RU2431806C2 - Vibration flow rate meter and method of correcting entrained phase in two-phase fluid flow - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: proposed flow rate meter comprises entrained phase, flow rate meter assembly including drive and, additionally, measuring electronic hardware connected with flow rate meter assembly to receive vibration response. Note here that vibration meter allows correcting density of two-phase fluid flow. Flow rate meter assembly allows creating vibration response for fluid flow. Measurement hardware allows measuring fluid flow density via vibration signals from flow rate meter assembly, defining designed drive power and computing density compensation factor using fluid density of fluid component in two-phase flow, density of entrained phase and designed drive power. Note that entrained phase density is entrained component.

EFFECT: higher accuracy of measurements.

46 cl, 7 dwg

Description

Technical field

The invention relates to a vibrational flow meter and a method, in particular to a vibrational flow meter and a correction method for the entrained (flow) phase in a two-phase flow of a flowing material.

Description of the problem

The operation of sensors using vibrating channels, such as Coriolis mass flow meters and vibrating densitometers, is typically based on detecting movement of a vibrating channel that contains leaking material. Properties related to the material located in the channel, for example mass flow, density, and the like, can be determined by processing measurement signals received from motion detecting sensors that are associated with the channel. The vibration modes of a system filled with vibrating material are generally affected by a combination of mass, stiffness and damping characteristics of the channel containing the material and the material itself.

A typical Coriolis mass flow meter includes one or more channels that are integrated in a pipeline or other conveying system and transport material, such as fluid, suspensions, emulsions, and the like, in this system. Each channel can be considered as having a set of natural vibration modes, including, for example, simple bending, twisting, radial modes and their combinations. In a typical application of the Coriolis mass flow measurement, the channel is excited in one or more vibration modes when the material flows through it, and the movement of the channel is measured at different points along the channel. Excitation, as a rule, is provided by an actuator, for example, an electromechanical device, such as a generator of sound waves in the form of a coil, which generates disturbances in the channel in a periodic manner. Mass flow can be determined by measuring the time delay or the phase difference between movements at the locations of the sensing elements. In order to measure the vibrational response of a channel or channels with a flow, as a rule, two such sensitive elements (or sensors for measuring mechanical displacements) are used, which are located in the positions above and downstream relative to the actuator. Two sensors for measuring mechanical displacements are connected to electronic equipment using wire connections, for example, two independent pairs of wires. The equipment receives signals from the two sensors for measuring mechanical displacements and processes the signals to obtain a mass flow measurement.

Flow meters are used to perform mass flow measurements for a wide range of fluid flows. One area in which Coriolis flow meters can be used is the measurement of the characteristics of oil and gas wells. Product extracted from such wells may contain a multiphase flow including oil or gas, as well as other components, such as water and air and / or solids. It is highly desirable that the resulting measurements are as accurate as possible, even for such multiphase flows.

Coriolis meters provide high accuracy for single-phase flows. However, when a Coriolis flow meter is used to measure the characteristics of aerated fluids or fluids including entrained gas (emulsions) in them, the accuracy of the meter can be significantly degraded. This is also true for immersed solids (suspensions).

Entrained air is usually present in the flowing material in the form of bubbles. The size of the bubbles can vary depending on the amount of air available, the pressure of the flowing material, as well as the temperature. The degree of deterioration is associated not only with the total amount of gas present, but also with the size of the individual gas bubbles in the stream. The size of the bubbles affects the accuracy of the measurement.

One significant source of error is fluid separation. The separation of the fluid occurs as a result of the movement of gas bubbles relative to the liquid due to vibration of the pipe. The movement of gas bubbles relative to the liquid is generated by a buoyancy force similar to the force that causes the bubbles to rise to the surface under the influence of gravity. However, in a vibrating tube, the movement of the bubbles is caused by the acceleration of the tube, and not by the acceleration of gravity. Since the dense fluid resists acceleration more than light bubbles, the bubbles are accelerated in the same direction as the direction of acceleration of the pipe. Therefore, the bubbles move faster and farther than the tube in which the flow moves, and the movement of the bubbles causes some of the fluid to move slower than the tube. This is the problem of separation. As a result, a fluid having a lower vibration amplitude undergoes less Coriolis acceleration and has less Coriolis force acting on the flow tube than it would be if there were no bubbles. This results in lower flow rates and densities than reported (negative errors for flow and density) in the presence of entrained air.

In suspensions, a problem similar to separation occurs. However, in the case of suspensions, solids are often heavier than liquids. Under the acceleration of the vibrating tube, heavier particles move to a lesser extent than liquid. This leads to the fact that some of the fluid moves to a greater extent than the vibrating tube. As a result, the liquid characteristics are higher than the reported ones (positive errors for the values of flow and density) in the presence of particles heavier than the liquid. In both cases, due to the difference in density between the entrained phase and the liquid, a relative displacement of the entrained phase occurs. If we neglect the compressibility of gases, then the same equations can be used to describe the behavior of both entrained air and immersed particles. Subtracting the density of the entrained phase from the density of the liquid gives positive values for gases and negative values for solids. The separation of the suspensions is simply negative. For this reason, the term "separation" will be used on an equal footing for both emulsions and suspensions.

It is difficult to compensate for the separation of the fluid, since there are several factors that determine how many bubbles move relative to the fluid. The obvious factor is the viscosity of the fluid. In a very viscous fluid medium, bubbles (or particles) essentially freeze in place in this medium, and minor errors in flow characteristics occur.

Another factor affecting the mobility of the bubbles is their size. Inhibition of the bubble is proportional to the surface area, while the buoyancy force is proportional to the volume. Thus, very small bubbles have a high braking to buoyancy ratio and tend to move with the fluid. As a result, small bubbles cause small errors. Conversely, large bubbles do not tend to move with the fluid and lead to large errors. The same holds true for particles. Small particles tend to move with the fluid and cause small errors.

Another factor is the difference in density between the fluid and the gas. The buoyancy force is proportional to the difference in density between the fluid and the gas. A gas having a high pressure may have a density high enough to affect the buoyancy force and reduce the separation effect. In addition, large bubbles occupy more volume, which leads to real fluctuations in the density of the flowing material. Due to the compressibility of the gas, the amount of gas in the bubbles can vary, but their size will not necessarily change. Conversely, if the pressure changes, the size of the bubbles, which expand when the pressure drops or shrink when the pressure increases, can accordingly change. It can also cause changes in the natural or resonant frequency of the flow meter and, thus, changes in the actual density of the two-phase flow.

Second-order factors can also affect the mobility of a bubble and particles. Turbulence in a fluid having a high flow rate destroys large bubbles and particles into smaller ones, which reduces the error due to separation. Surfactants reduce the surface tension of the bubbles and reduce their tendency to combine. Valves can reduce the size of the bubbles due to increased turbulence, while turns in the pipelines can increase the size of the bubbles by forcing them to combine due to centrifugal force.

There remains a need in the art for a vibratory flow meter that detects problematic levels of materials that are involved in the second phase. There remains a need in the art for a vibratory flow meter that can accurately measure flow characteristics in the presence of materials that are carried away by the second phase. There remains a need in the art for a vibratory flow meter that can accurately measure flow characteristics at different levels of materials, which are a passionate second phase.

SUMMARY OF THE INVENTION

According to one embodiment of the present invention, there is provided a vibratory flow meter for correction for a entrained phase in a two-phase flow of a flowing material. The vibrational flow meter comprises a flow meter assembly including a drive, wherein the vibrational flow meter is configured to create a vibrational reaction for the flowing material. The vibratory flow meter further comprises measuring electronics connected to the flow meter assembly and receiving a vibrational response. Measuring electronics is configured to create a measured density of a two-phase flow using a vibrational reaction, to determine the design power of the drive consumed by the drive, which is part of the flow meter assembly, and to calculate the density compensation coefficient using the density of the liquid, which is the liquid component of the two-phase flow, the density of the entrained phase, being a keen component, measured two-phase flow density and rated drive power.

According to one embodiment of the present invention, there is provided a correction method for a entrained phase in a two-phase flow of a flowing material in a vibratory flow meter. The method includes creating a measured density of a two-phase flow, determining the estimated drive power consumed by the drive that is part of the flow meter assembly, and calculating a density compensation coefficient using the density of the liquid being the liquid component of the two-phase flow, the density of the entrained phase being the entrained component, the measured density of the two-phase flow and rated drive power.

According to one embodiment of the present invention, there is provided a correction method for a entrained phase in a two-phase flow of a flowing material in a vibratory flow meter. The method comprises creating a measured density of a two-phase flow, determining an estimated drive power consumed by a drive included in a flow meter assembly, calculating a density compensation coefficient using a density of a liquid being a liquid component of a two-phase flow, a density of a entrained phase being a entrained component, a measured density of a two-phase flow and calculated drive power, and adding a density compensation factor to the measured two-phase flow density so that get the compensated density of the two-phase flow. The method further comprises determining the estimated drive power using the density of the liquid component, the density of the entrained component, the compensated density of the two-phase flow, and the power indicator of the vibratory flow meter. The method further comprises determining the accuracy of the flow measurements performed by the vibratory flow meter based on the difference between the estimated drive power and the calculated drive power.

Features of the invention

According to one of the distinguishing features of the vibratory flow meter, the measuring electronics is configured to multiply the drive voltage by the drive current in order to determine the design power of the drive.

According to another distinguishing feature of the vibratory flow meter, the measuring electronics is configured to multiply the voltage of the interference sensor by the drive current to determine the design power of the drive.

чтобы определить расчетную мощность привода, где K - постоянная пропорциональности, I_d - измеренный ток привода, I₀ - ток привода для доли с нулевым объемом, Е_PO - напряжение датчика для измерения механических перемещений, и E_t - плановое напряжение датчика для измерения механических перемещений.According to another distinctive feature of the vibratory flow meter, the measuring electronics is configured to solve the equation

to determine the calculated drive power, where K is the proportionality constant, I _d is the measured drive current, I ₀ is the drive current for a fraction with zero volume, E _PO is the sensor voltage for measuring mechanical displacements, and E _t is the planned sensor voltage for measuring mechanical displacements.

причем ρ_l - плотность жидкости, ρ_uut - указанная плотность, ρ_е - плотность увлеченной фазы, P_computed - расчетная мощность привода, а члены Сl и С2 содержат заранее определенные постоянные, зависящие от измерителя.According to the following distinctive feature of the vibratory flow meter, the calculation of the density compensation coefficient contains a solution to the equation

moreover, ρ _l is the fluid density, ρ _uut is the indicated density, ρ _e is the density of the entrained phase, P _computed is the calculated drive power, and the terms Cl and C2 contain predetermined constants depending on the meter.

According to yet another distinguishing feature of the vibratory flow meter, the meter electronics is further configured to add a density compensation coefficient to the measured density of the two-phase flow to provide a compensated density of the two-phase flow.

According to a further distinguishing feature of the vibratory flow meter, the measuring electronics is further configured to add a density compensation coefficient to the measured density of the two-phase flow to provide a compensated density of the two-phase flow, to determine the estimated drive power using the fluid density, entrained phase density, compensated two-phase flow density and index power of the vibratory flow meter, and also determine the exact ость flow measurements carried out by a vibratory flow meter based on the difference between the estimated drive power and the calculated drive power.

, где ρ_comp - компенсированная плотность двухфазного потока, чтобы получить компенсированную объемную долю для двухфазного потока.According to another distinctive feature of the vibratory flow meter, the measuring electronics is further configured to solve the equation

where ρ _comp is the compensated density of the two-phase flow in order to obtain the compensated volume fraction for the two-phase flow.

According to the following distinctive feature of the vibratory flow meter, determining the accuracy further comprises creating an alarm message if the calculated drive power differs from the estimated drive power by more than a predetermined deviation.

According to another distinguishing feature of the vibratory flow meter, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of entrained phase and further indicating the need to change the flow conditions in the vibration flow meter.

According to the following distinctive feature of the vibratory flow meter, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating excessive size of gas bubbles and additionally indicating the need to change the flow conditions in the vibratory meter expense.

According to yet another distinguishing feature of the vibratory flow meter, determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of solid entrained phase and further indicating the need to change the flow conditions in vibratory flow meter.

According to a further distinguishing feature of the vibratory flow meter, the determination of accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value.

According to another distinguishing feature of the vibratory flow meter, the determination of accuracy further comprises clarifying the compensated density of the two-phase flow if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value or if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value.

According to the following distinctive feature of the vibrational flow meter, the refinement of the compensated density of a two-phase flow comprises a decrease in the density compensation coefficient by an amount proportional to the difference between the calculated drive power and a predetermined lower limit value.

According to another distinctive feature of the vibrational flow meter, the accuracy determination further compares the estimated drive power with the calculated drive power, generates an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, and clarifies the compensated two-phase flow density by decrease the density compensation coefficient by an amount proportional to the difference between the calculated NOSTA actuator and a predetermined lower limit value, if the calculated drive power is less than anticipated driving power by more than a predetermined lower limit value.

According to one of the distinguishing features of the method, determining the design power of the drive comprises multiplying the drive voltage by the drive current.

According to another distinguishing feature of the method, determining the design power of the drive comprises multiplying the voltage of the sensor for measuring mechanical displacements by the current of the drive.

According to another distinctive feature of the method, the determination of the design power of the drive contains a solution to the equation

where K is the proportionality constant, I _d is the measured drive current, I ₀ is the drive current for a fraction with zero volume, E _PO is the sensor voltage for measuring mechanical displacements, and E _t is the planned sensor voltage for measuring mechanical displacements.

причем ρ_l - плотность жидкости, ρ_uut - указанная плотность, ρ_е - плотность увлеченной фазы, P_computed - расчетная мощность привода, а элементы С1 и С2 содержат заранее определенные постоянные, зависящие от измерителя.According to the following distinctive feature of the method, the calculation of the density compensation coefficient contains a solution to the equation

moreover, ρ _l is the fluid density, ρ _uut is the indicated density, ρ _e is the density of the entrained phase, P _computed is the calculated drive power, and elements C1 and C2 contain predetermined constants depending on the meter.

According to yet another distinguishing feature of the method, the method further comprises adding a density compensation coefficient to the measured density of the two-phase flow to provide a compensated density of the two-phase flow.

According to a further distinguishing feature of the method, the method further comprises adding a density compensation coefficient to the measured density of the two-phase flow to provide a compensated density of the two-phase flow, determining the estimated drive power using the fluid density, entrained phase density, compensated two-phase flow density, and a power indicator of the vibratory flow meter, and also determine the accuracy of the flow measurements made by the vibration meter flow rate based on a difference between the assumed value of the drive power and the calculated drive power.

, где ρ_comp - компенсированная плотность двухфазного потока, чтобы получить компенсированную объемную долю для двухфазного потока.According to another distinctive feature of the method, the method further comprises solving the equation

where ρ _comp is the compensated density of the two-phase flow in order to obtain the compensated volume fraction for the two-phase flow.

According to a further distinguishing feature of the method, determining the accuracy further comprises creating an alarm message if the calculated drive power differs from the estimated drive power by more than a predetermined deviation.

According to another distinctive feature of the method, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of entrained phase and further indicating the need to change the flow conditions in the vibratory flow meter .

According to a further distinguishing feature of the method, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive size of gas bubbles and further indicating the need to change the flow conditions in the vibratory flow meter.

According to another distinctive feature of the method, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of solid entrained phase and further indicating the need to change the flow conditions in the vibration meter expense.

According to a further distinguishing feature of the method, determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value.

According to another distinguishing feature of the method, the determination of accuracy further comprises clarifying the compensated density of the two-phase flow if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value or if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value .

According to a further distinguishing feature of the method, the refinement of the compensated density of a two-phase flow comprises a decrease in the density compensation coefficient by an amount proportional to the difference between the calculated drive power and a predetermined lower limit value.

According to another distinguishing feature of the method, determining the accuracy further comprises comparing the estimated drive power with the calculated drive power, creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, and refining the compensated density of the two-phase flow by reducing the coefficient density compensation by an amount proportional to the difference between the calculated drive power and in advance EFINITIONS lower limit value, if the calculated drive power is less than anticipated driving power by more than a predetermined lower limit value.

Description of drawings

Figure 1 shows a vibrational flow meter, intended for correction for the entrained phase in a two-phase flow of flowing material, according to one embodiment of the present invention.

Figure 2 shows the measuring electronics of a vibratory flow meter, according to one embodiment of the present invention.

Figure 3 is a flowchart of a correction method for a entrained phase in a two-phase flow of flowing material in a vibratory flow meter, according to one embodiment of the present invention.

4 is a flowchart of a correction method for a entrained phase in a two-phase flow of flowing material in a vibratory flow meter, according to one embodiment of the present invention.

Figure 5 is a graph of the dependence of the drive power on the volume fraction of gas obtained experimentally for many parameters of the fluid and in the range of volume fractions.

6 is a graph of the calculated drive power and the estimated drive power versus volume fraction of the entrained phase.

Fig.7 is a graph of the estimated drive power and the estimated drive power, similar to Fig.6, except that the estimated drive power is shown to have a lower value compared to the estimated drive power.

Detailed Description of Preferred Embodiments

1-7 and the following description illustrate specific examples in order to teach specialists in this field of technology how to implement and use the best implementation of the present invention. In order to teach innovative principles, some common aspects are simplified or omitted. Modifications of these examples will be apparent to those skilled in the art that do not fall outside the scope of the present invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to obtain many modifications of the present invention. As a result, the present invention is not limited to the specific examples described below, but only by the appended claims and their equivalents.

Figure 1 shows a vibrational flow meter 5, intended for correction for the entrained phase in a two-phase flow of flowing material, according to one embodiment of the present invention. The entrained phase may contain entrained gas. The entrained phase may contain an immersed solid. The discussion below focuses on entrained gas. However, this discussion also applies to immersed solids.

The vibratory flow meter 5 comprises a flow meter assembly 10 and a measurement electronics 20. The measurement electronics 20 are connected to the meter assembly 10 via terminals 100 and are configured to provide measurements of one or more of the following: density, mass flow, volume flow, generalized mass flow, temperature and other information, on the link 26. It will be apparent to those skilled in the art that the present invention can be used in any type of Coriolis flow meter, regardless of the number of actuators, sensors for measuring mechanical displacements, flow channels, or vibration operating conditions. In addition to this, it should be understood that the vibratory flow meter 5 may alternatively comprise a vibratory density meter.

The flow meter assembly 10 includes a pair of flanges 101 and 101 ', manifolds 102 and 102', a drive 104, sensors 105 and 105 'for measuring mechanical displacements, and flow channels 103A and 103B.

Flanges 101 and 101 'are attached to manifolds 102 and 102'. The manifolds 102 and 102 'may be attached to opposite ends of the intermediate member 106. The intermediate member 106 maintains the distance between the manifolds 102 and 102' to prevent the transfer of forces from the pipeline to the flow channels 103A and 103B. When the flow meter assembly 10 is inserted into a conduit (not shown) that conveys a flowing material whose characteristics are measured, the flowing material enters the flow meter assembly 10 through a flange 101, passes through the intake manifold 102, where the entire amount of flowing material is directed to the inlet to the channels 103A and 103B of the flow, flows through the channels 103A and 103B of the flow and back to the exhaust manifold 102 ', where he leaves the node 10 of the meter through the flange 101'.

Channels 103A and 103B are selected and suitably connected to the intake manifold 102 and the exhaust manifold 102 ′ so that there are substantially the same mass distribution, moments of inertia, and elastic moduli for the W-W and W′-W ′ axes, respectively. The flow channels 103A and 103B extend in the direction from the manifolds 102 and 102 'substantially in parallel.

The flow channels 103A and 103B are driven by the actuator 104 in opposite directions with respect to the respective bending axes W and W ′ and in a mode called the “first bending mode out of phase” of the vibratory flow meter 5. The actuator 104 may have one of many well-known designs, for example, a magnet mounted on the flow channel 103A and an opposite coil mounted on the flow channel 103B. An alternating current is passed through the opposite coil to cause both channels to oscillate. A suitable drive signal is supplied by measuring electronics 20 to the actuator 104 through terminal 110.

Measuring electronics 20 receives sensor signals at terminals 111 and 111 ', respectively. The meter electronics 20 generates a drive signal at terminal 110, which causes the actuator 104 to oscillate flow channels 103A and 103B. Measuring electronics 20 processes the left and right speed signals from sensors 105 and 105 'to measure mechanical displacements in order to calculate the mass flow rate. The communication line 26 provides an input / output means that allows the measuring electronics 20 to interact with the operator or other electronic systems. The description for FIG. 1 is provided merely as an example of the operation of a Coriolis flow meter and does not imply a limitation on the idea of the present invention.

The node 10 of the flow meter is configured to create a vibrational reaction for the flowing material. The measurement electronics 20 may receive and process a vibrational reaction to create one or more flow measurements for the flowing material, including a two-phase flow. A two-phase flow may include entrained gas (including entrained air) or entrained solids. The vibratory flow meter 5 is configured to correct for entrained gas and solids to obtain reliable and accurate flow measurements despite the entrained phase. In some embodiments of the present invention, the measurement electronics 20 can receive and process a vibrational response to generate an alarm message if the entrained phase level in the flow meter assembly 10 exceeds a predetermined limit value (see FIG. 4 and related discussion). An alarm message may indicate an excessive level of entrained phase. An alarm message may indicate an excessive size of the bubbles, for example, if the size of the bubbles exceeds a predetermined limit size, or the volume of gas. An alarm message may indicate an excessive particle size or solid volume. Thus, an alarm message may indicate that one or more flow measurements have exceeded a predetermined deviation for the measurements. In some embodiments of the present invention, the measurement electronics 20 may refine the correction if the resulting measurement (s) of the flow is not sufficiently accurate.

One common problem in creating one or more flow measurements occurs when entrained air (or any gas) is in the flowing material. Entrained air may be present as bubbles of various sizes. When bubbles are relatively small, they have a negligible effect on flow measurements. However, as the size of the bubbles increases, the error in the flow measurements also increases.

Measuring electronics 20, in accordance with some embodiments of the present invention, provides improved flow measurement. The flow measurement is improved when a entrained phase is present in the flowing material. Flow measurement is improved when submerged air bubbles are present in the flowing material. Flow measurement is improved when entrained solid is present in the flowing material. For example, measurement electronics 20 may provide improved density measurement of flowing material. The meter electronics 20 may further provide a volume fraction of the entrained phase and / or other flow measurements for the flowing material. As a result, the vibratory flow meter 5 may comprise a vibratory densitometer and / or a Coriolis flow meter. Other additional flow measurements can be obtained, and they do not go beyond the scope of this description and the appended claims of the present invention.

In one embodiment of the present invention, the flow tubes 103A and 103B, as shown, are substantially U-shaped. Alternatively, in other embodiments of the present invention, the flow tubes may be substantially straight. However, you can also use other forms that are not beyond the scope of this description and the appended claims of the present invention.

Measuring electronics 20 in one embodiment of the present invention is configured to generate vibration in the flow tubes 103A and 103B. Vibration is realized by the actuator 104. Further, the measuring electronics 20 receives the resulting vibrational signals from the sensors 105 and 105 'for measuring mechanical displacement. Vibration signals comprise a vibrational reaction of the flow tubes 103A and 103B. Measuring electronics 20 processes the vibrational response and performs one or more flow measurements.

Figure 2 shows the measuring electronics 20 of a vibratory flow meter 5, according to one embodiment of the present invention. The measurement electronics 20 in this embodiment includes an interface 201 that can be connected to the terminals 100 (and, if desired, also to the communication line 26). Measuring electronics 20 further includes a processing system 203. Processing system 203 may be of any type, including a conventional or special purpose processor, circuit design, etc. The processing system 203 receives signals from the flow meter assembly 10 and processes these signals, for example, a vibrational response from sensors 105 and 105 'to measure mechanical displacement. The processing system 203 can further create and transmit signals to the flow meter assembly 10, for example, a drive signal that makes the drive 104 function.

Measuring electronics 20 may further include a storage system 204 that stores information. Storage system 204 may be integral with or separate from processing system 203. Storage system 204 may store, for example, vibrational response 211, measured two-phase flow density 212, liquid density 213, calculated drive power 214, density compensation coefficient 215, compensated two-phase flow density 216, estimated drive power 217 and entrained phase density 218. Other information may be stored in storage system 204, including the values discussed below.

The vibrational reaction 211 may comprise a vibrational reaction of the flow meter assembly 10. The vibrational response 211 may comprise signals from sensors for measuring mechanical displacement, which are processed to obtain a flow measurement. Thus, the vibrational reaction 211 may comprise a flow measurement, including one or more of the following: mass flow and volume flow. The flow rate (s) can be stored as part of the vibrational reaction 211 or can be stored as a separate value.

The measured density 212 of the two-phase flow contains a density measurement obtained from sensors 105 and 105 'for measuring mechanical displacement. The measured density 212 of the two-phase flow contains a measurement of the density of the two-phase flow, performed in the node 10 of the flow meter by a method known in the art. As a result, as the amount of entrained air in the two-phase flow increases, the measured density 212 of the two-phase flow becomes less accurate.

The density 213 of the liquid, which is the liquid component of the two-phase flow, contains the known density of the liquid component of the two-phase flow. The density 213 of the liquid may contain a stored value or a constant depending on the liquid component.

The density 218 of the entrained phase contains the known density (ρ _e ) of the entrained component of the two-phase flow, which is the second phase. The entrained phase density 218 may comprise a stored value or a constant depending on the entrained component.

The calculated drive power 214 contains the electrical power required by the actuator 104. The actuator 104 may receive all or not all the necessary electric power, depending on the amount of entrained air. The calculated drive power 214 may comprise a calculated or measured value that is stored by the processing system 203. The calculated drive power 214 may comprise the drive current multiplied by the drive voltage (i.e., the electric current flowing through the drive 104 multiplied by the electric voltage in the drive). Alternatively, if the voltage in the actuator 104 is not measured or otherwise known, the rated power 214 of the actuator may comprise the drive current multiplied by the voltage in one of the sensors for measuring mechanical displacement. However, this approach also has drawbacks, since the drive current is generally not unlimited and may not increase beyond a certain level even though it may be required. Thus, the calculated drive power 214 can be calculated in accordance with other values (see step 302 in FIG. 3 below).

The density compensation coefficient 215 comprises a compensation coefficient that will compensate for the measured density 212 of the two-phase flow when influenced by a entrained phase, such as entrained gas, for example. However, the gas may vary, and the density compensation coefficient 215 can compensate for any gas or mixture of gases. Density compensation coefficient 215 takes into account the presence of entrained gas. Density compensation coefficient 215 allows for varying levels of entrained gas.

The compensated density 216 of the two-phase flow contains the density value for the two-phase flow. In some embodiments, the compensated biphasic density 216 comprises a measured biphasic density 212 in combination with a density compensation factor 215.

Estimated drive power 217 comprises drive power that is expected to be absorbed by the compensated two-phase flow density with an average bubble size or other expected fluid parameters such as average viscosity, fluid density, etc. The estimated drive power 217 comprises drive power calculated using the compensated two-phase flow density 216.

In operation, and in accordance with one embodiment of the present invention, the processing system 203 receives a vibrational response 211, creates a measured two-phase flow density 212 based on the vibrational response, and performs at least density correction for the entrained phase (see FIG. 3 and 4 and related discussion).

FIG. 3 is a flowchart 300 of a correction method for a entrained phase in a two-phase flow of flowing material in a vibratory flow meter, according to one embodiment of the present invention. At step 301, a vibratory flow meter measures the density of the two-phase flow to obtain a measured density of the two-phase flow. As previously discussed, the measured density of the two-phase flow can be characterized by a different degree of error depending on the level of the entrained phase, flow rate, and other parameters of the flowing material.

At step 302, the calculated drive power is determined. The design power of the drive is the electrical power that the drive of the vibratory flow meter needs to drive to vibrate the flow channel (s). The calculated drive power in one embodiment of the present invention can be determined by multiplying the drive current by the drive voltage. Alternatively, the calculated drive power can be determined by multiplying the drive current by the voltage available in one of the sensors for measuring mechanical displacement. The voltage in the sensor for measuring mechanical displacement can be an acceptable substitute for the voltage of the drive, since in a vibration meter, the voltage of the drive is usually not measured or not determined, while the voltage in the sensor for measuring mechanical displacement is measured and known.

However, the power required to drive the channel (s) of the flow is proportional to the square of the amplitude of the vibration. Therefore, if the planned amplitude is doubled, the power required to achieve the planned amplitude of the vibration increases four times. Unfortunately, the current (I _d ) of the drive will not exceed the current capacity of the connected power source, and the drive will not be able to obtain the required current level of the drive in order to properly activate the channel (s) of the flow, especially when there are high currents in the two-phase flow entrained phase levels. Therefore, the design power of the drive may contain the power needed by the drive to cause the channel (s) of the stream to vibrate in full, instead of the power consumed by the drive. Therefore, the drive may require more power than is supplied.

The calculated drive power calculated in accordance with this embodiment of the present invention contains the power necessary to cause the flow channel (s) to vibrate in full, even if the available electric current is insufficient. The calculated drive power is calculated in accordance with the equation:

where K is the proportionality constant for the vibratory flow meter, I _d is the measured drive current, I ₀ is the drive current for a fraction with zero volume (such as calibration current), E _PO is the measured sensor voltage for measuring mechanical displacements, and E _t is the planned Sensor voltage for measuring mechanical movements. By solving equation (1), the calculated drive power is determined due to the presence of the entrained phase.

The term I _d × E _PO represents power proportional to the total power consumption of the drive. Strictly speaking, in order to calculate the drive power, instead of the voltage E _{PO of the} sensors, the drive voltage EMF must be used to measure mechanical displacement. However, the voltage EMF of the drive is difficult to measure, while the easily measured voltage E _{PO of the} sensor for measuring mechanical displacement is proportional to this voltage EMF. Therefore, an E _PO sensor can be used in the equation to measure mechanical displacement. This is the product of the voltage E _{PO of the} sensor for measuring the mechanical displacement by the current I _{d of the} drive in proportion to the power needed to cause vibration of the flow tube (s). The planned voltage E _{t of the} sensor for measuring mechanical displacement corresponds to a given vibration amplitude. The current I _{d of the} drive is usually adjusted to keep the voltage of the sensor for measuring mechanical displacement at a planned level, and, as a result, the amplitude of the vibration is at its planned level. However, entrained gas bubbles or entrained solids moving inside the fluid exert large damping forces on the vibrating flow tube (s), whereby the drive current limit is often reached before the voltage E _{PO of the} sensors for measuring mechanical displacement reaches its intended value E _t . If this happens, the voltage E _{PO of the} sensors for measuring mechanical displacement is less than the planned voltage E _t and the vibration amplitude is less than its planned level.

регулирует мощность привода в случае уменьшения амплитуды вибрации из-за достижения током привода своего предела. Другими словами, мощность, вычисленная в уравнении (1), представляет собой мощность, которая потребовалась бы для поддержания амплитуды вибрации на плановом уровне, даже несмотря на то, что эта мощность недоступна. Когда амплитуда вибрации находится на плановом уровне, то Е_PO=E_t и член отношения напряжений равен 1.Amplitude Ratio

adjusts the drive power in case of a decrease in the amplitude of vibration due to the drive current reaching its limit. In other words, the power calculated in equation (1) is the power that would be required to maintain the vibration amplitude at the planned level, even though this power is not available. When the amplitude of the vibration is at the planned level, then E _PO = E _t and the term stress ratio is 1.

The last term of equation (1), the term I ₀ × E _t , is the power at zero void fraction necessary to drive the flow meter without a second phase (gas or solid). This member may contain a power value calibrated at the factory. It is necessary to subtract the power at zero fraction of voids from the full power, because a pure liquid gives a very small mass flow rate error or does not give it at all. Thus, equation (1) calculates the increase in power due to the entrained phase. This increase in a first approximation is proportional to the error due to this phase. Power at a fraction with a zero volume can be determined during calibration at the factory.

At 303, a density compensation coefficient is calculated. The density compensation coefficient can be calculated in accordance with the equation:

density compensation factor =

, где ρ_е - плотность увлеченной фазы. Постоянные С1 и С2 могут быть определены для измерителя расхода конкретного типа. Для одного из типов измерителя расхода было экспериментально определено, что С1=0,66 и С2=0,0015. Однако необходимо понимать, что данные две постоянные могут меняться в соответствии с размерами, типом и т.п. измерителя расхода.where ρ _uut is the density uncorrected by the meter (i.e., measured or indicated), ρ _l is the known fluid density, P _computed is the calculated drive power from equation (1). The uncorrected density ρ _{uut is} corrected for a function of the uncorrected volume fraction

where ρ _e is the density of the entrained phase. Constants C1 and C2 can be defined for a specific type of flow meter. For one type of flow meter, it was experimentally determined that C1 = 0.66 and C2 = 0.0015. However, it must be understood that these two constants may vary according to size, type, etc. flow meter.

Equation (2) of density compensation can be obtained based on the output parameters of the meter, namely, the calculated drive power and the indicated / measured volume fraction. It should be noted that the density ρ _{l of the} liquid and the density ρ _{e of the} entrained component must be known in order to obtain an uncorrected volume fraction based on the measured density of the two-phase flow. Note that in the case where the entrained component is a gas under low pressure, its density can be approximated as zero with a slight deterioration in compensation or without it. Also note that a unique compensation equation may be required for each type of meter.

In step 304, a density compensation coefficient is combined with the density of the two-phase flow measured in step 301 to obtain a compensated density ρ _{comp of the} two-phase flow. The compensated biphasic flow density more accurately reflects the biphasic flow density compared to the measured biphasic flow density. The compensated two-phase flow density minimizes the effect of entrained air on the measurement of flow characteristics. The compensated density of the two-phase flow minimizes the effect of larger bubbles on the measurement of flow characteristics.

4 is a flowchart 400 of a correction method for a entrained phase in a two-phase flow of flowing material in a vibratory flow meter, according to one embodiment of the present invention. At step 401, a vibratory flow meter measures the density of the two-phase flow to obtain a measured density of the two-phase flow, as discussed previously.

At 402, the estimated drive power is determined, as previously discussed.

At 403, a density compensation coefficient is calculated, as discussed previously.

At 404, a density compensation coefficient is combined with the biphasic flow density measured at 401 to obtain a compensated biphasic flow density, as previously discussed.

At 405, the estimated drive power is determined. To predict the estimated drive power, a compensated two-phase flow density is used. The estimated drive power Y can be created using the compensated density of the two-phase flow and in accordance with the following equation:

, ρ_comp - компенсированная плотность, и ρ_е - плотность увлеченной фазы.where x is the compensated volume fraction of gas,

, ρ _comp is the compensated density, and ρ _e is the density of the entrained phase.

Figure 5 is a graph of the dependence of the drive power on the volume fraction of gas obtained experimentally for many parameters of the fluid and in the range of volume fractions. The graph reflects the above equation (3). A graph / equation can be used to obtain the estimated drive power based on compensation that has already been performed. The lower lines on the graph are curves of the actual calculated drive power for several sizes of smaller gas bubbles, and the upper lines for several sizes of larger gas bubbles. From the graph it can be seen that larger gas bubbles require more drive power with the same proportion of gas voids. It can also be seen from the graph that for a specific model of a flow meter, an experimental power curve can be obtained experimentally. The characteristic curve can be used to obtain the estimated drive power using the gas volume fraction obtained from the previous density compensation process.

. Таким образом, уравнение (3) позволяет получить предполагаемую мощность Y привода, используя коэффициент компенсации плотности в форме компенсированной объемной доли. В дополнение к этому предполагаемую мощность привода получают, используя показатель мощности вибрационного измерителя плотности (т.е. постоянные С3-С6). Показатель мощности может храниться в измерительной электронике или может быть предоставлен извне. Может потребоваться определить показатель мощности независимым путем для каждой модели вибрационного измерителя расхода.The estimated drive power (Y in the graph) can be obtained using equation (3) by substituting the value of the compensated volume fraction VF _compensated (x in the graph). The compensated volume fraction may contain a volume fraction of either a gas phase or a solid phase with respect to the liquid phase. The compensated volume fraction of VF _compensated is presented as

. Thus, equation (3) allows to obtain the estimated drive power Y using the density compensation coefficient in the form of a compensated volume fraction. In addition, the estimated drive power is obtained using a power indicator of a vibratory density meter (i.e., C3-C6 constants). The power meter may be stored in the meter electronics or may be provided externally. You may need to determine the power metric independently for each model of vibratory flow meter.

Referring again to FIG. 4, at step 406, the estimated drive power is compared with the estimated drive power. This is done in order to determine the accuracy of the flow measurements. If the calculated drive power is within a predetermined deviation for the estimated drive power, then we can assume that the flow measurements have an acceptable level of accuracy. If not, an alarm message may be generated.

A state with large entrained gas bubbles and low flow rates is subject to separation errors, but also to other errors. This condition is called flow asymmetry and is the result of the reaction of bubbles to gravity. If the rate of rise of the bubbles relative to the liquid is comparable to the speed of the liquid, then the gas slows down and accumulates in any zone of the tube with the flow downward and accelerates passing through any zone of the tube with the flow downward. This asymmetry in the distribution of gas leads to a non-representative volume fraction of gas in the meter and further leads to excessive damping of the tube in areas with downward flow. As a result, one cannot expect that the separation compensation in these states will eliminate the flow and density errors, and these states must be identified either to display a warning or for additional compensation.

For states with very small bubbles and higher flow rates, the error due to flow asymmetry is reduced, since small bubbles tend to carry with the fluid (high braking to buoyancy ratio). Ideally, this type of bubble can be identified in order to compensate differently.

A similar state of flow asymmetry exists for suspensions. Large particles and low flow rates cause particles to settle at the bottom of the meter. This causes a non-representative volume fraction of solids in the meter, excessive damping and flow and density errors that cannot be compensated. This asymmetry state also needs to be identified and a warning must be issued.

At step 407, if the calculated drive power is within a predetermined deviation for the estimated drive power, then the compensated density measurement is considered accurate and no further compensation is performed. Otherwise, the flow measurements become unacceptably inaccurate. As a result, when the method is executed, the transition to step 408 occurs.

At step 408, if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, then the method proceeds to step 410.

6 is a graph illustrating the dependence of the calculated drive power and the estimated drive power on the volume fraction of the entrained phase. 6, the design power of the drive is shown to exceed the estimated power of the drive. The estimated drive power is the power required for the nominal size of the submerged bubbles, fluid viscosity, and other parameters such as flow rate. The density compensation coefficient is likewise determined for the nominal parameters of the fluid mixture. Therefore, if the calculated drive power differs from the estimated drive power, then the compensated density differs from the true density of the two-phase mixture. For example, in states with a large bubble size and low viscosity, the power consumption is greater than the estimated power, and, in addition, there is a higher level of error compared to that which corrects the compensation coefficient. There is a correlation between power and density error, since the density error arises from the same phenomenon, due to which the energy of vibration is dissipated, namely the separation of the liquid. Thus, the difference between the estimated power and the rated power serves to verify the accuracy of the compensation. In this example, the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value (dashed line). Therefore, measurements of compensated density can be considered unacceptably inaccurate. If this happens, an alarm message may be triggered indicating that it is necessary to change the flow conditions, for example by mixing the flow or increasing the flow or pressure. In addition, up to the upper limit value, the equation of the compensation coefficient can be changed for a state with higher separation.

Fig.7 is a graph of the estimated drive power and the estimated drive power, similar to Fig.6, except that the estimated drive power is shown to have a lower value compared to the estimated drive power. This condition occurs when the degree of separation of the fluid is less than under the nominal conditions used to determine the estimated power. In this example, the calculated drive power is less than the expected power by more than a predetermined lower limit value (dashed line). Thus, the compensated density of the two-phase flow is not yet sufficiently accurate. Therefore, the equation of the compensation coefficient can be refined so that it reflects a lower degree of separation. The modified compensation coefficient allows a more accurate compensated density of the two-phase flow to be obtained and leads to a closer follow of the calculated drive power over the estimated drive power.

If you again refer to figure 4, at step 409, if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, an alarm message is generated. An alarm message can be generated to alert the operator of adverse flow conditions. An alarm message can be created to warn that flow measurements have become unreliable. An alarm message can be created to warn of an excessive level of entrained phase, for example, an excessive solids content or an excessive particle size of a solid substance, or an excessive size of bubbles in the case of entrained gas. In addition to this, an alarm message can be created to request a change in flow conditions. For example, an alarm message may request a change in flow rate, flow pressure, or other flow parameters. In some embodiments of the present invention, an alarm state may be maintained and / or transmitted, for example, transmitted to an operator or technician who can change flow conditions.

At step 410, if the calculated drive power is less than the estimated drive power, the compensated two-phase flow density can be refined to improve the accuracy and reliability of flow measurements. In some embodiments of the present invention, the compensated biphasic flow density is refined by decreasing the density compensation coefficient. In some embodiments of the present invention, the density compensation coefficient is reduced by a value proportional to the difference between the calculated drive power and the predetermined lower limit value.

Claims (46)

1. A vibration meter (5) for the flow rate of a two-phase material flow including a entrained phase, configured to correct the density of the flowing two-phase flow, comprising a flow meter assembly (10) including a drive (104), wherein the flow meter assembly (10) is made with the ability to create a vibrational reaction for the flowing material and additionally contains measuring electronics (20) connected to the node (10) of the flow meter and receiving a vibrational reaction, a vibration meter (5) of flow, distinguish which:
measuring electronics (20) is configured to measure the density of a two-phase flow by receiving vibrational signals from the flowmeter meter assembly (10), determine the calculated drive power required by the drive (104) of the flow meter assembly, and calculate a density compensation coefficient using liquid density the liquid component of the two-phase flow, the density of the entrained phase being the entrained component, the measured density of the two-phase flow, and the rated drive power. 2. The vibratory flow meter (5) according to claim 1, in which the measuring electronics (20) is configured to multiply the drive voltage by the drive current to determine the design power of the drive. 3. The vibratory flow meter (5) according to claim 1, in which the measuring electronics (20) is configured to multiply the voltage of the sensor for measuring mechanical displacements by the current of the drive in order to determine the design power of the drive. 4. Vibratory flow meter (5) according to claim 1, in which the measuring electronics (20) is configured to solve the equation

to determine the design power of the drive, where K is the constant of proportionality; I _d is the measured drive current; I ₀ - drive current for a fraction with zero volume; E _PO is the voltage of the sensor for measuring mechanical displacements and E _t is the planned voltage of the sensor for measuring mechanical displacements. 5. The vibration meter (5) flow rate according to claim 1, in which the calculation of the coefficient of density compensation contains a solution to the equation

and ρ ₁ is the density of the liquid; ρ _e is the density of the entrained phase; ρ _uut is the measured density of the two-phase flow; P _computed is the calculated drive power, and the terms C1 and C2 contain predetermined constants depending on the meter. 6. The vibratory flow meter (5) of claim 1, wherein the measuring electronics (20) is further configured to combine the density compensation coefficient with the measured density of the two-phase flow to provide a compensated density of the two-phase flow. 7. The vibratory flow meter (5) of claim 1, wherein the measuring electronics (20) is further configured to combine the density compensation coefficient with the measured density of the two-phase flow to provide a compensated density of the two-phase flow, determine the estimated drive power using the liquid density, the density of the entrained phase, the compensated density of the two-phase flow and the power indicator of the vibrating flow meter (5), and also to determine the accuracy of the flow measurements performed by a vibratory flow meter (5), based on the difference between the estimated drive power and the calculated drive power. 8. The vibratory flow meter (5) of claim 7, wherein the measuring electronics (20) is further configured to solve the equation

,
where ρ _comp is the compensated density of the two-phase flow to obtain a compensated volume fraction for the two-phase flow. 9. The vibrational flow meter (5) of claim 7, wherein determining the accuracy further comprises creating an alarm message if the calculated drive power differs from the estimated drive power by more than a predetermined deviation. 10. The vibratory flow meter (5) of claim 7, wherein determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of entrained phase and further indicating the need to change flow conditions in a vibratory flow meter. 11. The vibratory flow meter (5) of claim 7, wherein determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating excessive gas bubble size and further indicating the need to change flow conditions in a vibratory flow meter. 12. The vibratory flow meter (5) of claim 7, wherein determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of solid entrainment phase and further indicating on the need to change flow conditions in a vibratory flow meter. 13. The vibratory flow meter (5) of claim 7, wherein determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value. 14. The vibrational flow meter (5) of claim 7, wherein determining the accuracy further comprises clarifying the compensated density of the two-phase flow if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value or if the calculated drive power exceeds the estimated drive power more than a predetermined upper limit value. 15. The vibrational flow meter (5) of claim 14, wherein the refinement of the compensated density of the two-phase flow comprises a decrease in the density compensation coefficient by a value proportional to the difference between the calculated drive power and a predetermined lower limit value. 16. The vibratory flow meter (5) of claim 7, wherein determining the accuracy further comprises comparing the estimated drive power with the estimated drive power, generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, and refinement of the compensated density of a two-phase flow by reducing the density compensation coefficient by an amount proportional to the difference between the calculated drive power and the predetermined defined lower limit value, if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value. 17. A method for correcting the density of a two-phase flow of material flowing in a vibration meter, including a entrained phase, comprising measuring the density of a two-phase flow, characterized in that it comprises the following steps:
determine the calculated drive power required by the drive, which is part of the flow meter assembly; and
a density compensation coefficient is calculated using the density of the liquid being the liquid component of the two-phase flow, the density of the entrained phase being the entrained component, the measured density of the two-phase flow, and the rated drive power. 18. The method according to 17, in which the step of determining the design power of the drive comprises multiplying the voltage of the drive by the current of the drive. 19. The method according to 17, in which the step of determining the design power of the drive comprises multiplying the voltage of the sensor for measuring mechanical displacements by the current of the drive. 20. The method according to 17, in which the step of determining the design power of the drive contains a solution to the equation

where K is the constant of proportionality; I _d is the measured drive current; I ₀ - drive current for a fraction with zero volume; E _PO is the voltage of the sensor for measuring mechanical displacements and E _t is the planned voltage of the sensor for measuring mechanical displacements. 21. The method according to 17, in which the step of calculating the density compensation coefficient contains a solution to the equation

moreover, ρ ₁ is the density of the liquid, ρ _uut is the measured density of the two-phase flow, ρ _e is the density of the entrained phase, P _computed is the calculated drive power, and elements C1 and C2 contain predetermined constants depending on the meter. 22. The method of claim 17, further comprising combining a density compensation coefficient with a measured two-phase flow density to provide a compensated two-phase flow density. 23. The method according to 17, further comprising the following steps:
combining a density compensation coefficient with a measured biphasic flow density to provide a compensated biphasic flow density;
determine the estimated drive power using the density of the liquid, the density of the entrained phase, the compensated density of the two-phase flow and the power indicator of the vibratory flow meter; and
determining the accuracy of the flow measurements made by the vibratory flow meter based on the difference between the estimated drive power and the calculated drive power. 24. The method according to item 23, further comprising the step of solving the equation

,
where ρ _comp is the compensated density of the two-phase flow to obtain a compensated volume fraction for the two-phase flow. 25. The method according to item 23, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power differs from the estimated drive power by more than a predetermined deviation. 26. The method according to item 23, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of entrained phase and further indicating the need to change the flow conditions in a vibratory flow meter. 27. The method according to item 23, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive size of gas bubbles and further indicating the need to change the flow conditions in a vibratory flow meter. 28. The method according to item 23, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of solid entrainment phase and further indicating the need to change conditions flow in a vibratory flow meter. 29. The method according to item 23, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value. 30. The method according to item 23, in which the step of determining the accuracy further comprises clarifying the compensated density of the two-phase flow if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value or if the estimated drive power exceeds the estimated drive power by more than a predetermined defined upper limit value. 31. The method according to clause 30, in which the refinement of the compensated density of the two-phase flow comprises reducing the density compensation coefficient by an amount proportional to the difference between the calculated drive power and a predetermined lower limit value. 32. The method according to item 23, in which the step of determining the accuracy further comprises the following:
compare the estimated drive power with the estimated drive power;
create an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value; and
specify the compensated density of the two-phase flow by reducing the density compensation coefficient by an amount proportional to the difference between the calculated drive power and a predetermined lower limit value if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value. 33. The method of density correction when measuring with a vibration meter the flow rate of a two-phase flow of material flowing through the specified meter, which includes an entrained phase, containing a density measurement of a two-phase flow, characterized in that it comprises the following steps:
determine the calculated drive power required by the drive, which is part of the flow meter assembly;
calculating a density compensation coefficient using the density of the liquid being the liquid component of the two-phase flow, the density of the entrained phase being the entrained component, the measured density of the two-phase flow, and the estimated drive power;
combining a density compensation coefficient with a measured biphasic flow density to provide a compensated biphasic flow density;
determine the estimated drive power using the density of the liquid, the density of the entrained phase, the compensated density of the two-phase flow and the power indicator of the vibratory flow meter; and
determine the accuracy of the flow measurements by the vibratory flow meter based on the difference between the value of the estimated drive power and the calculated drive power. 34. The method according to p, in which the step of determining the design power of the drive includes multiplying the voltage of the drive by the current of the drive. 35. The method according to p, in which the step of determining the design power of the drive includes multiplying the voltage of the sensor to measure mechanical displacements by the current of the drive. 36. The method according to p, in which the step of determining the design power of the drive contains a solution to the equation

where K is the constant of proportionality; I _d is the measured drive current; I ₀ - drive current for a fraction with zero volume; E _PO is the voltage of the sensor for measuring mechanical displacements and E _t is the planned voltage of the sensor for measuring mechanical displacements. 37. The method of claim 33, wherein the step of calculating the density compensation coefficient comprises solving the equation

and ρ ₁ is the density of the liquid; ρ _e is the density of the entrained phase; ρ _uut is the measured density of the two-phase flow; P _computed is the calculated drive power, and elements C1 and C2 contain predetermined constants that depend on the meter. 38. The method according to clause 33, further comprising the step of solving the equation

,
where ρ _comp is the compensated density of the two-phase flow to obtain a compensated volume fraction for the two-phase flow. 39. The method according to p, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power differs from the estimated drive power by more than a predetermined deviation. 40. The method according to claim 33, wherein the step of determining the accuracy further comprises generating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of entrained phase and further indicating the need to change the flow conditions in a vibratory flow meter. 41. The method according to clause 33, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating the excessive size of the gas bubbles and further indicating the need to change the flow conditions in a vibratory flow meter. 42. The method according to clause 33, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value, indicating an excessive level of solid entrainment phase and additionally indicating the need to change conditions flow in a vibratory flow meter. 43. The method according to clause 33, in which the step of determining the accuracy further comprises creating an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value. 44. The method according to claim 33, wherein the step of determining the accuracy further comprises clarifying the compensated density of the two-phase flow if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value or if the estimated drive power exceeds the estimated drive power by more than a predetermined defined upper limit value. 45. The method according to item 44, in which the refinement of the compensated density of the two-phase flow comprises reducing the density compensation coefficient by an amount proportional to the difference between the calculated drive power and a predetermined lower limit value. 46. The method according to p, in which the step of determining the accuracy further comprises the following:
create an alarm message if the calculated drive power exceeds the estimated drive power by more than a predetermined upper limit value; and
specify the compensated density of the two-phase flow by reducing the density compensation coefficient by a value proportional to the difference between the calculated drive power and a predetermined lower limit value if the calculated drive power is less than the estimated drive power by more than a predetermined lower limit value.

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