CN110186522B - Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic - Google Patents

Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic Download PDF

Info

Publication number
CN110186522B
CN110186522B CN201910474178.2A CN201910474178A CN110186522B CN 110186522 B CN110186522 B CN 110186522B CN 201910474178 A CN201910474178 A CN 201910474178A CN 110186522 B CN110186522 B CN 110186522B
Authority
CN
China
Prior art keywords
calculating
gas phase
gas
volume flow
vortex street
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201910474178.2A
Other languages
Chinese (zh)
Other versions
CN110186522A (en
Inventor
王超
李金霞
丁红兵
孙宏军
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tianjin University
Original Assignee
Tianjin University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tianjin University filed Critical Tianjin University
Priority to CN201910474178.2A priority Critical patent/CN110186522B/en
Publication of CN110186522A publication Critical patent/CN110186522A/en
Application granted granted Critical
Publication of CN110186522B publication Critical patent/CN110186522B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
    • G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
    • G01F1/32—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow using swirl flowmeters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus

Abstract

The invention relates to a method for moisture over-reading compensation and flow measurement by combining vortex street amplitude characteristics, which comprises the following steps: collecting pressure p, temperature T and vortex street time sequence signals s (T) output by a piezoelectric sensor; calculation of gas Density ρgAnd liquid density ρp(ii) a Extracting the frequency f of the vortex street signalVSAnd amplitude AVS(ii) a Calculating the apparent gas phase volume flow Q without reading correctiong,apparentAs gas phase volume flow rate QgIterating the initial value; and (3) iteratively calculating until convergence: calculating the gas phase volume flow QgCorresponding superficial gas phase velocity UsgCalculating the signal amplitude of single-phase gas and calculating the liquid drop loading phipCalculating an overreading factor OR, and calculating overreading compensated moisture gas phase volume flow. The final gas phase volume flow rate Q in the wet gas is obtainedgAnd droplet loading phip。

Description

Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic
Technical Field
The invention belongs to the field of gas-liquid two-phase flow measurement, and relates to a moisture over-reading compensation and flow measurement method combining vortex street amplitude characteristics.
Background
Moisture flow widely exists in the natural gas industry, and accurate measurement of the moisture flow has important influence on pipeline transportation and trade settlement, and is directly related to environmental protection, energy management and full utilization thereof [1 ]. When the gas velocity is high, the annular mist flow is the most predominant wet gas flow type, in which the liquid phase exists in the form of entrained droplets and a liquid film on the wall [2 ]. Vortex shedding flowmeters are widely used for online measurement of moisture because of their robustness, economy, high range ratio, and low pressure loss. However, when the conventional single-phase vortex shedding flowmeter is applied to moisture measurement, a small amount of liquid phase in the moisture affects the coefficient of the vortex shedding meter, so that the measured gas phase flow rate is high (over-reading, OR), and a measurement error of 20% can be caused at most [3 ]. In order to improve the measurement accuracy of the vortex shedding flowmeter in moisture, the over-reading phenomenon needs to be accurately modeled and reasonably corrected.
In the literature [4], aiming at the problem of non-uniform overreading correlation under different pressure and medium working conditions, the mass loading of liquid drops in an aqueous phase is a main factor influencing the overreading of a vortex street through theoretical calculation. However, the correction of overreading requires that the droplet mass flow or droplet mass fraction in the wet gas is known, typically measured by microwave, ray and isovelocity sampling methods [5 ]. These methods are complex to operate, costly and difficult to achieve continuous accurate measurements. At present, accurate measurement of the moisture flow is difficult to realize only by one vortex street flowmeter.
Patent 201810644726.7 has designed a multi-parameter adjustable fog flow experimental system, and patent 201810226454.9 has given an annular flow liquid film collection and metering device, and patent 201810232606.6 has provided an annular flow liquid film separation and mass metering method.
Reference to the literature
[1]Mehdizadeh P,Marrelli J,Ting V C,“Wet gas metering:trends in applications and technical developments,”in Proc.SPE Annu.Tech.Conf,San Antordo,TX,USA,2002,pp.1–14.
[2]T.Oshinowo and M.E.Charles,“Vertical two-phase flow part I.Flow pattern correlations,”Can.J.Chem.Eng.,vol.52,no.1,pp.25–35,1974.
[3]R.Steven,“Wet gas metering,”Ph.D.dissertation,Dept.Mech.Eng.Univ.Strathclyde,Scotland U.K.,2001.
[4]J.X.Li,C.Wang,H.B.Ding,Z.X,Zhang and H.J.Sun,“EMD and spectrum-centrobaric-correction-based analysis of vortex street characteristics in annular mist flow of wet gas”,IEEE Trans.Instrum.Meas.,vol.37,no.5,pp.1150–1160,May 2018.
[5]ASME,ASME MFC-19G-2008,Wet gas flowmetering guideline.American Society of Mechanical Engineers,USA,2008.
Disclosure of Invention
The invention aims to provide a moisture flow measuring method which can eliminate the problem of measurement over-reading caused by a liquid phase by using only one vortex street flowmeter based on the frequency and amplitude characteristics of a vortex street piezoelectric sensor in moisture. The technical scheme of the invention is as follows:
a moisture overreading compensation and flow measurement method combining vortex street amplitude characteristics utilizes frequency and amplitude characteristics of a vortex street piezoelectric sensor in moisture to perform moisture overreading compensation and flow measurement, and comprises the following steps:
1) and collecting pressure p, temperature T and a vortex street time sequence signal s (T) output by the piezoelectric sensor.
2) Calculating the gas density ρ by p and T, respectivelygAnd liquid density ρp(ii) a Extracting the frequency f of the vortex street signalVSAnd amplitude AVS。
3) Calculating the apparent gas phase volume flow Q without reading correction according to the formula (1)g,apparentAs gas phase volume flow rate QgInitial value of iteration
Qg,apparent＝3600fVS/Kv (1)
Wherein, KvMeter coefficient (m) for vortex shedding flowmeter in single phase gas-3)。
4) Calculating the gas phase volume flow Q according to equation (2)gCorresponding superficial gas phase velocity Usg
Usg＝4Qg/πD2 (2)
Wherein D is the nominal diameter of the pipeline.
5) Calculating the signal amplitude A in the single-phase gas according to the formula (3)0(unit: mV)
Figure BDA0002080725160000021
6) According to the vortex street signal characteristic amplitude A in the formula (4)VSWith droplet loading phipCalculating the liquid drop loading phip
Figure BDA0002080725160000022
7) Calculating the over-reading factor OR according to equation (5)
OR＝1+271.08φpρg/ρp (5)
8) Calculating the overreading compensated moisture gas phase volume flow according to the formula (6)
Qg＝Qg,apparent/OR (6)
9) If | Qg-Qg,lastIf the absolute value is less than or equal to a positive real number which is small enough, the iteration is ended, otherwise, the calculated gas phase volume flow Q isgAnd performing 4-8 steps of calculation again as an initial value of the next iteration until convergence.
10) The final gas phase volume flow rate Q in the wet gas is obtainedgAnd droplet loading phip。
Drawings
FIG. 1: signal acquisition flow chart
FIG. 2: pattern of flow pattern of mist
FIG. 3: graph of overreading-drop loading relation
FIG. 4: relation graph of vortex street signal amplitude in single phase and apparent gas velocity and gas phase density
FIG. 5: non-dimensional vortex street signal amplitude-liquid drop loading relation graph in moisture
FIG. 6: iterative algorithm flow chart
FIG. 7: comparison graph of predicted value and actual value of gas phase volume flow in moisture
FIG. 8: gas phase volume flow prediction error distribution diagram in moisture
Detailed Description
The invention will now be further described with reference to the accompanying drawings and examples.
This example is a specific implementation of the moisture over-read compensation and flow measurement method that combines the vortex street amplitude characteristics. The pressure p of the wet gas working condition is 270-440 kPa, and the gas phase volume flow Qg＝9～17m3H, mass flow of liquid phase ml＝1.7～17kg/h。
The signal acquisition flow chart is shown in the attached figure 1: collecting working condition pressure p, working condition temperature T and vortex street sequence number s (T), wherein s (T) is obtained by collecting a piezoelectric sensor: the method comprises the steps that a piezoelectric probe converts a flowing signal into an electric signal, a hardware circuit amplifies charges and voltages of an original signal, band-pass filtering is conducted (f is 200-2500 Hz), then data collection is conducted through an NI-USB collection card, the sampling frequency is 20kHz, the number of sampling points is 131072, display and storage are conducted through Labview software, and therefore a vortex timing sequence signal s (t) is obtained.
The vortex shedding flowmeter is a speed type flowmeter and measures vortex shedding frequency fVSThe fluid volume flow can be obtained
Figure BDA0002080725160000031
Wherein, Kv(＝4St0/πD2d) Meter coefficient (m) for vortex shedding flowmeter in single phase gas-3). D is the nominal diameter of the pipeline, D is the incident flow width of the generator, St0The gas is a Strouhal number under the working condition of single-phase gas, and is constant within a certain Reynolds number range. In this example, St0＝0.251,d＝4.2mm，D＝15mm,Kv＝338182.4m-3。
In the wet gas flow, the existence of a small amount of liquid phase enables the measured gas phase volume flow Q in the process of measuring the wet gas by using the vortex shedding flowmeterg,apparentHigher than actual gas flow QgThis phenomenon is called "over-reading". For correcting the vortex street overreading, a correction coefficient OR with the dimension of 1 is introduced and expressed as
Figure BDA0002080725160000032
Wherein St is the Storehal number in the wet gas, and St is fVS·d/Usg，UsgIs the gas phase apparent flow velocity, Usg＝4Qg/πD2。
According to the document [4]]Conclusion of the study, droplet loading φpIs the main factor affecting the over-read OR. Mist of moistureThe flow pattern is shown in figure 2: the liquid phase flows at a low velocity partly in the form of a liquid film on the tube wall and partly in the form of discrete droplets entrained by the gas flow.
Defining a droplet mass loading parameter phip
Figure BDA0002080725160000033
Wherein m ispAnd mLFRepresenting the mass flow of the droplets and the liquid film, m, respectivelylAnd mgRepresenting the mass flow of the liquid and gas phases, respectively.
To accurately measure the gas phase flow in a two-phase flow of moisture, the over-read OR must be accurately modeled and reasonably corrected. The patent provides a moisture overreading compensation and flow measurement method combining vortex street amplitude characteristics.
The over-reading and amplitude characteristics of the vortex street sensor in moisture are first modeled. By utilizing a multi-parameter adjustable mist flow experiment system in patent 201810644726.7, and annular flow liquid film collecting devices and mass metering methods provided in patents 201810226454.9 and 201810232606.6, the liquid drop loading phi under different liquid phase mass loading phi and different pressures p is measuredp。
And then calibrating the correlation coefficient in the model correlation. Over-reading OR with phipCan be obtained by the method shown in FIG. 3
Figure BDA0002080725160000034
Under single-phase gas working condition, the signal amplitude A0(unit: mV) and apparent gas velocity UsgAnd gas phase density ρgIs shown in FIG. 4, having
Figure BDA0002080725160000041
Dimensionless vortex street signal amplitude A*＝AVS/A0Is shown in FIG. 5, having
Figure BDA0002080725160000042
Based on the above modeling and calibration results in moisture regarding the vortex street frequency and amplitude characteristics, a moisture measurement model can be obtained, summarized as follows:
Figure BDA0002080725160000043
Figure BDA0002080725160000044
Figure BDA0002080725160000045
Figure BDA0002080725160000046
Figure BDA0002080725160000047
based on the modeling and calibration results, the wet gas over-reading compensation and flow measurement combining the vortex street amplitude characteristic are performed, as shown in fig. 6, and the method is as follows:
1) and collecting pressure p, temperature T and a vortex street time sequence signal s (T) output by the piezoelectric sensor.
2) Calculating the gas density ρ by p and T, respectivelygAnd liquid density ρp(ii) a Extracting the frequency f of the vortex street signalVSAnd amplitude AVS。
3) Calculating the apparent gas phase volume flow Q without reading correction according to the formula (1)g,apparentAs gas phase volume flow rate QgInitial value of iteration
Qg,apparent＝3600fVS/Kv (7)
Wherein, KvMeter coefficient (m) for vortex shedding flowmeter in single phase gas-3)。
4) Calculating the gas phase volume flow Q according to equation (2)gCorresponding superficial gas phase velocity Usg
Usg＝4Qg/πD2 (8)
Wherein D is the nominal diameter of the pipeline.
5) Calculating the signal amplitude A in the single-phase gas according to the formula (3)0(unit: mV)
Figure BDA0002080725160000051
6) According to the vortex street signal characteristic amplitude A in the formula (4)VSWith droplet loading phipCalculating the liquid drop loading phip
Figure BDA0002080725160000052
7) Calculating the over-reading factor OR according to equation (5)
OR＝1+271.08φpρg/ρp (11)
8) Calculating the overreading compensated moisture gas phase volume flow according to the formula (6)
Qg＝Qg,apparent/OR (12)
9) If | Qg-Qg,lastIf the absolute value is less than or equal to a positive real number which is small enough, the iteration is ended, otherwise, the calculated gas phase volume flow Q isgAnd performing 4-8 steps of calculation again as an initial value of the next iteration until convergence.
10) The final gas phase volume flow rate Q in the wet gas is obtainedgAnd droplet loading phip。
In order to verify the above proposed method for compensating and measuring the flow rate of the wet gas over-reading combined with the amplitude characteristic of the vortex street, the real value and the predicted value of the gas phase volume flow under different conditions are shown in fig. 7. The error distribution of the predicted value and the true value is shown in fig. 8, where the error PE (%) ═ predicted value-true value)/true value × 100. In moisture measurement, the prediction errors of the gas phase volume flow are within +/-1.5%, and the average absolute error is 0.37%, which indicates that the model prediction precision is high.
The invention provides a method for moisture over-reading compensation and flow measurement by combining vortex street amplitude characteristics by modeling the frequency characteristics and the amplitude characteristics of a vortex street flowmeter in moisture. The invention provides a measuring method which can realize accurate measurement of wet gas flow only by one vortex shedding flowmeter without other complicated and expensive liquid flow measuring devices and measuring methods, and is simple, economic and high in prediction precision.

Claims (1)

1. A moisture overreading compensation and flow measurement method combining vortex street amplitude characteristics utilizes frequency and amplitude characteristics of a vortex street sensor in moisture to perform moisture overreading compensation and flow measurement, and comprises the following steps:
1) pressure acquisitionpTemperature ofTAnd vortex street time sequence signal output by piezoelectric sensors(t)；
2) By passingpAndTseparately calculating gas density
Figure DEST_PATH_IMAGE002
And density of liquid
Figure DEST_PATH_IMAGE004
(ii) a Extracting frequency of vortex street signalf VS Sum amplitudeA VS ；
3) Calculating the apparent gas phase volume flow without reading correction according to the formula (1)Q g,apparentAnd as the gas phase volume flowQ g Initial value of iteration of, i.e.Q g = Q g,apparent
Figure DEST_PATH_IMAGE008
（1）
Wherein the content of the first and second substances,K v meter coefficient (m) for vortex shedding flowmeter in single phase gas-3)；
4) Calculating the gas phase volume flow according to equation (2)Q g Corresponding superficial gas phase velocityU sg
Figure DEST_PATH_IMAGE011
（2）
Wherein the content of the first and second substances,Dis the nominal diameter of the pipeline;
5) calculating the signal amplitude of single-phase gas according to the formula (3)A 0
Figure DEST_PATH_IMAGE014
（3）
6) Calculating the liquid drop loading amount according to the relation between the vortex street signal characteristic amplitude and the liquid drop loading amount in the formula (4)
Figure DEST_PATH_IMAGE016
Figure DEST_PATH_IMAGE019
（4）
7) Calculating the over-reading factor OR according to equation (5)
Figure DEST_PATH_IMAGE022
（5）
8) Calculating the overreading compensated moisture gas phase volume flow according to the formula (6)Q g
Figure DEST_PATH_IMAGE025
（6）
9) If it is not
Figure DEST_PATH_IMAGE027
If the real number is small enough, the iteration is ended, otherwise, the calculated gas phase volume flow is calculatedQ g Performing the calculation of the steps 4) -8) again as an initial value of the next iteration until convergence;
the final gas phase volume flow in the wet gas is obtained from the last iteration calculation resultQ g And droplet loading
Figure 333035DEST_PATH_IMAGE016
。
CN201910474178.2A 2019-05-31 2019-05-31 Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic Expired - Fee Related CN110186522B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910474178.2A CN110186522B (en) 2019-05-31 2019-05-31 Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910474178.2A CN110186522B (en) 2019-05-31 2019-05-31 Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic

Publications (2)

Publication Number Publication Date
CN110186522A CN110186522A (en) 2019-08-30
CN110186522B true CN110186522B (en) 2020-12-11

Family

ID=67719661

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910474178.2A Expired - Fee Related CN110186522B (en) 2019-05-31 2019-05-31 Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic

Country Status (1)

Country Link
CN (1) CN110186522B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111649789B (en) * 2020-04-16 2022-03-29 天津大学 Wet air flow measuring method integrating vortex street frequency and convection characteristic
CN112926767A (en) * 2021-01-27 2021-06-08 天津大学 Annular fog flow gas phase apparent flow velocity prediction method based on particle swarm BP neural network
CN112857481B (en) * 2021-01-29 2024-04-05 中国民航大学 Vortex street moisture split-phase flow measurement method based on liquid film thickness modeling
CN113049047B (en) * 2021-01-29 2022-12-02 天津大学 Newton iteration-based vortex street moisture split-phase flow measurement method
CN112945318B (en) * 2021-01-29 2022-12-06 天津大学 Moisture split-phase flow measuring method based on liquid film thickness measurement and vortex shedding flowmeter

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1967159A (en) * 2006-11-13 2007-05-23 浙江大学 Method for measuring flux and volume air rate of gas-liquid two-phase bubble flow
CN101578503A (en) * 2006-08-28 2009-11-11 因万西斯系统股份有限公司 Wet gas measurement
US9188471B2 (en) * 2014-04-22 2015-11-17 King Fahd University Of Petroleum And Minerals Two-phase flow sensor using cross-flow-induced vibrations
US9424674B2 (en) * 2014-04-01 2016-08-23 Saudi Arabian Oil Company Tomographic imaging of multiphase flows
CN106768117A (en) * 2017-02-20 2017-05-31 天津大学 A kind of dryness of wet steam flow double parameter measuring method
CN108469281A (en) * 2018-01-18 2018-08-31 天津大学 Two-phase Research on vortex signal processing based on EMD and Spectrum Correction

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101578503A (en) * 2006-08-28 2009-11-11 因万西斯系统股份有限公司 Wet gas measurement
CN1967159A (en) * 2006-11-13 2007-05-23 浙江大学 Method for measuring flux and volume air rate of gas-liquid two-phase bubble flow
US9424674B2 (en) * 2014-04-01 2016-08-23 Saudi Arabian Oil Company Tomographic imaging of multiphase flows
US9188471B2 (en) * 2014-04-22 2015-11-17 King Fahd University Of Petroleum And Minerals Two-phase flow sensor using cross-flow-induced vibrations
CN106768117A (en) * 2017-02-20 2017-05-31 天津大学 A kind of dryness of wet steam flow double parameter measuring method
CN108469281A (en) * 2018-01-18 2018-08-31 天津大学 Two-phase Research on vortex signal processing based on EMD and Spectrum Correction

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Flow rate measurement of low GVF gas-liquid two-phase flow with a V-Cone meter;Xuebo Zheng,et al.;《Experimental Thermal and Fluid Science》;20180228;第91卷;全文 *
Operational range of a Gas-Solid Vortex Unit;Maximilian Friedle,et al;《Powder Technology》;20181031;第338卷;全文 *
基于涡街流量传感器的湿气测量方法研究;张磊;《中国优秀硕士学位论文全文数据库 信息科技辑》;20110415;全文 *

Also Published As

Publication number Publication date
CN110186522A (en) 2019-08-30

Similar Documents

Publication Publication Date Title
CN110186522B (en) Moisture overreading compensation and flow measurement method combining vortex street amplitude characteristic
JP4469337B2 (en) Coriolis flow meter diagnostic device and diagnostic method
US7881884B2 (en) Flowmeter array processing algorithm with wide dynamic range
CN110186521B (en) Vortex street moisture over-reading compensation and flow measurement method based on wavelet ridge feature extraction
US8892371B2 (en) Wet gas measurement
CN110726444B (en) Wet gas flow metering method and device based on Coriolis mass flowmeter
CN107655533A (en) A kind of Ultrasonic Wave Flowmeter signal processing method and system based on backward energy integration
CN112945318B (en) Moisture split-phase flow measuring method based on liquid film thickness measurement and vortex shedding flowmeter
CN101900589B (en) Air-entrainment liquid flow measuring method based on mass flowmeter
CN102928026B (en) Method of obtaining integrated transient void fraction by utilizing local transient void fraction
CN113049047B (en) Newton iteration-based vortex street moisture split-phase flow measurement method
Zhang et al. Mathematical model of time difference for Coriolis flow sensor output signals under gas-liquid two-phase flow
CN112580183A (en) Method for accurately controlling real-time flow of online learning water pump model
CN114459674B (en) Dynamic calibration method and system for amplitude-frequency characteristics of high-frequency pressure sensor
KR101813804B1 (en) Estimation method of flow characteristic
CN110793585B (en) Wet air flow online measurement method and device based on V cone pressure loss ratio segmentation characteristic
CN112857481B (en) Vortex street moisture split-phase flow measurement method based on liquid film thickness modeling
CN204730893U (en) A kind of integrated iteration flowmeter
CN202836690U (en) Volume correction instrument indication error calibration standard device
WO2020206733A1 (en) Wet gas flow meter based on resonance and differential pressure measurement
CN111649789B (en) Wet air flow measuring method integrating vortex street frequency and convection characteristic
CN117629326A (en) Method for measuring moisture flow of small-pipe-diameter hydrogen loop
CN114777855A (en) Vortex street moisture split-phase flow measuring method based on acceleration detection
CN201413167Y (en) Differential pressure type vortex mass flow meter
CN104713631B (en) The detection method of bulk sound velocity in a kind of oil well

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20201211

Termination date: 20210531

CF01 Termination of patent right due to non-payment of annual fee