Attenuation of an ultrasonic beam by suspended particles and range of acoustic flow meters in sewer networks

2012 ◽  
Vol 65 (3) ◽  
pp. 478-483 ◽  
Author(s):  
Frédérique Larrarte ◽  
Pierre François
Keyword(s):  
Suspended Particles ◽  
Operating Conditions ◽  
Wastewater Management ◽  
Flow Meter ◽  
Flow Meters ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Ultrasonic Flow Meter ◽  
Intensity Decay ◽  
Sewer Networks

Ultrasonic flow meters are commonly used in wastewater management. Under certain circumstances, a reduction in the flow meter range may occur and cause significant error in the flow rate measurement. Attenuation due to suspended particles is one of the phenomena capable of reducing the flow meter range. The present paper examines attenuation resulting from re-suspended pond sediment over a wide range of concentration values. It appears that a formula established for sand suspensions provides a good estimate of ultrasound attenuation for these types of particles as well. Experiments conducted for wastewater under particle concentrations commonly encountered in sewer networks demonstrate that the attenuation by particles only contributes to a negligible extent towards intensity decay, in accordance with theoretical predictions. We also theoretically determine herein the operating conditions under which the range of an ultrasonic flow meter would be significantly reduced due to particle attenuation.

Investigation of the Use of Ultrasonic Flow Meters at Oil Refining Process Unit

2020 ◽  
pp. 7-11
Author(s):  
E.V. Glebova ◽  
◽  
A.T. Volokhina ◽  
E.A. Polikakhina ◽  
◽  
...  
Keyword(s):  
Flow Rate ◽  
Petroleum Products ◽  
Operating Conditions ◽  
Oil Refining ◽  
Process Unit ◽  
Flow Meter ◽  
Flow Meters ◽  
Pressure Losses ◽  
Oil Refineries ◽  
Ultrasonic Flow Meter

It is known that changes in the flow rate of the medium can directly affect the safety of the process of refining oil and petroleum products. Therefore, the use of high-precision flow meters is one of the safety barriers to prevent possible accidents and incidents. Unfortunately, the task of parametric measurement of the consumption of oil and petroleum products before and after their processing in most cases causes certain difficulties. For this reason, each specific measurement task should be approached from a different perspective, offering different means and methods of measurement, allowing to achieve the most reliable and accurate data on the measured flow rate. Operating conditions at the oil refineries place high demands on flow meters. Conventional orifice flow meters, which are often used to measure flow in the oil refineries, have certain disadvantages: they require frequent maintenance, process interruptions during installation, cause pressure losses in the pipe. Based on the experience of foreign companies in replacing insertion flow meters with clamp-on flow meters, it was decided to use non-invasive (non-contact) flow meters for medium measurement. The advantages of these flow meters are that there is no need to cut pipes, which practically eliminates the risk of leaks occurrence during installation. Also, the ultrasonic flow meter does not have direct contact with the measured medium, which allows avoiding contamination of both the flow meter itself and the medium, as a result, increasing the accuracy and durability of flow measurement at the site. Research objectives: substantiation of the possibility of operation of an ultrasonic flow meter at the oil refining site, recommendations for the use of various sensors, as well as selection of the optimal installation site for the device. The flow rate readings matched the previously established readings taken from the orifice meters. As a result, it is concluded that the ultrasonic flow meters can be used to measure the flow rate of stripped oil.

Flow Calibration and Error Analysis of Dual-Axis Tracking Trough Solar Collector System

2014 ◽  
Vol 654 ◽  
pp. 262-265
Author(s):  
Jian Ling Deng ◽  
Yong Zhu ◽  
Zi Li Zhou ◽  
Rong Rong Zhai ◽  
Ji Feng Song ◽  
...  
Keyword(s):  
Experimental Study ◽  
Mass Flow ◽  
Solar Collector ◽  
Rotation Speed ◽  
Flow Meter ◽  
Flow Measurements ◽  
Flow Meters ◽  
Collector System ◽  
Ultrasonic Flow Meter

In this paper, a dual-axis tracking trough solar collector system is established, and used to measure and calibrate flow rate at different conditions by using the ultrasonic flow meter and mass flow meter, providing important reference for follow-up experimental study. With the changing of the medium’s temperature and the rotation speed variation of the pump, the two flow meters were used to work together to measure the accurate flow measurements, obtaining the measurement error of the mass flow meter. After that, the reason of error and methods used to reduce the error are analyzed.

Elastohydrodynamic Film Thickness in Concentrated Contacts: Part 2: Correlation of Experimental Results with Elastohydrodynamic Theory

1986 ◽  
Vol 200 (3) ◽  
pp. 219-226 ◽  
Author(s):  
R J Chittenden ◽  
D Dowson ◽  
C M Taylor
Keyword(s):  
Film Thickness ◽  
Experimental Studies ◽  
Elastohydrodynamic Lubrication ◽  
Operating Conditions ◽  
Experimental Results ◽  
Experimental Techniques ◽  
Dimensionless Parameters ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Computational Procedures

The existence of a coherent film of lubricant between highly loaded machine elements has been recognized for many years. Over this period of time measurements of film thickness have gone hand in hand with theoretical analyses in the field now known as elastohydrodynamic lubrication. The experimental techniques of capacitance, electrical resistance and X-ray measurement have been supplemented by the use of optical interferometry while the analytical expressions obtained with the use of elegant simplifications have been superseded by those developed from extensive and comprehensive computational procedures. These developments in experimental techniques have yielded a substantial number of measurements of both minimum and central film thickness. Likewise, the advent of the digital computer has allowed the derivation of a large number of solutions to the problem of elastohydrodynamic lubrication of concentrated contacts. All these results, covering a wide range of geometrical conditions, are to be found in the literature, yet little attempt appears to have been made to assemble a representative set of experimental data to permit a detailed evaluation of the theoretical formulae for elliptical contacts. The second part of this paper therefore considers the correlation between a number of experimental studies covering a wide range of operating conditions and geometries, and the predictions of recent elastohydrodynamic theory. Some of the important aspects of each set of experimental results are then considered and examples are provided which illustrate the following points: 1. Good estimates of lubricant film thickness may be obtained from the theoretical expressions recently derived, even when the dimensionless parameters involved are outside the ranges considered in the derivation of the formulae. 2. The discrepancies which exist between theoretical predictions and some of the measured film thicknesses are nevertheless quite large, even when the dimensionless parameters are within their usual limits. On the whole there is good agreement between experiment and theory, while the general trend of the results indicates that theoretical predictions may underestimate the minimum film thickness by about 10 per cent and the central film thickness by about 25 per cent. This measure of agreement is quite remarkable when the extreme difficulty of interpreting the magnitudes of effective and very thin mean film thicknesses between machined components in various forms of experimental equipment is considered.

Evaluation of a Close Coupled Slotted Orifice, Electric Impedance, and Swirl Flow Meters for Multiphase Flow

2013 ◽  
Author(s):  
Gerald Morrison ◽  
Sahand Pirouzpanah ◽  
Muhammet Cevik ◽  
Abhay Patil
Keyword(s):  
Multiphase Flow ◽  
Flow Rate ◽  
Swirl Flow ◽  
Response Curves ◽  
Flow Meter ◽  
Two Phase ◽  
Flow Meters ◽  
Mixture Density ◽  
Wide Range ◽  
Impedance Sensor

The feasibility of a multiphase flow meter utilizing closely coupled slotted orifice and swirl flow meters along with an impedance sensor is investigated. The slotted flow meter has been shown to exhibit well behaved response curves to two phase flow mixtures with the pressure difference monotonically increasing with mixture density and flow rate. It has been determined to have less than 1% uncertainty in determining the flow rate if the density of the fluid is known. Flow visualizations have shown that the slotted orifice is a very good mixing device as well producing a homogenous mixture for several pipe diameters downstream of the plate. This characteristic is utilized to provide a homogeneous mixture at the inlet to the swirl meter. This is possible since the slotted orifice is relatively insensitive to upstream and downstream flow disturbances. The swirl meter has been shown to indicate decreased flow rate as the mixture density increases which is opposite to the slotted orifice making the solution of the two meter outputs to obtain density and flow rate feasible. Additional instrumentation is included. Between the slotted orifice and swirl meter where the flow is homogenous a custom manufactured electrical impedance sensor is installed and monitored. This array of instrumentation will provide three independent measurements which are evaluated to determine which system of equations are robust enough to provide accurate density and flow rate measurement over a wide range of gas volume fractions using a very compact system.

Fluid Motion in Ultrasonic Flowmeter Cavities

1999 ◽  
Vol 121 (2) ◽  
pp. 422-426 ◽  
Author(s):  
Tore Lo̸land ◽  
Lars R. Sætran ◽  
Robert Olsen ◽  
Inge R. Gran ◽  
Reidar Sakariassen
Keyword(s):  
Secondary Flow ◽  
Dynamic Range ◽  
Fluid Motion ◽  
Fluid Flows ◽  
Characteristic Size ◽  
Flow Meter ◽  
Flow Measurements ◽  
Flow Meters ◽  
Ultrasonic Flow Meter ◽  
Cavity Width

The ultrasonic flow meter is a newcomer among flow meters for measuring large quantities of natural gas. It has notable advantages compared to traditional meters. The ultrasonic flow meter is much more compact and has a wider dynamic range for flow measurements than the orifice plate meter. When manufactured, the ultrasonic sensors are often set back from the pipe wall in a cavity. When the fluid flows past the cavities, a secondary flow of vortices with characteristic size equal to the cavity width is established inside the cavities. The aim of this study has been to investigate the influence of this secondary flow on the accuracy of the ultrasonic flow meter. Both measurements and numerical simulations of the cavity flow have been conducted. It has been found from the present work, that the influence of the flow in the cavities on the measurements increases nonlinearly with the pipe flow rate.

Real Time Automatic Calibration of Flow Meters for Real-Time Hydraulic Modelling

2014 ◽  
Author(s):  
Norense Okungbowa ◽  
Noorallah Rostamy
Keyword(s):  
Real Time ◽  
Calibration Method ◽  
Operating Conditions ◽  
Time Averaging ◽  
Flow Ratio ◽  
Flow Meter ◽  
Flow Meters ◽  
Detection Techniques ◽  
Time Calibration ◽  
Dependent Flow

Performance of flow meters is often a function of flow rate as well as properties (density and viscosity) of the fluid measured by the meters. Since comparison of flow meter readings is a key parameter in leak detection techniques, it is desirable that the readings from the flow meters are accurate and comparable. The idea behind real-time calibration of flow meters is to calibrate a flow meter (called the dependent flow meter) against another flow meter (called the independent flow meter) that is assumed to read correctly. The real-time calibration method is useful under two main conditions: i) when the reference flow meter has been calibrated to a high degree of accuracy and the flow readings from the meter are accurate; ii) when the pipeline operating conditions support the fact that the meter-in flow at one station equals the meter-out flow at the other station. By determining the deviation of the dependent flow meter reading from the independent flow meter reading, a time-averaged flow ratio is calculated. However, the flow ratio calculation and time averaging is only updated at prescribed conditions. The proper correction factor is ascertained and then applied to the dependent flow meter reading. The main advantage of using this technique is that the flow meter repeatability is reduced over time below the nominal accuracy of the dependent meter. Note that the term “calibration” in this context does not refer to the standard method of calibrating flow meter with a ‘prover’ but a technique to calculate correction multiplier for flow meter in other to improve the performance of hydraulic models.

Technique on Flow Measurement and Its Application in Low Head and Large Discharge Pump Stations

2007 ◽  
Author(s):  
Yuan Zheng ◽  
Zong-Yin Zhao ◽  
Bo-Qin Fan ◽  
Bo Qu
Keyword(s):  
High Reliability ◽  
Water Transfer ◽  
Flow Meter ◽  
Discharge Measurement ◽  
Wide Range ◽  
North Water ◽  
Ultrasonic Flow Meter ◽  
Low Head ◽  
Pump Stations ◽  
Large Discharge

The accurate discharge measurement of single pump in low head and large discharge pump stations has been considered as a difficult problem for a long time. Recently, with the completion of some pump stations of South-to-North Water Transfer Project in China, many low head and large discharge pump stations completed with gradually contracted inlet conduit need high accuracy of discharge measurement which is necessary to optimize the operation of pump units, sum up the total discharge and get the efficiency of the pump stations. In this literature, problems came across from traditional measurement methods of discharge are given. These methods are including five-hole probe discharge measurement, discharge measurement using current meter and differential pressure transmitter measurement. Among all these methods, the measurement principle, performance, installation and application of 7510P portable ultrasonic flow-meter with multi-path ultrasonic are specially introduced. Generally speaking, the low head pump stations usually have the characteristic of irregular multi-culvert construction with short straight conduit and gradually contracted cross-sections along the flow direction, so the accurate discharge measurement is very difficult to process. By installing multi paths in conduit, adopting technique on installation elevation of international regulations on Gauss integration method which is also employed in calculating flow, the flow can be got. The number of acoustic paths is determined by conduit construction and hydraulic conditions. The arrangements of acoustic paths are placed in the mode cross-link. Then the discharge can be calculated through integrating the obtained velocity in corresponding cross-section. The installation of 7510P portable ultrasonic flow-meter mainly comprises three processes, including the installation of transducers, the arrangement of cables and its connection with flow-meter. Combining the measured discharge in Jiangdu No.2 Pump Station of the South-to-North Water Transfer Project in China, following conclusions are presented: it has well stability, good repeatability of measurement results, high measurement accuracy with the error around ±0.30%, high reliability and the flow-meter fits a wide range of discharge well. The successful application of 7510P ultrasonic flow-meter accumulates useful experience for discharge measurement of single unit of low head and large discharge pump stations and add a new method of accurate field discharge measurement of low head pump stations, meanwhile, it will play a constructive role in the design, construction and management of pump stations.

In-Situ Calibration for Feedwater Flow Measurement

2002 ◽  
Author(s):  
David Peyvan ◽  
Yuri Gurevich ◽  
Charles T. French
Keyword(s):  
Velocity Profile ◽  
Flow Measurement ◽  
Cross Correlation ◽  
Operating Conditions ◽  
Integration Scheme ◽  
Flow Meter ◽  
In Situ Calibration ◽  
Profile Correction ◽  
Ultrasonic Flow Meter

With the approval by the Nuclear Regulatory Commission (NRC), of the Appendix K power uprates, it has become important to provide an accurate measurement of the feedwater flow. Failure to meet documented requirements can now more easily lead to plant operations above their analyzed safety limits. Thus, the objective of flow instrumentation used in Appendix K uprates, becomes one of providing precise measurements of the feedwater mass flow that will not allow the plant to be overpowered, but will still assure that maximum licensed thermal output is achieved. The NRC has licensed two technologies that meet these standards. Both are based on ultrasonic measurements of the flow. The first of these technologies, which is referred to as transit-time, relies on the measurement of differences in time for multiple ultrasonic beams to pass up and downstream in the fluid stream. These measurements are then coupled with a numerical integration scheme to compensate for distortions in the velocity profile due to upstream flow disturbances. This technology is implemented using a spool piece that is inserted into the feedwater pipe. The second technology relies on the measurement of the velocity of eddies within the fluid using a numerical process called cross-correlation. This technology is implemented by attaching the ultrasonic flow meter to the external surface of the pipe. Because of the ease in installation, for atypical situations, distortions in the velocity profile can be accounted for by attaching a second ultrasonic flow meter to the same pipe or multiple meters to a similar piping configuration, where the flow is fully developed. The additional meter readings are then used for the calibration of the initial set-up. Thus, it becomes possible to provide an in-situ calibration under actual operating conditions that requires no extrapolation of laboratory calibrations to compensate for distortions in the velocity profile. This paper will focus on the cross-correlation method of flow measurement, starting with the theoretical bases for the velocity profile correction factor and its reliance on only the Reynolds number to produce an accurate measurement of the flow, when the flow is fully developed. The method of laboratory calibration and the verification of these calibrations under actual plant operating conditions will be discussed. This will be followed by a discussion of how this technology is being used today to support the Appendix K uprates. Various examples will be presented of piping configurations, where in-situ calibrations have or will be used to provide an accurate measurement of the feedwater flow at a specific location.

scholarly journals Numerical Flow Disturbance Testing of the Innovative Ultrasonic Flow Meter

2021 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Fluid Flow ◽  
Velocity Field ◽  
Velocity Profiles ◽  
Ultrasonic Measurement ◽  
Flow Meter ◽  
Flow Disturbance ◽  
Flow Meters ◽  
Technical Requirements ◽  
Ultrasonic Flow Meter ◽  
Measurement Area

Ultrasonic flow meters are devices for fluid flow measurement using the ultrasonic principle. Within the technical requirements for gas meters, the flow disturbance test is required. The aim of this study was the CFD analysis of the fluid flow field inside the ultrasonic gas meter regarding the influence of flow disturbance. The methodology for numerical analysis and results assessment was defined. The velocity profiles in the area for ultrasonic measurement have been obtained. The evaluation of the profiles was aimed to confirm that the velocity field (profile) is flow independent. Furthermore, it was necessary to prove insensitivity to input disturbance. The obtained results lead to the statement that the velocity profiles can be considered invariant when the flow rate changes and the disturbance do not affect the velocity field in the ultrasonic measurement area. The influence of disturbance should be negated due to the flow meter channel used.

Applicability of hybrid ultrasonic flow meter for wide-range flow-rate under distorted velocity profile conditions

2018 ◽  
Vol 94 ◽  
pp. 49-58 ◽  
Author(s):  
Ei Muramatsu ◽  
Hideki Murakawa ◽  
Daiki Hashiguchi ◽  
Katsumi Sugimoto ◽  
Hitoshi Asano ◽  
...  
Keyword(s):  
Velocity Profile ◽  
Flow Rate ◽  
Flow Meter ◽  
Wide Range ◽  
Ultrasonic Flow Meter
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