Methods and Systems for Interpreting Multiphase Fluid Flow in A Conduit
Systems and methods are disclosed for interpreting measurements by a meter of defined dimension in a multiphase flow in a conduit in a wellbore. The meter may be a spinner used to obtain measurements at locations in the flow. The measurements may be averaged across a defined dimension, and a measurement model generated. A parameter profile (e.g., velocity) can be generated by curve fitting to the model.
1 . A method for interpreting measurements by a meter of defined dimension in a multiphase flow in a conduit in a wellbore, comprising:
obtaining a measurement with the meter at each of a plurality of locations in the multiphase flow, each measurement representing an average of a flow parameter across a defined dimension of the meter;
generating a measurement model as a function of the defined dimension of the meter and the average of the flow parameter; and
generating a parameter profile of the flow parameter by fitting a curve to the measurement model.
2 . The method of claim 1 , wherein the average of the flow parameter across the defined dimension of the meter comprises an average of the measurements over a cross-sectional area of the meter.
3 . The method of claim 1 , wherein the average of the flow parameter across the defined dimension of the meter comprises an average of the measurements over a volume of the meter.
4 . The method of claim 1 , wherein the average of the flow parameter across the defined dimension of the meter comprises a mass weighted average of the measurements over a volume of the meter.
5 . The method of claim 1 , wherein the defined dimension of the meter excludes a dead portion of the meter through which fluid does not flow.
6 . The method of claim 1 , wherein the parameter profile comprises one of a velocity profile and a holdup profile.
7 . The method of claim 1 , further comprising iteratively adjusting the measurement model to align with the measurements.
8 . The method of claim 1 , wherein the parameter profile comprises a velocity profile; the method further comprising:
obtaining holdup measurements;
generating a holdup profile by fitting a curve to the holdup measurements; and
determining a volumetric flow rate as a function of the holdup profile and the velocity profile over the conduit.
9 . The method of claim 8 , further comprising calculating a sum of a product of phase holdups and at least one phase density.
10 . A method for interpreting measurements in a multiphase flow in a conduit in a wellbore, the method comprising:
measuring a flow parameter with a sensor that averages the flow parameter over a dimension of investigation to generate a dimension averaged flow parameter;
providing a sensor response model including the dimension averaged flow parameter;
developing a flow parameter profile using the sensor response model; and
calculating a flow rate using the flow parameter profile.
11 . The method according to claim 10 , wherein the sensor comprises a spinner; and wherein providing a sensor response model comprises averaging the flow parameter over a swept area of the spinner.
12 . The method according to claim 11 , wherein providing a sensor response model further comprises correcting for a cross-sectional area of a non-flow area of the spinner.
13 . The method according to claim 11 , wherein providing a sensor response model further comprises mass fraction averaging the flow parameter over the swept area of the spinner.
14 . The method according to claim 10 , wherein providing a sensor response model comprises averaging the flow parameter over a volume investigated by the sensor.
15 . The method according to claim 14 , wherein providing a sensor response model, further comprises correcting for a volume occupied by a stationary portion of the sensor.
16 . The method according to claim 10 , wherein providing a sensor response model comprises modifying the sensor response model by a geometrical weighting factor.
17 . The method according to claim 16 , wherein the geometrical weighting factor comprises an inverse law for the sensor.
18 . The method according to claim 10 , wherein the flow parameter is one of density, velocity and holdup.
19 . A system for interpreting measurements in a multiphase flow in a conduit in a wellbore, comprising:
a meter of defined dimension that obtains a measurement at a plurality of locations in the multiphase flow, each measurement representing an average of a flow parameter across the defined dimension of the meter; and
a controller that generates a measurement model as a function of the defined dimension of the meter and the average of the flow parameter and applies a curve-fitting algorithm to the measurement model to generate a curve-fitted measurement model and to produce a parameter profile of the flow parameter based on the curve-fitted measurement model.
20 . The system of claim 19 , wherein the meter comprises a spinner and the measurement model generated by the controller is based on one of an average velocity over a swept area of the spinner, a mass fraction average velocity over the swept area of the spinner, and an average velocity over a volume investigated by the spinner.
21 . The system of claim 20 , wherein the controller further corrects the average of the flow parameter for a portion of the meter through which the multi-phase flow does not pass.