Electromagnetic Meter Research Articles

Using Soil Sensors to Assess Soil Salinity

AbstractThis article is reproduced from Chapter 6 of the new book, Salinity and Sodicity: A Growing Global Challenge to Food Security, Environmental Quality and Soil Resilience, in a slightly modified form. The book is available for purchase from Wiley.com or Amazon.com. The article covers the use of electromagnetic (EM) sensors for measuring apparent electrical conductivity (ECa). In the field, electrical conductivity (EC) can be measured by two primary approaches: physical contact and electromagnetic (EM) induction. With physical contact, a current is injected into the soil, and the detector measures the resulting voltage. An EM meter does not make direct contact but uses a coil to produce an EM field. A sensor then measures the soil‐induced changes to the original EM field. Both types of sensors measure the ECa, which is different from laboratory‐derived EC values. When using ECa sensors, it is important to remember that they are sensitive to many factors, including salinity, soil moisture, bulk density, soil texture, and temperature. The purpose of this article is to provide an overview on the use of EM sensors to provide examples on the use of these sensors in the field. Earn 1.5 CEUs in Soil & Water Management by reading this article and taking the quiz at https://web.sciencesocieties.org/Learning‐Center/Courses.

Measurement of the electric field of mobile telephone base station antennas in Riobamba (Ecuador), to determine the specific absorption rate (SAR) in the human body

Exposure to electromagnetic and radio frequency fields generated by communication technologies such as mobile phones has raised concerns about electromagnetic pollution and its possible health effects. The objective of the study was to measure the electric field coming from cell phone base station antennas and determine through simulation in virtual anatomical models the maximum and average SAR in the whole body and in 10 g in different parts of the human body. The measurements were carried out with a selective non-ionizing electromagnetic radiation meter at 10 sites in the city of Riobamba, Ecuador. The highest maximum and average SAR for whole body was 3.045x10−7 and 3.923 x10−8 W/kg, respectively. While, at 10 g, the maximum SAR reached up to 8.52x10−9 W/kg in arms and the average SAR 2.13x10−9 W/kg in legs. All results are well below the limits established by the ICNIRP, suggesting a low risk of exposure. This work provides valuable information on the levels of exposure to electric fields from mobile telephone base stations and the results collected in this research could serve as a reference for future research, since the sampling method used could be reproduced to study the temporal variation of electric field levels in the city and conduct more comprehensive studies of SAR distribution in the human body.

Assessment of Panorama Photogrammetry as a Tool for Long-Range Deformation Monitoring.

This study investigates panorama photogrammetry (PPh) as a potential method to collect massive 3D information for long-range deformation monitoring. Particularly, this study focuses on areas with measuring restrictions, i.e., inaccessible objects and distances above 0.6 km. Under these particular conditions, geodetic techniques based on Electromagnetic Distance Meters (EDMs) or Total Stations (TSs) can provide coordinates with a precision better than 1 cm, but only for a limited number of discrete points. For mass capture, Terrestrial Laser Scanning (TLS) is normally the preferred solution, but long-range instruments are expensive, and drawbacks such as weak return signals and non-automatic target recognition appear. As an alternative, PPh is investigated in the well-controlled area of La Muela in Cortes de Pallas, where images are automatically captured from geodetic pillars using a GigaPan device, processed, and then rigorously compared to TLS point clouds. The results obtained after integrating both techniques into a high-accuracy geodetic reference frame show that PPh and TLS provide similar precision to within approximately 4 cm in the range of 0.6-1.0 km. Therefore, considering cost-effectiveness and ease of use, the proposed method can be considered a low-cost alternative to TLS for long-range deformation monitoring.

A TEG-Based Non-Intrusive Ultrasonic System for Autonomous Water Flow Rate Measurement

Residential water meters accommodate various methods of power provisioning. Electromagnetic and ultrasonic meters, for example, often rely on a battery-like external power source, whereas mechanical meters harvest energy from water flow through an impeller. Although energy harvesting (EH) minimizes maintenance needs driven by battery depletion/replenishment, placing a physical element into the flow adversely affects water pressure. This intrusive EH/sensing technique is not user-friendly either since the meters with impellers need to be embedded into pipes by skilled personnel. Hence, this paper proposes a non-intrusive sensor system powered by thermoelectric generators (TEGs) for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">plug-and-play</i> water flow rate measurement. This system, equipped with a custom-made energy management unit (EMU), adopts ultrasonic sensors, a task-based computing scheme, and a LoRa module for autonomous sensing and reporting of the flow rate. After summarizing thermoelectricity and delta time-of-flight ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\Delta$</tex-math></inline-formula> ToF)-based ultrasonic sensing theory, we provide the system model and design details with a particular focus on the EMU. Then, we experimentally evaluate the system under varying conditions, demonstrating their impact on average sensing and transmission periods. The results unveil that our proposal can achieve high measurement precision ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm 1.4\%$</tex-math></inline-formula> ), comparable to its intrusive and battery-powered counterparts, and thus has the potential of replacing the residential water meters.

The intensity of the magnetic field on different sex of fetus and accuracy of sex detection using gold ring pendulum

Objective: This research aims to measure the intensity of magnetic field of different sex of fetuses and the accuracy of pendulum method for the sex detection of cow fetuses. Methods: Twenty-six Madura cows with gestational age of more than 4 months were used in this research. This research is composed of three steps : 1). Measuring the intensity of the magnetic field on the fetus using an Electromagnetic Field Meter (EMF) type 827 which is affixed to the right side of the abdomen 2). Observe the pattern of the gold ring pendulum used for sex detection of cow fetus 3). Measure the accuracy of the pendulum ring gold method. The data were analyzed using descriptive analysis. Results: The result of this research showed that the intensity of the magnetic field of a male fetus is 0.04 µT for a head, 0.07 µT for back, 0.05 µT for abdomen and 0.03 µT for tail. Magnetic field of a female fetus is 0.03 µT for head, 0.05 µT for back, 0.035 µT for abdomen and 0.01 µT for tail. The gold ring pendulum is a unidirectional pattern for detection male sex showed the accuracy of 91.67% and a rotating pattern for female fetuses showed accuracy of 85.71%. The average accuracy of detection using the gold ring pendulum is 88.46%. Conclusions: The conclusion of this research is male fetuses have a magnetic field higher than male fetus.

Electromagnetic Frequency Pollution in Malawi: A Case of Electric Field and Magnetic Flux Density Pollution in Southern Africa

In this study, electric field and magnetic flux density pollution levels were measured in southern Africa, a case of Blantyre City in Malawi, between 2020 and 2021. Sixty short-term measurements were performed using Trifield Electro Magnetic Frequency meter model TF2 in 30 different locations. Five high-population-dense sampling points were selected from school campuses, hospitals, industrial areas, markets, residential areas, and within the commercial and business center (CBC) of Blantyre. Electric field and magnetic flux density pollution monitoring was conducted between 10:00-12:00 h and 17:00-19:00 h for short-range analysis. Short-range results show that the maximum measured electric field pollution were 249.24 mV/m and 207.85 mV/m between 10:00-12:00 and 17:00-19:00 respectively, which are below the public limits of 4200.00 mV/m for public exposure. Similarly, maximum short-range results for magnetic flux density were 0.073 G and 0.057 G between 10:00-12:00 and 17:00-19:00 respectively which are below the public limits of 2 G for public exposure. Both measured electric and magnetic flux density were compared with the International Commission on Non-Ionizing Radiation Protection (ICNIRP), World health organization (WHO), and Institute of electrical and electronics engineers (IEEE). It was determined that all measured values for both electric and magnetic flux density were smaller than set limits for non-ionizing radiation for both public and occupation health. More importantly, these background measurements establish a baseline for future changes to be compared against public safety.

Similar simulation test study on the influence of mining on shaft deflection of deep soil based on hydraulic permeability model

Ensuring shaft safety is critical in the process of coal mining. During coal mining in the Guotun coal mine, Shandong Province, China, issues, such as shaft deflection, tank channel and shaft deformation, and tank jamming, which did not appear in the shaft before, brought huge hidden dangers to safety. In this study, a set of three-dimensional analog simulation systems for assessing the influence of mining on shaft deflection was designed by using penetration force simulations of gravity fields. In this system, electromagnetic displacement meter is used to collect surface settlement data, which verifies the feasibility of using hydraulic pillow to simulate formation disturbance caused by coal mining. the strain of the shaft is measured by optical fibers and strain gauges, and the amount that mining influenced the deflection of the shaft is obtained. The results show that there is an approximately positive linear correlation between the horizontal displacement of the shaft caused by mining and the mining thickness of the coal. The horizontal displacement of shaft caused by coal mining is inversely proportional to the moving Angle within a reasonable range. The horizontal displacement of shaft is affected by mining mode, and symmetrical mining can significantly reduce the horizontal displacement of shaft. The horizontal displacement of the shaft at different depths caused by mining decreases with increasing shaft depth, which is the main cause of shaft deflection.

Comparative Analysis of Methods for Calculating the Energy Flux Density used in Assessing the Permissible Level of Environmental Pollution by Electromagnetic Radiation

In this article, the results of measurements and calculations of the power flux density in the frequency range 670 MHz-766 MHz (46th and 57th television channels) of digital broadcasting of the DVBT2 standard were presented. Experimental data on the power flux density were obtained by the selective electromagnetic field meters NARDA SRM-3000 with an isotropic antenna. The radiating system consists of 16 panel antennas (four-storey panel antennas) with a circular radiation pattern in the horizontal plane. Calculations were carried out in the ПК АЭМО (Software package for electromagnetic environment analysis) and MMANA programs. The data obtained were compared with the permissible exposure limit (PEL) of energy flux density (EFD) set by health and safety rules and standards (2.1.8/2.2.4.1383-03), which operate on the territory of Russia.The values obtained are significantly less than the acceptable levels. In the USA, Japan, European countries, Canada, China, and the PEL of energy flux density in the frequency range 300 MHz – 300 GHz are higher than in Russia.

Study of domestic water consumption in intermittent supply of the Riberas de Sacramento sector in Chihuahua, Mexico

Abstract User water demand can be met in intermittent water supply systems, and normally it is met if they have sufficient capacity to store water in their homes to be used in the hours when it is not supplied from the public pipe network. The situation in many intermittent water supply systems is that they have enough water to cover the demand of the users but are supplying it intermittently, and the challenge is to achieve a transfer from intermittent to continuous supply. If the delivery of water is continuous, which supplies drinking water 24/7, it covers not only the basic needs of the user, but all the needs for water they may have. The present study was carried out using smart domestic water meters to obtain consumption information in an intermittently supplied pilot sector. The electromagnetic meters record the water flow through pulses and generate consumption information, which gives us the consumption pattern in volume of water and in the time it is used. During the study, multivariate statistical methods were applied to obtain information from the domestic meters and to identify, as realistically as possible, the consumption of drinking water and the relationship between consumption and specific characteristics of the users and thus anticipate future demand. The results showed a close relationship between consumption and the size of the residence. The most influential factors were the number of bathrooms and the number of occupants. A direct relationship between the pressure and the volume supplied was presumed at the beginning of the study but the opposite was found. Equipment was installed to measure the pressure in the network at the time of establishing the continuous supply of drinking water. The multivariate analysis provides a selection of the most important variables that influence and explain the behavior of the water use and consumption pattern, with the operation determined by the operating agency.

Платформа контроля электромагнитного поля для обеспечения безопасности труда и промышленных объектов

The complex direction of measuring electromagnetic field parameters in Industry 4.0 is the underestimated direction. At the same time, modern technologies are actively testing neural network algorithms and the IoT cluster. Current trends in the development of technology dictate the use of new technologies and materials in the design of sensitive elements of electromagnetic field meters, as well as new intelligent methods for obtaining and processing data in real time. The logical development is the crossing of smart measuring devices and the server part with the required algorithmic modules. The conducted studies and experiment showed an unambiguous possibility of creating an unpacked electromagnetic field sensor. The convergence of the results of modeling real operating conditions in the form of inhomogeneous electromagnetic fields and the results of calculating mathematical block structures confirms the correctness of the models. The purpose of using a platform with structurally improved electromagnetic field sensors is to measure the parameters of the electromagnetic field in real time with the output of targeted quantitative results with a sufficient level of accuracy and predict hazardous situations. The platform is based on the measuring and server parts. Sensors or an assembly of several sensors is the final measurement node capable of functioning without user intervention. The node implements the collection of information about the actual parameters of the electromagnetic field at the object, a lot of nodes form the measuring part of the platform. Processing, storage, and generation of reports (messages) are carried out in the server part of the platform. The connection of the measuring and server parts occurs via wireless Internet communication channels.

ULTRASONIC MEASUREMENT TECHNOLOGY IN AUTOMATED CONTROL OF WATER RESOURCES

Control of water resources is becoming an important strategic issue. That is why authorities set the goal for wa-ter agencies to manage the availability of water and create regulations to its rational use. The main point in water control is measurement. There are three important aspects of measurements of water resources: at water extraction from nature, at the consumption and at custody transfer. Control of water consumption sometimes is based not on measurements, but on preliminary estimation, for example, by pumping.&#x0D; Ultrasonic measurement technology as a key feature of automated control of resources has a potential role in this market. In contrast to mechanical (turbine) meters, ultrasonic meters have a priority because they also give a possibility to realize smart metering. In contrast to electromagnetic meters, which also measure with high accuracy and realize smart functions, ultrasonic meters much more suitable for rough water, wastewater and sewage. Such water resources are usually poorly controlled, which means that no one knows their exact cost.&#x0D; Measurement is mandatory to control cost and for billing. Accuracy is important issue, especially when we say about measurements in large pipe diameters. There is practically no alternative to ultrasonic flow meters. Market of diverse meters concentrated on diameters under 400 mm. For larger diameters, only ultrasonic meters are in use. They have many chords, difficult algorithms for data processing. Thus, they are applicable over a very wide flow range.&#x0D; In this paper, we discover transit-time ultrasonic flow meters to understand features of their measurement theory taking into account all factors affecting their work. This article describes errors inherent in these flowmeters during measurements.&#x0D; As far as accuracy is significantly important in billing, the cost of 1% measurement error in consumption of water resources for small (DN50÷DN150 mm) and large (DN200÷DN1200 mm) pipe diameters has been evaluated and analyzed. The losses from the installation of low-quality metering devices are demonstrated and discussed.

Boundary Influence and Flow Characteristics of Orisa and Ala Rivers in Kwara and Ondo States, Nigeria

In this study, the effects of boundary influence on flow characteristics of Rivers Ala and Orisa were investigated. Soil samples were collected from three points each from both rivers namely Glory Parish Area (GPA), Olusola Oke Area (OOA) and Fiwasaye; Aran-Orin Area (AOA), Rore and Omu-Aran on Rivers Ala and Orisa Respectively. A MGG/KL-DCB Portable Electromagnetic Velocity Meter was used to measure the in-situ readings of discharge and velocity at the various points. The sediments collected from the sampling points were placed in the Flume in the Hydraulic Laboratory of Civil Engineering Department, Landmark University. The Flume was then set with the measured parameter (Discharge) for each sampling point to apply the Flume to determine the Velocity for both Rivers at slopes of 0.008 to 0.056 respectively. The velocities obtained at the different slopes were inserted into Manning’s Coefficient equation to obtain the flow characteristics. The relationship between the velocity and Manning’s Coefficient was determined using the Spearman’s rank correlation coefficient. All analyses were done at P-value less than 0.05 level of significance. The velocity varied between 0.0237± 0.0004 and 0.0587± 0.0004 m/s; 0.0542± 0.0004 and 0.0701± 0.0003m/s and 0.0789± 0.0005 and 0.0172± 0.1323m/s for GPA, OOA and Fiwasaye for Ala River and between 0.0751± 0.0007 and 0.1008± 0.0006m/s; 0.0628± 0.0007 and 0.0839± 0.0004m/s and 0.0421± 0.0005 and 0.1076± 0.0004m/s for AOA, Rore and Omu-Aran for Orisa River. The results of the effects of soil boundary influence showed that the velocity was inversely proportional with the Mannings’ coefficient at all sampling points of both rivers if the geometry of the river channel is kept constant. This indicates that areas with high velocities are prone to flooding. Further studies should be carried out on more sampling points on the rivers to confirm flow characteristics of the rivers.

Clinical observation and research on the use of precise electromagnetic power meter (arm dynamometer) for upper limbs to evaluate the holistic function of cardiopulmonary metabolism

Objective: Subjects used upper limb (arm dynamometer) and lower limb precision electromagnetic power meter (cycle ergometer) to perform symptom-restricted limit cardiopulmonary exercise testing (CPET). Then we analyzed the clinical value of arm ergometer CPET. Methods: The upper limb and lower limb precision electromagnetic power meters were used to complete the CPET in two different days for 6 normal people and 9 chronic patients. We analyzed CPET data, calculated related core indicators, and compared normal subjects and chronic patients to analyze the similarities and differences between upper and lower extremities and their correlations. Results: ①Compared with 9 patients with chronic diseases, there were significant differences in age ((33.2±12.7) vs (53.6±8.5) years) and diagnosis in 6 normal people. ②The Peak HR ((131.0±19.0) vs (153.0±22.0) bpm,P<0.05) of upper limb CPET of 15 subjects were lower than lower limb CPET, but the difference in blood pressure was not statistically significant (P>0.05). The Peak VT ((1.3±0.4) vs (1.8±0.4) L) and Peak VE ((51.4±21.1) vs (67.9±22.1) L/min) of lower limb CPET were significantly higher than that of upper limb (all P<0.05), and there was no significant difference in Peak BF When upper limb CPET was used, EX-time ((6.4±0.6) vs (8.5±1.2) min) was shorter than lower limb CPET; Peak Work Rate((73.2±19.6) vs (158.5±40.3) W/min), Peak VO2 ((1.1±0.4) vs (1.7±0.4) L/min), AT ((0.6±0.2) vs (0.9±0.2) L/min), Peak VO2/HR ((8.6±2.3) vs (10.9±2.6) ml/beat), OUEP (34.7±4.3 vs 39.8±5.3)were lower, and the Lowest VE/VCO2(32.6±3.8 vs 28.7±4.9), VE/VCO2 Slope (33.9±4.3 vs 28.3±6.2)were higher than those of lower limb CPET (all P<0.05). The comparison results of the two subgroups of normal and chronic patients were the same as the holistic comparison results. ③EX-time, Peak HR, Peak BF, Peak VT and Peak VE of upper limb CPET had good correlation with the results of lower limb CPET. Besides, the measured value and percentage of the projected value of Peak Work Rate, the measured value, kilogram weight value of Peak VO2 and AT, and percentage of the projected value of Peak VO2, the measured value of Peak VO2/HR also had good correlation. The measured value of OUEP, the measured value and percentage of the projected value of Lowest VE/VCO2 and VE/VCO2 Slope were also the same, when the other indicators had no significant correlation. Conclusion: As a supplement to lower limb CPET, upper limb CPET is highly feasible and safe for holistic functional status assessment. It provides an important supplement to guide the implementation of the holistic plan of individualized precision exercise, which is worthy of our further exploration.

Enhancing transverse mixing by using triangular vane in the straight channel

The transport of pollutants in the large rivers especially in the lowest downstream reach of a river, in which the velocity and the intensity of flow turbulent become very low, is performed to a great extent by dispersion. Any measure to enhance the level of turbulence in the flow field will increase the mixing of pollutants. The main goal of the present study is to investigate how the transverse mixing is increased by using a triangular vane (TV). TV is a hydraulic structure used for bank protection and habitat restoration and is suitable for fish and other aquatic organisms. Experiments were carried out in a flume of 10m long and 0.8m wide. Two different conditions of with and no vane were tested under four different flow conditions. A salt solution was used as a tracer. An electronic concentration measuring equipment consisted of conductivity probes was used which can measure the concentration at 49 nodes in four cross-sections downstream simultaneously. The three-dimensional velocity components were also measured by using the electromagnetic velocity meter and the characteristics of three-dimensional flow patterns including turbulent kinetic energy (TKE) and the vertical distribution of the transverse velocity were analyzed. The result showed that the TV by deviating the velocity vectors to the transverse direction, by developing the secondary flows and by displacing the position of the rotating cells in different transverse sections, causes the transverse mixing to increase 3.2 times and to reduce the complete mixing length by as much as 76% compare to the case of no vane. The average values of the TKE found to be increased by as much as 3 times. Finally, a new dimensionless parameter has been proposed to correlate dimensionless transverse mixing to the flow parameters.

An experimental study on the secondary flows and bed shear stress at a 90-degree mild bend with and without triangular vanes

River outer bank erosion and associated inner bank sedimentation cause river morphological and environmental changes. Triangular vanes are eco-friendly structures used for protection of river bank from erosion and morphological changes, fish passage improvement, and also fish habitat enhancement. In the present study, the 3D velocity components at a mild 90-degree channel bend were measured via an electromagnetic velocity meter with and without installed triangular vane. These tests were conducted at a Froude number of Fr = 0.214. The analysis of data showed that the triangular vane decreased the bed shear stress near the outer bank at the upstream and downstream sections of the vane for a distance of about 11 times the effective length of the vane. The maximum reduction at the upstream and downstream of the structure was calculated to be 67% and 80%, respectively. The strength of the vane-induced secondary flow was greater than that of the bend-induced secondary flow. At the position of 0.8L in the structure's downstream, the strength of the vane-induced secondary flow was maximum, after which started reducing and reached the strength of the bend-induced secondary flow at the position of 7L in the structure's downstream.

Accuracy of Solid-State Residential Water Meters under Intermittent Flow Conditions.

Accurate water consumption measurement of customers is a crucial component of water utility sustainability. During the last decade, sophisticated measuring technologies without moving components, known as solid-state water meters or static meters, have emerged. Solid-state water meters promise an improved accuracy with more processing and transmission capabilities in comparison with traditional mechanical meters. A compromise needs to be reached between energy consumption and battery life as all these new features are extremely demanding on electric energy. The usual approach adopted by the manufacturer is to reduce the frequency with which static meters take measurements of the circulating flow. This reduction in signal sampling frequency can have a significant effect on the accuracy of the instruments when measuring water consumption events of 30 s or less, these events being common in residential customers. The research presented analyses of the metrological performance of 28 commercially available solid-state water meters from six different manufacturers in the presence of intermittent flows of various durations. The results show that the magnitude and dispersion of the error under intermittent flows is significantly larger in comparison to steady state flow conditions. The ultrasonic meters examined were more influenced by the intermittency than the electromagnetic meters.

Design method for flow tube structure of electromagnetic water meter with shrunk measurement tube based on pressure loss-flow restriction

Due to the low flow rate measurement demand for battery-powered electromagnetic water meter, shrunk measurement tubes (such as circular section transition to square section) are often used to enhance flow velocity and measurement performance at small flow rate. However, this will also result in an increase in sensor pressure loss, even exceeding the pressure loss limit. Therefore, it is necessary to study a flow tube structure design method based on pressure loss-flow restriction, and design a flow tube structure which can not only maximize the induced voltage, but also meet the actual pressure loss requirement. Because there are many unknown variables in the formula of pressure loss mechanism, it cannot be directly used in structural design. Therefore, taking DN100 sensor as an example, based on finite element software, the variation of pressure loss with the length, width and height of rectangular section is obtained by orthogonal test method, and the numerical model of pressure loss is established. According to the requirements of industry and induced voltage enhancement, the optimal rectangular section size is found with the established pressure loss numerical model, and the structure of flow tube transition section is further optimized to reduce pressure loss. Finally, the prototype is made according to the optimized structure. Pressure loss experiment shows that the error between simulated value and measured value is within ±2.68% (±0.4 KPa). It means the pressure loss-flow restriction based design method for flow tube structure of electromagnetic water meter with shrunk measurement tube is effective and reliable.

A Fuzzy-SOM Method for Fraud Detection in Power Distribution Networks with High Penetration of Roof-Top Grid-Connected PV

This study proposes a fuzzy self-organized neural networks (SOM) model for detecting fraud by domestic customers, the major cause of non-technical losses in power distribution networks. Using a bottom-up approach, normal behavior patterns of household loads with and without photovoltaic (PV) sources are determined as normal behavior. Customers suspected of energy theft are distinguished by calculating the anomaly index of each subscriber. The bottom-up method used is validated using measurement data of a real network. The performance of the algorithm in detecting fraud in old electromagnetic meters is evaluated and verified. Types of energy theft methods are introduced in smart meters. The proposed algorithm is tested and evaluated to detect fraud in smart meters also.

Electromagnetic Technique for Hydrocarbon and Sand Transport Monitoring: Proof of Concept

Electromagnetic metering offers significant promise in the measurement of low-conductivity medium like in multiphase flow. Such measurements rely on the measurement of conductivity contrasts formed by two medium of substances, one substance being conductive and the other being non-conductive. In these conditions, it is assumed that the permittivity-induced displacement current is small compared to eddy current induced by conductivity, therefore the displacement current is usually ignored. The present study demonstrates, through solution of the electromagnetic forward problem and pilot tests, that the temporal, spatial and frequency related permittivity and conductivity changes are all captured by the induced electrical voltage measurement. Permittivity reflects in the amplitude and the conductivity reflects both in the amplitude and the phase angle of the voltage. The weight of each parameter to the voltage measurement is studied here. The findings of the study disclose that an electromagnetic metering system may offer advantages in continuously monitoring and measuring hydrocarbon contents and solid concentrations via both the amplitude and phase shift changes.

Velocity and Pressure in Rear-End Collisions Between Two Solitary Waves With and Without an Underlying Current

In this paper, we present some theoretical results and we use modern electronic equipment to investigate experimentally rear-end collisions between two solitary waves. The surface position, water-particle velocity, and water pressure of the solitary waves are studied for surface waves in an irrotational water flow without an underlying current, with a (uniform) underlying current flowing in the same direction as the wave (“following” current), and a current flowing in the direction opposite to that of the wave (“opposing” current). The experiments involve a small leading wave that is overtaken by a large trailing wave, with a “compound” wave created when the waves overlap. The wave height, the water-particle velocity, and the water pressure are measured as functions of time using a wave gauge, an electromagnetic meter, and a pressure transducer, respectively. These measurements show that in all three scenarios the compound-wave amplitude decreases during rear-end collisions and reaches a minimum when the wave crests overlap. The measured water-particle velocity of a single solitary wave is also compared with that predicted by second- and third-order solutions of the governing equations, and the measured vertical distribution of pressure is compared with the theoretical vertical distribution of pressure with and without a current. We also study how the current direction (i.e., following or opposing) affects a solitary wave and present extensive results of water velocity and pressure for rear-end collisions between two solitary waves. For a following current, the wave velocity is greater, but the pressure is less than for a wave with a zero current, while for an opposing current the situation is reversed. This indicates that an underlying current affects the water-particle velocity field and that velocity and pressure are related in rear-end collisions. Thus, the water-particle velocity and pressure in the compound wave are greater than in the small wave and less than in the large wave.