HK1152984A

HK1152984A - A system and method for detecting a process disturbance in a vibrating flow device

Info

Publication number: HK1152984A
Application number: HK11106906.7A
Authority: HK
Inventors: Charles Paul Stack; Joel Weinstein
Original assignee: Micro Motion, Inc.
Filing date: 2008-02-11
Publication date: 2012-03-16

Description

System, method for detecting process disturbances within a vibrating flow device

Technical Field

The present invention relates to systems, methods, and computer program products for detecting a process disturbance from entrained gas or particulate matter within a fluid flowing in a vibrating flow device.

Background

Vibrating flow devices such as densitometers and Coriolis flow meters are used to measure characteristics of a flow material such as density, mass flow rate, volumetric flow rate, total mass flow, temperature, and other information. The vibrating flow device includes one or more conduits, which may have various shapes, such as a straight line, a U-shape, or an irregular configuration.

One or more conduits have a set of natural vibration modes including, for example, simple bending, torsional, radial, and coupled vibration modes. One or more conduits are vibrated at one of these vibration modes at a resonant frequency by at least one driver in order to determine a characteristic of the flowing substance. One or more electronic devices transmit a sinusoidal drive signal to at least one driver, which is typically a magnet/coil combination, where the magnet is typically secured to an electrical circuit and the coil is secured to a support structure or another electrical circuit. The drive signal causes the driver to vibrate the one or more conduits at a drive frequency in a drive mode. For example, the drive signal may be a periodic current delivered to the coil.

At least one pick-off senses motion of the conduit and generates a pick-off signal indicative of motion of the one or more vibrating conduits. The sensor signal is transmitted to one or more electronic devices; and the sensor signal may be used by one or more electronic devices to determine the characteristics of the flowing substance or to adjust the drive signal if necessary, according to well-known principles.

One problem that may arise in the data output from a vibrating flow device is false readings resulting from sudden changes in material. In particular, if the flowing substance is a liquid and there are particles and/or bubbles in the liquid, this may cause large and inaccurate vibrations in the output.

The present invention aims to overcome this disadvantage inherent in existing vibrating flow devices.

Disclosure of Invention

The scope of protection of the invention is only determined by the appended claims and is not affected to any extent by what is stated in the summary of the invention.

In one embodiment of the present invention, a method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device comprises the steps of: the method further includes measuring the drive gain, determining a void fraction, and detecting the presence of the process disturbance based on a comparison between the measured drive gain and a drive gain threshold and a comparison between the void fraction and a void fraction threshold.

In another embodiment of the present invention, a method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device comprises the steps of: the method further includes measuring a drive gain, measuring a pickoff amplitude, and detecting the presence of the process disturbance based on a comparison between the measured drive gain and a drive gain threshold and a comparison between the measured pickoff amplitude and a pickoff amplitude threshold.

In yet another embodiment of the present invention, a computer program product comprises a computer usable medium having executable code embodied therein for performing a process for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device, the process comprising: the presence of the process disturbance is detected based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the void fraction and the void fraction threshold.

In yet another embodiment of the present invention, a computer program product comprises a computer usable medium having executable code embodied therein for performing a process for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device, the process comprising: the presence of the process disturbance is detected based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the measured pickoff amplitude and the pickoff amplitude threshold.

In a further embodiment of the present invention, a system for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device includes at least one conduit, at least one driver, at least one sensing element, and one or more electronics. The at least one conduit is for receiving a fluid. The at least one driver is for vibrating the at least one conduit. The at least one sensing element is used for measuring the action of the at least one pipeline. One or more electronics are configured to detect the process disturbance based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the void fraction and the void fraction threshold.

In yet a further embodiment of the present invention, a system for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device includes at least one conduit, at least one driver, at least one sensing element, and one or more electronics. The at least one conduit is for receiving a fluid. The at least one driver is for vibrating the at least one conduit. The at least one sensor is used to measure the motion of the at least one conduit. One or more electronics are configured to detect a process disturbance based on a comparison between the measured drive gain and a drive gain threshold and a comparison between the measured pickoff amplitude and a pickoff amplitude threshold.

Applications of

In accordance with one aspect of the present invention, a method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device includes the steps of:

measuring a drive gain;

determining the void ratio; and are

The presence of the process disturbance is detected based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the void fraction and the void fraction threshold.

Preferably, the comparison between the measured drive gain and the drive gain threshold comprises determining whether the measured drive gain is substantially equal to the drive gain threshold.

Preferably, the comparison between the measured drive gain and the drive gain threshold comprises determining whether the measured drive gain is less than the drive gain threshold.

Preferably, the comparison between the void fraction and the void fraction threshold value comprises determining whether the void fraction is less than the void fraction threshold value.

Preferably, the comparison between the void fraction and the void fraction threshold value comprises determining whether the void fraction is greater than the void fraction threshold value.

Preferably, the comparison between the measured drive gains includes determining whether the measured drive gains are substantially equal to a drive gain threshold, and the comparison between the void fraction and the void fraction threshold includes determining whether the void fraction is greater than a void fraction threshold.

Preferably, the method further comprises outputting information, recommending one or more actions, or performing one or more actions to reduce the severity of the process disturbance or reduce the adverse effect the process disturbance has on the accuracy of the characteristic measured by the vibrating flow device.

Preferably, the method further comprises detecting the presence of the process disturbance based on a comparison between the measured mass flow rate and a nominal mass flow rate threshold.

Preferably, the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is greater than the nominal mass flow rate threshold value.

Preferably, the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is less than the nominal mass flow rate threshold value.

Preferably, the comparison between the measured drive gain and the drive gain threshold value includes determining whether the measured drive gain is less than the drive gain threshold value, the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is greater than the nominal mass flow rate threshold value, and the comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is less than the void fraction threshold value.

Preferably, the comparison between the measured drive gain and the drive gain threshold value includes determining whether the measured drive gain is substantially equal to the drive gain threshold value, the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is less than the nominal mass flow rate threshold value, and the comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is less than the void fraction threshold value.

In accordance with another aspect of the present invention, a method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device includes the steps of:

measuring a drive gain;

measuring the amplitude of the sensitive element; and are

The presence of the process disturbance is detected based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the measured pickoff amplitude and the pickoff amplitude threshold.

Preferably, the comparison between the measured pick-off amplitude and the pick-off amplitude threshold includes determining whether the measured pick-off amplitude is greater than the pick-off amplitude threshold.

Preferably, the comparison between the measured pick-off amplitude and the pick-off amplitude threshold value includes determining whether the measured pick-off amplitude is less than the pick-off amplitude threshold value.

Preferably, the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold, and the comparison between the measured pick-off amplitude and the pick-off amplitude threshold includes determining whether the measured pick-off amplitude is greater than the pick-off amplitude threshold.

Preferably, the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold, and the comparison between the measured pick-off amplitude and the pick-off amplitude threshold includes determining whether the measured pick-off amplitude is less than the pick-off amplitude threshold.

In accordance with yet another aspect of the present invention, a computer program product comprises a computer usable medium having executable code embodied therein for performing a process for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device, the process comprising:

Preferably, the process further comprises detecting the presence of a process disturbance based on a comparison between the measured mass flow rate and a nominal mass flow rate threshold.

In accordance with a further aspect of the invention, a system for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device comprises:

at least one conduit for receiving a fluid;

at least one driver for vibrating the at least one conduit;

at least one sensor for measuring the motion of the at least one conduit;

one or more electronics to detect a process disturbance based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the void fraction and the void fraction threshold.

Preferably, the one or more electronics are configured to detect the presence of the process disturbance based on a further comparison between the measured mass flow rate and a nominal mass flow rate threshold.

In accordance with yet a further application of the present invention, a system for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device comprises:

at least one conduit for receiving a fluid;

at least one driver for vibrating the at least one conduit;

at least one sensor for measuring the motion of the at least one conduit;

one or more electronics to detect a process disturbance based on a comparison between the measured drive gain and a drive gain threshold and a comparison between the measured pickoff amplitude and a pickoff amplitude threshold.

Drawings

Fig. 1 shows a perspective view of a vibrating flow device in an embodiment of the invention.

Detailed Description

FIG. 1 shows an example of a vibrating flow device 5 in the form of a Coriolis flowmeter, including a sensor assembly 10 and one or more electronics 20. One or more electronic devices 20 are connected to the sensor assembly 10 by leads 100 to measure characteristics of the flowing substance such as density, mass flow rate, volumetric flow rate, total mass flow, temperature, and other information on the path 26.

The sensor assembly 10 in this example includes a pair of flanges 101 and 101'; manifolds 102 and 102'; a driver 104; the sensing element 105 and 105'; conduits 103A and 103B and support plate 120 and 124. Manifolds 102, 102' are secured to opposite ends of conduits 103A and 103B. Driver 104 and pickoffs 105 and 105' are connected to conduits 103A and 103B. The driver 104 is fixed to the conduits 103A, 103B at a position where the driver 104 is able to vibrate the conduits 103A, 103B relative to each other. The sensing elements are secured to the conduits 103A, 103B at opposite ends to detect phase differences in the vibrations at the opposite ends of the conduits 103A, 103B. It should be apparent to those skilled in the art that the principles described herein may be used in conjunction with any type of vibrating flow device, including, for example, densitometers, regardless of the number of conduits, the number of drives, the number of pickoffs, the mode of operation of the vibration, or the determined characteristics of the flowing material.

Flanges 101 and 101 'in this example are secured to manifolds 102 and 102' and connect lines 103A, 103B to a pipeline (not shown). Upon insertion of sensor assembly 10 into a pipeline system (not shown) carrying a flowing substance, the substance enters sensor assembly 10 through flange 101, passes through inlet manifold 102, where the entire amount of material is directed into conduits 103A and 103B, flows through conduits 103A and 103B, and then back to outlet manifold 102 ', where it exits sensor assembly 10 through flange 101'.

Conduits 103A and 103B are preferably selected and appropriately mounted to inlet manifold 102 and outlet manifold 102 ' to have substantially the same mass distribution, moment of inertia, and spring rate about bending axes W-W and W ' -W ', respectively. The tubes extend outwardly from the manifold in a substantially parallel manner. Although the conduits 103A, 103B are shown as being generally U-shaped, it is within the scope of the present invention to provide the conduits 103A, 103B in other shapes, such as straight lines or irregular shapes.

In this example, the conduits 103A-B are driven in opposite directions about their respective bending axes W and W' by the driver 104 and are in a so-called first out of phase bending mode of the meter. Driver 104 may comprise one of a variety of well-known devices, such as a magnet mounted to conduit 103A and a counter-acting coil mounted to conduit 103B. An alternating current is fed through the counter acting coil to cause the lines 103A, 103B to vibrate. Appropriate drive signals are applied by one or more of the electronic devices 20 to the driver 104 via leads 110.

In this example, one or more electronic devices 20 generate and transmit a drive signal to driver 104 via lead 110, which causes driver 104 to vibrate conduits 103A and 103B. However, it is within the scope of the present invention to generate multiple drive signals for multiple drivers. One or more electronic devices 20 process the left and right velocity signals from the pickoffs 105, 105' to calculate the mass flow rate. Path 26 provides input and output means to allow one or more electronic devices 20 to interact with an operator. The description of the circuitry of one or more of the electronic devices 20 is not necessary for an understanding of the present invention and is therefore omitted for simplicity of this description. Additionally, the description of FIG. 1 is provided merely as a working example of one possible vibrating flow device and should not be construed as limiting the teachings of the present invention.

According to one application of the present embodiment, the one or more electronic devices 20 are used to determine the presence of a process disturbance that occurs when bubbles or particulates are entrained in the fluid flowing through the conduits 103A, 103B. According to another application of the present embodiment, one or more electronic devices 20 are used to determine the severity of a process disturbance. More specifically, applicants have found that various combinations of certain parameters, particularly drive gain, mass flow rate, void fraction, and pickoff amplitude parameters, are very effective in determining the presence and severity of a process disturbance when compared to respective threshold values.

According to one application of the present embodiment, the presence and severity of a process disturbance may be confirmed by determining a relationship between a drive gain and a drive gain threshold. As used herein, the term drive gain refers to a measure of the amount of power required to drive the flow tube to a determined amplitude. This value can vary from a low nominal value of around 5% for single phase fluids to a value of 100% for multiphase fluids.

According to another application of the present embodiment, the presence and severity of a process disturbance may be confirmed by determining a relationship between a mass flow rate of a substance and a nominal mass flow rate threshold. As used herein, a nominal mass flow rate refers to a flow rate corresponding to a pressure drop of one atmosphere or 101.3kPa from the inlet to the outlet of the flow meter.

According to yet another application of this embodiment, the presence and severity of a process disturbance can be confirmed by determining a relationship between a porosity of a substance and a porosity threshold. As used herein, the term void fraction refers to the gas phase volume divided by the total volume of the flow tube.

According to yet another application of the present embodiment, the presence and severity of a process disturbance may be confirmed by determining a relationship between an amplitude of one or more pickoffs and a pickoff amplitude threshold. As used herein, the amplitude of a pick-off refers to the voltage of a pick-off signal generated by one or more pick-offs, such as pick-offs 105 and 105'.

In one embodiment of the invention, the presence and severity of a process disturbance may be confirmed by determining a relationship between a measured drive gain and a drive gain threshold, a relationship between a measured mass flow rate and a nominal mass flow rate threshold, and a relationship between a void fraction and a void fraction threshold. More specifically, in one embodiment of the invention, the presence and severity of a process disturbance may be confirmed by determining whether the measured drive gain exceeds a drive gain threshold, the measured mass flow rate exceeds a nominal mass flow rate threshold, and the void fraction is below a void fraction threshold. By way of example and not limitation, in one embodiment of the invention, a minor process disturbance may be identified when the following conditions are satisfied:

measured drive gain < 100%;

measured mass flow rate ("M") > nominal mass flow rate ("M_Nom") 0.04; and is

The porosity is less than 0.2.

In another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining a relationship between a measured drive gain and a drive gain threshold and a relationship between a measured amplitude of one or more pickoff signals and a pickoff amplitude threshold. More specifically, in another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining whether the measured drive gain is equal to a drive gain threshold and whether the measured amplitude of one or more pickoff signals exceeds a pickoff amplitude threshold. By way of example and not limitation, in one embodiment of the invention, the existence of a significant process disturbance may be confirmed when the following conditions are satisfied:

measured drive gain is 100%; and is

The measured pick-off amplitude ("PO") > 0.07 volts.

In yet another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining a relationship between a measured drive gain and a drive gain threshold, a relationship between a measured mass flow rate and a nominal mass flow rate threshold, and a relationship between a void fraction and a void fraction threshold. More specifically, in yet another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining whether the measured drive gain is equal to a drive gain threshold, whether the measured mass flow rate is less than a nominal mass flow rate threshold, and whether the void fraction is below a void fraction threshold. By way of example and not limitation, in yet another embodiment of the invention, the presence of a significant process disturbance may be confirmed when the following conditions are satisfied:

measured drive gain is 100%;

measured mass flow rate ("M") < nominal mass flow rate ("M_Nom") 0.04; and is

The porosity is less than 0.2.

In yet another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining a relationship between a measured drive gain and a drive gain threshold and a relationship between a measured amplitude of one or more pickoff signals and a pickoff amplitude threshold. More specifically, in yet another embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining whether the measured drive gain is equal to a drive gain threshold and whether the measured amplitude of one or more pickoff signals is less than a pickoff amplitude threshold. By way of example and not limitation, in yet another embodiment of the invention, a severe process disturbance may be identified when the following conditions are met:

measured drive gain is 100%; and is

The measured pick-off amplitude ("PO") < 0.07 volts.

In yet a further embodiment of the present invention, the presence and severity of a process disturbance may be confirmed by determining a relationship between a measured drive gain and a drive gain threshold and a relationship between a void fraction and a void fraction threshold. More specifically, in still further embodiments of the present invention, the presence and severity of a process disturbance may be confirmed by determining whether the measured drive gain is equal to a drive gain threshold and the void fraction exceeds a void fraction threshold. By way of example and not limitation, in yet further embodiments of the invention, a severe process disturbance may be identified when the following conditions are met:

measured drive gain is 100%; and is

The porosity is more than 0.2.

It should be understood by those skilled in the art that it is within the scope of the present invention to use one or more sets of electronics 20 to determine the presence and severity of a process disturbance through any one or any combination of the above disclosed relationships. Moreover, those skilled in the art will appreciate that determining the threshold value will depend on various factors such as, but not limited to, meter size, meter frequency, flow tube shape, flow tube size, electronics packaging, drive design, pickoff device design, mounting orientation, and various other meter design parameters. The specific threshold value may be determined empirically within the scope of the invention. For example, and without limitation, empirical testing and determination of the measurement performance of a meter under changing conditions on multiphase flow may be performed in flow equipment including a baseline liquid flow meter, a baseline gas flow meter, pressure sensors, temperature sensors, and other components necessary to change the above parameters. Thus, although the particular thresholds provided above are derived at an operating frequency of about 100Hz by using a curved tubular meter design, the present invention is not limited to the particular thresholds provided above as examples.

According to further example applications, one or more of the electronic devices 20 may be used to output certain information, recommend certain operations, or perform certain operations that may be used to reduce the severity of or the impact that a detected process disturbance has on generating accurate data. Those skilled in the art will appreciate that a variety of different levels of information may be known depending on user or program input and the type of vibrating flow device. The type of information or action generated by one or more electronic devices 20 may be affected by the known type of information.

By way of example and not limitation, the first level of information may include known information unrelated to user or program input. Depending on the type of vibrating flow device, the first level of information may include drive gain, pickoff amplitude ("PO"), mass flow rate ("M"), vibration frequency ("f"), temperature ("T"), nominal mass flow rate ("M"), and the like_Nom") and any meter alarms.

By way of example and not limitation, the second level of information may include information that is known if a user or program enters the liquid density. Depending on the type of vibrating flow device, the second level of information may include a coarse porosity and a ratio between measurement error due to acoustic effects during vibration of the tube and measurement error due to movement of the bubble relative to the liquid.

By way of example and not limitation, the third level of information may include if a user or program inputs line pressure ("P")_L"), line size, pressure drop, and liquid density are known information. Depending on the type of vibrating flow device, the third level of information may include a minimum fluid pressure ("P_min") and the vapor pressure of the fluid (" P_vapor”)。

By way of example and not limitation, the fourth level of information may include if the user or program inputIn-line pressure, line size, pressure drop, liquid density, and vapor pressure ("P") of the fluid at the line temperature_vapor") is known information. Depending on the type of vibrating flow device, the fourth level of information may include an indication as to whether cavitation or bubble infiltration into the flowing material is occurring.

By way of example and not limitation, according to a known level of information, one or more electronic devices 20 may output, recommend, or perform the following during minor process disturbances:

information level Operations output, recommended, or performed

1 increasing the pressure without decreasing the flow rate to decrease the volume fraction of the gas

If ρ (measured density) < ρ_L(assuming density) and f < 200Hz, then roughly

The gas volume fraction is (p)_L-ρ)/ρ_L50% of and (p)_L-ρ)/ρ_LOf 125% of

And (b), wherein:

2

f is the vibration frequency;

ρ ═ the density measured by the vibrating flow device; and

ρ_Lassumed fluid density (typically user input)

If the minimum static pressure in the meter is about P_minThen ensure the vapor of the fluid at T

Pressure less than P_minSo as to avoid the flash evaporation,

3, wherein:

t ═ temperature expressed in ° c; and

P_minfluid minimum pressure

If P is_vapor＞P_min(flash is expected), then the line pressure is increased or decreased

The temperature is such as to eliminate the gases from the process,

4, wherein:

P_vaporthe vapor pressure of the fluid; and

P_minfluid minimum pressure

By way of example and not limitation, depending on the level of known information, one or more electronic devices 20 may output, recommend, or perform the following during an apparent process disturbance:

information level Operations output, recommended, or performed

If M < 0.3 XM_nomThen the flow rate is increased to at least 0.5 xM_nom(is provided with

High flow rate may be desired for high accuracy in the presence of gas)

1 wherein:

m-mass flow rate; and

M_nomnominal mass flow rate

Directly increasing the degree of mixing upstream of the meter (for high accuracy in the presence of gas)

1

It may be desirable for the fluids to be well mixed)

If ρ (measured density) < ρ_L(assuming density) and f < 200Hz, then roughly

The gas volume fraction is (p)_L-ρ)/ρ_L50% of and (p)_L-ρ)/ρ_LOf 125% of

2

And (b), wherein:

f is the vibration frequency;

ρ ═ the density measured by the vibrating flow device; and

ρ_Lassumed fluid density (typically user input)

Pressure less than P_minSo as to avoid the flash evaporation,

3, wherein:

t ═ temperature expressed in ° c; and

P_minfluid minimum pressure

The temperature is such as to eliminate the gases from the process,

4, wherein:

P_vaporthe vapor pressure of the fluid; and

P_minfluid minimum pressure

By way of example and not limitation, depending on the level of known information, one or more electronic devices 20 may output, recommend, or perform the following during a severe process disturbance:

information level Operations output, recommended, or performed

High flow rate may be desired for high accuracy in the presence of gas)

1 wherein:

m-mass flow rate; and

M_nomnominal mass flow rate

1

It may be desirable for the fluids to be well mixed)

If PO < PO_KSThen the gas volume fraction is reduced (the instrument is not working properly)

Wherein:

PO ═ pick-off amplitude; and

1 PO_KSthreshold for the amplitude of the sensor, below which one or more of these values is/are exceeded

The electronics 20 determine that the conduit is not vibrating. Usually at PO falling below

PO_KSThe electronic device then changes the drive signal sent to the driver to attempt to drive

The vibration is generated. This correspondingly prevents accurate measurements during multiphase flow.

If ρ (measured density) < ρ_L(assuming density) and f < 200Hz, then roughly

2

The gas volume fraction is (p)_L-ρ)/ρ_L50% of and (p)_L-ρ)/ρ_LOf 125% of

And (b), wherein:

t ═ temperature expressed in ° c; and

P_minfluid minimum pressure

Pressure less than P_minSo as to avoid the flash evaporation,

3, wherein:

t ═ temperature expressed in ° c; and

P_minfluid minimum pressure

The temperature is such as to eliminate the gases from the process,

4, wherein:

P_vaporthe vapor pressure of the fluid; and

P_minfluid minimum pressure

Those skilled in the art will appreciate that the principles of the above-described embodiments may be written in a computer program product, such as software installed on one or more electronic devices 20.

This written description presents specific examples to teach those skilled in the art how to make and use the best mode of the invention. Some conventional matters have been simplified or omitted for the purpose of teaching the principles of the present invention. Those skilled in the art will appreciate that variations from these examples are also within the scope of the invention. The above detailed description of embodiments is not intended to be an exhaustive description of all embodiments understood by the inventors to fall within the scope of the invention. By way of example and not limitation, one or more electronic devices 20 may be remote from sensor assembly 10 and connected thereto in any manner, such as through an internet connection.

Those skilled in the art will appreciate that certain elements of the above-described embodiments may be combined or deleted with varying degrees to create further embodiments, and that such further embodiments are within the scope and teachings of the present invention. It will also be apparent to those skilled in the art that the above-described embodiments may be combined in whole or in part to form additional embodiments within the scope and teachings of the invention.

Thus, while specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. The teachings provided herein can be applied to other embodiments than those described above and illustrated in the drawings. Accordingly, the scope of the invention should be determined from the following claims.

Claims

1. A method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device (5), comprising the steps of:

measuring a drive gain, comparing the measured drive gain to a drive gain threshold;

determining the void fraction, and comparing the void fraction with a void fraction threshold; and are

The presence and severity of the process disturbance is determined based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the void fraction and the void fraction threshold.

2. The method for detecting a process disturbance according to claim 1, wherein the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold.

3. The method for detecting a process disturbance according to claim 1, wherein the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is less than the drive gain threshold.

4. The method for detecting a process disturbance according to claim 1, wherein the comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is less than the void fraction threshold value.

5. The method for detecting a process disturbance according to claim 1, wherein the comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is greater than the void fraction threshold value.

6. The method for detecting a process disturbance according to claim 1, wherein the comparison between the measured drive gain and the measured drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold, and the comparison between the void fraction and the void fraction threshold includes determining whether the void fraction is greater than the void fraction threshold.

7. The method for detecting a process disturbance according to claim 1, wherein the method further comprises outputting information, recommending one or more actions, or performing one or more actions to reduce the severity of the process disturbance or to reduce an adverse effect the process disturbance has on the accuracy of a characteristic measured by the vibrating flow device.

8. The method for detecting a process disturbance according to claim 1, wherein the method further comprises the steps of:

measuring a mass flow rate, comparing the measured mass flow rate to a nominal mass flow rate threshold; and are

The presence and severity of a process disturbance is determined from a comparison between the measured mass flow rate and a nominal mass flow rate threshold.

9. The method for detecting a process disturbance according to claim 8, wherein the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold.

10. The method for detecting a process disturbance according to claim 8, wherein the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is less than the drive gain threshold.

11. The method for detecting a process disturbance according to claim 8, wherein the comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is less than the void fraction threshold value.

12. The method for detecting a process disturbance according to claim 8, wherein the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is greater than the nominal mass flow rate threshold value.

13. The method for detecting a process disturbance according to claim 8, wherein the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is less than the nominal mass flow rate threshold value.

14. The method for detecting a process disturbance according to claim 8, wherein:

the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is less than the measured drive gain threshold;

the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is greater than the nominal mass flow rate threshold value; while

The comparison between the void fraction and the void fraction threshold value includes determining whether the void fraction is less than the void fraction threshold value.

15. The method for detecting a process disturbance according to claim 8, wherein:

the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold;

the comparison between the measured mass flow rate and the nominal mass flow rate threshold value includes determining whether the measured mass flow rate is less than the nominal mass flow rate threshold value; while

16. The method for detecting a process disturbance according to claim 8, wherein the method further comprises outputting information, recommending one or more actions, or performing one or more actions to reduce the severity of the process disturbance or to reduce an adverse effect the process disturbance has on the accuracy of the characteristic measured by the vibrating flow device.

17. A method for detecting a process disturbance generated by entrained gas or particulates within a fluid flowing in a vibrating flow device (5), comprising the steps of:

measuring the amplitude of the sensitive element, and comparing the measured amplitude of the sensitive element with the amplitude threshold value of the sensitive element; and are

The presence and severity of the process disturbance is determined based on a comparison between the measured drive gain and the drive gain threshold and a comparison between the measured pickoff amplitude and the pickoff amplitude threshold.

18. The method for detecting a process disturbance according to claim 17, wherein the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold.

19. The method for detecting a process disturbance according to claim 17, wherein the comparison between the measured pick-off amplitude and the pick-off amplitude threshold value includes determining whether the measured pick-off amplitude is greater than the pick-off amplitude threshold value.

20. The method for detecting a process disturbance according to claim 17, wherein the comparison between the measured pick-off amplitude and the pick-off amplitude threshold value includes determining whether the measured pick-off amplitude is less than the pick-off amplitude threshold value.

21. The method for detecting a process disturbance according to claim 17, wherein:

the comparison between the measured drive gain and the drive gain threshold includes determining whether the measured drive gain is substantially equal to the drive gain threshold; while

The comparison between the measured pick-off amplitude and the pick-off amplitude threshold includes determining whether the measured pick-off amplitude is greater than the pick-off amplitude threshold.

22. The method for detecting a process disturbance according to claim 17, wherein:

The comparison between the measured pick-off amplitude and the pick-off amplitude threshold includes determining whether the measured pick-off amplitude is less than the pick-off amplitude threshold.

23. The method for detecting a process disturbance according to claim 17, wherein the method further comprises outputting information, recommending one or more actions, or performing one or more actions to reduce the severity of the process disturbance or to reduce an adverse effect the process disturbance has on the accuracy of the characteristic measured by the vibrating flow device.

24. A system for determining the presence and severity of a process disturbance produced by entrained gas or particulates within a fluid flowing in a vibrating flow device (5), comprising:

at least one conduit (103A) for receiving a fluid;

at least one driver (104) for vibrating the at least one conduit (103A);

at least one sensor (105) for measuring the motion of said at least one line (103A);

one or more electronics (20) for measuring the drive gain, comparing the measured drive gain to a drive gain threshold, determining a void fraction, comparing the void fraction to a void fraction threshold, and detecting a process disturbance based on the comparison between the measured drive gain and the drive gain threshold and the comparison between the void fraction and the void fraction threshold.

25. The system for determining the presence and severity of a process disturbance according to claim 24, wherein the one or more electronics (20) are operable to measure a mass flow rate, compare the measured mass flow rate to a nominal mass flow rate threshold, and detect the presence of a process disturbance based on the comparison between the measured mass flow rate and the nominal mass flow rate threshold.

26. A system for determining the presence and severity of a process disturbance produced by entrained gas or particulates within a fluid flowing in a vibrating flow device (5), comprising:

at least one conduit (103A) for receiving a fluid;

at least one driver (104) for vibrating the at least one conduit (103A);

one or more electronics (20) for measuring the drive gain, comparing the measured drive gain to a drive gain threshold; the method further includes measuring a pickoff amplitude, comparing the measured pickoff amplitude to a pickoff amplitude threshold, and detecting the process disturbance based on the comparison between the measured drive gain and the drive gain threshold and the comparison between the measured pickoff amplitude and the pickoff amplitude threshold.