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In this paper, we propose a portable intrinsically safe, intelligent electromagnetic flowmeter for the application of coal mines and provide a detailed description of its working principle. In terms of hardware circuit design, several important modules, including electromagnetic flow rate sensor, excitation circuit, core control circuit, signal conditioning circuit, and air traffic control detection circuit, were analyzed and designed in sequence. It adopts a high-performance, low-power MCU STM32407ZET6 and high-precision chips, ensuring measurement accuracy and reducing power consumption. The excitation method using low-frequency rectangular waves dynamically adjusts the sampling interval time, further prolonging the battery life. Finally, the performance of the electromagnetic flowmeter was measured, and the experimental data showed that the measured flow rate was basically linear with the output voltage. The relative indication error of the electromagnetic flowmeter was within 0.3%, and the repeatability fluctuated within the range of 0.03%. The flowmeter has good measurement accuracy, which is suitable for long-term use in coal mining environments. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the measured flow rates are more than 10% lower than the actual injection flow rates when the electromagnetic flowmeters were used in the field to test the layered polymer injection wells. The calibration experiments of electromagnetic flowmeters with tap water and polymer solutions as the flow medium were carried out respectively. The response laws of electromagnetic flowmeters in tap water and polymer solutions with different concentration and viscosity were analyzed and compared. It is pointed out that the change of flow state will cause the change of response instrument constant of electromagnetic flowmeters. The scientific and reasonable explanation was given for the large measurement deviation of electromagnetic flowmeters in the layered polymer injection wells. Furthermore, a new calibration method was proposed to calculate the measured flow rates of layered polymer injection wells by using the calibration equation obtained from the measured data onto laminar flow state of electromagnetic flowmeters in tap water. And the calibration efficiency of this calibration method can be improved more than 30 times. The laboratory experiment error analysis and field experiment error analysis show that the proposed new calibration method of the electromagnetic flowmeter for flow rate measurement of layered polymer injection wells is effective and feasible, and well meets the actual demand of production. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Engineering Science / Gongcheng Kexue Yu Jishu is the property of Advanced Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The declining supply of available groundwater resources is increasing the importance of extraction wells. To maximize the yield of extraction wells, the operators do not always respect the sustainable use of groundwater resources. These efforts can affect water quality and impact the service life of an extraction well, mainly through the clogging process. As part of the INV-FLOW project, an apparatus for evaluating the functionality of an extraction well by measuring the vertical water flow through its screen and filter was designed and tested. The apparatus consists of two electromagnetic induction flowmeters, two pneumatic seals, and a pump with the possibility of regulation. After an initial laboratory verification of the fundamental concept, the apparatus was successfully tested in real conditions. Two extraction wells, HJ-3 and HJ-4, intended for water supply to an agricultural production plant, were measured at a pilot site in the Czech Republic using the INV-FLOW apparatus. Although the HJ-3 extraction well is at the end of its service life, the HJ-4 extraction well is a newly installed well. In the new extraction well, HJ-4, a high proportion of water flowing through the gravel pack relative to the total pumping flow (93–97%) was measured using the INV-FLOW apparatus at different pumping rates. In the case of the HJ-3 extraction well, screen and filter clogging contributed significantly to the limited water flow through the gravel pack. In the most affected parts of the extraction well (15–20 m b.g.l.), the proportion of water flowing through the gravel pack relative to the total pumping flow ranged from 10 to 20%. The pilot tests confirmed the functionality of the apparatus and the possibility of using it to evaluate the degree of clogging and incrustation of an extraction well. The pilot tests thus demonstrated the usability of the INV-FLOW apparatus. The extraction well operator can assess the level of clogging or incrustation of the extraction well and decide on the need for the rehabilitation of an extraction well, or the termination of its operation. [ABSTRACT FROM AUTHOR]

Tracing groundwater flow is of vital importance for managing water resources and understanding the natural water cycle. However, it is a challenge to make accurate measurements of groundwater flow due to its extremely low velocity. A new electromagnetic flowmeter has been developed to conduct non-invasive groundwater flow velocity measurements. In the setup, a customized trapezoidal current source was connected to a 1 m $\times $ 1 m square coil to generate a strong vertical magnetic field. Two electrodes were used to sense the potential difference caused by water flowing through the magnetic field. A simulation has been developed based on Faraday’s law to evaluate the flow signal under an idealized condition. Two different lab environments have been built for testing the device: an artificial mini-aquifer and a rolling gantry. The measurements show that the flow signal, in practice, generated by the slow-moving water was orders of magnitude smaller than the inductive and capacitive interferences in the system. A linear signal processing model has been developed, allowing the flow signal to be extracted from the measured results. The results show good agreement with simulation and a strong correlation between the flow speed and the processed flow signal, having an $R^{2}$ coefficient of 0.94. [ABSTRACT FROM AUTHOR]

The uniformity of the excitation magnetic field is an important factor affecting the measurement accuracy of the electromagnetic flowmeter and its adaptability to different flow states of the complex multiphase flow. The main purpose of this paper is to improve the measurement accuracy of electromagnetic flowmeter by improving the uniformity of magnetic field excitation of electromagnetic flowmeter sensor. Firstly, an evaluation index system based on area weight magnetic field deviation degree is established, and the concept of flow state adaptability is put forward. According to this evaluation system, the excitation structure of the conventional electromagnetic flowmeter sensor is improved and optimized, and an excitation model with high uniformity is designed. Meanwhile, the ANSYS software is used for numerical simulation, and normalized standard deviation is used to compare between the new and the traditional electromagnetic flowmeter models. Finally, according to the requirements of the index function, the magnetic pole detection angle of the improved excitation model is simulated and analyzed, and the optimal magnetic pole detection angle is determined to be 45°. On this basis, a new electromagnetic flowmeter is designed for complex multiphase flow at oil wellhead. The field test proves that the measurement error of this flowmeter can reach less than 5%. Compared with the traditional electromagnetic flowmeter, the measurement accuracy has been greatly improved. [ABSTRACT FROM AUTHOR]

An electromagnetic flowmeter (EMF) can be used to measure the speed of slurry fluid. In this paper, according to Maxwell's equations and the dB/dt vortex electric field, a step excitation scheme is proposed. The original excitation process of the primary excitation current rise time is divided into a two-step excitation process. Without increasing the excitation current rise time, the equivalent excitation frequency is increased by increasing the primary dB/dt. This method can enhance the EMF's ability to overcome slurry noise. The paper analyzes the design parameters of the step excitation scheme and designs the software and hardware. After that, the paper compares the step excitation scheme with the three-value rectangular wave excitation scheme based on wavelet transform signal processing. Experiments show that the step excitation EMF has a lower steady-state fluctuation rate when measuring mortar and has a stronger ability to overcome slurry noise. Additionally, the step excitation EMF and Yokogawa AXF 040G EMF are compared experimentally. Through flow calibration, clean water measurement, mortar measurement and dynamic response experiment, it is verified that the step excitation EMF has the ability to enhance the resistance to slurry noise at the same excitation frequency.

The liquid filling control system with PLC + high-speed counting module has disadvantages of low filling efficiency and poor filling accuracy. The research group analyzed the approach principle and the realization process for high-efficiency and high-accuracy liquid filing control system, and based on the characteristics of high-speed and parallel processing of FPGA (field programmable gate array) control chip, carried out the high-speed collection, filtering, counting and comparing in parallel multiway for the flow ratepulse data to realize the control of the filling valves in multichannels. Combined with the flexibility of MCU software, it can realize the high-efficiency communication with HMI terminal and real time data exchange. After the commissioning of liquid filling control system, a stable flow rate curve and a steady filling volume curve were obtained. The industrial application and verification show that the control system achieves the design purpose of improving production efficiency and filling accuracy. [ABSTRACT FROM AUTHOR]

The electromagnetic flow meter (EMF) is one of the most suitable flowmeter for slurry measurement. It is an important research point of electromagnetic flowmeter to overcome slurry noise in slurry measurement. The main approach to overcome slurry noise is to modify the excitation method and to improve the signal processing method. The novelty of this paper is the first study on the mechanism of excitation switching process to overcome slurry noise. The vortex electric field generated during excitation switching is theoretically analyzed and simulated based on Maxwell’s equations. In order to evaluate the effectiveness of the vortex electric field to overcome the slurry noise, an experiment based on the step excitation signal is proposed. The results of the slurry noise power spectrum show that the increase of the excitation switching process can effectively suppress the slurry noise. The experimental results are consistent with the simulation results. On this basis, the stepwise excitation EMF was developed. Comparison results with conventional three-value excitation EMF show that increasing of excitation switch can effectively suppress slurry noise in real industrial measurement scenarios. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the measurement accuracy and stability of the electromagnetic flowmeter are easily affected by the flow pattern when measuring the gas-liquid two-phase flow, this paper proposes a gas-liquid two-phase flow measurement method using the electromagnetic flowmeter under phase-isolation state. A cyclone was used to shape the irregular two-phase flow inlet flow pattern into a gas core-water ring flow, ensuring the orderly distribution of the weight function. Void fraction was introduced to modify the electromagnetic flowmeter measurement model to improve the measurement accuracy. Using air-water two-phase flow as the medium, the measurement method was verified thro ugh laboratory experiments. The results show that the liquid phase measurement error of the electromagnetic flowmeter is within ±5% under phase-isolation state. The research conclusions of this paper provide a good idea and method for gas-liquid two-phase measurement in industrial production, and have good application value. [ABSTRACT FROM AUTHOR]

To create conditions for the recognition of Kazakhstan certificates of conformity and the results of product tests, an assessment of measurement uncertainty is required. In this regard, there has been observed the activation of the practical application in Kazakhstan of the concept of measurement uncertainty. The authors developed a physical stand for a mobile complex designed to verify electromagnetic flowmeters at the place of operation. To obtain verification results, programs were developed to calculate the measurement uncertainty of an electromagnetic flowmeter using the NI LabView graphical programming environment. In addition, a model for estimating the uncertainty of the relative error of flowmeters was proposed, and the measurement uncertainty was estimated using three methods: standard, Monte Carlo, and Kragten. Finally, a comparative analysis was conducted on the results of the estimation of the uncertainty of the relative error of a flowmeter. All methods give standard uncertainty values that do not exceed the acceptable range of relative error (± 1%). However, Monte Carlo method gives better results for sufficiently large number of simulations. No significant differences between the results obtained using standard and Kragten method were discovered. [ABSTRACT FROM AUTHOR]

Abstract We present a concept of an electromagnetic phase-shift flowmeter that has a significantly reduced sensitivity to the variation of the electrical conductivity of a liquid metal. A simple theoretical model of the flowmeter is considered where the flow is approximated by a solid finite-thickness conducting layer which moves in the presence of an ac magnetic field. In contrast to the original design (Priede et al., 2011), where the flow rate is determined by measuring only the phase shift between the voltages induced in two receiving coils, the improved design measures also the phase shift between the sending and the upstream receiving coils. These two phase shifts are referred to as internal and external ones, respectively. We show that the effect of electrical conductivity on the internal phase shift, which is induced by the flow, can be strongly reduced by rescaling it with the external phase shift, which depends mostly on the conductivity of medium. Two different rescalings are found depending on the ac frequency. At low frequencies, when the shielding effect is weak, the effect of conductivity is strongly reduced by rescaling the internal phase shift with the external one squared. At higher frequencies, the same is achieved by rescaling the internal phase shift directly with the external one. Highlights • A concept of next-generation electromagnetic phase-shift flowmeter is proposed with a significantly reduced sensitivity to the variation of the electrical conductivity of a liquid metal. • The flowmeter is a development of the original design by Priede et al. [19] which is also covered in the Flow Measurement Handbook of Cambridge University Press (2016) by R. Baker, and commercialised by the German company SAAS GmbH (http://www.saas-online.de. [ABSTRACT FROM AUTHOR]

Abstract We present a comprehensive numerical analysis of alternative transient eddy-current flowmetering methods for liquid metals. This type of flowmeter operates by tracking eddy-current markers excited by the magnetic field pulses in the flow of a conducting liquid. Using a simple mathematical model, where the fluid flow is replaced by a translating cylinder, a number possible alternative measurement schemes are considered. The velocity of the medium can be measured by tracking zero crossing points and spatial or temporal extrema of the electromotive force (emf) induced by transient eddy currents in the surrounding space. Zero crossing points and spatial extrema of the emf travel synchronously with the medium whereas temporal extrema experience an initial time delay which depends on the conductivity and velocity of the medium. Performance of transient eddy-current flowmetering depends crucially on the symmetry of system. Eddy current asymmetry of a few per cent makes the detection point drift with a velocity corresponding to a magnetic Reynolds number Rm ∼ 0.1. With this level of asymmetry transient eddy-current flowmetering can be reliably applicable only to flows with Rm ≳ 0.1. A more accurate symmetry adjustment or calibration of flowmeters may be necessary at lower velocities. Highlights • Alternative measurement schemes of the transient eddy-current flowmeters for liquid metals are considered and a comprehensive numerical analysis of their operation is presented. • It is pointed out for the first time that the operation of transient eddy-current flowmeters relies crucially on their symmetry. • Our results may be useful for designing more accurate and reliable transient eddy-current flowmeters for liquid metals. [ABSTRACT FROM AUTHOR]

Highlights • An optimized phase-isolation method for vertical flow is proposed. • The behavior of electromagnetic flowmeter worked in phase-isolation is analyzed. • An automatic image processing algorithm is developed. • Electromagnetic flowmeter and image processing are used based on phase-isolation. Abstract In this paper, the electromagnetic flowmeter and the image processing are used to measure vertical gas-liquid two-phase flow. In order to reduce the effect of randomly distributed bubbles on the weight function of the electromagnetic flowmeter and the bubbles overlap on the image processing in raw two-phase flow, a special implementation method of phase-isolation for vertical upward flow is developed to achieve a stable and uniform swirling core-annular flow. For this flow pattern, the behavior of the electromagnetic flowmeter is analyzed and an automatic image-processing algorithm is developed. Both the simulated gas column experiment and dynamic air-water two-phase flow experiment were carried out to verify the theoretical equation of liquid flowrate. The results demonstrate that the instrument constant of electromagnetic flowmeter does change in the annular flow cross-section. A cross-section shape coefficient k α is needed in the equation of liquid flowrate, and k α is proved to be only related to the void fraction, independent of the type of electromagnetic flowmeter and the properties of central insulated column. Moreover, the swirl has no effect on the electromagnetic flowmeter. The overall average error of the liquid flow rate is 2.6%, and the relative error is within ±5% in bubble and slug flow condition. The measurement result is immune to the gas velocity. [ABSTRACT FROM AUTHOR]

Under the conditions of low flow rate and strong noise, the current electromagnetic flowmeter (EMF) cannot satisfy the requirement for measurement or separate the actual flow signal and interference signal accurately. Correlation detection technology can reduce the bandwidth and suppress noise effectively using the periodic transmission of signal and noise randomness. As for the problem that the current anti-interference technology cannot suppress noise effectively, the noise and interference of the electromagnetic flowmeter were analyzed in this paper, and a design of the electromagnetic flowmeter based on differential correlation detection was proposed. Then, in order to verify the feasibility of the electromagnetic flow measurement system based on differential correlation, an experimental platform for the comparison between standard flow and measured flow was established and a verification experiment was carried out under special conditions and with flow calibration measurements. Finally, the data obtained in the experiment were analyzed. The research result showed that an electromagnetic flowmeter based on differential correlation detection satisfies the need for measurement completely. The lower limit of the flow rate of the electromagnetic flowmeter based on the differential correlation principle could reach 0.084 m/s. Under strong external interferences, the electromagnetic flowmeter based on differential correlation had a fluctuation range in output value of only 10 mV. This shows that the electromagnetic flowmeter based on the differential correlation principle has unique advantages in measurements taken under the conditions of strong noise, slurry flow, and low flow rate.

The purpose of this work is to create an automated system that would improve the efficiency of the process equipment in the accounting of costs. In this work, the object of the study is the process of dependence of the EMF on the change in the magnetic field. Methods of research are methods of empirical level, such as: measurement, comparison; Methods of experimental-theoretical level: analysis and experimental research and methods of theoretical level: studying and generalization.

The electromagnetic flowmeter has presented excellent performance in single-phase flow. However, there are many fundamental difficulties when it is applied in two-phase flow. The presence of the insulating phase at various positions in two-phase flow strongly influences the distribution of the weight function, consequently resulting in the uncertainty and instability of the electromagnetic flowmeter's output. When the insulating phase contact with the electrode, it even leads to wrong alarm. In this paper, at the upstream of the electromagnetic flowmeter a phase-isolation method was used to change the inlet flow pattern into a uniform and symmetrical swirling core-annular flow, in which gas-liquid mixture was isolated to gas core and liquid annular flows flowing concurrently in the transmission pipe with a clear smooth interface between them. Then we analysed the behavior of the electromagnetic flowmeter performed in this specific flow pattern, and built the liquid flow rate measurement model. Besides, the void fraction was measured by image processing technique. Owing to the clear smooth interface, the difficulty of image processing and the measurement error of the void fraction can be reduced. The experimental results showed that, the combination of the phase-isolation method could improve the measurement accuracy and successfully make the electromagnetic flowmeter available for the gas-liquid two-phase flow where the original phase distribution is not uniform. [ABSTRACT FROM AUTHOR]

We investigate the influence of the magnetic Reynolds number Rem on the signal from electrodes in an the electromagnetic flowmeter. Conditions for eliminating this dependence by applying an inhomogeneous magnetic field, several pairs of electrodes, and a numerical integration algorithm are considered. We demonstrate the possibility of calibrating the flowmeter using a low-capacity liquid-metal flow fixture. [ABSTRACT FROM AUTHOR]

Flow measurement is of great importance in many industries, such as the chemical industry, energy and urban drainage. Electromagnetic flowmeter is widely used due to its wide range, high response and suitability for multiphase flow detection. To meet the needs of small-caliber and low-flow applications and wider installation scenarios, this paper proposes a new insertion-type right-angled bent electromagnetic flowmeter. The measurement signal of the electromagnetic flowmeter is closely related to its internal fluid flow state, thus computational fluid dynamics (CFD) method is used to optimize the electrode shape and contraction section shape of the electromagnetic flowmeter. Through comparison experiments of flat electrodes and cone electrodes, a better model is obtained. Furthermore, three new models of the contraction section are proposed: the sharp contraction type, the gradual contraction type, and the Widosinski curve contraction section. The Widosinski curve contraction section is easier to stabilize the flow field inside the flowmeter. The experimental data are in good agreement with the results of the large eddy simulation, and the results show that the measurement performance of the cone electrode is better than that of the flat electrode. When measuring small flow rates, the error of the cone electrode is only 5%, much smaller than the error of the flat electrode. The findings of this study provide a new idea for the development and optimization of the measurement performance of the right-angled electromagnetic flowmeters. [Display omitted] • A novel insertion-type right-angled electromagnetic flowmeter is introduced. • The new flowmeter is particularly suitable for corner installation. • The flowmeter exhibits higher accuracy using cone electrodes instead of flat electrodes. • The Widosinski curve contraction section outperforms two other designs. [ABSTRACT FROM AUTHOR]

• A new optimization method of electromagnetic flowmeter with mesh electrode is proposed and studied. • The virtual current density model of the new mesh electrode is established and derived. • The new mesh electrode was verified and comprehensively evaluated. • The electromagnetic flow measurement system composed of a new mesh electrode has the advantages of small measurement error and strong stability. Electromagnetic flowmeter(EMF) is a common volumetric flow measurement instrument widely used in industrial flow measurement. With the development of EMF in the direction of high precision and intelligence, it is increasingly urgent to further improve the accuracy of EMF measurement. The key to reducing measurement error and eliminating the impact of interference noise is optimizing the electromagnetic flow sensor structure. Aiming at the existing EMF electrode optimization deficiencies, a new mesh structure electrode is firstly proposed in this paper. Then, a theoretical study on the distribution of virtual current density based on this mesh structure electrode is carried out, different structure electrodes are verified and analyzed through COMSOL finite element simulation, and the optimal structure design parameters of the new mesh electrode are obtained. Finally, an experimental platform is built, and a comparative experiment is conducted on the electromagnetic flow measurement system composed of the new mesh structure electrodes. The experimental results show that the maximum relative error of the optimized electromagnetic flow measurement system (OEMFS) is reduced by 0.47% compared with the ordinary EMF in the non-axisymmetric flow test. In the low-flow velocity test, the maximum relative error of the OEMFS is reduced by 7.46% compared with the ordinary EMF. In the strong interference test, the steady-state fluctuation of the amplitude of the OEMFS is reduced by 5.01% compared with the ordinary EMF. The OEMFS has better anti-interference, and the relative error of the system is less affected by the change in flow rate. [ABSTRACT FROM AUTHOR]

Downhole micro-flux control drilling technology can effectively solve drilling accidents, such as kick and loss in narrow density window drilling scenarios. Using a downhole annular flow measurement system to obtain real-time information of downhole annular flow is the core and foundation of downhole micro-flux control drilling technology. The research work of electromagnetic flowmeters in recent years creates a challenge for downhole annular flow measurement. This paper proposes a new method for an annular flow measurement system based on the electromagnetic induction principle. First, the annular flow measuring principle, the weight function, the density of virtual current, and the magnetic field of the annular flow electromagnetic measurement system are described. Second, the basic design of the annular flow electromagnetic measurement system is described. Third, model simulation and dynamic experiments on an annular flow electromagnetic measurement system are carried out. The simulation and experimental results show a linear relationship between the system output and the annular flow rate, and also verify the correctness of annular flow electromagnetic measurement theory. [ABSTRACT FROM PUBLISHER]

This paper proposes a dynamic synchronous capture (DSC) algorithm to calculate the flow rate for an electromagnetic flowmeter. The characteristics of the DSC algorithm can accurately calculate the flow rate signal and efficiently convert an analog signal to upgrade the execution performance of a microcontroller unit (MCU). Furthermore, it can reduce interference from abnormal noise. It is extremely steady and independent of fluctuations in the flow measurement. Moreover, it can calculate the current flow rate signal immediately (m/s). The DSC algorithm can be applied to the current general MCU firmware platform without using DSP (Digital Signal Processing) or a high-speed and high-end MCU platform, and signal amplification by hardware reduces the demand for ADC accuracy, which reduces the cost. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

First, the measuring principle, the weight function, and the magnetic field of the novel downhole inserted electromagnetic flowmeter (EMF) are described. Second, the basic design of the EMF is described. Third, the dynamic experiments of two EMFs in oil-water two-phase flow are carried out. The experimental errors are analyzed in detail. The experimental results show that the maximum absolute value of the full-scale errors is better than 5%, the total flowrate is 5-60 m³/d, and the water-cut is higher than 60%. The maximum absolute value of the full-scale errors is better than 7%, the total flowrate is 2-60 m³/d, and the water-cut is higher than 70%. Finally, onsite experiments in high-water-cut oil-producing wells are conducted, and the possible reasons for the errors in the onsite experiments are analyzed. It is found that the EMF can provide an effective technology for measuring downhole oil-water two-phase flow. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Posts & Telecommunications (Natural Science Edition) is the property of Chongqing University of Posts & Telecommunications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this article, a novel four-electrode electromagnetic flowmeter (EMF) is proposed for flow rate measurement in polymer-injection wells. The ideal response model of the four-electrode EMF is established. In this model, the weight function and intensity of magnetic field are both derived, according to which numerical calculations are conducted. The calculation results show that in the annular area between the flowmeter and oil tubing, the weight function and magnetic field are both symmetrically distributed near the measurement electrodes and magnetic poles, respectively, and are rapidly attenuating along the radius direction. The potential difference is calculated for several kinds of flow velocity profiles in the annular area, and the calculation results show that the output of the four-electrode EMF is sensitive to the distribution of the flow profile. The experimental results obtained by using the multiphase flow loop facility show that when the four-electrode EMF is used in polymer solutions, the instrument constant of the four-electrode EMF differs from that used in tap water and remains unchanged with the concentration of the polymer solutions. The flow patterns of tap water and polymer solutions are various, leading to the change of the instrument constant of the four-electrode EMF. On-site experiments show that the four-electrode EMF is suitable for the polymer-injection wells developed in short durations. For the wells developed in long durations, the four-electrode EMF is limited because of the contamination, distortion, and corrosion of the oil tubing. [ABSTRACT FROM AUTHOR]

Oil-in-water two-phase flows are often encountered in the upstream petroleum industry. The measurement of phase flow rates is of particular importance for managing oil production and water disposal and/or water reinjection. The complexity of oil-in-water flow structures creates a challenge to flow measurement. This paper proposes a new method of two-phase flow metering, which is based on the use of dual-modality system and multidimensional data fusion. The Electrical Resistance Tomography system (ERT) is used in combination with a commercial off-the-shelf Electromagnetic Flow meter (EMF) to measure the volumetric flow rate of each constituent phase. The water flow rate is determined from the EMF with an input of the mean oil-fraction measured by the ERT. The dispersed oil-phase flow rate is determined from the mean oil-fraction and the mean oil velocity measured by the ERT cross-correlation velocity profiling. Experiments were carried out on a vertical upward oil-in-water pipe flow, 50 mm inner-diameter test section, at different total liquid flow rates covering the range of 8–16 m 3 /hr. The oil and water flow rate measurements obtained from the ERT and the EMF are compared to their respective references. The accuracy of these measurements is discussed and the capability of the measurement system is assessed. [ABSTRACT FROM AUTHOR]

In view of problem that measurement result of flow of phosphate concentrate slurry is easy to be influenced by density of phosphate concentrate slurry and solid particles in fluid, the paper proposed a measurement scheme of mass flow of phosphate concentrate slurry. The scheme uses frequency output type electromagnetic flowmeter to measure volume flow of fluid, and uses mass flowmeter and densimeter with small caliber paralleled in measuring pipeline to measure real-time density of the fluid, the both measured signals are made accumulated calculation in flow totalizer, so as to realize accurate measurement for mass flow of phosphate concentrate slurry. The actual application shows that the scheme ensures stability, reliability and accuracy of measured data and can realize custody transfer metering for mass flow of phosphate concentrate slurry with lower cost.