrating the flowtube; using sensors to sense motion of the flowtube, each sensor generating a signal indicative of the motion of a different portion of the flowtube;
determining, by a controller, an apparent mass flow rate of the multi-phase process fluid based on a phase difference between the signals from the sensors;
determining, by the controller, an apparent intermediate value associated with the multi-phase fluid using the apparent mass flow rate;
determining, by the controller, a corrected intermediate value based on a mapping between the apparent intermediate value and the corrected intermediate value; and
determining, by the controller, a phase-specific mass flow rate of a phase of the multi-phase fluid based on the corrected intermediate value.
2. The method of claim 1 , wherein the mapping comprises a neural network.
3. The method of claim 2 , further comprising:
determining that the apparent intermediate value is within a first defined region of values prior to determining the corrected intermediate value; and
determining that the corrected intermediate value is within a second defined region of values prior to determining the phase-specific mass flow rate.
4. The method of claim 1 , wherein the multi-phase fluid is a wet gas.
5. The method of claim 4 , wherein the multi-phase fluid includes a first phase and a second phase, the first phase includes a non-gas fluid, and the second phase includes a gas.
6. The method of claim 4 , wherein the multi-phase fluid includes a first phase including a first non-gas fluid, and a second phase including a second non-gas fluid, and a third phase including a gas.
7. The method of claim 1 , further comprising determining an apparent density of the multi-phase fluid based on the signals from the sensors.
8. The method of claim 7 , further comprising determining a phase-specific density of the multi-phase fluid.
9. The method of claim 1 further comprising receiving one or more measurements corresponding to an additional property of the fluid.
10. The method of claim 9 wherein the additional property of the multi-phase fluid includes one or more of a temperature of the multi-phase fluid, a pressure associated with the multi-phase fluid, and a watercut of the multi-phase fluid; and wherein determining an apparent intermediate value associated with the multi-phase fluid includes determining the intermediate value based on the apparent mass flow rate and the additional property.
11. The method of claim 1 , wherein determining an apparent intermediate value associated with the multi-phase fluid based on the mass flow rate includes determining a volume fraction associated with an amount of non-gas fluid in the multi-phase fluid and a volumetric flow rate of the multi-phase fluid.
12. The method of claim 1 , wherein determining an apparent intermediate value associated with the multi-phase fluid based on the apparent mass flow rate includes determining a first Froude number corresponding to a non-gas phase of the multi-phase fluid and a second Froude number corresponding to a gas phase of the multi-phase fluid.
13. The method of claim 1 , wherein determining a phase-specific mass flow rate of a phase of the multi-phase fluid comprises determining a mass flow rate of a non-gas phase of the multi-phase fluid.
14. A flowmeter comprising:
a flowtube for containing a multi-phase fluid;
a driver connected to the flowtube and configured to vibrate the flowtube;
a pair of sensors connected to the flowtube at different locations on the flowtube and configured to output sensor signals indicative of the flowtube motion at said locations; and
a controller configured to:
receive the sensor signals;
determine an apparent mass flow rate of the multi-phase fluid based on a phase difference between the sensor signals;
determine an apparent intermediate value associated with the multi-phase fluid based on the apparent mass flow rate;
determine a corrected intermediate value based on a mapping between the apparent intermediate value and the corrected intermediate value; and
determine a phase-specific mass flow rate of a phase of the multi-phase fluid based on the corrected intermediate value.
15. The flowmeter of claim 14 wherein the mapping is a neural network configured to determine an error in the intermediate value resulting from the presence of the multi-phase fluid.
16. The flowmeter of claim 14 , wherein the controller is further configured to:
determine that the apparent intermediate value is within a first defined region of values prior to determining the corrected intermediate value; and
determine that the corrected intermediate value is within a second defined region of values prior to determining the phase-specific mass flow rate of a phase of the multi-phase fluid.
17. The flowmeter of claim 14 , wherein the multi-phase fluid is a wet gas.
18. The flowmeter of claim 14 , wherein determining the apparent mass flow rate of the multi-phase fluid includes determining an apparent density of the multi-phase fluid.
19. The flowmeter of claim 14 , wherein determining an apparent intermediate value associated with the multi-phase fluid based on the first apparent property includes determining a first Froude number corresponding to a non-gas phase of the multi-phase fluid and a second Froude number corresponding to a gas phase of the multi-phase fluid.
20. A transmitter for a Coriolis flowmeter of the type having a flowtube for containing a multi-phase fluid, a driver connected to the flowtube and configured to vibrate the flowtube, and a pair of sensors connected to the flowtube at different locations on the flowtube and configured to output sensor signals indicative of the flowtube motion at said locations, the transmitter comprising:
a controller configured to:
receive the sensor signals;
determine an apparent mass flow rate of the multi-phase fluid based on a phase difference between the sensor signals;
determine an apparent intermediate value associated with the multi-phase fluid based on the apparent mass flow rate;
determine a corrected intermediate value based on a mapping between the apparent intermediate value and the corrected intermediate value; and
determine a phase-specific mass flow rate of a phase of the multi-phase fluid based on the corrected intermediate value.