US-20260126315-A1 - DETERMINING AND USING A MASS FLOW RATE ERROR CORRECTION RELATIONSHIP IN A VIBRATORY TYPE FLOW METER

US20260126315A1US 20260126315 A1US20260126315 A1US 20260126315A1US-20260126315-A1

Abstract

A method for determining a mass flow rate error correction relationship is provided. The method includes comparing each of the plurality of mass flow rate measurements of a substitute gas flow with a corresponding each of a plurality of reference mass flow rate measurements of the substitute gas flow. The method also includes determining, based on the comparisons, a plurality of mass flow rate measurement errors corresponding to a plurality of fluid velocity-related parameter values of the substitute gas flow.

Inventors

David KUHNY
Andrew Timothy Patten
Marc Allan Buttler

Assignees

MICRO MOTION, INC.

Dates

Publication Date: 20260507
Application Date: 20221111

Claims (19)

1 . A method of determining a mass flow rate error correction value for a vibratory meter, the method comprising: comparing each of a plurality of mass flow rate measurements of a substitute gas flow with a corresponding each of a plurality of reference mass flow rate measurements of the substitute gas flow; and determining, based on the comparisons, a plurality of mass flow rate measurement errors corresponding to a plurality of fluid velocity-related parameter values of the substitute gas flow.
2 . The method of claim 1 , wherein the plurality of fluid velocity-related parameter values of the substitute gas flow comprises one of a plurality of fluid velocity values and a plurality of Mach number values of the substitute gas flow.
3 . The method of claim 1 , wherein the plurality of reference mass flow rate measurements of the substitute gas flow is provided by a reference device in line with the vibratory meter.
4 . The method of claim 1 , wherein the substitute gas flow comprises one of air, natural gas, carbon dioxide, nitrogen, and helium.
5 . The method of claim 1 , wherein the plurality of mass flow rate measurement errors corresponding to the plurality of fluid velocity-related parameter values of the substitute gas flow comprises a plurality of differences between the each of the plurality of mass flow rate measurement values and the corresponding each of the plurality of reference mass flow rate measurement values.
6 . The method of claim 1 , further comprising flowing the substitute gas flow through the vibratory meter.
7 . The method of claim 1 , further comprising determining, with the vibratory meter, the plurality of mass flow rate measurements at the corresponding plurality of fluid velocity-related parameter values of the substitute gas flow.
8 . The method of claim 1 , further comprising storing the plurality of the mass flow rate measurement errors in a meter electronics of the vibratory meter as a plurality of ordered pairs of the plurality of the mass flow rate measurement errors and the corresponding plurality of the fluid velocity-related parameter values.
9 . The method of claim 1 , further comprising determining a mass flow rate error correction relationship based on the plurality of mass flow rate measurement errors and the corresponding plurality of fluid velocity-related parameter values and storing the mass flow rate error correction relationship in the vibratory meter.
10 . A system ( 1000 ) for determining a mass flow rate error correction relationship for a vibratory meter ( 5 ), the system ( 1000 ) comprising: the vibratory meter ( 5 ) configured to measure a mass flow rate of a substitute gas flow; a reference device ( 1010 ) in line with the vibratory meter ( 5 ), the reference device ( 1010 ) being configured to determine a reference mass flow rate of the substitute gas flow; and a calibration circuit ( 1020 ) in communication with the vibratory meter ( 5 ) and the reference device ( 1010 ), the calibration circuit ( 1020 ) being configured to perform the method of claim 1 .
11 . A method for using a mass flow rate error correction relationship for a vibratory meter, the method comprising: determining a fluid velocity-related parameter value of a process gas flow based on a measured mass flow rate value, a density value, and a cross-sectional area of the process gas flow; and determining a mass flow rate error correction value based on the fluid velocity-related parameter value.
12 . The method of claim 11 , wherein the fluid velocity-related parameter value comprises one of a fluid velocity value and a Mach number value of the process gas flow.
13 . The method of claim 11 , wherein the process gas flow is a hydrogen gas flow.
14 . The method of claim 11 , further comprising measuring, with the vibratory meter, a mass flow rate of the process gas flow to determine the measured mass flow rate value.
15 . The method of claim 11 , further comprising correcting the measured mass flow rate value with the mass flow rate error correction value.
16 . The method of claim 11 , wherein determining the mass flow rate error correction value based on the fluid velocity-related parameter value comprises: obtaining the mass flow rate error correction relationship for a substitute gas flow; and determining the mass flow rate correction value based on the mass flow rate error correction relationship for the substitute gas flow and the fluid velocity-related parameter value.
17 . The method of claim 16 , wherein the substitute gas flow comprises one of air, natural gas, carbon dioxide, nitrogen, and helium.
18 . A meter electronics ( 20 ) for using a mass flow rate error correction relationship, the meter electronics ( 20 ) comprising: a storage system ( 304 ); and a processing system ( 302 ) communicatively coupled to the storage system ( 304 ), the processing system ( 302 ) being configured to execute a method of claim 11 .
19 . A vibratory meter ( 5 ) for using a mass flow rate error correction relationship, the vibratory meter ( 5 ) comprising: a sensor assembly ( 10 ) configured to measure a mass flow rate of a process gas flow; and a meter electronics ( 20 ) communicatively coupled to the sensor assembly ( 10 ), the meter electronics ( 20 ) being provided according to the foregoing claim 18 .

Description

TECHNICAL FIELD The embodiments described below relate to correcting mass flow rate of a vibratory meter and, more particularly, to determining and using a mass flow rate error correction relationship for the vibratory meter. BACKGROUND Vibratory meters, such as for example, Coriolis mass flowmeters, liquid density meters, gas density meters, liquid viscosity meters, gas/liquid specific gravity meters, gas/liquid relative density meters, and gas molecular weight meters, are generally known and are used for measuring properties of fluids. Generally, vibratory meters comprise a sensor assembly and a meter electronics. The material within or about the sensor assembly may be flowing or stationary. The vibratory meter may be used to measure a mass flow rate, density, or other properties of a material in the sensor assembly. For example, Coriolis flow meters can measure a mass flow rate. By way of illustration the Coriolis flow meter may provide a drive signal to a driver that is disposed between two parallel and balanced conduits containing a fluid flowing through the conduits. The driver induces an out of phase vibration between the two conduits. The fluid flowing through the two conduits induces a phase difference of the inlets and outlets of the two conduits. This phase difference is measured by two pickoff sensors that are positioned on either side of a midpoint of the two conduits. For example, one pickoff may be proximate the inlets of the two conduits and another of the two pickoffs may be proximate the outlets of the two conduits. The measured phase difference is scaled by a flow calibration factor to obtain a mass flow rate measurement value. When gas is measured, the mass flow rate measurement value typically includes an error, which may be referred to as a mass flow rate measurement error, that is correlated with a mass flow rate of the gas. Accordingly, calibration of Coriolis flow meters intended for measuring gas flows typically include determining mass flow rate measurement errors on a mass flow rate basis. For example, a reference Coriolis flow meter in line with a Coriolis flow meter being calibrated may provide a known mass flow rate measurement value of the gas flow. The known mass flow rate measurement value of the gas flow may be compared to an uncorrected mass flow rate measurement provided by the Coriolis flow meter being calibrated to determine a mass flow rate measurement error. This comparison to determine the mass flow rate measurement error may be performed at various mass flow rates of the gas flow to obtain pairs (e.g., ordered pairs) of mass flow rate measurement error values and mass flow rate values. The pairs may be used to correct a subsequent uncorrected mass flow rate measurement value obtained by the Coriolis flow meter. As can be appreciated, a process gas may not be available for calibrating the Coriolis flow meter. Accordingly, substitute gases have been used to calibrate Coriolis flow meters. The substitute gases typically have densities that are different than a density of the process gas. This difference in density can cause deviations between mass flow rate measurement errors between different gases at a given flow rate. To reduce the density effects on mass flow rate measurement errors, a pressure of the substitute gas is adjusted until a density of the substitute gas is about the same as a density of the process gas whose mass flow rate measurement values are to be corrected. However, a property or properties other than density can cause deviations between a mass flow rate measurement error of the substitute gas flow and the process gas flow. As a result, if the deviations are significant enough, the mass flow rate measurement errors of a substitute gas flow may not necessarily be transferrable to correct mass flow rate measurement errors of a process gas flow. Accordingly, there is a need for determining and using a mass flow rate error correction relationship for a vibratory meter. SUMMARY A method of determining a mass flow rate error correction value for a vibratory meter is provided. According to an embodiment, the method comprises comparing each of a plurality of mass flow rate measurements of a substitute gas flow with a corresponding each of a plurality of reference mass flow rate measurements of the substitute gas flow, and determining, based on the comparisons, a plurality of mass flow rate measurement errors corresponding to a plurality of fluid velocity-related parameter values of the substitute gas flow. A system for determining a mass flow rate error correction relationship for a vibratory meter is provided. According to an embodiment, the system comprises the vibratory meter configured to measure a mass flow rate of a substitute gas flow, a reference device in line with the vibratory meter, the reference device being configured to determine a reference mass flow rate of the substitute gas flow, and a calibration circuit in communication with the vibra