Measurement Library

International Symposium on Fluid Flow Measurement Publications (1995)

Procedures And Equipment For Field Proving Coriolis Meters
Author(s): Cathy Apple, K. T. Liu
Abstract/Introduction:
As one of the fastest growing flowmeter technologies, Coriolis meters are now gaining wider usage in the petroleum and petrochemical industries for custody transfer measurement. As with other traditional custody transfer flowmeters, periodic on-line proving of the Coriolis meter is required. At present, volumetric provers, such as conventional pipe provers and small volume provers, are regarded as the only practical means for flowmeter proving. Depending on how the Coriolis meters output is configured, proving techniques differ. In general, if a Coriolis meter is configured to provide mass flow output, an accurate fluid density during proving will need to be determined for volume-to-mass conversion calculations. If a Coriolis meter is configured to provide volumetric flow output, then the same proving procedure for conventional volumetric flowmeters can be adopted. This paper describes the procedures and associated equipment needed for field proving of Coriolis meters. Field proving data collected from several meter installations has shown acceptable proving repeatability and meter factor stability.
Go to Download Page
Email Reference
Document ID: 21DD2D9D

Multipoint Optical Volumetric Flowmeter
Author(s): Medhat Azzazy
Abstract/Introduction:
A multipoint optical volumetric flowmeter has been developed and tested in the field. The volumetric flow rate is determined by simultaneously measuring the velocity profile at a number of stations along the pipe diameter without the need for any mechanically moving parts. The velocity is measured using a diode array velocimetry (DAV) technique, and the simultaneous multipoints are generated using a holographic optical element (HOE) lens. The volumetric flow rate is then obtained by integrating the velocity profile over the pipe cross sectional area. Field tests show that volumetric flow rate uncertainties of DAV/HOE are 0.06% when compared to sonic nozzles. The field tests also demonstrate the ability of DAV/HOE to perform under harsh conditions.
Go to Download Page
Email Reference
Document ID: F51EE65F

Use Of Clamp-On Transit-Time Ultrasonic Flowmeters In Compressed Gas Applications
Author(s): J. Baumoel
Abstract/Introduction:
This paper describes the use of the non-intrusive Clamp-On Transit-Time Ultrasonic flowmeter in the measurement of flow rate, Custody Transfer Totalization, Interface Detection, Batch Tracking, Product Type and Quality identification of liquified and compressed hydrocarbon gas. Actual field data is presented for this technology.
Go to Download Page
Email Reference
Document ID: 652B9167

Elevated Pressure Performance Of Diaphragm Meters - An Mrf Program
Author(s): K. A. Behring II
Abstract/Introduction:
Diaphragm meter data were acquired in the Gas Research Institute (GRI) Metering Research Facility (MRF) at elevated pressures to evaluate volume flow rate bias errors (if present), relative to ANSI B109.1 (1) and ANSI B109.2 (2) specifications, that may be induced as a result of the pressure conditions. Simultaneous pressure drop data were acquired in order to verify the ANSI General Service Capacity Equation predictions, which are used to scale meter flow capacity from one operating condition to another.
Go to Download Page
Email Reference
Document ID: FC4D3991

A Measurement Assurance Program Map() Using Sonic Nozzles
Author(s): Richard W. Caron, Charles L. Britton
Abstract/Introduction:
Ford Motor Company is involved in accurately measuring the air flow to internal combustion engines. In this endeavor, Ford has constructed many different flow test stands and, to be assured that each flow test stand is measuring the air mass flow rate correctly, a Measurement Assurance Program (MAP) has been implemented.
Go to Download Page
Email Reference
Document ID: E452D3B6

Optimal Straightening Vanes For Turbine Meters
Author(s): H. H. Dijstelbergen, J. T. m. Bergervoet
Abstract/Introduction:
The sensitivity of turbine flow meters to a set of disturbed velocity profiles can be used to give an indication of the errors that may occur in practical circumstances as a result of installation conditions. The International Standard ISO 9951 defines a set of perturbations that are suitable for this purpose. The Standard requires the manufacturer to specify the installation conditions, such. as straight lengths, straighteners, etc. so that the change in error due to the standard perturbations is less than one third of the maximum error allowed for undisturbed flow.
Go to Download Page
Email Reference
Document ID: 0D6AA709

Intercomparison Exercise Of High Pressure Test Facilities Within Gerg
Author(s): m. Diritti, m. Arietti, m. V. Cannizzo, P. m. A. Van Der Kam, H. Bellinga, F. J. Delhez, F. Deneuve, D. Donat, W. Frankvoort, B. Harbrink, W. Kerkmann, R. Norman, P. Rombouts
Abstract/Introduction:
Under the auspices of GERG, two Transfer Standard Packages were used to check to what extent gas flowrate measurements at high pressures, obtained in seven different European laboratories, are comparable and to reveal possible ways of improving their performance. The majority of the laboratories involved in this intercomparison produced very accurate results. In fact an evaluation of systematic differences, installation effects, short and long term stability showed a general high level of accuracy in their gas flowrate measurements.
Go to Download Page
Email Reference
Document ID: 1E28A0AA

The Q.SONIC Ultrasonic Gas Flowmeter For Custody Transfer
Author(s): Jan G. Drenthen
Abstract/Introduction:
This paper presents an outline of the theory and methods applied in ultrasonic gas flow metering for custody transfer. The development of a multipath instrument for custody transfer will be discussed, and recent developments will be indicated. Practical applications are illustrated using the Servex 5-path Q.Sonic custody transfer flowmeter.
Go to Download Page
Email Reference
Document ID: 186B76EF

Performance Characteristics Of Transit Time Ultrasonic Flow Meters
Author(s): W. R. Freund, K. L. Warner
Abstract/Introduction:
Transit time ultrasonic flowmeters are increasingly being used in the measurement of natural gas flows. Multipath ultrasonic flowmeters are sufficiently accurate for custody transfer metering. The operating characteristics of these meters are explored by means of a model whose performance is linear with average velocity. Calibration of multipath ultrasonic flowmeters using chorda) integration techniques can be accomplished with measurements of the geometry of the meter and delay times for the transducers. The effect of measurement errors in geometry and time on the performance curve of the meter are studied. Test results are given for 300 mm and 150 mm ultrasonic flowmeters.
Go to Download Page
Email Reference
Document ID: 4ED5D8F1

Field Performance Of The Gallagher Flow Conditioner
Author(s): J. E. Gallagher, P.J. Lanasa
Abstract/Introduction:
This paper contains a summary of the current state of the art for flow conditioners, the basis for the Gallagher Flow Conditioner (GFC), and experimental results from several evaluations.
Go to Download Page
Email Reference
Document ID: A683FA8C

Custody Transfer Metering Performance For Turbine And Positive Displacement Meters On Batched Crude Oil Pipelines
Author(s): J. E. Gallagher, J. R. Coats, H. W. Butts, P.J. Lanasa
Abstract/Introduction:
The USA pipeline grid is quickly migrating from transporting low viscosity crude oils to large volumes of moderate to high viscosity crude oils. As a result,the challenges associated with custody transfer, loss control and line integrity have been brought to a new level.
Go to Download Page
Email Reference
Document ID: 5B7C7BE5

Gri-Developed Compact Gas Meter Using Positive Displacement
Author(s): Thomas Green
Abstract/Introduction:
Successful development and sale of any product require the proper identification of customer needs, both from a technological and economic perspective and from the manufacturers ability to deliver upon these needs. This paper chronicles many of the significant events - scientific, philosophical, and unforeseen - that shaped the development of the four-chamber, compact 7.1 mVh (250 cfh) gas meter. GRIs role in this effort began with Compact Gas Meter Workshops in July 1989 and March 1990, with the gas industry perceived loss of market penetration in multifamily housing to the electric industry in the 1980s. Current gas utility needs state that a compact gas meter must be competitively priced, capable of linking to a communications network, and provide for improved installation flexibility at a reduced cost.
Go to Download Page
Email Reference
Document ID: F80EA03F

New Technology Directly Measures Mass Flow Of Gas
Author(s): David T. Hahn
Abstract/Introduction:
According to recent industry surveys and solicitations by organizations such as the Gas Research Institute and Small Business Innovation Research, a need exists for a gas flowmeter with 0.5% or better accuracy, that does not need to be calibrated for specific gas properties, and requires no periodic maintenance. Over the past 18 years, Coriolis mass flowmeters have provided these features for liquid flow applications, and have won a significant share of the liquid flow measurement market. Coriolis meters continue to be the fastest growing technology in the world market for flow measurement. Coriolis mass flowmeters have not, however, had much success in penetrating the gas flow measurement market due to some limitations involved with measuring the low density fluids associated with low pressure gas flow measurement. A new type of Coriolis mass flowmeter has been developed which utilizes a unique new method of creating and measuring the requisite Coriolis forces. This new technology radial mode Coriolis mass flow measurement, has several inherent features that make it perfectly suited to measuring the mass flow of gas.
Go to Download Page
Email Reference
Document ID: 5FFF5D94

Mexican Primary Standard For Liquid Flow Measurements. Needs, Priorities And Benefits
Author(s): L. Hernandez, H. Luchsinger, R. Arias, S. Trujillo, m. Maldonado, A. Loza
Abstract/Introduction:
The liquid flow facility at the Centro Nacional de Metrologia (CENAM), now under construction, will constitute Mexicos primary standard for liquid flow measurements. The system will have flowrate capabilities from 0,0028 m/s to 0,1936 m/s (first phase) and pressure range up to 1 MPa. It is planned that flowrate could be measured with a total uncertainty of 0,13%. It is designed according to international standards and with recommendations suggested mainly by NIST USA, PTB Germany, and NEL in Scotland, based on a static weighing principle with capacity of 10 000 kg. Frequency converters coupled to the pumps allow an effective flow-rate control and minimize energy waste in the by-pass line.
Go to Download Page
Email Reference
Document ID: F9322F0B

Large Scale Flow Calibration By Capacitance Measurement Within A Tank
Author(s): J. Holste, S. Pipkins, Q. Ran, K. Hall, G. Morrison
Abstract/Introduction:
The focus of this paper is to introduce a novel method for calibrating natural gas flow meters. This new method can accommodate very large flow rates and it avoids common problems associated with current techniques for meter proving. In this method, the amount of gas accumulated in a vessel of fixed volume is determined by measuring the change in capacitance of the vessel with respect to time. Because the accumulator has a fixed volume the problems inherent with the mechanical motions involved in volumetric provers such as bell provers, piston provers and ball provers are eliminated. Accurate measurements can also be made in larger vessels than would be feasible for gravimetric provers, especially for in situ calibrations. Along with avoiding the fundamental problems associated with current provers, initial studies indicate that accuracies of 0.1% are possible, even for flow rates in large pipelines.
Go to Download Page
Email Reference
Document ID: 59EEA39E

Installation Effects On The V-Cone Flowmeter
Author(s): Stephen A. Ifft
Abstract/Introduction:
Installation requirements are of major importance in the overall cost of installing and operating flowmeters. In an effort to quantify the installation requirements of the V-Cone flowmeter in compressible gases, the McCrometer Division of Kelcnia contracted with Southwest Research Institute (SwRI) in San Antonio, Texas to evaluate the performance of a V-Cone flowmeter (1). McCrometer manufactured a 100 mm V-Cone with a beta ratio of 0.67 for the testing. A baseline test estabhshed the performance of the meter under normal, well-developed flow conditions. Six additional series of tests evaluated the performance of the V-Cone downstream of various installation configurations, such as a single elbow and a plug valve. The results of the tests indicate that the V-Cone can be placed downstream of non-ideal flow conditions and measure flow accurately without the need of a flow conditioner upstream.
Go to Download Page
Email Reference
Document ID: 6B8CD720

Advances In Pipe Prover Technology
Author(s): Peter P. Jakubenas
Abstract/Introduction:
The petroleum industry has used pipe provers for on line calibration of liquid flow meters for over 30 years. Recently a number of innovations have come to the forefront that enhance the reliability of pipe provers, reduce their size, make them more accurate, and increase their value to the end users. With the widespread use of turbine meters for custody transfer, accurate measurement is more dependent on frequent proving, thus the industry will continue to demand advanced provers and proving techniques. The author will discuss the aforementioned subject with regard to both bidirectional and unidirectional pipe provers.
Go to Download Page
Email Reference
Document ID: 740AED65

Three-Component Flow Visualization By Dual Mode Tomography
Author(s): G. A. Johansen, T. Fr0ystein, B. T. Hjertaker, 0. Olsen, E. A. Hammer, 0. Isaksen, A.Valle
Abstract/Introduction:
A dual mode tomograph for three-component flow imaging has been built in a cooperative project between the University of Bergen, Christian Michelsen Research AS and Norsk Hydro AS. It is based on an eight-electrode capacitance tomograph and a gamma-ray tomograph with five radiation sources and 85 compact detectors. Embedded Transputers using memory-mapping ensure high speed data acquisition. An Alpha AXP system will be used as an on-line reconstruction unit. The tomographs have so far been tested and characterized as separate systems only. The first test results, however, demonstrate that it is feasible to do three-component flow regime identification at rates above 10 frames/s.
Go to Download Page
Email Reference
Document ID: 54BDD3EB

Effect Of Expanders On Orifice Meter Accuracy
Author(s): U. Karnik, I. Williamson
Abstract/Introduction:
The effect of expanders on orifice meter accuracy has been studied for a 19D meter run. The 62.7mm (2.5in.) to 102.26mm (4.0in.) expander was placed downstream of two elbows in plane. Measurements of velocity profiles and meter comparison tests were taken with and without a tube bundle flow conditioner. Velocity measurements indicate that an expander modifies the velocity field from two elbows in plane. The resulting velocity field appears to be dominated by a single vortex rather than two counter rotating vortices normally seen downstream of two elbows in plane. Results from the meter comparison tests show that two cross over points exist within the 19D meter run. This is in contrast to the single cross over that has been seen thus far for other installations tested in a similar length of meter run. Three types of tube bundles, satisfying AGA standards, were used in the present measurements. The performance of the tube bundle was found to be dependent on the dimensions of the tubes used to manufacture the tube bundle.
Go to Download Page
Email Reference
Document ID: 53CBE2EC

A Compact Orifice METER/FLOW Conditioner Package
Author(s): U. Karnik
Abstract/Introduction:
Flow conditioners have been the center of attention within the natural gas industry for several years. Their importance stems from the fact that, in the presence of existing installations such as elbows, accurate orifice metering can be obtained, within a specified meter length, only if the flow non-uniformities are eliminated. The tube bundle has, thus far, proven to be ineffective in terms of repeatability and reliability. Thus, NOVA embarked on the mission to find a flow conditioner which would, within the shortest possible meter length, provide accurate and repeatable metering. Of the several flow conditioners discussed in the literature, the approach adopted by Laws(1X2), based on screen theory, is best suited to achieve the desired results. However, the Laws flow conditioner has some functional flaws, for example, the claim of a fully developed flow with no account for the effect of Reynolds number. Hence, NOVA has re-designed and modified the existing Laws flow conditioner using screen theory.
Go to Download Page
Email Reference
Document ID: E3F90D8E

Uncertainty Analysis Of A Volumetric Primary Standard For Compressible Flow Measurement
Author(s): Thomas Kegel
Abstract/Introduction:
Primary flow calibration systems are based on measurements of mass and time that yield mass flowrate. One type of system for primary calibration using a compressible fluid involves determination of the mass from values of fluid density and storage tank volume. This paper presents a complete uncertainty analysis of such a system.
Go to Download Page
Email Reference
Document ID: 0390D533

Self-Acting Velocity Profile Device For Natural Gas Under Pressure
Author(s): D. King
Abstract/Introduction:
Accuracy of flowmeters is strongly linked to installation conditions. These installation conditions disturb the flow entering the meters, and hence influence their answers. To know the flow characteristics there is a need to measure the velocity profile. Therefore GDF developped a special device, quick, self-acting, operating in natural gas under pressure from some millibar up to 50 bar. These developpments and profiles measurements have been performed on the GDF natural gas flow metering facilities. Since GDF had this device, GDF had led many studies on installation conditions to improve the knowledge of meter behaviour under disturbed flows. In this paper the general principles of this device are presented and examples of flow profiles given.
Go to Download Page
Email Reference
Document ID: 593F252C

Flow Conditioning For Orifice Plate Flow Meters
Author(s): E. m. Laws, A. K. Ouazzane
Abstract/Introduction:
If acceptable upstream flow conditions for different classes of flow meter are to be produced within short installation lengths a flow conditioner must be viewed as an essential component of any metering installation. Such devices can be classified in terms of their mode of operation into two distinct types, turbulent mixing or vortex action devices. It is demonstrated that a low loss, device combining features of both types of unit can be produced capable of yielding downstream flow conditions close to fully developed, in terms of both time mean flow and turbulence intensity structure, within an overall length of approximately 6 pipe diameters.
Go to Download Page
Email Reference
Document ID: 5F7224E1

Practical Approaches To Multiphase Metering
Author(s): R. Maurer, C. Eng
Abstract/Introduction:
This paper describes some of the practical issues involved in the understanding and specifying of multiphase metering systems. No attempt is made to discuss the merits of various propriety component ratio meters.
Go to Download Page
Email Reference
Document ID: ECAFD739

Recent Advances In Meter Proving Technology
Author(s): R. Maurer
Abstract/Introduction:
This paper will address some of the problems that can arise when a Meter Prover generally of the Small Volume Piston (SVP) or Compact type is manufactured in the USA and has to be re-verified in the UK for a fiscal related application.
Go to Download Page
Email Reference
Document ID: AD07C051

Detection Of Pulsation Effects On Turbine Meters By Pulse Period Modulation Measurements
Author(s): Robert J. Mckee
Abstract/Introduction:
The objective of the research described in this paper is to evaluate the pulse period modulation method as a potential approach for meeting the gas industries needs for detection of pulsation effects on turbine meters at field installations. Research has been conducted as part of the Gas Research Institute Metering Research Program in response to knowledge that pulsation causes over registration of flow in some cases while not causing any errors in other apparently similar pulsating conditions. Operators need to be able to detect when pulsation is causing significant errors.
Go to Download Page
Email Reference
Document ID: 3F01F210

Beta Ratio, Axkymmetric Flow Distortion, And Swdxl Effects Upon Orifice Flow Meters
Author(s): G. L. Morrison, J. Hauglie, R. E. Deotte
Abstract/Introduction:
The objective of this study is to measure the response of the orifice meter to known upstream flow field disturbances generated by a concentric tube flow conditioner and a vane-type swirl generator. These disturbances are characterized by measuring the axial and tangential velocity profiles at the upstream flange tap with no orifice plate present. Two different flow rates are examined which correspond to Reynolds numbers of 91,100 and 120,000 in a 50.8 mm diameter pipe. Eight orifice plates with p4 ratios of 0.43, 0.45, 0.484, 0.55, 0.6, 0.65, 0.7 and 0.726 are studied at both flow rates.
Go to Download Page
Email Reference
Document ID: 93A082B6

Orifice Meter Installation Effects In The Gri Mrf
Author(s): T. B. Morrow
Abstract/Introduction:
Experimental results from the Gas Research Institute (GRI) Metering Research Facility (MRF) are presented on the performance of flow conditioners used to minimize velocity profile distortion and swirl that can cause flow rate measurement errors in orifice meter installations. Orifice meter installation effects tests were performed with several different straightening vane and perforated plate flow conditioner designs in the MRF Interim Low Pressure Loop (ILPL).
Go to Download Page
Email Reference
Document ID: 4B8408E1

Installation Effects On Performance Of Ultrasonic Cross Correlation Flowmeters
Author(s): J. S. Paik, C. H. Kim, D. K. Lee
Abstract/Introduction:
A cross correlation flowmeter having DSP correlator has been developed at KRISS. Since the new correlator has a relatively high s/n ratio, this flowmeter can be used by applying wet method as well as clamp-on method. Before testing the installation effects, baseline of the flowmeter was determined by evaluating the performance under the reference flow conditions which may be described as fully developed. Distortion of the velocity profile was produced by passing the reference flow into the single elbow, double elbows out-of-plane, double elbows in-plane, or a partially open gate valve. Up to 7 % of deviation from the baseline data has been observed depending upon disturbance sources or installation location of ultrasonic transducers.
Go to Download Page
Email Reference
Document ID: 3DB2574E

Uncertainty Estimates For The Gravimetric Primary Flow Standards Of The Mrf
Author(s): Joel T. Park, Kendricks A. Behring II, Terrence A. Grimley
Abstract/Introduction:
Two gravimetric flow standards for mass flowrate are in operation for the calibration of high capacity flowmeters with natural gas. Both systems measure mass electronically from scales which operate on a gyroscopic principle. The gravimetric provers are an integral part of the Gas Research Institute (GRI) Metering Research Facility (MRF) and can provide a direct primary calibration for any conventional gas flowmeter. The smaller system is attached to the Low Pressure Loop (LPL) with an operating pressure of 0.14 to 1.4 MPa (20 to 200 psia) and a flowrate up to 4.6 kg/s (10 lbm/s). The larger system is connected to the High Pressure Loop (HPL) with pressures of 1.4 to 10 MPa (200 to 1,455 psia) and flows to 43 kg/s (95 lbm/s). The performance of these two standards and their estimated uncertainties are described. The optimal total uncertainty in mass flowrate is 0.01 % and 0.02 %, respectively, for die LPL and HPL. The actual uncertainty is dependent on the operating conditions and is primarily a function of the operating pressure and flowrate. Uncertainty estimates are provided on the calibration of turbine meters and sonic nozzles. The largest uncertainty in the calibration of flowmeters is the uncertainty in theoretical models for density and the measurement of natural gas composition.
Go to Download Page
Email Reference
Document ID: 36C6459B

Reynolds Number And Installation Effects On Turbine Meters
Author(s): Joel T. Park
Abstract/Introduction:
Experimental results are presented for four 100-mm (4-inch) turbine meters from three manufacturers and four models. Tests were performed with nitrogen gas in the Low Pressure Loop of the Gas Research Institute (GRI) Metering Research Facility (MRF). The turbine meters were calibrated gas by binary weighted sonic nozzles which were calibrated against a primary gravimetric standard. Reynolds number effects were determined from operating pressures of 0.206 and 0.793 MPa (30 and 115 psia) and flowrates of 34 to 510 m3/h (1,200 to 18,000 acfh). The range for the same Reynolds number at the two pressures was 62,000 to 251,000. The difference in meter factor for the 100-mm (4-inch) meters for two pressures at the same Reynolds number was within 0.4 %. The 100-mm meters were also tested in the A.G.A. Report 7 short-coupled installation. The largest difference from the baseline calibration was -0.3 %. The small difference appears to be a velocity profile effect of two closely coupled elbows in the same plane with the entering and exiting flow in the same direction.
Go to Download Page
Email Reference
Document ID: CE5660B4

Use Of Coriolis Meters In Gas Applications
Author(s): T. Patten, G. Pawlas
Abstract/Introduction:
Coriolis mass flowmeters provide a solution for measuring the mass flow rate of gases directly. Recent calibration data on compressed air shows that the factory water calibration is also valid on air. In addition, a Coriolis meter is fundamentally linear resulting in an accurate measurement over a wide flow range.
Go to Download Page
Email Reference
Document ID: 53E95E06

The Use Of Flow Conditioners To Improve Flow Measurement Accuracy Downstream Of Headers
Author(s): m. J. Reader-Harris, J. A. Sattary, E. Woodhead
Abstract/Introduction:
With the support of the Header Research Consortium the flow profiles and shifts in orifice-plate discharge coefficients have been measured downstream of headers in short meter tubes which include flow conditioners. The effectiveness of recent designs of perforated plate as flow conditioners has been shown, in that they will make shorter installations possible. In addition, CFD computations have been performed to help interpret the experimental data.
Go to Download Page
Email Reference
Document ID: 0B0D5E37

Natural Gas Vehicle Fueling Station Dispenser Meter Evaluations
Author(s): P. F. Rowley, K. Kriha, C. F. Blazek
Abstract/Introduction:
The Institute of Gas Technology (IGT) has constructed a multi-purpose meter evaluation facility capable of testing metering technologies for high flow rate and high pressure NGV dispenser applications. The objective of IGTs meter evaluation program, sponsored by IGTs Sustaining Membership Program and the Gas Research Institute, is to assist the industry in evaluating the performance and accuracy of currently available flowmeters that are being used or could be applied to CNG gas dispensing. These meters are tested at various flow rates and pressures to determine their performance under NGV fueling station operating conditions and to identify the performance characteristics and limitations for each meter. The metering technologies which are being evaluated under this program include Coriolis meter, sonic nozzle meter, and turbine meter designs.
Go to Download Page
Email Reference
Document ID: B53FD00D

The Orifice Expansion Correction For A 50 mm Line Size At Various Diameter Ratios
Author(s): Walt Seidl
Abstract/Introduction:
The expansion coefficient or factor for a compressible flowmeter corrects for the change in pressure and density as the fluid is accelerated through the flowmeter. The expansion correction currently in use in the United States and also in other countries was developed over fifty years ago by Buckingham(1) and Bean.(2) More recent work reported by Kinghorn(3) shows the equation currently in use to be in error.
Go to Download Page
Email Reference
Document ID: 3C6E9389

A Primary High-Pressure Air Flow Measurement Standard In Taiwan
Author(s): Jiunn-Haur Shaw, Fong-Ruey Yang, Yao-Fu Chen
Abstract/Introduction:
A high-pressure air-flow national measurement standard is constructed in Taiwan with a capacity of 8400 Nm3/h and a projected measurement uncertainty of 0.2% in the pressure range of 1 84 bars. It is a blow-down type facility and its main purpose is to serve as the primary standard of a larger-flowrate natural gas flow measurement facility to be built in the future by Chinese Petroleum Company (CPC). The system has a gyroscopic weighing platform suitable for high precision gravimetric measurements and several sonic nozzles with different throat diameters situated in a chamber to be the reference flow meters. A set of two turbine meters, 50mm and 100mm, are used as the transfer standard.
Go to Download Page
Email Reference
Document ID: 942B93B4

The Challenge Of Realistic Testing Of Multiphase Flowmeters
Author(s): V. Sten-Halvorsen
Abstract/Introduction:
Multiphase flowmeters is new technology for the oil industry, and needs to be tested under realistic condiditons to prove their performance. The complex nature of multiphase flow, means that test conditions in a laboratory may not necessary represent the real flow conditions at a field installation. As a concequence, severe field testing is also required to gain experience with the meters and qualify them for field applications.
Go to Download Page
Email Reference
Document ID: 1AA46195

High Speed Nozzle Flowmeter Using Miniaturized Laser-Doppler Techniques
Author(s): V. Strunck, E. A. Krey, H. Miiller, D. Dopheide
Abstract/Introduction:
The application of modern optical techniques to meter calibration and real time measurement of large flowrates is outlined. The basic system consists of a converging device (nozzle) and a miniaturized laser Doppler system integrated inside the wall of a short duct section. Optical access to the flow by means of glass windows is not required anymore. This piugicss has been made possible by a new technique using two separated semiconductor lasers and signal demodulation.
Go to Download Page
Email Reference
Document ID: 8F64FEDE

Investigation Of The Influence Of A Pressure Reducer Placed Upstream Of A Turbine Meter
Author(s): A. Strzelecki, P. Gajan, L. Malard, D. Donat, m. Bosch
Abstract/Introduction:
A pressure reducer is a commonly used device for regulating gas flow in pipelines. This device provides a mechanical constriction in the pipe which reduced the cross sectional flow area and induces a local pressure drop in the flow. A pressure reducer can generate a strong disturbed flow and may induce significant metering errors on flowmeters placed dowstream. This paper presents metering errors obtained with a turbine meter placed downstream of a pressure reducer. The influence of the flow rate, the expansion ratio, the size of the internal valve and the distance between the pressure reducer and the turbine is examined.
Go to Download Page
Email Reference
Document ID: 07EFE2F3

Installation Effects On Multi-Path Ultrasonic Flow Meters: The Ultraflow Project
Author(s): K. Van Dloemcndaal, P. m. A. Van Der Kam
Abstract/Introduction:
ULTRAFLOW was a Joint Industry Project aimed at establishing the effect of installation conditions on multi-path ultrasonic flow meters. An extensive test series was performed at 5 test facilities on 6 and 12 meters operating on natural gas at pressures from 10 to 60 bar. All test facilities and procedures are reviewed by an independent international Quality Assessment Team, comprising experts from legal metrological authorities, to ensure that the work was appropriate to support International Standards activity.
Go to Download Page
Email Reference
Document ID: B1358D65

The Effects Of Dirt And Swtrling Flow On MULTD7ATH Ultrasonic Gas Flow Meters
Author(s): P. m. A. Van Der Kam, S. De Jong, A. m. Dam
Abstract/Introduction:
Gasunie has performed tests on two types of installation effects on multipath ultrasonic gas meters with a diameter of 500 mm. The effect of mildly wet flows was studied by injecting liquids in the gas flow and monitoring changes in signal and noise levels and in the meter error. It was concluded that small amounts of liquids do not affect the meter error, and that the meter itself can detect if signal to noise ratios are distorted so much that proper functioning is no longer possible.
Go to Download Page
Email Reference
Document ID: 1C4FC56F

Studies Related To Gas Metering Accuracy In Natural Gas Vehicle Filling Stations
Author(s): George Vradis, Volkan Otugen, Florin Girlea
Abstract/Introduction:
The present study concentrates on the identification of parameters affecting the metering accuracy in Natural Gas Vehicle (NOV) fueling stations. The results of an on-site monitoring program designed to establish the effect of vibrations and pressure pulsations on the operation of mass flow and rotary positive displacement meters are presented. It is established that pressure fluctuations due to mean flow pulsations are weak in the immediate vicinity of the meters and, based on available experimental results, are not expected to have any impact on meter accuracy. However, vibrations in the operating environment of coriolis mass flow meters are shown to have potentially strong influence on their accuracy. Also, an analysis of available experimental data is performed to identify the source of instabilities observed in the output signal of coriolis mass flow meters. It is shown that such instabilities could be the result of hydrodynamic phenomena that need to be studied further.
Go to Download Page
Email Reference
Document ID: 9706FE67

2-PHASE QUALITY/FLOW Meter
Author(s): Rudy J. Werlink
Abstract/Introduction:
The Quality-flow meter is based on measurement of the dielectric constant variation between die phases of a 2 phase mixture. As the ratio of the two phases changes the overall capacitance changes. Monitoring capacitance changes to measure a physical phenomenon is not a new concept. Indeed, a range of sensors have been developed which utilize capacitance measurements. The present system is not significantly mure sensitive than those available off-the-shelf, but demonstrates a significantly higher dynamic range and quick response than those of which this author is aware. Two prototype sensor designs have been fabricated. The First is a compact quality meter with real time display and remote data capabilities (Quality Meter I). The circuit is optimized for high sensitivity, and 1 second response. The second Prototype is a quality/ flow meter (Quality Meter II)- really two sensors in series for establishing the flow rate and the quality of two phase mixtures. If s circuit is optimized for fast response. Initial testing of the sensors has been successful.
Go to Download Page
Email Reference
Document ID: 3B2D4B3C

The Nova Meter Prover
Author(s): I.D. Williamson, B.D. Sawchuk, U. Karnik
Abstract/Introduction:
The NOVA natural gas meter prover consists of 24 identical sonic nozzles, one of which is diverted to a weigh tank to determine the mass flow rate for that nozzle. The total flow is the measured mass flow multiplied by the number of nozzles in operation. The on-line calibration of a single nozzle avoids the use of the critical flow factor, C*, thereby improving system uncertainty. Uncertainty calculations are presented which show that the uncertainty in the total mass flow rate is between 0.13% and 0.16%, depending on the number of nozzles in operation. Uncertainty of the nozzle bank alone is virtually independent of the number of nozzles open and is between 0.44% and 0.25% depending on how the uncertainty for C* is treated. Use of correlated variables to reduce the uncertainty is addressed. One nozzle from the meter prover was calibrated in air by CEESI. This C* was on average only 0.01% higher than the C* from the NOVA meter prover, with a standard deviation of 0 06% These results also indicate that C may be more accurate than previously thought, however more work is required in this area.
Go to Download Page
Email Reference
Document ID: 80269A4D


Copyright © 2024