CN1934425A - Coriolis mass flowmeter - Google Patents

Abstract

The invention relates to a Coriolis mass flowmeter comprising a vibration-type measuring sensor (1) comprising at least one measuring tube (10) through which a medium can flow during operation. During operation, the measuring tube moves by mechanical vibrations, especially bending vibrations, by means of an exciter arrangement (40). The Coriolis mass flowmeter also comprises a sensor arrangement (50) for generating vibration measuring signals (sl, s2) representing inlet-side and outlet-side vibrations of the measuring tube (10). Flowmeter electronics (2) controlling the exciter arrangement generate an intermediate value (X'm) which is derived from the vibration measuring signals (s1, s2) and represents an uncorrected mass flow, and an exciter current (iexc) driving the exciter arrangement. An intermediate value (X2) is derived from the exciter current and/or from part of the exciter current (iexc), said value corresponding to a dampening of the vibrations of the measuring tube (11), dependent on an apparent viscosity and/or a viscosity-density product of the medium guided in the measuring tube (11). Furthermore, a correction value (XK) for the intermediate value (X'm) is generated using the intermediate value (X2) and a viscosity measuring value (Xeta) that is determined previously or during operation and corresponds to a viscosity of the medium guided in the measuring tube and/or a pre-determined reference viscosity. On the basis of the intermediate value (X'm) and the correction value (XK), the flowmeter electronics can then generate an accurate mass flow measuring value (Xm).

Description

Coriolis mass flowmeter

Technical field

The present invention relates to a kind of Coriolis-type mass flowmeter/densimeter, it is used for particularly two-phase or multiphase medium that pipeline flows, and the invention still further relates to a kind of method that is used to produce the measured value of representation quality flow.

Background technology

In process measurement and automatic technology, physical parameter for medium mobile in the measuring channel, mass rate for example, density and/or viscosity, often use particularly Coriolis mass flowmeter of this on-line measurement instrument, it utilizes in the pipeline that inserts boot media and produces reacting force by the vibration-type measuring transducer of MEDIA FLOW warp and coupled measurement and function circuit in medium in operation, for example corresponding to the Coriolis force of mass rate, corresponding to the inertial force of density or corresponding to friction force of viscosity etc., measurement instrument obtains representing the mass rate of medium from these power, one or more measuring-signals of viscosity and/or density.This on-line measurement instrument has the oscillating mode transmitter, and their mode of operation is well known by persons skilled in the art and detailed description: WO-A 03/095950 is for example arranged in following document, WO-A03/095949, WO-A 03/076880, WO-A 02/37063, WO-A 01/33174, WO-A00/57141, WO-A 99/39164, WO-A 98/07009, WO-A 95/16897, WO-A88/03261, US 2003/0208325, US-B 66 91 583, US-B 66 51 513, US-B65 13 393, US-B 65 05 519, US-A 60 06 609, US-A 58 69 770, US-A 5,796 011, US-A 56 02 346, US-A 56 02 345, US-A 55 31 126, US-A 53 01557, US-A 52 53 533, US-A 52 18 873, US-A 50 69 074, US-A 48 76 898, US-A 47 33 569, US-A 46 60 421, US-A 45 24 610, US-A 44 91 025, US-A 41 87 721, EP-A 1 281 938, EP-A 1 001 254 or EP-A 553 939.

For boot media, measuring transducer generally includes at least one measuring tube, and it for example is contained in tubulose or the box-like supporting frame.Measuring tube has bending or straight pipeline section, makes this pipeline section vibration by the motor exciting bank during operation, to produce above-mentioned reacting force.In order to detect the particularly pipeline section vibration of entrance side and outlet side, measuring transducer also has the electric physical sensing apparatus that the motion of pipeline section is reacted to some extent.In the situation of the Coriolis mass flowmeter that is used for the medium that pipeline flows, the measurement of mass rate for example is achieved in that and allows in inserting pipeline and the in operation measuring tube of vibration of MEDIA FLOW, thereby medium is subjected to Coriolis force.This makes the entrance side of measuring tube and outlet side zone vibrate on phase shift ground each other.Phase shift size measuring as mass rate.Therefore, the vibration of measuring tube is utilized the length along measuring tube of sensor as aforementioned device two osciducers separated from one another and detects and be converted into the oscillation measurement signal, by they each other phase shift and draw mass rate.

Above-mentioned US-A 41 87 721 has mentioned, and the instantaneous density of flow media also can utilize Coriolis mass flowmeter to measure usually, and in fact based on the frequency of at least one the oscillation measurement signal that sends by sensor device.In addition, the temperature of medium is also directly measured with suitable manner usually, for example utilizes the temperature sensor that is arranged on the measuring tube.Except the mass rate and/or the density of medium, it is long-pending that the on-line measurement instrument that Coriolis mass flowmeter or other have an oscillating mode transmitter also can be used for measuring the viscosity and/or the viscosity-density of the medium that flows at measuring tube; About this point, especially referring to US-B 66 51 513, US-A 55 31 126, US-A 52 53 533 and US-A 45 24 610 or WO-A 95/16897.So can suppose, in any situation, modern on-line measurement instrument with vibration-type measuring transducer, density, viscosity and/or the temperature that Coriolis mass flowmeter can also measuring media particularly considered particularly that these are measured and can be used for compensation when mass flow measurement usually because the measuring error that Media density that fluctuates and/or dielectric viscosity cause; About this point, especially referring to US-B 65 13 393, US-A 60 06 609, US-A 56 02 346, WO-A 02/37063, WO-A 99/39164 or WO-A 00/36379.

Yet, have been found that vibration-type measuring transducer in described type (JP-A10-281846 for example, WO-A 03/076880 or US-B 65 05 519) use in, in the situation of nonhomogeneous media, particularly in the situation of two-phase or multiphase medium, the oscillation measurement signal that obtains from the vibration of measuring tube particularly also has described phase shift all to be subjected to considerable fluctuation, although separately the viscosity of medium phase and density and mass rate are actually constant and/or obtained suitable consideration, thereby if there is not remedial measures then these signals will can not be used to measure the physical parameter of expectation fully.This nonhomogeneous media can be a liquid for example, and the gas that exists in the pipeline in the situation of feed or filling process particularly air is introduced into wherein inevitably, perhaps Rong Xie medium for example carbon dioxide from this liquid, discharge and bubble.Moist or saturated steam is another example of this nonhomogeneous media.The reason of the problem that occurs when utilizing vibration-type measuring transducer to measure nonhomogeneous media, for example mention bubble or solid particle and so-called " bubble effect " of inner one-sided that adhere to or deposition on the measuring tube tube wall, the bubble of wherein carrying secretly is as the liquid of the liquid partial volume that is transverse to the accumulation of the measuring tube longitudinal axis.

Although the mobile or medium that had proposed in WO-A 03/076880 before actual flow is measured is regulated to reduce the measuring error relevant with two-phase or multiphase medium, but for example JP-A10-281846 and US-B 65 05 519 have put down in writing and have analyzed the real medium density of accurately measuring and utilize poor between the apparent Media density that Coriolis mass flowmeter determines during operation, proofread and correct oscillation measurement signal related flow measurement, particularly mass flow measurement.

Especially, advised the pre-training of oscillation measurement signal, sometimes or even adaptive sorter for this reason.Sorter can be configured to the form of for example Kohonen mapping or neural network, and the several parameters that can measure based on operating period is mass rate and density and other characteristic of obtaining thus particularly, perhaps comprise the interval of the oscillation measurement signal of one or more oscillation period, carry out correction by use.Use this sorter to compare with existing coriolis mass flowmeters/densitometer, for example have measuring transducer almost be need not the advantage that changes, here, change the function circuit that relates to physical construction, exciting bank or drive it, they all mate application-specific especially.Yet a remarkable shortcoming of this sorter is, compares with existing coriolis mass flowmeters, needs sizable change in the zone that produces measured value, especially analog to digital converter of Shi Yonging and microprocessor.In fact, as disclosed in US-B 65 05519, for example in the digitizing of the oscillation measurement signal of about 80Hz oscillation frequency, the sort signal analysis need about 55kHz or higher sampling rate, to reach enough precision.In other words, must use the sampling rate sampling oscillation measurement signal that is far longer than 600: 1.In addition, the firmware of storage and execution correspondingly becomes complicated in the digital measurement circuit.Another shortcoming of this sorter is, for measuring transducer in esse measuring condition of operating period, characteristic or other factor that influences measuring accuracy that must train and correspondingly confirm particularly to change usually for installation site, testing medium and its.Because the interactive high complexity of all of these factors taken together, training and affirmation thereof can only onlinely be carried out and carry out separately for each measuring transducer usually, and this causes that measuring transducer starts cost and raises.In addition, have been found that, but this sorting algorithm is on the one hand because the high complexity suitable physical mathematics model of relevant or comprehension parameter because common imprecise existence possesses skills on the other hand, so sorter has very low transparency and thereby often is difficult to be communicated with.Certainly, what be associated therewith is, in client's part considerable reservation can be arranged, and when the sorter that uses is adaptive, when for example being neural network, this acceptance problem occurs in client's part especially.

As avoid the problem relevant with nonhomogeneous media another may, for example US-A 4,524 610 proposes to install and measure transmitter like this, makes straight measuring tube extend substantially vertically, with heteropical precipitation of the particularly gaseous state that prevents this interference.Yet this is a very special solution, and it can only realize in the condition of limited very much, particularly in the measuring technique in industrial process.On the one hand, in this situation, measuring transducer to be fit into wherein pipeline may must be fixed to transmitter rather than conversely, this means that the user need increase extra cost in creating the measuring position.On the other hand, as already mentioned, measuring tube may be crooked, thereby can not deal with problems by changing the orientation of installing.About this point, have been found that deterioration by the measuring-signal that uses vertically arranged straight measuring tube in fact not avoid significantly to be mentioned.

Summary of the invention

An object of the present invention is to provide a kind of corresponding Coriolis mass flowmeter, it is suitable for even particularly very accurately measures mass rate under the situation of two-phase or multiphase medium at nonhomogeneous media, and it in fact preferably has with respect to the actual mass flow less than 10% measuring error.Another purpose provides a kind of corresponding method, is used to obtain corresponding mass flow measurement.

In order to reach this purpose, the invention provides a kind of Coriolis mass flowmeter, Coriolis mass flow/density measuring instrument or Coriolis mass and flow/viscosity measurement instrument particularly, be used for the particularly mass rate of two-phase or multiphase medium of the mobile medium of measuring channel, this Coriolis mass flowmeter involving vibrations type measuring transducer and with the measurement instrument electron device of this measuring transducer electric coupling

-wherein measuring transducer has:

--at least one measuring tube, it inserts pipeline, particularly basic for straight and be used to guide testing medium, this measuring tube to communicate with the pipeline that is connected,

--exciting bank, act on and be used to make the vibration of at least one measuring tube on the measuring tube, it makes measuring tube during operation at least discontinuously and/or crooked at least in part vibration, and

--sensor device, be used to detect the vibration of at least one measuring tube, it sends at least one first oscillation measurement signal of representing the vibration of measuring tube entrance side and at least one represents the second oscillation measurement signal of measuring tube outlet side vibration, and

-measurement instrument electron device wherein

--send the exciting current that drives exciting bank at least discontinuously, and send the mass flow measurement of representative mass rate to be measured at least discontinuously,

--generate first intermediate value and second intermediate value, wherein first intermediate value obtains and corresponding to mass rate to be measured and/or two vibration survey phase difference between signals from the oscillation measurement signal, second intermediate value obtains and corresponding to the decay of the vibration of measuring tube from the one-component of exciting current and/or exciting current, this decay depends on the apparent viscosity of the medium that guides in the measuring tube especially and/or viscosity-density is long-pending, and

--use second intermediate value and viscosity measurement value, obtain obtaining mass flow measurement for the corrected value of first intermediate value and based on first intermediate value and corrected value, wherein viscosity measurement value is in advance or during operation particularly by using that measuring transducer and/or measurement instrument electron device are determined and corresponding to the viscosity of the medium that guides in measuring tube and/or corresponding to the reference viscosity that before provided.

In addition, the invention reside in a kind of method, it uses the mass rate of particularly two-phase or multiphase medium that flows in the Coriolis mass flowmeter measuring channel, this Coriolis mass flowmeter have vibration-type measuring transducer and with the measurement instrument electron device of measuring transducer electric coupling, this method may further comprise the steps:

-make flow through at least one measuring tube that communicates with pipeline of measuring transducer of testing medium, and exciting current is fed into exciting bank with the measuring tube mechanical couplings of boot media, to make the measuring tube mechanical oscillation, particularly crooked vibration,

-make measuring tube vibrate with the mode of oscillation that produces Coriolis force in the medium that is suitable for flowing through therein,

-detect the vibration of measuring tube and obtain representing the first oscillation measurement signal of entrance side vibration and the second oscillation measurement signal of representing outlet side to vibrate,

-use two oscillation measurement signals, obtain first intermediate value, it is corresponding to mass rate to be measured and/or two oscillation measurement phase difference between signals,

-determine second intermediate value, it is derived from exciting current and corresponding to the decay of the vibration of measuring tube, and it is long-pending that this decay depends on the apparent viscosity and/or the viscosity-density of the medium that guides in the measuring tube,

-viscosity measurement the value utilizing second intermediate value and determine before, obtain the corrected value of first intermediate value, described viscosity measurement value is particularly definite and corresponding to the viscosity of the medium that guides in the measuring tube by using measuring transducer and/or measurement instrument electron device, and

-utilize corrected value to proofread and correct first intermediate value, and obtain representing the mass flow measurement of mass rate to be measured.

In first development of Coriolis mass flowmeter of the present invention, corrected value is represented the deviation between the apparent viscosity of the medium that guides in the viscosity of medium and the measuring tube and/or viscosity-density long-pending, wherein apparent viscosity is to determine based on the one-component of exciting current and/or exciting current during operation, and the amassing of viscosity-density is to determine based on exciting current during operation.

In second development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device is determined corrected value based on the comparison of second intermediate value and viscosity measurement value and/or poor based on what exist between second intermediate value and viscosity measurement value.

In the 3rd development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device also uses at least one oscillation measurement signal to obtain second intermediate value.

In the 4th development of Coriolis mass flowmeter of the present invention, exciting bank makes measuring tube carry out torsional oscillation during operation at least discontinuously and/or at least in part, particularly with bending vibration alternately or be superimposed upon torsional oscillation in the crooked vibration in time, this torsional oscillation centers on the measuring tube longitudinal axis that aligns substantially with measuring tube, the principal axis of inertia of measuring tube particularly, and the measurement instrument electron device also based on the exciting current that drives exciting bank and/or based on the one-component of exciting current, is determined the viscosity measurement value.

In the 5th development of Coriolis mass flowmeter of the present invention, carry out torsional oscillation by the measuring tube that exciting bank drives, measuring tube torsional oscillation frequency is different with measuring tube swaying frequency, carries out the particularly crooked vibration of swaying by the measuring tube that exciting bank drives with this swaying frequency.

In the 6th development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device also obtains the viscosity measurement value.

In the 7th development of Coriolis mass flowmeter of the present invention,

-measurement instrument electron device sends density measurement, this density measurement from the first and/or second vibration survey signal obtain and represent density of medium and

-measurement electron device is also determined corrected value based on density measurement, particularly viscosity measurement value.

In the 8th development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device is coupled to outside viscosity measurement instrument, particularly be positioned at Coriolis mass flowmeter viscosity measurement instrument at a distance, and the viscosity measurement instrument sends the viscosity measurement value at least discontinuously.

In the 9th development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device is coupled with differential pressure pick-up at least discontinuously, and this differential pressure pick-up sends the differential pressure measurement value of representative along the pressure differential of duct survey at least discontinuously.

In the tenth development of Coriolis mass flowmeter of the present invention, the measurement instrument electron device is based on exciting current and/or based on the one-component of exciting current and utilize the viscosity measurement value to determine concentration measurement at least discontinuously, the particularly relative volume and/or the quality ratio of a medium phase in the situation of two-phase or multiphase medium of this concentration measurement representative in measuring tube.

In the 11 development of Coriolis mass flowmeter of the present invention, measuring tube communicates by inlet pipeline section and outlet pipe section with the pipeline that is connected, the pipeline section that wherein enters the mouth feeds inlet end, outlet pipe section feeds endpiece (12#), and measuring transducer be included in the inlet end of measuring tube and endpiece fixing particularly with the antihunter of exciting bank mechanical couplings, it particularly vibrates with measuring tube during operation at least discontinuously anti-phasely.

In the 12 development of Coriolis mass flowmeter of the present invention, Coriolis mass flowmeter is used for measuring the mass rate of two-phase or multiphase medium, particularly liquid-gas mixture of flowing at pipeline.

In first development of method of the present invention, this method further comprises step: make the crooked vibration of measuring tube, to produce Coriolis force in the medium of flowing through wherein.

In second development of method of the present invention, this method further comprises step: make the measuring tube torsional oscillation, particularly be superimposed upon the torsional oscillation on the crooked vibration; And consider the exciting current and/or the component that makes the measuring tube torsional oscillation of exciting current at least, determine second intermediate value.

In the 3rd development of method of the present invention, the step that obtains the corrected value of intermediate value further comprises step: with second intermediate value and viscosity measurement value relatively, and/or poor between definite second intermediate value and the viscosity measurement value; And the deviation of the apparent viscosity of the medium that guides in the viscosity of definite medium and the measuring tube of determining based on exciting current during operation, and/or the long-pending deviation of the viscosity-density of the medium that guides in the viscosity of definite medium and the measuring tube of determining based on exciting current during operation.

In the 4th development of method of the present invention, this method further comprises step: second measured value that obtains representing Media density based on the oscillation measurement signal; And use second measured value to obtain corrected value.

In the 5th development of method of the present invention, this method is used to the vibration-type measuring transducer calibrating Coriolis mass flowmeter and/or have at least one measuring tube.

The present invention is to recognize especially, and the excitation electric energy that is used for keeping the measuring tube swaying that is fed into measuring transducer can be subjected to the heterogeneity influence of testing medium, and heterogeneity for example is to mix the bubble deposited, solid particle etc.If with this long-pending excitation electric energy that depends on the apparent viscosity of the medium that guides in the measuring tube and/or viscosity-density with actual or for example measure the dielectric viscosity of at least more accurately measuring that obtains relatively by corresponding outside and/or internal reference, then can be with enough precision about estimation of the heterogeneity in the medium and the instantaneous relevant part of mass flow measurement.Special advantage of the present invention is, even the reference measure of viscosity also can utilize identical Coriolis mass flowmeter and be independent of possible externally measured position and carry out.

Another advantage of the present invention is, in the situation of Coriolis mass flowmeter of the present invention, compare with existing instrument, only in general generation digital measured value, need less change, basically be limited to firmware, and aspect measuring transducer and generation and pre-service oscillation measurement signal, do not need or only need small change.So for example the oscillation measurement signal can be as in the past, with well below 100: 1, particularly about 10: 1 sampling rate is sampled.

Description of drawings

Now the embodiment that provides in reference to the accompanying drawings explains the present invention in detail and has further developing of advantage.Use identical Reference numeral for identical parts in institute's drawings attached; For clearly needing, in the accompanying drawing of back, omitted already mentioned Reference numeral.

Fig. 1 has shown Coriolis mass flowmeter, and it can insert in the pipeline, is used for the mass rate of the mobile fluid of measuring channel,

Fig. 2 has shown the embodiment of the vibration-type measuring transducer of the measurement instrument that is applicable to Fig. 1 with perspective side elevation view,

Fig. 3 has shown the measuring transducer of Fig. 2 with side view,

Fig. 4 has shown the measuring transducer of Fig. 2 with first cross section,

Fig. 5 has shown the measuring transducer of Fig. 2 with second cross section,

Fig. 6 has shown the longitudinal cross-section side view of another embodiment of the vibration-type measuring transducer of the Coriolis mass flowmeter that is applicable to Fig. 1,

Fig. 7 schematically illustrate with the form of block diagram Fig. 1 Coriolis mass flowmeter the measurement instrument electron device advantageous development and

Fig. 8, the 9th utilizes the chart of the measurement data that the Coriolis mass flowmeter experiment of Fig. 1-7 determines.

Embodiment

Fig. 1 is the skeleton view of Coriolis mass flowmeter 1, and this measurement instrument is used for detecting the mass rate m of the medium that the pipeline (not shown) flows and with its mass flow measurement X with instantaneous this mass rate of representative _mForm performance.Medium can be actually any flowable materials, for example liquid, gas, steam etc.In addition, Coriolis mass flowmeter 1 can also be used for the density p and/or the viscosities il of measuring media.

For this reason, Coriolis mass flowmeter 1 involving vibrations type measuring transducer 10 and measurement instrument electron device 50, testing medium this vibration-type measuring transducer 10 of flowing through during operation, measurement instrument electron device 50 is electrically connected with measuring transducer 10.Fig. 2-6 has shown the embodiment and the development of transmitter, and Fig. 7 is the illustrative example of measurement instrument electron device.Preferably, measurement instrument electron device 50 is further designed like this, makes it to measure and/or other service data via data transmission system (for example field bus system) and upper measured value processing unit (for example programmable logic controller (PLC) (PLC), personal computer and/or workstation) exchange.In addition, design measurement instrument electron device 50 like this, make that it can be by external power source for example by above-mentioned field bus system power supply.Be coupled to the situation of fieldbus or other communication system for the vibration-type measuring instrument, measurement instrument electron device 50, particularly programmable measurement instrument electron device has the communication interface that is used for data communication accordingly, for example is used for measurement data is sent to programmable logic controller (PLC) above-mentioned or upper Process Control System.In order to regulate measurement instrument electron device 50, electric-device housing 200 also is provided, it particularly is directly installed on the measuring transducer 10 from the outside, perhaps from measuring transducer 10 dismountings.

As already mentioned, measurement instrument involving vibrations type measuring transducer 10, it is flowed through by testing medium during operation, and be used for producing such mechanical reactance at the medium of flowing through, particularly depend on mass rate Coriolis force, depend on the inertial force of Media density and/or depend on the friction force of dielectric viscosity, but these power geodetics particularly can by sensor react on measuring transducer.Based on the reacting force of these characterized medium, can measure for example flow, density and/or the viscosity of medium in mode well known in the art.

Fig. 3 and 4 schematically illustrates the physics-electrical switching device as the embodiment of oscillating mode transmitter 10.The mechanical realization of this conversion equipment and function are well-known to those skilled in the art and for example in US-B 66 91 583, WO-A 03/095949 or WO-A 03/095950 detailed description are arranged.

For boot media and produce described reacting force, but measuring transducer comprises that at least one has the straight substantially measuring tube 10 of scheduled measurement pipe diameter, makes it at least discontinuously with one or more frequency vibrations during operation, thereby repeats elastic deformation.Here, the elastic deformation of measuring tube inner chamber mean the spatial form of measuring tube inner chamber and/or locus with the mode that can be scheduled within the elastic range of measuring tube 10 circularly, periodic variation particularly.About this point, referring to US-A 48 01 897, US-A 56 48 616, US-A 57 96 011, US-A 6,066 609, US-B 66 91 583, WO-A 03/095949 and/or WO-A 03/095950.Although be noted here that measuring transducer only comprises a straight measuring tube in this embodiment, can use a large amount of other Coriolis mass and flow measuring transducers of putting down in writing in the prior art, replace described measuring transducer.Especially, the vibration-type measuring transducer that for example has two parallel straight measuring tubes of being flowed through by testing medium is suitable, and this for example has detailed description in US-A 5,602 345.

Measuring tube 10 communicates with the pipeline of introducing or derivation testing medium at entrance side and outlet side in common mode, and this measuring tube is quilt clamping oscillatorily in the support 14 of the particularly counter-bending of rigidity and distortion.Replace showing here with the axially extending tubular bracket 14 of measuring tube, certainly use other proper supporting part, such as being parallel to pipe or the box like structure that measuring tube distributes.In order to make MEDIA FLOW through wherein, measuring tube 10 by feeding inlet end 11# inlet pipeline section 11 and the outlet pipe section 12 of feeding endpiece 12# be connected with pipeline.Measuring tube 10 and inlet and outlet pipe section 11,12 are in alignment with each other as far as possible and align with virtual measuring tube longitudinal axes L, and preferably are embodied as whole one, thereby for example can use single tubular workpiece to be used for their manufacturing; If desired, measuring tube 10 and pipeline section 11,12 also can link the workpiece manufacturing that for example welds together by what separate afterwards.In order to make measuring tube 10 and inlet and outlet pipe section 11,12, can use the normally used any material of this measuring transducer especially, such as ferroalloy, titanium alloy, zircaloy and/or tantalum alloy, plastics or pottery.For measuring transducer releasably with the situation of pipeline assembling, inlet pipeline section 11 and outlet pipe section 12 preferably have first and second flanges 13,14 separately respectively; Yet if desired, inlet and outlet pipe section 11,12 also can be for example directly link to each other with pipeline by welding or brazing.In addition, as what schematically show, provide converter shell 100 in Fig. 1, it is fixed to inlet and outlet pipe section 11,12 and encirclement measuring tube 10; About this point, please refer to Fig. 1 and 2.

In order to measure mass rate, excitation measuring tube 10 is with first mode of oscillation, it is so-called effective model vibration, wherein it carries out the vibration transverse to the measuring tube longitudinal axes L at least in part, particularly crooked vibration, especially, it is laterally outwardly-bent, basically with the natural torsion eigenfrequency vibration according to the nature first eigen oscillation form.The natural eigenfrequency of this cross mode of known measuring tube also depends on density of medium ρ to a certain extent.

For the ducted medium that connects be flow and thereby the non-vanishing situation of mass rate m, utilize measuring tube 10 in flow media, to cause Coriolis force with the effective model vibration.These power are influential for measuring tube 10, make in mode well-known to those skilled in the art, the additional of measuring tube 10 can be by the deformation of sensor basically according to the nature second eigen oscillation form, this eigen oscillation form by coplane to be superimposed upon first eigen oscillation formal.The instantaneous skew of the deformation of measuring tube 10, particularly its amplitude also depends on instantaneous mass flow m.As the second eigen oscillation form, promptly so-called coriolis mode can be the crooked oscillation form of antisymmetry with two oscillation loops or four oscillation loops for example as common in the situation of this measuring transducer.

In a development of the present invention, at least discontinuously with the swaying frequency f _ExcL Excitation measuring tube 10, in flow media, to produce the Coriolis force that depends on mass rate, this swaying frequency is as far as possible accurately corresponding to the minimum natural torsion eigenfrequency of measuring tube 10, thereby swaying but the measuring tube 10 that do not have fluid to flow through is outwardly-bent substantially symmetrically with respect to the axis of centres perpendicular to the measuring tube longitudinal axes L, and have single antinode in this case.For example, be that 20mm, wall thickness are about 1.2mm, length and are about 350mm and have in the common accrete situation at Nominal Width as the stainless-steel tube of measuring tube 10, this minimum crooked eigenfrequency can be in the about scope of 850Hz～900Hz.

In another development of the present invention, at least discontinuously, particularly with the swaying of effective model side by side with the torsional oscillation frequency f _ExcT Excitation measuring tube 10, in the medium that flows, to produce the shearing force that depends on viscosity, this torsional oscillation frequency as far as possible accurately corresponding to measuring tube 10 reverse eigenfrequency naturally, thereby it substantially according to natural torsional oscillation form around its longitudinal axes L distortion; About this point, for example referring to US-A 45 24 610, US-A 52 53533, US-A 60 06 609 or EP-A 1 158 289.For example in the situation of straight measuring tube, the minimum eigenfrequency of reversing can be greatly in two times scope of minimum crooked eigenfrequency.

Just as already noted, the vibration of measuring tube 10 is on the one hand owing to particularly being decayed by the energy dissipation on medium of sensor for viscosity measurement.Yet, on the other hand because with the parts of measuring tube 10 mechanical couplings of vibration, for example converter shell 100 or the pipeline that adheres to are energized vibration equally, so the oscillation energy of this measuring tube also can reduce.Although the energy loss of not expecting to converter shell 100 is actually and can calibrates, at least to around the measuring transducer particularly the energy loss to pipeline take place in mode not reproducible and that even can not estimate.The possible loss of oscillation energy to environment from additionally providing antihunter 20 in measuring transducer in order to suppress or to prevent, it is fixed on the entrance side and the outlet side of measuring tube 10.Schematically show as Fig. 2, antihunter 20 is a formation preferably.If desired, antihunter 20 can also be made of a plurality of parts shown in US-A 59 69 265, EP-A 317 340 or WO-A 00/14485, is perhaps realized by two separated portions antihunters of inlet that is fixed on measuring tube 10 and outlet side; Referring to Fig. 6.Antihunter 20 be used for at least one predetermined measuring transducer operating period be expected to modal or or even critical Media density value, the mobile equilibrium measuring transducer makes that the transverse force and/or the bending moment major part that may occur are compensated in the measuring tube 10 of vibration; About this point, referring to US-B 66 91583.In addition, antihunter 20 also is energized in the above-mentioned situation of torsional oscillation in operation at measuring tube, also produce detorsion moment, it compensates this torsional moment that is produced by the single measuring tube 10 that preferably twists around its longitudinal axes L to a great extent, thereby the pipeline that keeps particularly adhering to around the measuring transducer is avoided dynamic torsional moment to a great extent.Shown in Fig. 2 and 3, antihunter 20 can be tubulose, and for example is connected with measuring tube 10 like this with endpiece 12# at the inlet end 11# of measuring tube 10, makes it coaxial with measuring tube 10 basically as shown in Figure 3.For practical application, the material of antihunter 20 can be the material that measuring tube 10 can be used, that is, for example be stainless steel, titanium alloy etc.

In addition, measuring transducer 1 has around the measuring transducer shell 100 of measuring tube 10 and antihunter 20, the moisture that it is protected these elements not influenced by dangerous environment and/or may distribute to environment from measuring transducer.Show here among the embodiment that measuring transducer shell 100 is fixed to the inlet end of inlet pipeline section and the endpiece of outlet pipe section, makes measuring tube and antihunter oscillatorily to be suspended in the measuring transducer shell 100.In addition, measuring transducer shell 100 has neck shape transition piece, and the electric-device housing 200 that holds measuring tube instrument electronic device 50 is fixed on this transition piece; Referring to Fig. 1.

Particularly compare with measuring tube 10, antihunter 20 reverse and/or the elasticity of flexure less, make this antihunter vibrate during operation equally, and identical with the frequency of measuring tube 10 in fact basically but phase place is different, particularly anti-phase.When keeping such, antihunter 20 is adjusted to have at least one it reverses eigenfrequency, and this frequency as far as possible accurately equals one of torsional oscillation frequency that measuring tube 10 vibrates during operation.In addition, as far as possible accurately adjust antihunter 20 and be at least one its crooked eigenfrequency, this frequency equals at least one crooked oscillation frequency that measuring tube 10 particularly vibrates in effective model, and also encourage antihunter 20 swayings in the operating period of measuring transducer, particularly crooked vibration, this basically with the swaying of the measuring tube 10 bending vibration coplane of effective model particularly.

In a development of the present invention, as shown in Figure 3, groove 201,202 is provided in antihunter 20, is used for making it possible to accurately to adjust it and reverses eigenfrequency, particularly reduce and reverse eigenfrequency by the torsional rigidity that reduces antihunter 20 in simple mode.Although display channel 201,202 is evenly distributed on the direction of longitudinal axes L basically in Fig. 2 and 3, if desired, they certainly anisotropically are distributed on the direction of longitudinal axes L.In addition, as what schematically show in Fig. 3 equally, the mass distribution of antihunter also can utilize the corresponding mass balance body 101,102 that is fixed on the measuring tube 10 to proofread and correct.Mass balance body 101,102 can for example be to shift becket on the measuring tube 10 or little metal dish fixed thereon onto.

In order to obtain the mechanical oscillation of measuring tube 10, measuring transducer also comprises the exciting bank 40 that is coupled to measuring tube, particularly dynamic drive device.Exciting bank 40 is used for the excitation electric energy P that will present from the measurement instrument electron device _ExcBe converted to excitation moment M _ExcAnd/or exciting force F _Exc, wherein encourage electric energy P _ExcFor example has exciting current i through regulating _ExcAnd/or the voltage through regulating, excitation moment M _ExcFor example the form with pulse or harmonic wave acts on measuring tube 10 and makes its elastic deformation, exciting force F _ExcLaterally act on the measuring tube 10.In order to reach possible top efficiency and highest signal to noise ratio, excitation electric energy P is set as far as possible accurately _Exc, make to keep the vibration of measuring tube 10 in effective model on the principle, and this vibration in fact as far as possible accurately has the instantaneous eigenfrequency by the measuring tube of MEDIA FLOW warp.In this case, in fact as schematically showing exciting force F in Fig. 4 and 6 _ExcWith excitation moment M _ExcCan be respectively two-way, perhaps be unidirectional, and for example utilize electric current and/or their amplitude of voltage regulator circuit adjustment and for example utilize phaselocked loop to adjust their frequency in mode well known to those skilled in the art.As common in this vibration-type measuring transducer, exciting bank 40 can for example be the piston coil device, it has and is mounted to antihunter 20 or from the cylindrical drive coil of converter shell 100 internal fixation, this coil conducts corresponding excitation current i during operation _Exc, and this piston coil device has the permanent magnetism armature on the measuring tube 10 of being fixed on that inserts drive coil to small part.In addition, exciting bank 40 can also for example show in US-A 45 24 610 or WO-A 03/09950, utilizes a plurality of piston coils to realize or utilize high-speed double electromagnet.

In order to detect the vibration of measuring tube 11, measuring transducer 10 also comprises sensor device 60, and its first osciducer 17 that utilizes at least one that the vibration of measuring tube 10 is reacted produces the first oscillation measurement signal s of representative vibration ₁, it is simulating signal particularly.Osciducer 17 can for example utilize the permanent magnetism armature to form, this armature be fixed to measuring tube 10 and with the cell winding alternating action that is installed on antihunter 20 or the converter shell.Be specially adapted to those sensors of the deflection speed that is based on electric principle and detection measuring tube 10 of osciducer 17.Yet, the electrodynamic transducer of measurement acceleration, even the resistance or the optical sensor of measurement journey time also can use.Certainly, also can use well known to those skilled in the art and be suitable for detecting other sensor of this vibration.Sensor device 60 also comprises second osciducer 18, and it is identical with first osciducer 17 especially, utilizes it to send the second oscillation measurement signal s that represents the vibration of measuring tube 10 equally ₂In this embodiment, two osciducers 17,18 are arranged in the measuring transducer 10 along measuring tube 10 separated from one anotherly, especially, equate with the mid point of measuring tube 10 distance, thereby utilize the vibration of the inlet of sensor device 60 local detection measuring tubes 10 and outlet side and convert them to corresponding oscillation measurement signal s ₁And s ₂These two measuring-signal s ₁, s ₂Usually has signal frequency separately corresponding to the ringing frequency of measuring tube 10, as shown in Figure 2, these two measuring-signals are admitted to measurement instrument electron device 50, and they are utilized the manner known in the art pre-service there, particularly digitizing, and analyzed suitably subsequently.

In one embodiment of the invention, shown in Fig. 2 and 3, like this structure and exciting bank 40 is set in measuring transducer, make it in operation side by side, act on measuring tube 10 and the antihunter 20 particularly differentially.In of the present invention this further developed, as shown in Figure 2, preferably such structure also was provided with exciting bank 40 in measuring transducer, make it in operation side by side, acts on measuring tube 10 and the antihunter 20 particularly differentially.In the embodiment shown in fig. 4, exciting bank 40 has the first drive coil 41a, and it flows through exciting current or exciting current component during operation at least discontinuously.Drive coil 41a is fixed to the lever 41c that is connected to measuring tube 10, and 20 armature 41b acts on measuring tube 10 and the antihunter 20 differentially by this lever with from external stability to antihunter.This device also has the following advantages: on the one hand, antihunter 20 and converter shell 100 are retained as on the cross section less, and however, particularly also can easily reach drive coil 41a at assembly process.In addition, another advantage of this embodiment of exciting bank 40 is, the coil cup 41d that may use can be fixed on equally on the antihunter 20 and thereby in fact for the not influence of eigenfrequency of measuring tube 10, this coil cup no longer is insignificant in the weight of Nominal Width during greater than 80mm particularly.Yet, should be noted in the discussion above that here that if desired drive coil 41a can also be supported by antihunter 20, and the tested buret 10 of armature 41b is supported.

In the corresponding way, can also design like this and osciducer 17,18 is set in measuring transducer, make them detect the vibration of measuring tube 10 and antihunter 20 differentially.In the embodiment shown in fig. 5, sensor device 50 comprises the cell winding 51a that is fixed on the measuring tube 10, and it is positioned at the outside of all principal axis of inertia of sensor device 50 here.The contiguous as far as possible armature 51b that is fixed on the antihunter 20 of cell winding 51a, and like this and this armature 51b magnetic coupling, make in cell winding the measuring voltage that induction changes, this voltage be subjected to the influence of the relative motion that rotation between measuring tube 10 and the antihunter 20 and/or horizontal relative position and/or relative spacing change.Based on this set of cell winding 51a, the bending of above-mentioned torsional oscillation and excitation vibration is all had advantage ground and is detected simultaneously.Yet if desired, cell winding 51a also can be fixed on the antihunter 20 for this reason, and in the corresponding way, is fixed on the measuring tube 10 with the armature 51b of its coupling.

In another embodiment of the present invention, measuring tube 10, antihunter 20 and the sensor and the exciting bank 40,50 that are fixed on them are matching each other aspect their mass distribution like this, make the utilization inlet of formation like this and the measuring transducer interior section that outlet pipe section 11,12 hangs have the MS of mass centre, it is positioned at the inside of measuring tube 10 at least, however its preferably as close as possible measuring tube longitudinal axes L.In addition, interior section has such formation of advantage, makes it have first principal axis of inertia T ₁, its with the inlet pipeline section 11 and outlet pipe section 12 aligns and at least the piecewise be positioned at measuring tube 10 inside.Because the skew of the MS of mass centre of interior section is particularly also because above-mentioned first principal axis of inertia T ₁The position, take by measuring tube 10 during operation and subsequently by the oscillation forms of antihunter 20 compensation, that is, the torsional oscillation of measuring tube 10 and crooked vibration are by farthest mechanically decoupled each other for these two kinds; About this point, referring to WO-A 03/095950.By this way, two kinds of oscillation forms, that is, swaying and/or torsional oscillation can have advantage ground and encourage separated from one anotherly.Work as interior section, be that measuring tube 10, antihunter 20 and the sensor and the exciting bank 50,40 that are fixed on them are constructed like this and be provided with, make interior section symmetrical substantially along the mass distribution of measuring tube longitudinal axes L, at least with respect to centering on the virtual Rotate 180 of measuring tube longitudinal axes L ° constant (c2 symmetry), the then MS of mass centre and first principal axis of inertia T ₁Skew with respect to the measuring tube longitudinal axes L all for example can significantly be simplified.In addition, here, tubulose particularly be mainly axisymmetric antihunter 20 basically with measuring tube 10 coaxial settings, thereby significantly simplified the acquisition that the Symmetric Mass of interior section distributes, and thereby the MS of mass centre is close to the measuring tube longitudinal axes L in simple mode.In addition, construct and on measuring tube 10 and antihunter 20, be provided with sensor and exciting bank 50,40 in this embodiment like this, make the mass inertia moment that produces by them form concentrically with the measuring tube longitudinal axes L as far as possible, perhaps keep it as far as possible little at least.This can for example make the same as close as possible measuring tube longitudinal axes L of public mass centre of sensor and exciting bank 50, the 40 and/or gross mass of sensor and exciting bank 50,40 kept as far as possible little.

In of the present invention further developing, in order to encourage reversing and/or crooked vibration of measuring tube 10 discretely, construct exciting bank 40 like this and secure it to measuring tube 10 and antihunter 20, the power that make to produce crooked vibration acts on measuring tube 10 along the virtual line of force, and this line of force is perpendicular to first principal axis of inertia T ₁Second principal axis of inertia T ₂Outside extend or with second principal axis of inertia T ₂Basically intersect on one point.Preferably, construct interior section like this, make second principal axis of inertia T ₂Basically consistent with above-mentioned central axial line.In the embodiment shown in fig. 4, exciting bank 40 has at least one first drive coil 41a for this reason, it flows through exciting current or exciting current component in operation at least discontinuously, this first drive coil is fixed to the lever 41c that is connected to measuring tube 10, and 20 armature 41b acts on measuring tube 10 and antihunter 20 differentially by this lever with from external stability to antihunter.This device also has the following advantages: on the one hand, antihunter 20 and converter shell 100 are held ground on the cross section less, and however, particularly also can easily reach drive coil 41a at assembly process.In addition, another advantage of this embodiment of exciting bank 40 is, the coil cup 41d that may use can be fixed on equally on the antihunter 20 and thereby in fact for the not influence of resonance frequency of measuring tube 10, the weight of this coil cup no longer is insignificant at Nominal Width during greater than 80mm particularly.Yet, should be noted in the discussion above that here that if desired drive coil 41a can also be supported by antihunter 20, and the tested buret 10 of armature 41b is supported.

In of the present invention further developing, exciting bank 40 has at least one second drive coil 42a, and it is coupled to measuring tube 10 and antihunter 20 along the diameter setting of measuring tube 10 and in the mode identical with drive coil 41a.In another advantageous development of the present invention, exciting bank has two other drive coil 43a, 44a, that is to say always to have four at least with respect to second principal axis of inertia T ₂Be symmetrical arranged and all be installed in drive coil in the measuring transducer in the mode that illustrates previously.Utilize this two or four coil devices, can be in simple mode, for example by to one of drive coil for example drive coil 41a the induction coefficient different with other is provided, perhaps by make one of drive coil for example drive coil 41a flow through the exciting current component different in operation with the exciting current component of other drive coil, and be created in the second axis of inertia T ₂Outside act on the power of measuring tube 10.

In another development of the present invention, schematically show as Fig. 5, sensor device 50 comprises cell winding 51a, it is fixed on the measuring tube 10 and is arranged on second principal axis of inertia T ₂Outside.The as close as possible armature 51b that is fixed on the antihunter 20 of cell winding 51a, and with the such magnetic coupling of this armature 51b, make in cell winding the measuring voltage that induction changes, this measuring voltage be subjected to the influence of the relative motion that rotation between measuring tube 10 and the antihunter 20 and/or horizontal relative position and/or relative spacing change.Based on this set of cell winding 51a, the bending of above-mentioned torsional oscillation and excitation vibration is all had advantage ground and is detected simultaneously.Yet if desired, cell winding 51a also can be fixed on the antihunter 20 for this reason, and in the corresponding way, is fixed on the measuring tube 10 with the armature 51b of its coupling.

Further, be noted that here and can construct exciting bank 40 and sensor device 50 has essentially identical physical construction in mode well known to those skilled in the art; Thereby the embodiment of the physical construction of above-mentioned exciting bank 40 can be converted into the physical construction of sensor device 50 basically, and vice versa.

In order to make measuring tube 10 vibration, as already mentioned, that utilizes equally particularly multifrequency vibration has degree of amplitude modulation and an adjustable excitation frequency f _ExcExciting current i _Exc,, make drive coil 26,36 during operation be flowed through and correspondingly produce the required magnetic field of mobile armature 27,37 by such electric current by this way to exciting bank 40 power supply.Exciting current i _ExcIt can for example be harmonic wave, multifrequency or or even rectangle.Have advantage ground in the measuring transducer that can show in an embodiment and select and adjust exciting current i like this _ExcKeep measuring tube 10 swayings required transverse current component i _ExcLSwaying excitation frequency f _ExcL, make the measuring tube 10 of swaying vibrate with bending vibration basic model as much as possible, have single oscillation loop.Similar with it, have advantage ground in the measuring transducer that can show in an embodiment and select and adjust exciting current i like this _ExcKeep measuring tube 10 torsional oscillations required reverse current component i _ExcTTorsional oscillation excitation frequency f _ExcT, make the measuring tube 10 of torsional oscillation vibrate with the torsional oscillation basic model as much as possible, have single oscillation loop.

For above-mentioned situation, the swaying frequency f that measuring tube vibrates during operation and had _ExcLWith the torsional oscillation frequency f _ExcTDiffer from one another with being adjusted, even at the same time excitation reverse and the situation of crooked vibration in, also can utilize measuring transducer for example to be implemented in and separate each mode of oscillation in pumping signal and the sensor signal based on signal filtering or frequency analysis in simple and mode with advantage.

In order to produce and regulate exciting current i _Exc, measurement instrument electron device 50 comprises suitable driving circuit 53, it is by representative swaying excitation frequency f to be provided with _ExcLSwaying frequency configuration signal y _FMLAnd represent exciting current i _ExcAnd/or transverse current component i _ExcLThe swaying amplitude signalization y of swaying amplitude to be provided with _AMLControl, and driving circuit 53 is also at least discontinuously by representative torsional oscillation excitation frequency f to be provided with _ExcTTorsional oscillation frequency configuration signal y _FMTWith represent exciting current i _ExcAnd/or reverse current component i _ExcTThe torsional oscillation amplitude signalization y of torsional oscillation amplitude to be provided with _AMTControl.The baric flow converter that driving circuit 53 can for example utilize voltage controlled oscillator to be connected with the downstream is realized; Yet, replacing simulative generator, for example numerically controlled digital oscillator also can be used to adjust instantaneous exciting current i _ExcOr the component i of exciting current _ExcL, i _ExcT

In order to produce swaying amplitude signalization y _AMLAnd/or torsional oscillation amplitude signalization y _AMT, can use the amplitude regulating circuit 51 that for example is integrated in the measurement instrument electron device 50, it is based on two oscillation measurement signal s with instantaneous swaying frequency and/or instantaneous torsional oscillation frequency measurement ₁, s ₂In at least one instantaneous amplitude and based on suitable constant or variable amplitude reference value W for horizontal or torsional oscillation _B, W _T, realize amplitude signalization y _AML, y _AMTIf desired, exciting current i _ExcInstantaneous amplitude also can introduce, be used to generate swaying amplitude signalization y _AMLAnd/or torsional oscillation amplitude signalization y _AMTReferring to Fig. 7.The structure of this amplitude regulating circuit and function are known equally for those skilled in the art.As the example of this amplitude regulating circuit, measurement transmitter of " PROMASS80 " series that can also the application reference people provides is for example in conjunction with " PROMASS I " measurement series transmitter.Preferably design its amplitude regulating circuit like this, make the swaying of measuring tube 10 be adjusted to the amplitude of constant (that is, being independent of density p).

Frequency adjustment circuit 52 and driving circuit 53 can for example be embodied as phaselocked loop, and it uses in the manner known to persons skilled in the art, are used for based on oscillation measurement signal s ₁, s ₂In at least one with exciting current i that will adjust or transient measurement _ExcBetween the phase differential measured, with swaying frequency configuration signal y _FMLAnd/or torsional oscillation frequency configuration signal y _FMLAdjust to the instantaneous eigenfrequency of measuring tube 10 continuously.This structure and using that is used for driving with mechanical eigenfrequency the phaselocked loop of measuring tube for example specifies at US-A 48 01 897.Certainly, can use other frequency adjustment circuit well known by persons skilled in the art, such as the circuit in US-A 45 24610 or US-A 48 01 897.In addition, about of the application of this frequency adjustment circuit, with reference to already mentioned " PROMASS 80 " measurement series transmitter for vibration-type measuring transducer.Also can from for example US-A 58 69 770 or US-A 65 05 519, obtain being applicable to other circuit of driving circuit.

In another embodiment of the present invention, schematically show as Fig. 7, amplitude regulating circuit 51 and frequency adjustment circuit 52 be the digital signal processor DSP provide in measurement instrument electron device 50 is provided and in DSP the program code of corresponding realization and operation realize.Program code can be temporarily or even for good and all for example be stored in the nonvolatile memory EEPROM of microcomputer 55 of control and/or pilot signal processor, and can during enabling signal processor DSP, be written into measurement instrument electron device 50 for example be integrated in volatile data memory RAM among the signal processor DSP.The signal processor that is applied to this can obtain on market, for example the TMS320VC33 of Texas Instruments Inc..Certainly, verified in the practice, be used at the pretreated oscillation measurement signal of signal processor DSP s ₁, s ₂Be utilized corresponding modulus converter A/D and be converted to digital signal corresponding; About this point, referring to EP-A 866 319.If desired, the adjustment signal that is sent by signal processor is such as amplitude signalization y _AML, y _AMTOr frequency configuration signal y _FML, y _FMTCan be by digital-to-analog conversion in the corresponding way.

As shown in Figure 7, oscillation measurement signal s ₁, s ₂Also be fed to the metering circuit 21 of measurement instrument electron device.The metering circuit 21 that constitutes as flow computer to small part is used in mode well known to those skilled in the art based at two suitable preregulated oscillation measurement signal s ₁, s ₂Between the phase differential that detects and determine mass flow measurement X corresponding to mass rate to be measured _mWhat be applicable to metering circuit 21 is existing particularly digital measurement circuit, and it is based on oscillation measurement signal s ₁, s ₂Determine mass rate; About this point, referring to the WO-A02/37063 that mentions at first, WO-A 99/39164 or US-A 56 48 616 and US-A 50 69 074.Certainly, other metering circuit well known by persons skilled in the art also goes for Coriolis mass flowmeter, is used to measure and analyze suitably phase place and/or mistiming between the oscillation measurement signal of described type.To have the mode of advantage, metering circuit 21 utilizes signal processor DSP to realize equally.Metering circuit 21 also is used to produce the density measurement X of instantaneous representative Media density ρ or medium phase place _ρ

As already mentioned in the prior art part, the formation of the heterogeneity in the flow media and/or the first and second medium phases, for example bubble that mixes in the liquid and/or solid particle, the measured value that can mean supposition single phase and/or uniform dielectric and determine in common mode can not enough accurately realistic mass rate, that is, it must correspondingly be proofreaied and correct.The measured value ad representative mass rate that this is determined at first or corresponding with it at least, it can be at oscillation measurement signal s in the simplest situation ₁, s ₂Between the phase differential measured, thereby, be referred to as the first intermediate value X ' below _mFinally, analytical electron device 21 is by this first intermediate value X ' _mObtain enough accurately mass flow measurement X of representation quality flow _mAbout this point, discuss to some extent in the prior art, in the measurement instrument that uses described type, the heterogeneity in this medium directly influences two oscillation measurement signal s ₁, s ₂Between each oscillation amplitude and oscillation frequency in the phase differential measured and two oscillation measurement signals or the exciting current, and thereby in fact influence the operating parameter that each measurement instrument that utilizes described type is directly or indirectly measured usually.In fact, especially as in WO-A 03/076880 or US-B 65 05 519, explaining, especially such for the operating parameter of in the situation of the measuring tube of swaying, determining; Yet, can not get rid of the operating parameter that the measuring tube that utilizes torsional oscillation is measured; About this point, especially referring to US-A 45 24 610.

Yet inventor's further investigation has obtained wonderful discovery, that is, although instantaneous exciting current i _ExcDepend on the heterogeneity of two-phase or multiphase medium to a great extent with dielectric viscosity that the measuring tube oscillatory extinction of usually also measuring in measurement instrument operating period that accompanies and/or operating period measure and/or depend on second mutually the concentration of same media, for example from the distribution and/or the amount of the bubble that in testing liquid, mixes and/or the solid particle of ejecta, although have at least above-mentioned basic model laterally and the influence of torsional oscillation, at instantaneous exciting current i _ExcOr its active constituent i _ExcL, i _ExcTWith the heterogeneity or second of two-phase or multiphase medium represent between the concentration of (in particular as second phase of disturbing) mutually bigger reproducibility and thereby supposition can test definite relation at least.In addition, be surprised to find, consider the phase place of the practical viscosity or the testing medium of testing medium, and be considered as the long-pending exciting current i that measures of the apparent viscosity or the viscosity-density of the medium of guiding in the measuring tube 11 _Exc, perhaps keep the required exciting current component i of ringing of measuring tube based at least one _ExcL, i _ExcT, can carry out intermediate value X ' _mCorrection.

Even in order in the situation of two-phase or multiphase medium, also accurately to measure mass rate, utilize measurement instrument electron device 2 during operation based on exciting current i particularly through regulating _ExcAnd/or its i _ExcL, i _ExcTComponent forms the particularly second intermediate value X of numeral ₂The second intermediate value X ₂Oscillatory extinction corresponding to measuring tube 11.It is long-pending that this decay depends in the measuring tube 11 apparent viscosity and/or the viscosity-density of medium of guiding.In addition, metering circuit 21 is by using the second intermediate value X ₂And the initial viscosity measurement value X that determines suitably of consideration _η, determine for intermediate value X ' _mCorrected value X _K, it is digital value especially equally, wherein viscosity measurement value is corresponding to the practical viscosity of the medium of guiding in measuring tube 11 or at least corresponding to for medium reference viscosity given in advance.Based on corrected value X _KAnd to intermediate value X ' _mCorrection of carrying out and mass flow measurement X _mGeneration can in the measurement instrument electron device, for example carry out according to following mathematical relation:

X _m＝K _m·(1+X _K)·X _m′ (1)

In an embodiment of the present invention, corrected value X _KUtilize the measurement instrument electron device to determine based on following mathematical relation:

X _K＝K _K·(X ₂-X _η) (2)

Thereby in fact this is the apparent viscosity η of the medium that guides in dielectric viscosity η and the measuring tube ^*And/or with measuring tube in the measuring of deviation delta η of long-pending η ρ of viscosity-density of the medium that guides, wherein apparent viscosity is during operation based on exciting current i _ExcAnd/or exciting current i _ExcComponent determine, viscosity-density long-pending be during operation based on exciting current i _ExcDetermine.As an alternative or replenish, can further determine corrected value X based on following mathematical relation _K:

$X_K={K_K}^{\′}\·(1-\frac{X_{\mathrm{\η}}}{X_2})---\left(3\right)$

So, although in equation (2), corrected value X _KBe based on intermediate value X ₂With viscosity measurement value X _ηBetween the poor Δ η that exists and definite, wherein viscosity measurement value is in fact corresponding to the absolute error between two measured values; And equation (3) is based on the second intermediate value X ₂With viscosity measurement value X _ηComparison or based on two measured value X ₂, X _ηBetween relative error Δ η/η ^*And definite corrected value X _KIn this respect, at least for two-phase medium, corrected value X _KAlso represent medium first or second phase instantaneous relatively or the measuring of absolute concentration, wherein said first or second bubble in the liquid specifically mutually.Except generating mass flow measurement X _m, intermediate value X ₂Can also have that advantage ground for example is used at the scene in addition or in remote control room in visual mode with the heterogeneity degree of signal indication medium or the measurement result that obtains thus, such as volume, quality or the quantity number percent of air content in the medium or the solid particle that in medium, mixes.

Experiment in addition shows, for the measuring transducer according to illustrated embodiment, considers that the instantaneous swaying frequency of the measuring tube of vibration can cause further improving mass flow measurement X _mPrecision.In addition, corrected value X that utilizes the square root of instantaneous swaying frequency to determine from equation (2) or (3) _KNormalization can be so that corrected value X _KBasically proportional with gas ratio, at least for liquid to be measured for example glycerine mix have bubble for example the situation of air be such; About this point, referring to Fig. 9.So, further develop according to of the present invention, use the swaying frequency measurement X of the instantaneous swaying frequency of representative _FexcLRevise equation (2):

$X_K=K_K\·\frac{(X_2-X_{\mathrm{\η}})}{\sqrt{X_{\mathrm{fexcL}}}}---\left(4\right)$

Determining of swaying frequency measurement can be in simple mode for example based on above-mentioned swaying frequency adjusted signal y _FMLFinish.

The decay of the vibration of known measuring tube 10 is not only by for the contributive attenuation components of the viscous friction in the medium but also definite by the attenuation components that in fact is independent of medium.The latter is caused by for example mechanical friction power in the material internal effect of exciting bank 40 and measuring tube 10.In other words, the exciting current i of transient measurement _ExcRepresent total frictional force and/or moment of friction in the measuring transducer 10, it comprises mechanical friction in the measuring transducer and the viscous friction in the medium.As already mentioned, intermediate value X ₂Should be mainly corresponding to the contributive decay of the viscous friction in the medium, when determining this intermediate value, the mechanical attenuation components that is independent of medium will be considered suitably, particularly separates suitably or elimination.

In order to determine intermediate value X ₂, in one embodiment of the invention, from instantaneous representative exciting current i _ExcParticularly the numeral total exciting current measured value X _IexcIn, and/or from instantaneous representative transverse current component i _ExcLParticularly the numeral transverse current measured value X _IexcLIn, and/or reverse current component i from instantaneous representative _ExcTParticularly numeral reverse current measurement value X _IexcTIn, correspondingly respectively deduct total no-load current measured value K _Iexc, horizontal no-load current measured value K _IexcL, reverse no-load current measured value K _IexcT, they represent the mechanical friction power that produces separately in measuring transducer in the situation of no-load measuring tube 10.Each no-load current measured value K _Iexc, K _IexcL, K _IexcTEqually for example be used for being determined during the Coriolis mass flowmeter of measuring tube 10 emptying or that only contain air, determine and particularly turned to relative measurement oscillation amplitude accordingly by specification to preserve or to be adjusted at measurement instrument electron device 50 in calibration.Need not further explanation, those skilled in the art are very clear, if desired, can consider to influence no-load current measured value K during calibration _Iexc, K _IexcL, K _IexcTOther physical parameter, the transient temperature of measuring tube and/or medium for example.For calibration measurement transmitter 10, usually order have change but two or more two-phase or multiphase different medium continuous stream of known flow parameter through measuring transducer 10, and the corresponding retroaction of measured value transmitter 10 is measured, wherein flow parameter for example is concentration known, density p, mass rate m, viscosities il and/or the temperature of each medium phase of calibrate medium, and retroaction for example is instantaneous exciting current i _Exc, instantaneous swaying excitation frequency f _ExcLAnd/or instantaneous torsional oscillation excitation frequency f _ExcTEach of the flow parameter of the setting of measuring transducer 10 and the operating parameter of measurement measured retroaction and matched each other suitably, and thereby reflected corresponding calibration constants.For example, in order in situation, to determine constant for the calibration measurement of two kinds of calibrate mediums of known-viscosity, the viscosity that keeps constantly as far as possible and with difference but the heterogeneity that constant mode forms forms definite intermediate value X _m' or definite mass flow measurement X _mRatio X with current mass rate when the known air ratio _m'/m and/or X _m/ m.For example, first calibrate medium can be to mix alveolate circulating water or oil, and second calibrate medium can be uniform as far as possible water or oil.So, the calibration constants of determining can be for example with digital store in the table storer of measurement instrument electron device; Yet they also can be as the simulation value of setting for corresponding counting circuit.The calibration that is noted here that the measuring transducer of described type is well known by persons skilled in the art, perhaps can need not further to explain based on above-mentioned explanation understanding at least.Has advantage, in order to determine total exciting current measured value X _Iexc, transverse current measured value X _IexcLAnd/or reverse current measurement value X _IexcT, can use already mentioned swaying amplitude signalization y _AMLAnd/or torsional oscillation amplitude signalization y _AMT, because they have enough accurately represented exciting current i for proofreading and correct _ExcOr its component i _ExcL, i _ExcT

In another embodiment of the present invention, as shown in Figure 8, corrected value X _KDetermine it is the current measurement value X that for example determines by service test _IexcL, X _IexcTWith no-load current measured value K _IexcL, K _IexcTBased on the transverse current component i that drives swaying _ExcLAnd based on relevant horizontal no-load current measured value K _IexcL, particularly carry out based on following mathematical relation:

X ₂＝K ₂·(X _iexcL-K _iexcL) (5)

And/or based on following mathematical relation:

${\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="A20058000852700441.png,A20058000852700451.png"\; state="\{\{state\}\}">X</figure-callout>}}_2={{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="A20058000852700441.png,A20058000852700451.png"\; state="\{\{state\}\}">K</figure-callout>}}_2}^{\&prime;}\&CenterDot;(1-\frac{K_{\mathrm{iexcL}}}{X_{\mathrm{iexcL}}})---\left(6\right)$

When needed, particularly significantly change during operation and/or depart from the situation of reference value of calibration, can for example use oscillation measurement signal s equally in advance in the oscillation amplitude of measuring tube of vibration ₁, s ₂With transverse current component i _ExcLRinging amplitude for the swaying of measuring tube is standardized.

In another embodiment of the present invention, viscosity measurement value X _ηRepresent predetermined with reference to viscosity.For example, this can be based on the understanding of testing medium and from the Long-distance Control position or manually send into or be sent to via fieldbus from outside viscosity meter the viscosity measurement value of measurement instrument electronic installation at the scene.

In of the present invention further developing, viscosity measurement value X _ηUtilizing it to measure electron device 2 produces.

For above-mentioned situation, promptly, make straight measuring tube in operation simultaneously or alternately laterally reach the situation of torsional oscillation, also can use the directly definite viscosity measurement value of measuring transducer 1 and measurement instrument electron device 2 by Coriolis mass flowmeter 1 in operation.Just as is known, straight measuring tube is being energized around substantially with the parallel or consistent torsional oscillation axis torsional oscillation of measuring tube longitudinal axis the time, make in guiding runs through wherein medium, to produce shearing force, thereby from torsional oscillation, eliminated significant oscillation energy.As a result, since the remarkable decay of the torsional oscillation of the measuring tube of vibration, the excitation electric energy P that must will add _ExcBe fed to measuring tube to keep its vibration.The required excitation electric energy P of torsional oscillation of measuring tube 10 is kept in use _ExcT, those skilled in the art can use measuring transducer at least generally to determine the viscosities il of medium in known manner; About this point, especially referring to US-A 45 24 610, US-A 52 53 533, US-A 60 06 609 or US-B 66 51 513.

Be surprised to find, although keep the required exciting current i of measuring tube 10 swayings _ExcOr transverse current component i _ExcLAnd kept the required exciting current i of measuring tube 10 torsional oscillations as what in US-A 45 24 610 or EP-A 1 291 639, discuss _ExcOr reverse current component i _ExcTDepend on the concentration of non-uniformity or each medium phase to a great extent, but the viscosity measurement value X that utilizes Coriolis mass flowmeter 1 to obtain in the above described manner _ηConclusion itself make it possible to very robust and have good reproducibility ground proofread and correct intermediate value X ' _m, and thereby can generate point-device mass flow measurement X _m

So, in first modification that further develops of the present invention, viscosity measurement value X _ηAlso measured instrument electronic device 2 generates, and this is based on the exciting current i that measuring tube drives exciting bank 40 to the situation of small part torsional oscillation _ExcDetermine, especially, reverse current component i based on what be used to keep measuring tube 10 torsional oscillations _ExcTIn addition, the viscosity measurement value X that also determines based on this inside _ηCalculate intermediate value X ₂And/or corrected value X _KConsider the following relation of explanation in US-A 4,524 610:

$\sqrt{\mathrm{\&eta;}}{~i}_{\mathrm{excT}}---\left(7\right)$

According to it, reduced the above-mentioned no-load current measured value K that reverses _IexcTReverse current component i _ExcTAt least in the situation of constant density ρ, be associated with the square root of practical viscosity η well, correspondingly, for definite viscosity measurement value X _η, at first, in measurement instrument electron device inside, from by exciting current i _ExcDeduct and reverse no-load current measured value K _IexcTWhat obtain reverses current measurement value X _IexcT, form square value X _{Δ iexcT} ²Begin thus, according to another embodiment of the present invention, determine viscosity measurement value X based on following mathematical relation numerical value _η:

$X_{\mathrm{\&eta;}}=K_{\mathrm{\&eta;}}\&CenterDot;\frac{{X_{\mathrm{\&Delta;iexcT}}}^2}{X_{\mathrm{\&rho;}}}---\left(8\right)$

K wherein _ηBe meter constant, also depend on the geometry of measuring tube 10 especially.The density measurement X that in the formula denominator, occurs _ρThe long-pending information that in fact relevant density and viscosity square are provided of only having represented electric current; About this point, referring to US-A 45 24 610.

The viscosity measurement value X definite according to this mathematical relation _ηGood approximation for the dynamic viscosity of fluid is provided, and known this dynamic viscosity can be used as the dynamic viscosity of fluid and density p is long-pending.If viscosity measurement value X _ηTo be used as the approximate of dynamic viscosity, so, before output, must be with respect to density measurement X _ρStandardize accordingly, for example utilize simple numerical value division.For this reason, equation (8) can be modified to:

$X_{\mathrm{\&eta;}}=K_{\mathrm{\&eta;}}\&CenterDot;{\left(\frac{X_{\mathrm{\&Delta;iexcT}}}{X_{\mathrm{\&rho;}}}\right)}^2---\left(9\right)$

In another embodiment of the present invention, reverse current measurement value X _IexcTSquare X _IexcT ²Quilt is with respect to amplitude measurements X _XTNormalization forms viscosity measurement value X to utilize simple numerical value division _η, the instantaneous representative of wherein said amplitude measurements is oscillation measurement signal s in the situation of the measuring tube of torsional oscillation ₁, s ₂In at least one the signal amplitude of the variation that depends on operation.So, find that also for this viscosity measurement instrument of using this vibration-type measuring transducer, and particularly this viscosity measurement instrument has the oscillation amplitude of constant adjusting and/or excitation simultaneously laterally reaches torsional oscillation, exciting current i _ExcRatio i with the movement velocity θ that in fact can not directly record that in medium, causes internal friction and friction force _Exc/ θ is being similar to more accurately for the decay of above-mentioned antagonism measuring tube 10 deformation of mentioning.So, in order further to increase viscosity measurement value X _ηPrecision, particularly also in order to reduce its susceptibility, further propose, in order to determine viscosity measurement value X for the oscillation amplitude of the fluctuation of the measuring tube 10 of contingent vibration during operation _η, at first will reverse current measurement value X _IexcTWith respect to amplitude measurements X _XTStandardize, the latter represents above-mentioned speed θ with enough precision.In other words, use following formula to form normalized current measurement value X ' that reverses _IexcT:

$X_{\mathrm{iexcT}}^{\&prime;}=\frac{X_{\mathrm{iexcT}}}{X_{\mathrm{sT}}}---\left(10\right)$

Amplitude measurements X _S1Preferably utilize measurement instrument electron device 50 for example to utilize inner amplitude measurement circuit, consistent based on the motion of recognizing the motion measuring tubes 10 that detect with sensor 51 to a great extent or the sensor 51 local vibrations that detect that in medium, cause viscous friction, and may digitized sensor signal s by at least one ₁Obtain.Use normalized current measurement value X ' that reverses _IexcT, can for example determine the viscosity measurement value according to following formula:

$X_{\mathrm{\&eta;}}=K_{\mathrm{\&eta;}}\&CenterDot;\frac{{X_{\mathrm{iexcT}}^{\&prime;}}^2}{K_f\&CenterDot;X_{\mathrm{\&rho;}}}---\left(11\right)$

The correction factor K that in this equation, introduces _fOnly be used to utilize the actual oscillation frequency weighting density measurement X of the measuring tube 10 of vibration _ρHere again noted that sensor signal s ₁Preferably proportional with the speed of particularly lateral deflection campaign of the measuring tube 10 of vibration; Sensor signal s ₁Although it is also can be for example proportional, also proportional with the distance of measuring tube 10 processes of vibrating with the acceleration of the measuring tube 10 that acts on vibration.For in the above described manner with sensor signal s ₁Be designed to and the proportional situation of speed, correction factor K _fCorresponding to the oscillation frequency of measuring tube 10 of vibration, it for example with the proportional sensor signal s of distance ₁Situation in equal the cube of oscillation frequency.

Replace measuring excitation energy E _Exc, perhaps even as it replenish, determining of dielectric viscosity can also be along measuring and analyzing suitably pressure reduction on the suitable measuring distance of pipeline or measuring tube 10; About this point, referring to US-A 53 59 881 or US-B 65 13 393.At least in measuring the cross section, be in the situation of laminar flow substantially, be used to proofread and correct intermediate value X ' _mThe viscosity measurement value can use following mathematical relation enough accurately to determine:

$X_{\mathrm{\&eta;}}=K_p\&CenterDot;\frac{X_{\mathrm{\&Delta;p}}}{X_m^{\&prime;}}\&CenterDot;X_{\mathrm{\&rho;}}---\left(12\right)$

Equation (12) is basically based on known Hagen-Poiseuille law, and wherein calibration factor K ρ is can predetermined parameter, and it depends on diameter and the length of measuring the cross section especially.In order to realize this mathematical relation, in second modification that further develops of the present invention, measurement instrument electron device 2 is coupled with differential pressure pick-up at least discontinuously, wherein at this second modification medium viscosity measured value X _ηAlso utilize measurement instrument electron device 2 to obtain, differential pressure pick-up sends the differential pressure measurement value X of the pressure reduction that representative measures along pipeline and/or along measuring tube at least discontinuously _{Δ p}

The function that provides above is used to obtain the mass flow measurement X by equation (1)～(12) expression _m, they can partly utilize signal processor DSP at least or utilize above-mentioned microcomputer 55 to realize.Respective algorithms or emulation amplitude corresponding with previous equations is provided with the function of circuit 51 or frequency adjustment circuit 52 and they is translated as executable program code in the sort signal processor, the establishment of these algorithms and implement be for those skilled in the art be familiar with and thereby need not to do specific explanations when of the present invention knowing at least more.Certainly, previous equations also can easily utilize the simulation and/or the digital computing circuit of corresponding discrete structure to represent wholly or in part in measurement instrument electron device 50.

In of the present invention further developing, in order to determine instantaneous suitable corrected value X _K, during operation basically like this from intermediate value X ₂Determine that directly promptly, mapping particularly is programmed in current intermediate value X in the measurement instrument electron device ₂With with the corrected value X of its coupling _KBetween unique relationships.For this reason, measurement instrument electron device 2 also has the table storer, has wherein stored data set in advance, and it for example is the digital correction values X that determines during the calibration Coriolis mass flowmeter _{K, i}These corrected values X _{K, i}By metering circuit via utilizing the instantaneous effective second intermediate value X ₂The storage address that obtains and directly visit.Corrected value X _KCan be for example definite like this: with instantaneous definite intermediate value X in simple mode ₂Intermediate value X with input table storer ₂The respective default value relatively, read corrected value X thus _{K, i}And being used for further calculating by analytical electron device 2, this corrected value is corresponding to the most close intermediate value X ₂Default value.Programmable read only memory, for example FPGA (field programmable gate array), EPROM or EEPROM can use the tabulation storer.The use of this table storer has the following advantages: for working time, and corrected value X _KCalculating intermediate value X ₂Can be obtained rapidly afterwards using.In addition, the corrected value X of input table storer _{K, i}Can very accurately be determined in advance, for example based on equation (2), (3) and/or (4) and utilize the least square method.

Find out as knowing, can use the correction factor that can determine very simply still less to carry out intermediate value X ' based on above explanation _mCorrection.On the other hand, can use predetermined viscosity measurement value X _ηWith predetermined intermediate value X ' _mCarry out to proofread and correct, compare with much complicated computing method of mentioning at first, such computation burden is less.Another advantage of the present invention is, at least some above-mentioned correction factors can obtain from the flow parameter that utilizes Coriolis mass flowmeter to determine without difficulty, the density that these parameters are particularly measured and/or the mass rate of measurement and/or operating parameter, the particularly oscillation amplitude of Ce Lianging, oscillation frequency and/or its exciting current in the Coriolis mass flowmeter operation, directly measured usually.

Claims (19)

1. Coriolis mass flowmeter, Coriolis mass flow/density measuring instrument or Coriolis mass and flow/viscosity measurement instrument particularly, be used for the particularly mass rate of two-phase or multiphase medium of the mobile medium of measuring channel, this Coriolis mass flowmeter involving vibrations type measuring transducer (1) and with the measurement instrument electron device (2) of this measuring transducer electric coupling

-wherein measuring transducer (1) has:

--at least one measuring tube (10), it inserts pipeline, particularly basic for straight and be used to guide testing medium, this measuring tube to communicate with the pipeline that is connected,

--exciting bank (40), act on this measuring tube (10), be used to make at least one measuring tube (10) vibration, it makes measuring tube (11) swaying at least discontinuously and/or at least in part during operation, particularly crooked vibration, and

--sensor device (50), be used to detect the vibration of at least one measuring tube (10), it sends at least one first oscillation measurement signal (s that represents the vibration of measuring tube (11) entrance side ₁) and at least one second oscillation measurement signal (s that represents measuring tube (11) outlet side to vibrate ₂), and

-measurement instrument electron device (2) wherein

--send the exciting current (i that drives exciting bank (13) at least discontinuously _Exc), and send the mass flow measurement (X that represents mass rate to be measured at least discontinuously _m),

--generate first intermediate value (X ' _m) and the second intermediate value (X ₂), wherein first intermediate value is from oscillation measurement signal (s ₁, s ₂) obtain and corresponding to mass rate to be measured and/or at two vibration survey signal (s ₁, s ₂) between phase differential, second intermediate value is from exciting current (i _Exc) and/or exciting current (i _Exc) one-component obtain and corresponding to the decay of the vibration of measuring tube (11), it is long-pending that this decay depends on the apparent viscosity and/or the viscosity-density of the medium of guiding in the measuring tube (11) especially, and

--use the second intermediate value (X ₂) and viscosity measurement value (X _η), obtain for first intermediate value (X ' _m) corrected value (X _K) and based on first intermediate value (X ' _m) and corrected value (X _K) obtain mass flow measurement (X _m), wherein viscosity measurement value is particularly to use that measuring transducer (1) and/or measurement instrument electron device (2) are determined in advance or during operation and corresponding to the viscosity of the medium that guides in measuring tube (11) and/or corresponding to the reference viscosity that before provided.

2. Coriolis mass flowmeter according to claim 1, wherein, corrected value (X _K) represent the deviation between the apparent viscosity of the medium of guiding in the viscosity of medium and the measuring tube (11) and/or viscosity-density long-pending, wherein apparent viscosity is during operation based on exciting current (i _Exc) and/or exciting current (i _Exc) one-component determine, viscosity-density long-pending be during operation based on exciting current (i _Exc) determine.

3. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) is based on the second intermediate value (X ₂) and viscosity measurement value (X _η) comparison and/or based at the second intermediate value (X ₂) and viscosity measurement value (X _η) between exist poor, determine corrected value (X _K).

4. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) also uses oscillation measurement signal (s ₁, s ₂) at least one obtain the second intermediate value (X ₂).

5. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim,

-wherein the exciting bank (13) of measuring tube (11) makes measuring tube (11) carry out torsional oscillation during operation at least discontinuously and/or at least in part, that particularly replace with swaying or with its torsional oscillation that superposes in time, this torsional oscillation centers on the measuring tube longitudinal axis that aligns substantially with measuring tube (11), the principal axis of inertia of measuring tube (11) particularly, and

-wherein measurement instrument electron device (2) is also based on the exciting current (i that drives exciting bank (13) _Exc) and/or based on exciting current (i _Exc) one-component, determine viscosity measurement value (X _η).

6. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, carry out torsional oscillation by the measuring tube (11) that exciting bank (40) drives, measuring tube torsional oscillation frequency is different with the crooked oscillation frequency of measuring tube, carries out crooked vibration by the measuring tube (11) that exciting bank (40) drives with this bending oscillation frequency.

7. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) also obtains viscosity measurement value (X _η).

8. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim,

-wherein, measurement instrument electron device (2) sends density measurement (X _ρ), this density measurement is from the first and/or second oscillation measurement signal (s ₁, s ₂) obtain and represent density of medium, and

-wherein, measure electron device (2) also based on density measurement (X _ρ) determine corrected value (X _K), particularly viscosity measurement value (X _η).

9. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) is coupled to outside viscosity measurement instrument, particularly away from the viscosity measurement instrument of Coriolis mass flowmeter setting, this viscosity measurement instrument sends viscosity measurement value (X at least discontinuously _η).

10. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) is coupled with differential pressure pick-up at least discontinuously, and this differential pressure pick-up sends the differential pressure measurement value (X of representative along the pressure differential of duct survey at least discontinuously _{Δ p}).

11. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim, wherein, measurement instrument electron device (2) is based on exciting current (i _Exc) and/or based on exciting current (i _Exc) one-component and utilize viscosity measurement value (X _η) definite at least discontinuously concentration measurement (X _C), the particularly relative volume and/or the quality ratio of a medium phase in the situation of two-phase or multiphase medium of this concentration measurement representative in measuring tube.

12. according to the described Coriolis mass flowmeter of aforementioned arbitrary claim,

-wherein, measuring tube (11) communicates by inlet pipeline section (11) that feeds inlet end (11#) and the outlet pipe section (12) that feeds endpiece (12#) with the pipeline that is connected, and

-wherein, measuring transducer be included in the inlet end (11#) of measuring tube (11) and endpiece (12#) fixing particularly with the antihunter (20) of exciting bank mechanical couplings, it particularly vibrates with measuring tube (10) during operation at least discontinuously anti-phasely.

13. be used for the use of the mass rate of measuring channel mobile two-phase or multiphase medium, particularly liquid-gas mixture according to the described Coriolis mass flowmeter of aforementioned arbitrary claim.

14. utilize the method for the mass rate of particularly two-phase or multiphase medium that flows in the Coriolis mass flowmeter measuring channel, this Coriolis mass flowmeter have vibration-type measuring transducer (1) and with the measurement instrument electron device (2) of this measuring transducer (1) electric coupling, this method may further comprise the steps:

-make testing medium flow through at least one and the measuring tube (11) that inserts pipeline of measuring transducer (1), and with exciting current (i _Exc) be fed into the exciting bank (40) with measuring tube (11) mechanical couplings of boot media, to make measuring tube (11) mechanical oscillation, particularly crooked vibration,

-make measuring tube (13) vibrate with the mode of oscillation that produces Coriolis force in the medium that is suitable for flowing through therein,

-detect the vibration of measuring tube (13) and obtain representing the first oscillation measurement signal (s of entrance side vibration ₁) and represent the second oscillation measurement signal (s of outlet side vibration ₂),

Two oscillation measurement signal (s of-use ₁, s ₂) obtain first intermediate value (X ' _m), it is corresponding to mass rate to be measured and/or two oscillation measurement signal (s ₁, s ₂) between phase differential,

-determine the second intermediate value (X ₂), it is by exciting current (i _Exc) obtain and corresponding to the decay of the vibration of measuring tube (11), it is long-pending that this decay depends on the apparent viscosity and/or the viscosity-density of the medium of guiding in the measuring tube (11) especially,

-utilize the second intermediate value (X ₂) and definite before viscosity measurement value (X _η), generate first intermediate value (X ' _m) corrected value (X _K), described viscosity measurement value is particularly used that measuring transducer (1) and/or measurement instrument electron device (2) are determined and corresponding to the viscosity of the medium of guiding in the measuring tube (11), and

-utilize corrected value (X _K) correction first intermediate value (X ' _m), and obtain representing the mass flow measurement (X of mass rate to be measured _m).

15. method according to claim 14 is further comprising the steps of:

-make the crooked vibration of measuring tube (11), in the medium of flowing through wherein, to produce Coriolis force.

16. method according to claim 15 is further comprising the steps of:

-make measuring tube (11) torsional oscillation, particularly be superimposed upon the torsional oscillation on the crooked vibration; And

-consideration exciting current (i _Exc) and/or exciting current (i _Exc) at least one make the component of measuring tube (11) torsional oscillation, determine the second intermediate value (X ₂).

17. according to each described method among the claim 14-16, wherein generate intermediate value (X ' _m) corrected value (X _K) step further comprise step:

-with the second intermediate value (X ₂) and viscosity measurement value (X _η) relatively, and/or determine the second intermediate value (X ₂) and viscosity measurement value (X _η) between poor; And

-determine the viscosity of medium with during operation based on exciting current (i _Exc) deviation of the apparent viscosity of the medium of guiding in the measuring tube (11) determined, and/or the viscosity of definite medium with during operation based on exciting current (i _Exc) the long-pending deviation of the viscosity-density of the medium of guiding in the measuring tube (11) determined.

18., further comprise step according to each described method among the claim 14-17:

-based on oscillation measurement signal (s ₁, s ₂) obtain representing the second measured value (X of Media density _ρ); And

-use second measured value (the X _ρ) obtain corrected value (X _K).

19. be used to the use of the vibration-type measuring transducer calibrating Coriolis mass flowmeter and/or have at least one measuring tube according to each described method among the claim 14-18.

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