CN102147383A - Multi-section impedance long-waist internal cone sensor and multi-phase flow measurer - Google Patents

Abstract

The invention belongs to the technical field of fluid measurement, and relates to a multi-section impedance long-waist internal cone sensor which comprises a cone throttling piece, a systolic pressure drop differential pressure transmitter, a permanent pressure loss differential transmitter and an electrical sensitive sensor, wherein the cone throttling piece is a long-waist internal cone throttling device which comprises a front-section cone body, a middle-section columnar body used as the waist part of the cone body and a rear-section cone body which are coaxially fixed at the center of a pipe through a support; an annular circulating space is formed by the three parts of the cone throttling piece and the wall of the pipe; and the electrical sensitive sensor comprises four groups of electrodes distributed on different sections in the annular circulating space, wherein two groups of similar electrodes are used for measuring the electrical conductivity of a mixed fluid, and the other two groups of similar electrodes are used for measuring the dielectric constant. The invention also provides a multi-phase flow measurer which adopts the multi-section impedance long-waist internal cone sensor and is used for measuring the multi-phase flow procedure parameters of a continuous phase within the range from a conductive phase to a non-conductive phase. The multi-section impedance long-waist internal cone sensor and the multi-phase flow measurer have the characteristics of high measuring precision, high reliability, capability of obtaining the measuring information and the like.

Description

Multi-section impedance type long waist inner cone sensor and multiphase flow measurement device

Technical field

The invention belongs to the fluid measurement technical field, be specifically related to a kind of measurement mechanism that merges differential pressure measurement principle and electrical measurement principle, be used for determining that each phase component of polyphasic flow in external phase is from conductive phase to non-conductive phase scope contains parameters such as rate, flow velocity and flow.The present invention is measured as description object with oil/gas/water multiphase, but is not limited in this application, and measurement mechanism of the present invention still is suitable in other industrial processs and chemical reaction.

Technical background

Polyphasic flow is often referred to and has flowing of two or more material simultaneously, comprises biphase gas and liquid flow, Dual-Phrase Distribution of Gas olid, liquid fixed double phase flow, liquid-liquid diphasic flow and gas-liquid liquid and gas-liquid-solid multiphase flow etc.Polyphasic flow often appears in modern project field such as power, nuclear energy, chemical industry, oil, refrigeration, metallurgy, pipeline transportation, aerospace, medicine, food and the equipment, as not realizing just can't guaranteeing the accurate measurement of its flow process parameter the reliable design and the safe operation of relevant devices in the pipeline.The popularity that polyphasic flow exists in nature and industrial process and the importance of application make it occupy crucial status in national economy and daily life.Along with power industry and petrochemical industry develop rapidly, and, impel the work of polyphasic flow area research to develop rapidly, become at present and give the front subject greatly paid close attention to both at home and abroad the pay attention to day by day of environmental protection.

Because each alternate interfacial effect and relative velocity of existing of polyphasic flow, phase interface all is random variation on time and space, and the flow characteristics that causes polyphasic flow is more than the single-phase flow complexity, and characteristic parameter is also many than single-phase flow.The oil gas water three phase flow measuring method can be divided into two aspects at present: 1, polyphasic flow is regarded as the measurement that biphase gas and liquid flow carries out flow.2, each phase component in the polyphasic flow is contained the measurement of rate.The method of wherein polyphasic flow being regarded as gas-liquid two-phase flow measurement flow mainly contains: correlation method, volumetric method, flow limit method, turbine type detection method, laser Doppler method, PIV particle imaging velocimetry, hot line hot film anemometer, process tomographic imaging technology, nuclear magnetic resonance method and Coriolis method etc., this several method has wide range of applications, but needs other subsidiary means (as densitometer etc.) to measure void fraction.The measuring method of phase content has two kinds, and the one, indirect method promptly returns by experiment or theoretical derivation draws the phase content calculating formula that physical parameter and technological parameter with the gas-liquid two-phase medium are function; The 2nd, the measurement mechanism direct method of measurement is as Electromagnetic Wave Detection method, conductance method, capacitance method, calorifics method, microwave method, γ component table method and nuclear magnetic resonance method etc.In actual measurement, generally adopt the measurement mechanism direct method of measurement to determine phase content.

Using that traditional single-phase flow measurement instrument combines with two-phase flow auxiliary parameter measurement means is a kind of main thought that solves polyphasic flow procedure parameter problems of measurement in the pipeline.Differential pressure flowmeter as orifice plate, Venturi tube, nozzle and inner cone flow meter etc., is to use maximum online flow measurement instruments of a kind of industry at present, and is also commonplace in the research of polyphasic flow procedure parameter fields of measurement.Wherein inner cone flow meter notion that the fluid throttling is retracted to pipeline center's near axis fundamentally change into utilize the coaxial cone that is installed in pipeline center with fluid gradually throttling be retracted to inner-walls of duct, determine fluid flow by differential pressure before and after measuring cone.Interior cone flow meter can be under shorter straight length condition, with wideer range ratio clean or dirty fluid is realized more accurate, more effective flow measurement, but also there are some shortcomings in himself design feature: there is pulsation in the pressure signal to exist the whirlpool district to cause herein at the cone afterbody, measuring accuracy and repeatability are reduced, and whole crushing is bigger, as flow performance inner cone flow meter is done malformation according to polyphasic flow, as inner venturi tube, spindle flowmeter and Shuttle Type Flow Meter etc., can effectively improve its precision and stability in multiphase flow measurement.Based on the multiphase flow measurement method of the responsive principle of electricity existing theory and application foundation preferably, electrical parameter (electrical impedance, specific inductive capacity etc.) by the measuring channel inner fluid changes the measurement that each phase component of realization polyphasic flow contains rate, and this method is divided into mode such as condenser type, conductance type according to the difference of measurement parameter.If adopt multi-modal sensor and multi-operation mode (excitation measurement strategies) combined method, utilize the measurement advantage of each mode, can realize the comprehensive extraction of polyphasic flow procedure parameter by Combinatorial Optimization, and the acquisition all-sidedly and accurately of flowing information.

Patent CN99257650.4, CN200420093532.6, CN200420061026.9 have announced a kind of special-shaped Venturi tube, spindle flowmeter, Shuttle Type Flow Meter that is used for restriction device respectively, be overcome in the cone flow meter some shortcomings design.The interior relatively cone flow meter of special-shaped Venturi tube is at waist, increase the equal diameter section, form annular free air space, help to improve the stability of efflux coefficient, but it is short and angle is big that kinetic energy is converted into the conical diffuser of outlet of potential energy, fluid produces whirlpool by separating after the cone, and the interior relatively cone flow meter of permanent crushing there is no obvious improvement.Spindle flowmeter and Shuttle Type Flow Meter are very approaching, only difference to some extent on appearance profile: the throttling element of spindle flowmeter is fairshaped spindle, and the fusiformis body that the throttling element of Shuttle Type Flow Meter is made up of precentrum, middle equal diameter segment body and posterior pyramids, throttling element is installed along conduit axis, the centre has one section sufficiently long equal diameter section, and forms uniform circular passage between the inner-walls of duct.These two kinds of deformable bodys are in efflux coefficient stability, anti-interference fluidity and low pressure loss all are better than interior cone flow meter, but throttling element long (4 times to internal diameter of the pipeline), the comparison heaviness seems when caliber is big, and it is single relatively to measure the polyphasic flow procedure parameter, needs to cooperate the measurement of other flowmeters ability complete process parameters.

Patent CN86207384, CN200810151346.6, CN03234526.7 have announced " mixer+double-venturi tube " moisture measuring device that Venturi tube restriction device and throttle orifice plate apparatus combination, inner cone restriction device and the combination of Venturi tube restriction device, the combination of two inner cone restriction device and Britain Solartron company propose respectively, adopt two differential pressure methods to measure gas-liquid two-phase and contain rate and flow, be i.e. two kinds of similar or inhomogeneous restriction device multiple measurement biphase gas and liquid flow procedure parameters.Utilize the homogeneous flow model, the differential pressure signal that obtains on the restriction device to the different flow coefficient is handled, obtain the gas phase quality and contain rate, obtain gas-liquid separate phase flow rate in the fluid-mixing by the total mass flow calculation of fluid-mixing then, simultaneously the gas-liquid flow is carried out the temperature and pressure compensation.This combined method only is applicable to measure mixes two-phase fluid uniformly, and two restriction devices fit together the consistance that can not guarantee on the space, therefore two-phase flow flow pattern and procedure parameter in flow process is difficult to be consistent, run counter to easily that combined type measures precondition---promptly there is original reason error in the constant principle of its basic parameter when two-phase fluid flows through each ingredient.

Patent US 5485743, US 5130661, US 6857323, US 6940286, CN99209502.6, CN200680055193.4 etc. have announced employing process tomographic imaging technology measurement polyphasic flow procedure parameter.Process tomographic imaging is made up of the sensor space array, data acquisition and the processing unit that obtain the measured object field information, image reconstruction and thing field parameter extraction unit, the sensor array is set up responsive successively in measurement space under certain mode of operation, by data acquisition and processing unit the signal that reflects detected material field dielectric distribution in the different sensitizing ranges is gathered and handled, use image algorithm to reconstruct the image of reflection dielectric distribution then, adopt certain information processing method to extract required parameter on this basis.Yet chromatography imaging technique does not satisfy industrial application requirements as yet at aspects such as real-time, measuring accuracy and picture qualities, and the quick variation characteristic of polyphasic flow conflicts with the complicacy of tomography image reconstruction algorithm, may cause result of calculation to exist than mistake.

Summary of the invention

The objective of the invention is deficiency at above-mentioned prior art existence, a kind of combined type trans that can more accurately measure the polyphasic flow procedure parameter is provided, provides a kind of the utilization thisly to realize that according to all types of sensor own characteristics signal between sensors is complementary and redundantly realize measuring optimized multiphase flow measurement device simultaneously.Sensor of the present invention and measurement mechanism, a kind of long waist inner cone restriction device and a kind of multi-section electricity sensitive sensor is combined, do not carry out pre-separation or mixing to measuring fluid, realize the polyphasic flow procedure parameter in external phase is from conductive phase to non-conductive phase scope, accurate measurement as a minute phase content (cross section phase content, quality phase content), phase-splitting flow velocity, volumetric flow rate and mass rate, carry out flow pattern identification by the analysis to measure signal, with the optimization measurement result, and can utilize cross-correlation method to test the speed between identical electrodes.Technical scheme of the present invention is as follows:

The long waist inner cone of a kind of multi-section impedance type sensor, be used for the polyphasic flow of the pipeline of flowing through is measured, comprise cone throttling element, contraction pressure drop differential pressure transmitter, permanent crushing differential pressure transmitter, electricity sensitive sensor, described cone throttling element is a kind of long waist inner cone throttling element, by the leading portion cone, constitute for three sections as stage casing column, the back segment cone of cone waist, by the coaxial pipeline center of being fixed in of support, form annular free air space with the tube wall of pipeline; Two pressure ports of described contraction pressure drop differential pressure transmitter, one is arranged on cone throttling element upstream end, and another is arranged on annular free air space place or cone afterbody; Two pressure ports of described permanent crushing differential pressure transmitter are separately positioned on recovery place of cone throttling element upstream and downstream pressure; Described electricity sensitive sensor comprises four groups of electrodes that are distributed in respectively on four different cross sections of annular free air space, every group of electrode is made of electrode in one or more and one or more external electrode, interior electrode is cone throttling element or the electrode that is fixed on cone waist surface, and external electrode is fixed on inner-walls of duct; In four groups of electrodes, there is the structure of two arrays of electrodes all identical, is used to detect the conductivity of polyphasic flow with the spatial disposition mode, it is right to be called resistance electrode, the structure of two arrays of electrodes is all identical with the spatial disposition mode in addition, is used to detect the specific inductive capacity of polyphasic flow, and it is right to be called capacitance electrode.

As preferred implementation, described cone waist is the equal diameter right cylinder, and its length is got 0.1-3 times of internal diameter of the pipeline, equivalent diameter ratio

Be 0.5 to 0.85, wherein, d is the diameter of cone waist, and D is an internal diameter of the pipeline; Constitute the length range of each right electrode of capacitance electrode in the pipeline axial direction, promptly width range is 20mm-50mm, constitutes the length range of each right electrode of resistance electrode in the pipeline axial direction, and promptly width range is 1mm-10mm.

The present invention provides the long waist inner cone of a kind of multi-section impedance type multiphase flow measurement device simultaneously, be used for the polyphasic flow of the pipeline of flowing through is measured, comprise cone throttling element, contraction pressure drop differential pressure transmitter, permanent crushing differential pressure transmitter, electricity sensitive sensor, computing unit, described cone throttling element is a kind of long waist inner cone throttling element, by the leading portion cone, constitute for three sections as stage casing column, the back segment cone of cone waist, by the coaxial pipeline center of being fixed in of support, form annular free air space with the tube wall of pipeline; Two pressure ports of described contraction pressure drop differential pressure transmitter, one is arranged on cone throttling element upstream end, and another is arranged on annular free air space place or cone afterbody; Two pressure ports of described permanent crushing differential pressure transmitter are separately positioned on recovery place of cone throttling element upstream and downstream pressure; Described electricity sensitive sensor comprises four groups of electrodes that are distributed in respectively on four different cross sections of annular free air space, every group of electrode is made of electrode in one or more and one or more external electrode, interior electrode is cone throttling element or the electrode that is fixed on cone waist surface, and external electrode is fixed on inner-walls of duct; In four groups of electrodes, there is the structure of two arrays of electrodes all identical with the spatial disposition mode, be used to detect the conductivity of polyphasic flow, it is right to be called resistance electrode, the structure of two arrays of electrodes is all identical with the spatial disposition mode in addition, is used to detect the specific inductive capacity of polyphasic flow, and it is right to be called capacitance electrode, during measurement by interior electrode of the each gating of computing unit and the external electrode corresponding with it respectively as excitation/potential electrode and ground-electrode, and collection electric signal; Shrink pressure drop and send into computing unit by differential pressure transmitter with permanent crushing.

As preferred implementation, described cone waist is the equal diameter right cylinder, and its length is got 0.1-3 times of internal diameter of the pipeline, equivalent diameter ratio

Be 0.5 to 0.85, wherein, d is the diameter of cone waist, and D is an internal diameter of the pipeline; Constitute the length range of each right electrode of capacitance electrode in the pipeline axial direction, promptly width range is 20mm-50mm, constitutes the length range of each right electrode of resistance electrode in the pipeline axial direction, and promptly width range is 1mm-10mm.

Beneficial effect of the present invention and advantage are as follows:

1, the annular free air space of cone throttling element and duct wall formation carries out rectification to the polyphasic flow fluid-mixing, flow in the circular passage of formation standard, channel inner pressure is stablized and pressure is linear decline along axis, makes the repeatability of measurement and degree of accuracy raising become possibility; Reliable mounting structure flexibly can be changed the cone throttling element of different-diameter ratio according to the different measuring object, with the scope of application of expansion measurement.

2, the present invention is by introducing flow pattern anticipation device or directly adopting electric sensor and the simultaneously-measured advantage of differential pressure (flow) sensor, utilization contains rate and predicts the outcome and carry out classification, identification and the anticipation of flow pattern with the volume forecasting result, when adopting arc-shaped electrode as electric sensor, also can utilize the differentiation that the rate distributed intelligence realizes instantaneous flow pattern that contains of its measurement, adopt the accurate measurement of different computation model implementation procedure parameters according to variations in flow patterns.

3, the polyphasic flow fluid-mixing flows through the cone throttling element and produces in annular free air space and shrink pressure drop Δ p, and produce permanent crushing δ p in pressure recovery place of cone downstream certain distance, adopt contraction pressure drop Δ p and permanent crushing δ p to make differential pressure signal, comprised flowing information more fully.

4, various informativeization of electricity sensitive sensor, as ring electrode, arc-shaped electrode etc., adopting arc-shaped electrode can be the form of many measurement space combinations with the average measurement characteristic changing of ring electrode, has improved the local measurement susceptibility, and then improves overall measurement accuracy; The character variation of electricity sensitive sensor, four cross section electrodes comprise the electrode of the measurement fluid-mixing specific inductive capacity that the electrode of two groups of identical measurement fluid-mixing conductivity is identical with two groups, can measure impedance information simultaneously, the measurement range of expanding unit; The variation of electricity sensitive sensor modes of emplacement, capacitive transducer and electric resistance sensor can be placed at interval, can place in proper order; The energisation mode variation of electricity sensitive sensor, as voltage drive and current excitation etc., internal and external electrode all can be used as exciting electrode.

Description of drawings

The following drawings has been described embodiment chosen of the present invention, is exemplary drawings and non exhaustive or restricted, wherein:

The long waist inner cone of Fig. 1 embodiment of the invention 1 multi-section impedance type multiphase flow measurement device front view;

The long waist inner cone of Fig. 2 embodiment of the invention 1 multi-section impedance type multiphase flow measurement device lateral cross section view;

Fig. 3 (a) is vertical C-C cross section view of conical throttling gear of the present invention; (b) be the vertical view of the embodiment of the invention 1 cone; (c) be the horizontal B-B cross section view of cone;

The vertical view of the sensor of Fig. 4 (a) embodiment of the invention 2 (b) is the horizontal B-B cross section view of device; (c) be vertical A-A cross section view of device; (d) be the horizontal C-C cross section view of device, wherein, interior electrode is four cross section ring electrodes, and dispatch from foreign news agency is four cross sections, 8 arc-shaped electrodes very;

The vertical view of the sensor of Fig. 5 (a) embodiment of the invention 3 (b) is the horizontal B-B cross section view of device; (c) be vertical A-A cross section view of device; (d) be the horizontal C-C cross section view of device, wherein, interior electrode is four cross sections, 8 arc-shaped electrodes, and dispatch from foreign news agency is four cross sections, 8 arc-shaped electrodes very;

The vertical view of the sensor of Fig. 6 (a) embodiment of the invention 4 (b) is the horizontal B-B cross section view of device; (c) be vertical A-A cross section view of device; (d) be the horizontal C-C cross section view of device;

The vertical view of the sensor of Fig. 7 (a) embodiment of the invention 5 (b) is the horizontal B-B cross section view of device; (c) be vertical A-A cross section view of device; (d) be the horizontal C-C cross section view of device, wherein, interior electrode is single wide electrode, and dispatch from foreign news agency is four cross section same widths ring electrodes very;

The computing unit structural drawing that Fig. 8 adopts for the present invention;

Signal in Fig. 9 computing unit takes place and the mode selection module structural drawing;

Signal condition modular structure figure in Figure 10 computing unit;

AD in Figure 11 computing unit gathers and the signal pre-processing module structural drawing;

Figure 12 apparatus of the present invention measuring method process flow diagram;

The number in the figure explanation: the different cross section electrode is used a respectively, b, and c, d distinguishes, a among the label 16-21, b, c, d represent the 16-21 of different cross section electrode.

Embodiment

Below describe in detail making and operate step of the present invention, be intended to describe as embodiments of the invention, is not to be can be manufactured or unique form of utilizing, should comprise within the scope of the invention other embodiment that can realize identical function yet.

Describe the preferred embodiments of the present invention in detail below in conjunction with Figure of description.

1-4 with reference to the accompanying drawings, the preferred embodiments of the present invention 1 comprise that two ends have the pipeline 1 of flange 2, a cone throttling element 7, three pressure ports: upstream pressure port 3, middle pressure port 4, downstream pressure port 5, two transmitters: shrink pressure drop differential pressure transmitter 24, permanent crushing differential pressure transmitter 25, be installed in the electricity sensitive sensor on annular free air space 12 corresponding pipelines 1 and the cone waist 9: external electrode 17, interior electrode 16, computing unit 27 and other accessory structures.Cone throttling element 7 be on the basis of traditional inner cone with throat downstream equal diameter lengthening form cone waist 9 and get, cone throttling element 7 is by support 11 and the support fixture splice 6 coaxial pipe centerline places that are installed in, and can change the cone 7 of different throttling ratios with the expansion measurement range according to measured matter and operating mode, cone throttling element 7 is included in the entrance 8 that the flow direction diameter increases gradually, cone waist 9 that diameter is constant and diameter are decreased to zero outlet section 10 gradually, when polyphasic flow fluid-mixing 13 flows through this cone throttling element 7, one of circulation area experience is dwindled gradually, and the process that enlarges gradually after in certain distance, stablizing, during polyphasic flow fluid-mixing 13 process cone entrances 8, circulation area reduces reposefully, speed is increased regularly, static pressure is corresponding to be reduced, along with circulation area reduces, the rate of change of speed is big more; When fluid flows through cone waist 9 places, owing to inertia effect continues to quicken, the fluid that continues to quicken can be adjusted because of the rectified action of cone throttling element 7 again, flowed in its circular passage that forms standard at annular free air space 12 places.Cone throttling element 7 adopts resistant material (high performance metal material, industrial ceramics or other corrosion-resistant materials) in case the corrosion of fluid stopping body.In cone throttling element 7 upstreams, annular free air space 12 and downstream pressure recover corresponding tube wall pressure port are set, because cone throttling element 7 is coaxially installed in the pipeline 1, when fluid-mixing 13 flows through, can produce with middle pressure port 4 and shrink pressure drop Δ p at the upstream of cone throttling element 7 pressure port 3, produce permanent crushing δ p at upstream pressure port 3 and pressure recovery place downstream pressure port 5, shrink pressure drop transmitter 24 and permanent crushing transmitter 25 by pressure guiding pipe 23 these two pairs of differential pressure signals of collection, the electrical quantity signal that produces is transferred to computing unit 27 by transducer signal line 26.

The electricity sensitive sensor that is embedded in apparatus of the present invention on cone waist 9 and the pipeline 1 can form symmetrical electric field in annular free air space 12, by measure the fluid electrical parameter (as electricity lead, electric capacity, specific inductive capacity etc.) determine that each phase (component) contains rate.The electricity sensitive sensor comprises four groups of electrodes that are distributed on the annular free air space different cross section, there is the structure of two arrays of electrodes all identical in these four groups of electrodes with the spatial disposition mode, be used to detect the conductivity of polyphasic flow, the structure of two arrays of electrodes is all identical with the spatial disposition mode in addition, is used to detect the specific inductive capacity of polyphasic flow; Every group of electrode constitutes by interior electrode and external electrode, and interior electrode is cone throttling element itself or is fixed on cone waist surface that external electrode is fixed on inner-walls of duct.The electrode of two groups of same structures can be realized measurement of correlation.Among the figure, interior electrode 16 is embedded in cone waist 9 top layers, and external electrode 17 is embedded in pipeline 1 inwall top layer, and electrode and the corresponding top layer that is embedded into body maintain an equal level, and promptly electrode can not produce disturbance to polyphasic flow fluid-mixing 13.Electrode 16 is the metal ring electrode in four cross sections, comprise the interior electrode 16a, the 16c that measure the fluid-mixing specific inductive capacity and interior electrode resistance 16b, the 16d of measurement fluid-mixing conductivity, link to each other by separately circuit in the signal wire passage 22 of cone throttling element 7 and support 11 inside and computing unit 27 by terminals 18 separately, signal wire 20; Four cross section external electrodes 17 are the circular metal electrode with interior electrode 16 same widths and thickness, comprise the external electrode 17a, the 17c that measure the fluid-mixing specific inductive capacity and external electrode 17b, the 17d of measurement fluid-mixing conductivity, link to each other by separately circuit in terminals 19 separately, signal wire 21 and the computing unit 27.External electrode 17 is as exciting electrode in the present embodiment, insulation and ground connection between interior electrode 16 and the cone throttling element 7, measure the voltage signal between internal and external electrode, measuring-signal is by signal wire 20,21, be transferred to computing unit 27, with above-mentioned differential pressure signal simultaneous, obtain the polyphasic flow procedure parameter according to computation model, as a minute phase content (cross section phase content, quality phase content), phase-splitting flow velocity, volumetric flow rate and mass rate, then the Long-distance Control interface is arrived in output signal 28 demonstrations or teletransmission, finished the measurement of total system.Measurement mechanism of the present invention is installed in the actual pipeline by flange, and the diameter of concrete pipeline and length is border situation and deciding factually.

Multi-section electrode form and array mode in apparatus of the present invention have diversified characteristics, are 0 ° to 180 ° as electrode center of circle angular region; Electrode width scope 0mm is to L/4 (cone throttling element waist length L); Internal and external electrode can be that identical shaped electrode can be a difformity electrode etc. also, so the electrode structure of this device has various ways, and Fig. 2, Fig. 4-7 has described wherein five kinds of typical array modes, and other array configurations can make up on this basis.

Fig. 2 has described embodiment 1: internal and external electrode is the ring electrode cross section view (electrode structure of preferred embodiment) of same widths, and one in the internal and external electrode as another ground connection of exciting electrode, and energisation mode is current excitation or voltage drive.

Embodiments of the invention 2-5, other structures are all identical with embodiment 1, and difference is that embodiment 2-5 has proposed other several preferred embodiments of electrode structure.

Fig. 4 has described embodiment 2: dispatch from foreign news agency very is distributed in 8 arc-shaped electrodes on four cross sections, comprise the electrode 17a that measures the fluid-mixing specific inductive capacity, the electrode 17b of 17c and measurement fluid-mixing conductivity, 17d, interior electrode is that same widths is distributed in four ring electrodes on the cross section, comprise the electrode 16a that measures the fluid-mixing specific inductive capacity, the electrode 16b of 16c and measurement fluid-mixing conductivity, the vertical view of 16d (a), transverse cross sectional view (b, d), longitudinal profile view (c), electrode 17a wherein, 17c, 16a, 16c is for measuring the electrode of fluid-mixing specific inductive capacity, width is 30mm, electrode 17b, 17d, 16b, 16d is an electrode, and width is 5mm.The structure of electrode, fixed form, signal wire etc. are consistent with interior electrode shown in the embodiment 1 in this array configuration; Each circular arc external electrode 17 all is connected computing unit 27 by terminals 19 separately with signal wire 21.The preferred central angle of external electrode is 11 °, according to experiment conclusion as can be known, is distributed in 4 °-40 ° of 8 arc-shaped electrode central angle ranges of choice on the cross section, and arc-shaped electrode number variable (central angle changes thereupon).One in the internal and external electrode as another ground connection of exciting electrode.Energisation mode is current excitation or voltage drive.

Fig. 5 has described embodiment 3: dispatch from foreign news agency very is distributed in 8 arc-shaped electrodes on four cross sections, comprise the electrode 17a that measures the fluid-mixing specific inductive capacity, the electrode 17b of 17c and measurement fluid-mixing conductivity, 17d, interior electrode is that same widths is distributed in 8 arc-shaped electrodes on four cross sections, comprise the electrode 16a that measures the fluid-mixing specific inductive capacity, the electrode 16b of 16c and measurement fluid-mixing conductivity, the vertical view of 16d (a), transverse cross sectional view (b, d), longitudinal profile view (c), electrode 17a wherein, 17c, 16a, 16c is for measuring the electrode of fluid-mixing specific inductive capacity, width is 30mm, electrode 17b, 17d, 16b, 16d is for measuring the electrode of fluid-mixing conductivity, and width is 5mm.Internal and external electrode number unanimity in this array configuration, and the position is corresponding one by one, electrode 16a, 16b, 16c, 16d in each circular arc are by terminals 18, signal wire 20 link to each other with computing unit 27 by the signal wire passage 22 in cone throttling element 7 and support 11 inside separately; Each circular arc external electrode 17a, 17b, 17c, 17d all are connected computing unit 27 by terminals 19 separately with signal wire 21.The preferred central angle of inside and outside circle arc-shaped electrode is 11 °, according to experiment conclusion as can be known, is distributed in 4 °-40 ° of 8 arc-shaped electrode central angle ranges of choice on the cross section, and arc-shaped electrode number variable (central angle changes thereupon).One in the internal and external electrode as another ground connection of exciting electrode.Energisation mode is current excitation or voltage drive.

Fig. 6 has described embodiment 4; Constitute two groups of right internal and external electrodes of capacitance electrode and be ring electrode, constitute vertical view (a), transverse cross sectional view (b, d), longitudinal profile view (c) that two groups of right internal and external electrodes of resistance electrode are 8 arc-shaped electrodes, wherein, external electrode 17a, the 17c and interior electrode 16a, the 16c that measure the fluid-mixing specific inductive capacity are ring electrode, width is 30mm, external electrode 17b, the 17d and interior electrode 16b, the 16d that measure the fluid-mixing conductivity are 8 arc-shaped electrodes, and width is 5mm.Internal and external electrode number unanimity in this array configuration, and the position is corresponding one by one, interior electrode 16b, 16d of electrode 16a, 16c and each circular arc in the annular is by terminals 18, signal wire 20 link to each other with computing unit 27 by the signal wire passage 22 in cone throttling element 7 and support 11 inside separately; Annular external electrode 17a, 17c and each circular arc external electrode 17b, 17d all are connected computing unit 27 by terminals 19 separately with signal wire 21.The preferred central angle of inside and outside circle arc-shaped electrode is 11 °, according to experiment conclusion as can be known, according to experiment conclusion as can be known, is distributed in 4 °-40 ° of 8 arc-shaped electrode central angle ranges of choice on the cross section, and arc-shaped electrode number variable (central angle changes thereupon).One in the internal and external electrode as another ground connection of exciting electrode.Energisation mode is current excitation or voltage drive.

Fig. 7 has described and implemented 5: dispatch from foreign news agency very is distributed in four same widths ring electrodes on the cross section, comprise capacitive electrode 17a, the 17c of measurement fluid-mixing specific inductive capacity and resistive electrodes 17b, the 17d of measurement fluid-mixing conductivity, interior electrode is that width is vertical view (a), transverse cross sectional view (b, d), the longitudinal profile view (c) of the single wide electrode 16 of L.In this array configuration, electrode 16 in the wide annular is linked to each other with computing unit 27 by the signal wire passage 22 in cone throttling element 7 and support 11 inside by terminals 18, signal wire 20; Annular external electrode 17a, 17b, 17c, 17d all are connected computing unit 27 by terminals 19 separately with signal wire 21.Dispatch from foreign news agency is exciting electrode very, and interior electrode grounding, energisation mode are current excitation or voltage drive.

The computing unit of present embodiment is shown in accompanying drawing 8～11: mainly be made up of signal generation and mode selection module, signal condition module, AD collection and signal pre-processing module, computer bus and CPU or computing machine, as shown in Figure 8.Wherein:

Signal generation and mode selection module concrete structure mainly are made up of circuit such as computer bus, logic control circuit, signal generation apparatus, constant voltage or constant current source and electrode channel selections as shown in Figure 9.Computer bus is mainly finished communicating by letter and data transmission of data acquisition system (DAS) and CPU or computing machine; The logic control circuit major function is that control signal takes place and electrode channel is selected the working forms of circuit, realizes the selection of system incentive strategy and mode of operation, and and signal condition module and AD collection and signal pre-processing module between co-ordination; It is the pumping signal of the controlled various ways of realization frequency that signal generating circuit selects major function, for example single, double polarity pulse signal and sinusoidal signal etc.; Constant voltage or constant-current source circuit adopt voltage control voltage source (VCVS) or voltage control current source (VCCS) scheme, and mainly the pumping signal that signal generating circuit is produced is converted to amplitude and adjustable constant voltage or the current signal of phase place; Electrode channel selects circuit to adopt the digital simulation switch chip, transmits passage according to working method and policy logic control circuit foundation excitation with measuring-signal.

Signal condition module concrete structure mainly is made up of electrode drive circuit, logic control circuit and signal amplification circuit as shown in Figure 10.Electrode drive circuit adopts the analog drive circuit technology, improves the load capacity of system and reduces the influence of spurious signals such as contact resistance, electric capacity and inductance to measured signal; The section selection module is selected the digital simulation switch chip for use, realizes the multi-section alternation by logic control circuit; Amplifying circuit is made of high-precision meter operational amplifier or programmable amplifier chip, but the induced signal that electrode (adjacent electrode) is upward small in the pair cross-section and the transmission signal of differential pressure transmitter amplify the raising signal to noise ratio (S/N ratio).The setting of the logical address of logic control circuit realization amplifying circuit and the selection output of enlargement factor, and the logic communication between responsible and AD collection and signal pre-processing module and signal generation and the mode selection module.

AD collection and signal pre-processing module structure are as shown in Figure 11.Mainly form by AD converter array, digital signal processing and logic control circuit, data storage computer bus etc.The AD converter array circuit adopts the AD conversion chip to constitute, and can convert tested simulating signal and the differential pressure signal of passing back through the signal condition module to digital signal.Digital signal processing and logic control circuit realize digital signal filtering, separate and be in harmonious proportion function such as storage control, and the data after will handling are transferred to CPU or computer module by computer bus.

The data acquisition system (DAS) course of work that the present invention adopts: at first CPU or computer module carry out initialization operation by computer bus to signal generation and mode selection module, comprise the exciting current selection, excitation frequency is selected and excitation/measurement strategies selection etc., and is realized by logic control circuit.Pumping signal is alternately set up responsive respectively through the cross section handover module in each cross section, circular passage, change the differential pressure signal that electrode voltage changes and differential pressure transmitter is passed back that causes by dielectric distribution in the field and pass through the cable parallel transfer to the signal condition module, electric signal after the conditioning enters AD and gathers and signal pre-processing module, finish analog to digital conversion and the digital signal after the conversion is carried out processing such as filtering and demodulation by digital signal processing and logic control circuit control AD chip, effective information after the processing is conveyed into CPU or computing machine by the computer bus interface, combines analysis and the processing of carrying out measurement data with measurement model.

Below multiphase flow measurement method of the present invention is described:

(1). gather two pairs of differential pressure signals that produce by the cone throttling element: shrink pressure drop differential pressure signal Δ p and permanent crushing differential pressure signal δ p;

(2). utilize the electricity sensitive sensor to gather electric signal;

(3). calculate fluid-mixing total volumetric flow rate Q according to cross-correlation method _v

Electric field in the measure annular free air space 12, the time varying signal that 16d/17d, 16b/17b and capacitance electrode is obtained 16c/17c, 16a/17a from resistance electrode has reflected that each phase component of fluid-mixing 13 contains rate and changes, and can disclose some hydrodynamic characteristics relevant with flow pattern.The flow pattern of supposing fluid 13 remained unchanged in short time period, promptly satisfy " solidifying " flow model, when certain disturbance such as bubble in the biphase gas and liquid flow or water droplet, pass through resistance electrode successively and during to 16c/17c, 16a/17a, can produce time varying signal x 16d/17d, 16b/17b and capacitance electrode ₁(t), y ₁(t) and x ₂(t), y ₂(t), utilize cross-correlation method to measure the relevant speed of discrete phase in the fluid 13, wherein cross correlation function R _Xy(τ) be:

$R_{\mathrm{xy}1}\left(\mathrm{\τ}\right)=\underset{T\→\∞}{\lim }\frac{1}{T}{\∫}_0^T{y}_1\left(t\right)x_1(t-\mathrm{\τ})\mathrm{dt},$ $R_{\mathrm{xy}2}\left(\mathrm{\τ}\right)=\underset{T\→\∞}{\lim }\frac{1}{T}{\∫}_0^T{y}_2\left(t\right)x_2(t-\mathrm{\τ})\mathrm{dt}---\left(1\right)$

In the formula:

x ₁(t), x ₂(t) expression resistance electrode time varying signal that 16d/17d and capacitance electrode are produced 16c/17c;

y ₁(t), y ₂(t) expression resistance electrode time varying signal that 16b/17b and capacitance electrode are produced 16a/17a;

τ represents the independent variable of cross correlation function;

Therefore by coherent signal x ₁(t), y ₁(t) in the Fluid Computation 13 from upstream electrode to 16d/17d to the transit time of downstream electrode to 16b/17b, and from upstream electrode to 16c/17c to the transit time of downstream electrode to 16a/17a, also be related function R _Xy1(τ), R _Xy2(τ) the pairing time τ in the peak value of figure (maximal value) position ₀₁, τ ₀₂It is exactly the delay time T between two signals.The big hydrodynamic noise of the capacitance electrode of general large-size to being used in the test fluid 13, as big bubble, the relevant speed that this electrode pair is measured can be thought the relevant speed of gas phase, the right three-dimensional resolving power of the resistance electrode of reduced size is sensitiveer, can measure in the fluid 13 the small flow noise that the random variation by the droplet spatial distribution state causes, the relevant speed that this electrode pair is measured can be thought the relevant speed of liquid phase.So relevant speed V of liquid phase in the fluid-mixing 13 ₁Relevant speed V with gas phase ₂For:

${\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="HDA0000048287510000012.png"\; state="\{\{state\}\}">V</figure-callout>}}_1=\frac{{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HDA0000048287510000012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1}{{\mathrm{\&tau;}}_{01}}$ Or ${\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">V</figure-callout>}}_2=\frac{{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">L</figure-callout>}}_2}{{\mathrm{\&tau;}}_{02}}---\left(2\right)$

In the formula, L ₁, L ₂Be respectively spacing between the conductance type electrode pair two arrays of electrodes and capacitive electrode to the spacing between the two arrays of electrodes, τ ₀₁, τ ₀₂Be respectively signal delay time between the conductance type electrode pair two arrays of electrodes and capacitive electrode to the signal delay time between the two arrays of electrodes.Because flowing of fluid 13 can not meet " solidifying " flow model hypothesis fully, always there are certain difference in relevant speed and real fluid cross section average velocity, therefore introduce speed correction factor K ₁, K ₂,

V=K ₁V ₁+ V _dOr V=K ₂V ₂+ V _d(3)

Wherein:

K ₁, K ₂Be speed correction factor, V _dBe alternate sliding velocity, can unite definite by experimental study and experimental formula;

V is a fluid-mixing average velocity;

Then the fluid-mixing total volumetric flow rate is:

Q _v＝A ₀V (4)

In the formula:

Q _vBe the fluid-mixing total volumetric flow rate;

A ₀Circulation area for annular free air space.

(4). utilize Throttle Principle to calculate and divide phase content;

The total volumetric flow rate formula is put out the expression formula of the total volumetric flow rate of fluid in order in differential pressure signal by differential pressure flowmeter (pressure drop of contraction differential pressure transmitter and permanent crushing differential pressure transmitter are arranged in the measurement mechanism that the present invention adopts, and the differential pressure signal that the present invention selects for use is the measuring-signal that shrinks the pressure drop differential pressure transmitter) and the pipeline:

$Q_v=\frac{\mathrm{\&epsiv;}\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="HDA0000048287510000012.png"\; state="\{\{state\}\}">C</figure-callout>}}_1}{\sqrt{1-{\mathrm{\&beta;}}^4}}{\mathrm{<figure-callout\; id="0"\; label="A"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">A</figure-callout>}}_0\sqrt{\frac{2\mathrm{\&Delta;p}}{{\mathrm{\&rho;}}_m}}---\left(5\right)$

For oil-gas-water three-phase flow, fluid hybrid density ρ _mCan be expressed as:

ρ _m＝α _oρ _o+α _wρ _w+α _gρ _g (6)

In the formula: C ₁For shrinking pressure drop Δ p is the efflux coefficient that differential pressure signal calibrates;

ρ _o, ρ _w, ρ _gBe oil phase density, water density, density of gas phase;

α _o, α _w, α _gBe cross section oil content, cross section water percentage, void fraction;

Simultaneous formula (4), (5), (6) obtain hybrid density ρ _mAnd shrink the expression formula between the differential pressure Δ p:

${\mathrm{\&alpha;}}_o{\mathrm{\&rho;}}_p+{\mathrm{\&alpha;}}_w{\mathrm{\&rho;}}_w+{\mathrm{\&alpha;}}_g{\mathrm{\&rho;}}_g=\frac{2{(\mathrm{\&epsiv;}\&CenterDot;C_1)}^2\mathrm{\&Delta;p}}{V(1-{\mathrm{\&beta;}}^4)}---\left(7\right)$

For the gas of oil product, water and known static pressure and the temperature determined, can think the oil phase density p _o, the water density p _wAnd density of gas phase ρ _gKnown, and known

α _o+α _w+α _g＝1 (8)

Therefore wherein contain rate and can draw fluid hybrid density ρ in the cross section of a certain phase if record oil gas water three phase _m

(5). analyze differential pressure signal and electric signal, carry out classification, identification and the anticipation of flow pattern, judging object fluid external phase is conductive phase (water) or non-conductive phase (gas phase or oil phase), right according to the corresponding potential electrode of the different choice of external phase then, if external phase is gas phase or oil phase, utilize capacitance electrode that the voltage signal of 16a/17a and 16c/17c is calculated; If external phase is water then utilizes resistance electrode that the voltage signal of 16b/17b and 16d/17d is calculated.

The general step of flow pattern identification is: at first extract the eigenwert that can reflect variations in flow patterns from measurement data, utilize sorting algorithm that eigenwert is sorted out identification then, such as support vector machine, artificial neural network etc.The present invention is that example is carried out flow pattern identification with the support vector machine method,

Concrete steps are as follows:

1, extracts image data eigenwert makeup time sequence in 5 seconds, from time series, extract three kinds of statistical nature composition characteristic vectors

${\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="HDA0000048287510000012.png"\; state="\{\{state\}\}">T</figure-callout>}}_1=\left[\begin{array}{ccc}\stackrel{\&OverBar;}{x}& S& \mathrm{SK}\end{array}\right],$

Time series mean value Represented the average energy that electric signal or differential pressure signal comprised of electricity sensitive sensor collection:

$\stackrel{\&OverBar;}{x}=\frac{1}{n}\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{x}_i---\left(9\right)$

Wherein n is the eigenwert quantity in the time series, x _iBe single V _mValue.

Seasonal effect in time series standard deviation (S), reacted the degree of scatter of measuring-signal:

$S=\sqrt{\frac{1}{n-1}\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{(x_i-\stackrel{\&OverBar;}{x})}^2}---\left(10\right)$

Seasonal effect in time series gradient (SK), reacted the seasonal effect in time series inclined degree:

$\mathrm{SK}=\frac{n}{(n-1)(n-2)}\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{\left(\frac{x_i-\stackrel{\&OverBar;}{x}}{S}\right)}^3---\left(11\right)$

2, support vector machine (SVM) realizes distance minimization between class distance maximization and the class by setting up a lineoid, can be used as sorter and realizes flow pattern identification.The optimal classification function is

$f\left(x\right)=\mathrm{sgn}\{({\mathrm{\&omega;}}^{*}\&CenterDot;x)+b^{*}\}=\mathrm{sgn}\{\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{a}_i^{*}{y}_{i}K(x_i\&CenterDot;x)+b^{*}\}---\left(12\right)$

In the formula, sgn () is-symbol function, ω ^*Be the normal vector of lineoid, b ^*Be the threshold value of classification, Be optimum solution, y _iBe constraint condition, K (x _iX) be kernel function; Select kernel function according to actual needs.

3, with the input of proper vector, the data that collect are classified as SVM.The target of flow pattern identification of the present invention is water quality type flow pattern, makings type flow pattern and oily type flow pattern three major types, to support vector machine of every kind of flow pattern structure, output y _i∈ 1,1}, (i=1,2,3), then the output of 3 support vector machine is one 3 dimensional vectors, whether each representation in components sample to should flow pattern, (1 ,-1 ,-1) expression water quality type flow pattern, (1,1 ,-1) expression makings type flow pattern, the oily type flow pattern of (1 ,-1,1) expression.Select radially basic kernel function for use

Wherein ζ gets 0.05, and the support vector machine that trains can realize the identification of convection.

(6). utilize electric method to calculate each phase content.

Introduce electrical parameter measuring method measurement cross section and contain rate, comprise two kinds of electrical methods among the present invention, the one, by capacitance electrode the voltage signal between 16a/17a or the 16c/17c is calculated the specific inductive capacity of fluid-mixing and calculates the cross section phase content; The 2nd, by resistance electrode the voltage signal between 16b/17b or the 16d/17d is calculated the conductivity of fluid-mixing and calculates the cross section phase content.Gather the electrical signal of the electricity sensitive sensor in each cross section simultaneously, according to the flow pattern of step (five) differentiate result's (external phase whether conduct electricity) selection wherein a kind of measured value of method carry out subsequent treatment, so whether the present invention is not conducted electricity by continuous phase of multiphase flow to influence.Concrete principle is as follows: the electrical quantity of fluid 13 (as electricity lead, electric capacity, specific inductive capacity etc.) depend on each mutually shared ratio of fluid-mixing, and can set up each phase content and the relation of mixing electrical quantity by some computation models, as the electrical quantity in the Boyle model can by in the fluid-mixing each minute the phase fluid specific inductive capacity function representation.Discrete phase 15 is to be distributed in the liquid phase of being made up of profit two-phase fluid-mixing in the continuous gas phase 14, and then the specific inductive capacity of fluid-mixing 13 can use H-B (H-Bnon) formula to calculate:

$\sqrt{{\mathrm{\&epsiv;}}_m}={\mathrm{\&phi;}}_g\sqrt{{\mathrm{\&epsiv;}}_g}+(1-{\mathrm{\&phi;}}_g)({\mathrm{\&phi;}}_w\sqrt{{\mathrm{\&epsiv;}}_w}+{\mathrm{\&phi;}}_o\sqrt{{\mathrm{\&epsiv;}}_o})---\left(13\right)$

In the formula:

ε _o, ε _w, ε _g, ε _mBe respectively the specific inductive capacity of oil phase, water, gas phase, fluid-mixing;

φ _o, φ _w, φ _gThe volume that is respectively oil phase, water, gas phase contains rate;

The polyphasic flow middle section contains rate α and is difficult to direct measurement, and the average external volume of general available measuring section contains rate φ and replaces.Wherein the specific inductive capacity of oil phase and water can obtain by tabling look-up or demarcating, because the fluid-mixing specific inductive capacity is proportional to the electric capacity between internal and external electrode, and the electric capacity between internal and external electrode is proportional to the voltage magnitude between internal and external electrode, therefore by measuring capacitance electrode can calculate fluid-mixing to the voltage signal between 16a/17a or the 16c/17c specific inductive capacity, by simultaneous formula (7), (8), (13), and then the cross section that obtains oil gas water three phase contains rate α _o, α _w, α _gAnd total volumetric flow rate Q _v

When the water percentage in the fluid-mixing 13 was too high, the use of capacitance method was subjected to certain limitation, but electricity consumption this moment is led as tested electrical quantity.Because the gas phase conductivity is approximately zero, and liquid phase is a conducting medium, so the fluid mixed conductivity depends primarily on the phase content of liquid phase and distribution mutually.According to Maxwell resistivity approximation theory, then the conductivity of fluid-mixing 13 is:

${\mathrm{\&sigma;}}_m=\frac{2{\mathrm{\&alpha;}}_l}{3-{\mathrm{\&alpha;}}_{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">l</figure-callout>}}}\frac{2{\mathrm{\&alpha;}}_w}{3-{\mathrm{\&alpha;}}_w}{\mathrm{\&sigma;}}_w---\left(14\right)$

In the formula:

α _l, α _wBe liquid holdup and cross section water percentage;

σ _m, σ _wBe respectively oil gas water mixed conductivity and water conductivity;

Because the voltage magnitude between mixed conductivity and internal and external electrode is inversely proportional to, therefore, can calculates the conductivity of fluid-mixing, and then obtain cross section water percentage α by the voltage signal between measuring resistance electrode pair 16b/17b or the 16d/17d _wBy simultaneous formula (7), (8), (14), and then the cross section that obtains oil gas water three phase contains rate α _o, α _w, α _gAnd total volumetric flow rate Q _v

The definition that contains rate according to volume can calculate each phase volume flow of oil gas water:

Q _vo＝φ _oQ _v

Q _vw＝φ _wQ _v (15)

Q _vg＝φ _gQ _v

In the formula:

φ _o, φ _w, φ _gFor oil phase, water, gaseous phase volume contain rate;

Q _Vo, Q _Vw, Q _Vg, Q _vBe oil phase, water, gas phase volume flow rate and total volumetric flow rate;

Each phase content is according to the phase velocity definition:

$V_o=\frac{Q_{\mathrm{vo}}}{{\mathrm{\&alpha;}}_{\mathrm{<figure-callout\; id="0"\; label="o\; A"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">o</figure-callout>}}{A}_{}{}_0}$

$V_w=\frac{Q_{\mathrm{vw}}}{{\mathrm{\&alpha;}}_w{A}_0}---\left(16\right)$

$V_g=\frac{Q_{\mathrm{vg}}}{{\mathrm{\&alpha;}}_{\mathrm{<figure-callout\; id="0"\; label="g\; A"\; filenames="HDA0000048287510000022.png"\; state="\{\{state\}\}">g</figure-callout>}}{A}_{}{}_0}$

In the formula:

V _o, V _w, V _gBe oil phase flow velocity, aqueous phase flow rate, gas phase flow velocity;

α _o, α _w, α _gBe cross section oil content, cross section water percentage, void fraction.

Claims (9)

1. the long waist inner cone of multi-section impedance type sensor, be used for the polyphasic flow of the pipeline of flowing through is measured, comprise cone throttling element, contraction pressure drop differential pressure transmitter, permanent crushing differential pressure transmitter, electricity sensitive sensor, described cone throttling element is a kind of long waist inner cone throttling element, by the leading portion cone, constitute for three sections as stage casing column, the back segment cone of cone waist, by the coaxial pipeline center of being fixed in of support, form annular free air space with the tube wall of pipeline; Two pressure ports of described contraction pressure drop differential pressure transmitter, one is arranged on cone throttling element upstream end, and another is arranged on annular free air space place or cone afterbody; Two pressure ports of described permanent crushing differential pressure transmitter are separately positioned on recovery place of cone throttling element upstream and downstream pressure; Described electricity sensitive sensor comprises four groups of electrodes that are distributed in respectively on four different cross sections of annular free air space, every group of electrode is made of electrode in one or more and one or more external electrode, interior electrode is cone throttling element itself or the electrode that is fixed on cone waist surface, and external electrode is fixed on inner-walls of duct; In four groups of electrodes, there is the structure of two arrays of electrodes all identical, is used to detect the conductivity of polyphasic flow with the spatial disposition mode, it is right to be called resistance electrode, the structure of two arrays of electrodes is all identical with the spatial disposition mode in addition, is used to detect the specific inductive capacity of polyphasic flow, and it is right to be called capacitance electrode.

2. the long waist inner cone of multi-section impedance type according to claim 1 sensor, it is characterized in that: described cone waist is the equal diameter right cylinder, its length is got 0.1-3 times of internal diameter of the pipeline, equivalent diameter ratio

Be 0.5 to 0.85, wherein, d is the diameter of cone waist, and D is an internal diameter of the pipeline.

3. the long waist inner cone of multi-section impedance type according to claim 1 multiphase flow measurement device is characterized in that: constituting each right electrode of capacitance electrode is 20mm-50mm at the length range of pipeline axial direction; Constituting each right electrode of resistance electrode is 1mm-10mm at the length range of pipeline axial direction.

4. the long waist inner cone of multi-section impedance type multiphase flow measurement device, be used for the polyphasic flow of the pipeline of flowing through is measured, comprise cone throttling element, contraction pressure drop differential pressure transmitter, permanent crushing differential pressure transmitter, electricity sensitive sensor, computing unit, described cone throttling element is a kind of long waist inner cone throttling element, by the leading portion cone, constitute for three sections as stage casing column, the back segment cone of cone waist, by the coaxial pipeline center of being fixed in of support, form annular free air space with the tube wall of pipeline; Two pressure ports of described contraction pressure drop differential pressure transmitter, one is arranged on cone throttling element upstream end, and another is arranged on annular free air space place or cone afterbody; Two pressure ports of described permanent crushing differential pressure transmitter are separately positioned on recovery place of cone throttling element upstream and downstream pressure; Described electricity sensitive sensor comprises four groups of electrodes that are distributed in respectively on four different cross sections of annular free air space, every group of electrode is made of electrode in one or more and one or more external electrode, interior electrode is cone throttling element itself or the electrode that is fixed on cone waist surface, and external electrode is fixed on inner-walls of duct; In four groups of electrodes, there is the structure of two arrays of electrodes all identical with the spatial disposition mode, be used to detect the conductivity of polyphasic flow, it is right to be called resistance electrode, the structure of two arrays of electrodes is all identical with the spatial disposition mode in addition, is used to detect the specific inductive capacity of polyphasic flow, and it is right to be called capacitance electrode, during measurement by interior electrode of the each gating of computing unit and the external electrode corresponding with it respectively as excitation/potential electrode and ground-electrode, and collection electric signal; Shrink pressure drop and send into computing unit by differential pressure transmitter with permanent crushing.

5. the long waist inner cone of multi-section impedance type according to claim 4 multiphase flow measurement device, it is characterized in that: described cone waist is the equal diameter right cylinder, its length is got 0.1-3 times of internal diameter of the pipeline, equivalent diameter ratio

Be 0.5 to 0.85, wherein, d is the diameter of cone waist, and D is an internal diameter of the pipeline.

6. according to any long waist inner cone of the described multi-section impedance type multiphase flow measurement device of claim 4 to 5, it is characterized in that: constituting each right electrode of capacitance electrode is 20mm-50mm at the length range of pipeline axial direction; Constituting each right electrode of resistance electrode is 1mm-10mm at the length range of pipeline axial direction.

7. according to any long waist inner cone of the described multi-section impedance type multiphase flow measurement device of claim 4 to 6, it is characterized in that: one or more groups electrode wherein, interior electrode is cone throttling element itself or is the ring electrode that is fixed on cone waist surface that this electrode is as ground-electrode; Dispatch from foreign news agency is ring electrode or at least one arc-shaped electrode very.

8. according to any long waist inner cone of the described multi-section impedance type multiphase flow measurement device of claim 4 to 7, it is characterized in that: one or more groups electrode wherein, interior electrode is ring electrode or at least one arc-shaped electrode, and dispatch from foreign news agency is very as the ring electrode of ground-electrode.

9. according to any long waist inner cone of the described multi-section impedance type multiphase flow measurement device of claim 4 to 8, it is characterized in that: one or more groups electrode wherein, interior electrode and external electrode are arc-shaped electrode, and number is one or more.

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