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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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Phase-Based Optical Flow Method with Optimized Parameter Settings for Enhancing Displacement Measurement Adaptability
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作者 Zhaoxin Peng Menglian Liu +2 位作者 Zhiliang Wang Wei Liu Xian Wang 《Open Journal of Applied Sciences》 2024年第5期1165-1184,共20页
To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizi... To enhance the applicability and measurement accuracy of phase-based optical flow method using complex steerable pyramids in structural displacement measurement engineering applications, an improved method of optimizing parameter settings is proposed. The optimized parameters include the best measurement points of the Region of Interest (ROI) and the levels of pyramid filters. Additionally, to address the issue of updating reference frames in practical applications due to the difficulty in estimating the maximum effective measurement value, a mechanism for dynamically updating reference frames is introduced. Experimental results demonstrate that compared to representative image gradient-based displacement measurement methods, the proposed method exhibits higher measurement accuracy in engineering applications. This provides reliable data support for structural damage identification research based on vibration signals and is expected to broaden the engineering application prospects for structural health monitoring. 展开更多
关键词 Displacement measurement Phase-Based Optical flow Optimized Parameter Setting
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A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures
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作者 Yan-Xiao He Shang-Xu Wang +9 位作者 Gen-Yang Tang Chao Sun Hong-Bing Li San-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng Dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期162-181,共20页
Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and... Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure conditions.Calibration with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2000,10^(6)]Hz.The Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent effects.Under dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the sandstone.In particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective pressure.In addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion. 展开更多
关键词 Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow
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Socio-scientific quantification of the comprehensive benefits of debris flow mitigation measures for villages in western Sichuan, China
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作者 DENG Ting XU Pei +4 位作者 LI Ming LU Yafeng WANG Yukuan LI Zhengyang SHRAVAN Kumar Ghimire 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1598-1612,共15页
Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the speci... Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the specific disasterreduction effects of these measures and their economic,social and ecological benefits is yet to be performed.The western region of Sichuan Province frequentlysuffers from geohazards such as debris flow, and thegovernment has adopted many mitigation measures.This study assessed the benefits of debris flowmitigation measures and identified the key influencingfactors via a field-based study conducted in 81 villagesin western Sichuan province, China. A framework forthe evaluation of the benefits of rural debris flowmitigation measures was constructed andquantitatively evaluated using a survey. Snowballsampling was performed to recruit 81 village leadersand 468 farmers. The results showed that managementand engineering measures were the main methodsused to mitigate debris flow;ecological measures wereauxiliary. The average satisfaction scores of farmers forthese three types of measures were 4.07, 3.90, and 3.56,respectively (as measured on a five-point Likert scale).In contrast, in terms of the benefits of these mitigationmeasures, only a small proportion of villages (11.11%)obtained a high level of comprehensive benefits fromthe debris flow mitigation measures, while the majority(88.89%) received medium to low-level benefits. Toimprove this situation, we further studied and foundthat the main factors that restricted villages fromachieving high-level comprehensive benefits were theunpredictable nature of debris flows, labour forceoutflow and remoteness. Effective control measures, agood economic environment and strong governmentassistance were reported as crucial factors forimproving these comprehensive benefits. This studyprovides socio-scientific references for decisionmakingon rural debris flow mitigation measures while keeping villages at the centre of economic development. 展开更多
关键词 Mitigation measures Comprehensive benefit evaluation Debris flow Mountain development Rural areas
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Simultaneous measurement of velocity profile and liquid film thickness in horizontal gas–liquid slug flow by using ultrasonic Doppler method 被引量:1
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作者 Lusheng Zhai Bo Xu +1 位作者 Haiyan Xia Ningde Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期323-340,共18页
Horizontal gas-liquid two-phase flows widely exist in chemical engineering,oil/gas production and other important industrial processes.Slug flow pattern is the main form of horizontal gas-liquid flows and characterize... Horizontal gas-liquid two-phase flows widely exist in chemical engineering,oil/gas production and other important industrial processes.Slug flow pattern is the main form of horizontal gas-liquid flows and characterized by intermittent motion of film region and slug region.This work aims to develop the ultrasonic Doppler method to realize the simultaneous measurement of the velocity profile and liquid film thickness of slug flow.A single-frequency single-channel transducer is adopted in the design of the field-programmable gate array based ultrasonic Doppler system.A multiple echo repetition technology is used to improve the temporal-spatial resolution for the velocity profile.An experiment of horizontal gas-liquid two-phase flow is implemented in an acrylic pipe with an inner diameter of 20 mm.Considering the aerated characteristics of the liquid slug,slug flow is divided into low-aerated slug flow,high-aerated slug flow and pseudo slug flow.The temporal-spatial velocity distributions of the three kinds of slug flows are reconstructed by using the ultrasonic velocity profile measurement.The evolution characteristics of the average velocity profile in slug flows are investigated.A novel method is proposed to derive the liquid film thickness based on the instantaneous velocity profile.The liquid film thickness can be effectively measured by detecting the position and the size of the bubbles nearly below the elongated gas bubble.Compared with the time of flight method,the film thickness measured by the Doppler system shows a higher accuracy as a bubble layer occurs in the film region.The effect of the gas distribution on the film thickness is uncovered in three kinds of slug flows. 展开更多
关键词 Gas–liquid flow Complex fluids measurement Ultrasonic Doppler Velocity profile Liquid film thickness
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A Novel Method for Wet Gas Flow Measurements Based on an Over-Reading Principle
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作者 Jinjing Zhang Jia Li 《Fluid Dynamics & Materials Processing》 EI 2023年第2期303-313,共11页
A novel method to measure the flow rate in a wet gas is presented.Due to the presence of liquid,there is a deviation in the measurement of the gas volume flow rate obtained with standard vortex flow-meters.The propose... A novel method to measure the flow rate in a wet gas is presented.Due to the presence of liquid,there is a deviation in the measurement of the gas volume flow rate obtained with standard vortex flow-meters.The proposed method is based on a correction factor determined through the application of an over-reading approach to a bluff body in mist flow.The correction factor is obtained from the slip velocity ratio,i.e.,the ratio of droplet velocity to gas velocity,based on the analysis of the fluid velocity distribution in the pipeline section.It also takes into account relevant theoretical arguments.It is shown that the predicted results fit the experimental results well. 展开更多
关键词 Over-reading flow measurement correction algorithm
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Uncertainty analysis of flow rate measurement for multiphase flow using CFD 被引量:9
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作者 Joon-Hyung Kim Uk-Hee Jung +2 位作者 Sung Kim Joon-Yong Yoon Young-Seok Choi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第5期698-707,共10页
The venturi meter has an advantage in its use,because it can measure flow without being much affected by the type of the measured fluid or flow conditions.Hence,it has excellent versatility and is being widely applied... The venturi meter has an advantage in its use,because it can measure flow without being much affected by the type of the measured fluid or flow conditions.Hence,it has excellent versatility and is being widely applied in many industries.The flow of a liquid containing air is a representative example of a multiphase flow and exhibits complex flow characteristics.In particular,the greater the gas volume fraction(GVF),the more inhomogeneous the flow becomes.As a result,using a venturi meter to measure the rate of a flow that has a high GVF generates an error.In this study,the cause of the error occurred in measuring the flow rate for the multiphase flow when using the venturi meter for analysis by CFD.To ensure the reliability of this study,the accuracy of the multiphase flow models for numerical analysis was verified through comparison between the calculated results of numerical analysis and the experimental data.As a result,the Grace model,which is a multiphase flow model established by an experiment with water and air,was confirmed to have the highest reliability.Finally,the characteristics of the internal flow Held about the multiphase flow analysis result generated by applying the Grace model were analyzed to find the cause of the uncertainty occurring when measuring the flow rate of the multiphase flow using the venturi meter.A phase separation phenomenon occurred due to a density difference of water and air inside the venturi,and flow inhomogeneity happened according to the flow velocity difference of each phase.It was confirmed that this flow inhomogeneity increased as the GVF increased due to the uncertainty of the flow measurement. 展开更多
关键词 Multiphase flow measurement Numerical analysis Venturi meter Gas volume fraction(GVF) Uncertainty Multiphase flow model Grace model
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Machine Vision Based Measurement of Dynamic Contact Angles in Microchannel Flows 被引量:5
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作者 Valtteri Heiskanen Kalle Marjanen Pasi Kallio 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第4期282-290,共9页
When characterizing flows in miniaturized channels, the determination of the dynamic contact angle is important. By measuring the dynamic contact angle, the flow properties of the flowing liquid and the effect of mate... When characterizing flows in miniaturized channels, the determination of the dynamic contact angle is important. By measuring the dynamic contact angle, the flow properties of the flowing liquid and the effect of material properties on the flow can be characterized. A machine vision based system to measure the contact angle of front or rear menisci of a moving liquid plug is described in this article. In this research, transparent flow channels fabricated on thermoplastic polymer and sealed with an adhesive tape are used. The transparency of the channels enables image based monitoring and measurement of flow variables, including the dynamic contact angle. It is shown that the dynamic angle can be measured from a liquid flow in a channel using the image based measurement system. An image processing algorithm has been developed in a MATLAB environment. Images are taken using a CCD camera and the channels are illuminated using a custom made ring light. Two fitting methods, a circle and two parabolas, are experimented and the results are compared in the measurement of the dynamic contact angles. 展开更多
关键词 digital image processing machine vision MICROFLUIDICS microchannel flow dynamic contact angle image based measurement
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Flow measurement and parameter optimization of right-angled flow passage in hydraulic manifold block 被引量:7
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作者 HU Jian-jun CHEN Jin +1 位作者 QUAN Ling-xiao KONG Xiang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第4期852-864,共13页
This study was conducted to investigate the flow field characteristics of right-angled flow passage with various cavities in the typical hydraulic manifold block.A low-speed visualization test rig was developed and th... This study was conducted to investigate the flow field characteristics of right-angled flow passage with various cavities in the typical hydraulic manifold block.A low-speed visualization test rig was developed and the flow field of the right-angled flow passage with different cavity structures was measured using 2D-PIV technique.Numerical model was established to simulate the three-dimensional flow field.Seven eddy viscosity turbulence models were investigated in predicting the flow field by comparing against the particle image relocimetry(PIV)measurement results.By defining the weight error function K,the S-A model was selected as the appropriate turbulence model.Then,a three-factor,three-level response surface numerical test was conducted to investigate the influence of flow passage connection type,cavity diameter and cavity length-diameter ratio on pressure loss.The results show that the Box-Benhnken Design(BBD)model can predict the total pressure loss accurately.The optimal factor level appeared in flow passage connection type II,14.64 mm diameter and 67.53%cavity length-diameter ratio.The total pressure loss decreased by 11.15%relative to the worst factor level,and total pressure loss can be reduced by 64.75%when using an arc transition right-angled flow passage,which indicates a new direction for the optimization design of flow passage in hydraulic manifold blocks. 展开更多
关键词 flow measurement particle image relocimetry right-angled flow passage parameter optimization
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Field Measurements of Influence of Sand Transport Rate on Structure of Wind-sand Flow over Coastal Transverse Ridge 被引量:10
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作者 DONG Yuxiang S L NAMIKAS +1 位作者 P A HESP MA Jun 《Chinese Geographical Science》 SCIE CSCD 2008年第3期255-261,共7页
The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Prov... The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The measurement results show that, on the conditions of approximate wind velocities and same surface materials and environments, some changes happen to the structure of wind-sand flow with the increase of total sand transport rate on the crest of coastal transverse ridge. First, the sand transport rates of layers at different heights in the wind-sand flow increase, with the maximum increase at the height layer of 4-8cm. Second, the ratios of sand trans-port rates of layers at different heights to total sand transport rate decrease at the low height layer (0-4cm), but increase at the high height layer (4-60cm). Third, the distribution of the sand transport rate in the wind-sand flow can be expressed by an exponential function at the height layer of 0-40cm, but it changes from power function model to ex-ponential function model in the whole height layer (0-60cm) and changes into polynomial function model at the height layer of 40-60cm with the increase of total sand transport rate. Those changes have a close relationship with the limit of sand grain size of wind flow transporting and composition of sand grain size in the wind-sand flow. 展开更多
关键词 sand transport rate coastal transverse ridge structure of wind-sand flow field measurement
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Liquid holdup measurement with double helix capacitance sensor in horizontal oil-water two-phase flow pipes 被引量:5
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作者 翟路生 金宁德 +1 位作者 高忠科 王振亚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期268-275,共8页
This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity... This paper presents the characteristics of a double helix capacitance sensor for measurement of the liquid holdup in horizontal oil–water two-phase flow. The finite element method is used to calculate the sensitivity field of the sensor in a pipe with 20 mm inner diameter and the effect of sensor geometry on the distribution of sensitivity field is presented. Then, a horizontal oil–water two-phase flow experiment is carried out to measure the response of the double helix capacitance sensor, in which a novel method is proposed to calibrate the liquid holdup based on three pairs of parallel-wire capacitance probes. The performance of the sensor is analyzed in terms of the flow structures detected by mini-conductance array probes. 展开更多
关键词 Horizontal oil–water two-phase flow Liquid holdup measurement Double helix capacitance sensor flow pattern
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The Flow Measurement of Multiphase Flow Based on the Conductance Sensor 被引量:5
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作者 Rui-Rong Dang Dong-Sheng Zhao +1 位作者 Li-Pin Li Guang Yin 《Modern Instrumentation》 2012年第4期35-40,共6页
Oil-gas-water three-phase flow in the pipe is commonly encountered in the petroleum and nature gas industry. Its flow patterns are complex and always changeable, so it’s difficult to be measured and is becoming one o... Oil-gas-water three-phase flow in the pipe is commonly encountered in the petroleum and nature gas industry. Its flow patterns are complex and always changeable, so it’s difficult to be measured and is becoming one of the most important subjects. Moreover, most of the oil fields in China are in such a high water fraction period that measures must be taken to meet the needs of the actual production. A conductance sensor which is widely used in the measurements of oil-water two-phase flow is used to measure the flow rate of the three-phase flow based on the research of the characteristics and the correlation theory, and a new technical solution which is suitable for measuring the oil-gas-water three-phase flow is established. A series of tests demonstrate that it’s feasible to use the conductance sensor in the measurements of oil- gas-water three-phase flow. 展开更多
关键词 CORRELATION measurement Technology CONDUCTANCE SENSOR flow measurement THREE-PHASE flow
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Spectral measurements of hypervelocity flow in an expansion tunnel 被引量:2
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作者 C.K.Yuan K.Zhou +2 位作者 Y.F.Liu Z.M.Hu Z.L.Jiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第1期24-31,I0002,共9页
Atmospheric reentry vehicles and planetary probes fly through the atmosphere at hypervelocity speed. At such speed, there is a significant proportion of heat load to the vehicle surface due to radiative heating. Accur... Atmospheric reentry vehicles and planetary probes fly through the atmosphere at hypervelocity speed. At such speed, there is a significant proportion of heat load to the vehicle surface due to radiative heating. Accurate prediction needs a good knowledge of the radiation spectrum properties. In this paper, a high-speed camera and spectrograph coupled to an intensified charge-coupled device have bee n impleme nted to inv estigate the rad i at io n flow over a semi-cylinder model. The experiments were carried out in the JF16 expansi on timnel with secondary shock velocity of 7.9 km·s^-1. Results show that the emissio n spectrum comprises several atomic lines and molecular band systems. We give detailed data of the radiation spectrum, shock shape, shock detached distance and radiation intensity varying with space and wavelength. This valuable experimental dataset will be helpful to validate computational fluid dynamics codes and radiation models, which equates to increased prediction accuracy of radiation heating. Also, some suggestions for spectral measurement in hypervelocity flow field were list in the end. 展开更多
关键词 SPECTRAL measurement HYPERVELOCITY flow RADIATION EXPANSION TUNNEL
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Void fraction measurement and calculation model of vertical upward co-current air-water slug flow 被引量:1
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作者 Teng Wang Miao Gui +2 位作者 Jinle Zhao Qincheng Bi Tao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第11期178-198,共21页
The focus of this paper is on the measurement and calculation model of void fraction for the vertical upward co-current air-water slug flow in a circular tube of 15 mm inner diameter. High-speed photography and optica... The focus of this paper is on the measurement and calculation model of void fraction for the vertical upward co-current air-water slug flow in a circular tube of 15 mm inner diameter. High-speed photography and optical probes were utilized, with water superficial velocity ranging from 0.089 to 0.65 m·s^(-1)and gas superficial velocity ranging from 0.049 to 0.65 m·s^(-1). A new void fraction model based on the local parameters was proposed, disposing the slug flow as a combination of Taylor bubbles and liquid slugs. In the Taylor bubble region, correction factors of liquid film thickness Cδand nose shape CZ*were proposed to calculate aTB. In the liquid slug region, the radial void fraction distribution profiles were obtained to calculate aLS, by employing the image processing technique based on supervised machine learning. Results showed that the void fraction proportion in Taylor bubbles occupied crucial contribution to the overall void fraction. Multiple types of void fraction predictive correlations were assessed using the present data. The performance of the Schmidt model was optimal, while some models for slug flow performed not outstanding. Additionally, a predictive correlation was correlated between the central local void fraction and the cross-sectional averaged void fraction, as a straightforward form of the void fraction calculation model. The predictive correlation showed a good agreement with the present experimental data, as well as the data of Olerni et al., indicating that the new model was effective and applicable under the slug flow conditions. 展开更多
关键词 Slug flow Gas-liquid flow Void fraction measurement Optical probe Model
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Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows 被引量:3
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作者 Li-Xing Zhou.Yang Liu.Yi Xu Department of Engineering Mechanics,Tsinghua University,100084 Beijing,China Marine Engineering College,Dalian Maritime University,116026 Dalian,China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第4期494-501,共8页
In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer (PDPA) and simulated the system behavior by ... In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer (PDPA) and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes (RANS) model and a large-eddy simulation (LES). The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups (30μm, 50μm, and 95μm) and the gasparticle velocity correlation for 30μm and 50μm particles. From the measurements, theoretical analysis, and simulation, it is found that the two-phase velocity correlation of sudden-expansion flows, like that of jet flows, is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements, theoretical analysis, and numerical simulation all lead to the above-stated conclusions. Quantitatively, the results of the LES are better than those of the RANS model. 展开更多
关键词 PDPA measurement - Simulation Two-phasevelocity correlation Sudden expansion gas-particle flows
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The Measurement of Oil,Gas and Water Flowrates in Three-Phase Slug Flow
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作者 蔡继勇 陈听宽 罗毓珊 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第4期37-43,共7页
Three-sphase flow invo1ving oil-water two immiscible liquids and gas which is often foundin the fields of petroleum production has been studied in this paper.A new method with thecombination of a horizontal tube,a dow... Three-sphase flow invo1ving oil-water two immiscible liquids and gas which is often foundin the fields of petroleum production has been studied in this paper.A new method with thecombination of a horizontal tube,a downward flow vertica1 tube and an orifice to measure theflowrates is presented.In this method the frictional pressure drop in the downward vertical tube isreplaced by that in the horizontal tube,the void fraction is derived from the gravitational pressuredrop,then the volume fraction of the individual phase can also be obtained.The individual flowratescan be calculated when the water fraction is known.This method is applicable for many kinds ofoil-wells to measure the flowrates of crude oil,natural gas and water.Compared with other methods,the presented method involves fewer measuring parameters.The experimental results proved quitegood accuracy of the method,with measurement deviation within 10%,and reliable results wereobtained under high Dressure conditions. 展开更多
关键词 measurement flowrate THREE-PHASE flow SLUG flow
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Heat Transfer Method for Solid Flow Rate Measurement in Gas-Solid Two Phase Flow
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作者 袁竹林 卢作基 《Journal of Southeast University(English Edition)》 EI CAS 1997年第2期74-78,共5页
A new method for measuring the solid flow rate in gas solid two phase flow is introduced in this paper. An electrically heated probe was put in a gas solid two phase flow. For certain solid particles, the flow medi... A new method for measuring the solid flow rate in gas solid two phase flow is introduced in this paper. An electrically heated probe was put in a gas solid two phase flow. For certain solid particles, the flow media with different velocities and concentrations of particles produced different effects on heat transfer with the probe. The solid flow rate can be measured according to the intensity of heat transfer. Experiments were made on a pilot pneumatic conveying device. Research results prove that the method works effectively and reliably. 展开更多
关键词 gas SOLID two PHASE flow measurement HEAT TRANSFER
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VISUALIZATION AND MEASUREMENT OF VORTEX FLOW IN SPINNING SHELL-CASE
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作者 张道生 《Journal of China Textile University(English Edition)》 EI CAS 1993年第3期58-63,共6页
The characteristics of a flow in spinning devices are one of the fundamental problems innew-type spinning.In this paper the vortex flow in interior of the shell-case was studied by usingexperimental methods,which incl... The characteristics of a flow in spinning devices are one of the fundamental problems innew-type spinning.In this paper the vortex flow in interior of the shell-case was studied by usingexperimental methods,which include flow visualization and laser doppler techniques.The flow sur-vey by measurement has been compared with that photographed by flow visualization method,andshows a fairly good conformity.The results of experiments are similar to those by numericalevaluation. 展开更多
关键词 flow VISUALIZATION VELOCITY measurement Laser DOPPLER technique votex flow flow patterns.
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INVESTIGATION OF PULSED-WIRE TECHNIQUE FOR WALL PARAMETERS MEASUREMENT IN SEPARATED FLOWS
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作者 Liao Yufeng, Xu Cheng(Mechanical Engineering Institute, Nanjing University of Scienceand Technology, Nanjing, 210094, China) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1997年第2期98-103,共6页
A pulsed-wire wall probe measurement system was developed in this paper,which can be used for measuring wall Parameters in separated flow- The operating princi-ple was described and the way of probe calibration was gi... A pulsed-wire wall probe measurement system was developed in this paper,which can be used for measuring wall Parameters in separated flow- The operating princi-ple was described and the way of probe calibration was given. Wall parameters of back-ward-facing and forward-facing step flow were measured,and the wall nows structure andcharacters were revealed. 展开更多
关键词 separated flow measurement pulse heating wall parameters pulsed-wire wall probe
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A New Method for Measurement of Helium Mass Flow Rate in the Cryogenic System of TORE SUPRA
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作者 欧阳峥嵘 Pascal Reynaud 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2825-2827,共3页
The TORE SUPRA Tokamak was built by EURATOM-CEA association. The NbTi conductor of superconducting coils is inserted in a tight enclosure filled with pressurized superfluid helium of 0.125 MPa at 1.8 K. The thick casi... The TORE SUPRA Tokamak was built by EURATOM-CEA association. The NbTi conductor of superconducting coils is inserted in a tight enclosure filled with pressurized superfluid helium of 0.125 MPa at 1.8 K. The thick casing is cooled to 4.5 K by 1.8 MPa in 4.5 K supercritical helium circulation. Around this thick casing, a 80 K thermal shield protects the parts at very low temperatures from the thermal radiation, which is cooled by pressurized helium at 80 K and 1.8 MPa. A new measurement method for helium mass flow rate of 80 K shield and 4.5 K casing is described in this paper. The commissioning was done on the two helium loops of the cryoplant: the supercritical 4.5 K thick casing and 80 K shields. The purpose is to improve control of the 4.5 K and 80 K refrigeration loops. 展开更多
关键词 mass flow rate VALVE measurement HELIUM
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