Simulation Of A Sonic Nozzle By A Numerical Code
Author(s): Pier Giorgio Spazzini, Orazio Caramia
Abstract/Introduction:
The present work deals describes the numerical simulation of a sonic nozzle performed by a commercial numerical code. The main objective of the work was to assess the reliability of such codes as tools for metrological work. The paper briefly describes the background of numerical simulation of fluid flows, and recalls the main formulations of common use in sonic nozzle analysis. The results show that, for a test case with a well-defined geometry and relatively simple boundary conditions, commercial CFD codes can be a useful support tool for metrological analysis.
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F58DB362
Performance Test Of Mems-Fabricated Critical Flow Venturi Nozzles
Author(s): Chih-Chung Hu, Win-Ti Lin, Cheng-Tsair Yang, Wen-Jay Liu
Abstract/Introduction:
Four types of silicon sonic nozzles for the throat dimension around 90um are investigated at Reynolds number ranging from 6x10 to 8xl03. With a specially designed clamping holder, the silicon nozzle is able to operate at an upstream pressure of 13.8xl05Pa and the above. The critical pressure ratio for choking is insensitive to Re, for which the averaged value is about 0.36. The time length required for the silicon nozzle to reach thermal equilibrium with sonic flow is about 10 minutes. The maximum deviation of discharge coefficients obtained at five different individual days in two months is less than 0.02%, signifying a good long-term stability.
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F1C6E803
Step-Down Procedure Of Sonic Nozzles Calibration
Author(s): Jae Myoung Limf, Bok Hyun Yunf, Hae Man Choi, Kyung Am Park
Abstract/Introduction:
The aim of this paper is to develop the step-down technology of sonic nozzle calibration in very small gas flow rate required in the fields of semiconductor process and NT(Nano Technology). To reach the aim mentioned above the following measuring method was developed. Firstly, several sonic nozzles of the same throat diameters with the same configuration were manufactured and calibrated by means of the standard measurement system. Then a group of sonic nozzles with the similar characteristics was selected. Lastly one of those sonic nozzles is installed upstream, and two or N of the others downstream. In this way characteristics of downstream sonic nozzles were obtained at the low flow rate.
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0885E8DE
The Numerical Simulation On Nozzles
Author(s): Chunhui Li, Chi Wang
Abstract/Introduction:
The laminar, SA and standard ks turbulence models were chosen to numerically simulate the flow field of nozzle in this paper. The comparisons of simulation results showed that SA model could predict the flow field more accurately relative to other models. Appling SA model, we analyzed the change of discharge coefficient for nozzles from small to large size. It was found that the boundary layer took more influence on small nozzles than that on large nozzles, which resulted in the increase of discharge coefficients with increasing throat diameter of nozzles.
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Document ID:
3010CB55
Fault Detection On Turbine Flow Meters Using Time-Frequency Analysis
Author(s): Osmel Reyes Vaillant, Jesus Cabrera Gomez
Abstract/Introduction:
Rotor ball-bearing faults manifestation on turbine flow meters does not appear clearly either in time or spectral domain representation of its output signal. Scalograms obtained from turbine flow meter output signal on faulty conditions, using continuous wavelet transform (CWT) revealed visual differences from the ones obtained in good conditions. Singularity analysis of the correlations coefficient matrix C(b,a) for different segments of these vectors, based upon Lipschitz exponent calculation (Holder continuity criterion), showed local singular behavior associated to high speed transients caused by ball-bearing faults. Results from employing time-frequency signal analysis methods to detect this fault are presented in.this article.
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Document ID:
8E7AB731
Measurement Errors Caused By Asymmetry In Electromagnetic Flow Meter
Author(s): Xiao-Zhang Zhang
Abstract/Introduction:
Numerical models are built to describe the asymmetrical problems in an electromagnetic flow meter. The alternating iteration method is used in solving the problems. In experiments, the traditional symmetrical design is changed by daubing electrodes and plastering tinsel on inner wall of the flow meter. Calibrated data are compared with theoretical ones. The results are useful to engineering design and application of electromagnetic flow meters.
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B8B60DC0
A Novel Design Of A 12 Chords Ultrasonic Gas Flow Meter, Optimized For Performance Monitoring
Author(s): Jan G. Drenthen, Martin Kurth, Jeroen Van Klooster
Abstract/Introduction:
Over the past 15 years, thousands of ultrasonic flow meters have been successfully employed in the natural gas industry and in particular in the upstream and transmission segments. Here, the users take the full advantage of the non-intrusive measurement technology, the absence of pressure drop and the virtual maintenance free operation almost to the level of install-and-forget. Whereas in the early 90s the key issues with ultrasonic meters were in the first place the measurement accuracy and in the second place the applications, some 15 years later this has been shifted towards performance monitoring accuracy is nowadays almost taken for granted.
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Document ID:
13DD49D0
A Novel Ultrasonic Flowmeter For LNG With Fiscal Accuracy
Author(s): Jankees Hogendoorn, Andre Boer
Abstract/Introduction:
As recent development in the oil & gas market, an increase in the demand for fiscal measurement of Liquefied Natural Gas (LNG) at cryogenic conditions is observed. For more than ten years now, Ultrasonic flowmeters for fiscal measurement of liquid hydrocarbons have been applied successfully 1,2. In the past years, much experience has been gained and ultrasonic flowmeters can be considered as proven technology in this field 3. But beside successful applications at normal operating conditions, the ultrasonic measurement principle in itself is very suited for high accuracy flow measurement at cryogenic conditions as well. However, the development, construction and calibration of an ultrasonic flowmeter for fiscal measurement of LNG is not trivial. In this paper the development of an Ultrasonic flowmeter for the fiscal measurement of LNG shall be presented. This shall be done by addressing the following items: Transducer design Flowmeter design Calibration Concept Tests on liquefied Nitrogen Results This paper finishes with some conclusions and the discussion which steps to be taken in the next future.
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Document ID:
6D1A9491
Application Of Ultrasonic Flow Measurement Technology To Past And Future Generations Of Nuclear Power Plants
Author(s): Herb Estrada, Ernie Hauser, Gregor Brown
Abstract/Introduction:
This paper will describe the application of flow instruments based on the measurement of the transit times of ultrasonic pulses to nuclear power. It will cover the early history of the technology including the measurement, in 1975, of reactor coolant flow and temperature at Prairie Island Unit 2, as part of the generic design verification of a Pressurized Water Reactor coolant system design. It will also describe experience in the measurement of feedwater flow for the calorimetric determination of plant thermal power, including use of transit time systems for Measurement Uncertainty Recapture power uprates. Finally, plans for the application of ultrasonic flow measurement technology to both evolutionary and advanced reactor designs will be described.
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Document ID:
6F4D527F
Changes In Recently Revised AGA Report No.9 Measurement Of Gas By Multipath Ultrasonic Meters
Author(s): An Quraishi
Abstract/Introduction:
AGA Report No. 9, Measurement of Gas by Ultrasonic Meter, the first ever such report, came out in 1998. Since then additional knowledge were gained on meter performance through multiple research work and field experience. Manufacturers were also able to fine tune their products through innovation. The revised edition reflects changes required in consideration of those knowledge and innovations. Some of the changes are substantive while others are minor.
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1C36781A
Installation Effects Of A Multi-Path Ultrasonic Meter By Flow Simulation And Experiments
Author(s): Fong-Ruey Yang, Jian-Yuan Chen, Jiuun-Haur Shaw , Cheng-Tsair Yang, Jeng-Zen Fang , Ze-Wei Wang, Kun-Hai Lin, Tsai-Wang Huang
Abstract/Introduction:
Ultrasonic meters are used for custody transfer of natural gas since the AGA 9 was published in 1998. Recently, CPC cooperation, Taiwan entrusts Center for Measurement Standards (CMS) to investigate a modular design of a field-use ultrasonic metrology package. The purpose of this paper is to demonstrate partial results of the investigation on flow-filed effect on metering accuracy by using numerical and experimental approaches. The meter was installed downstream of an out-of-plane 150mm single elbow following a 400mm header. Averaged velocity of the meter is integrated over averaged velocities of all paths by applying suitable integration technique. With a typical case of flow conditioner installed 3.5D downstream of the 90 elbow, the flowrate metering deviated smaller than 0.6% except at the right downstream to the conditioner, say 2.5%. While in the experiments, an Instromet Q.sonic-3 meter placing 3.5D-43.5D downstream of an elbow showed error for each test scenario lie within 0.8%, with and without a flow conditioner. The results imply the validation of the simulation model and provide pipeline guide for further designing modular package.
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Document ID:
536EC112
Mechanical Thermal Expansion Correction Design For An Ultrasonic Flow Meter
Author(s): Emil Martinson, Jerker Delsing
Abstract/Introduction:
Ultrasonic measurements are commonly used today and one of the areas is in flow measurements 1. When measuring fluid velocities the equipment might get exposed to apparent changes in temperature, ambient or in the fluid, and this fact raises a number of issues. Several parameters that affect the measurement results are temperature dependent, e.g. flow velocity, fluid density, fluid viscosity and thermal expansion in materials 2. In this paper the effects of thermal expansion are considered and how to reduce the error they might give on performed measurements.
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Document ID:
8D426E7A
Comparisons Between Horizontally Installed Standard And Non-Standard Flange Tapped Orifice Plate Meter Wet Gas Flow Responses
Author(s): Richard Steven, Charlie Britton, Joshua Kinney
Abstract/Introduction:
Wet gas flow metering is an important problem in many industries and due to economic necessity many wet gas flows are metered by single phase gas differential pressure (DP) flow meters. A common DP meter design is the orifice plate meter and it is therefore one of the most widely used meters with wet gas flows. The early orifice meter horizontal flow wet gas research is well documented but in the last decade Venturi and cone type DP meters have been favoured as orifice plates were assumed to dam the liquid phase and therefore give relatively unstable DP readings. However, recent data analysis 1,2 suggests that standard orifice meter wet gas flow readings are not significantly affected by liquid build up and the readings are stable and correctable. Even so, it has been suggested by some engineers that liquid hold up by a plate could still potentially be a problem at low pressure and low gas flow rates.
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62EC63EC
The Performance Of Flow Nozzles At High Reynolds Number
Author(s): Michael Reader-Harris, Jeff Gibson, David Hodges, Ian Nicholson, Ronnie Rushworth
Abstract/Introduction:
Throat-tapped flow nozzles are used for power-station performance tests, and the accuracy of measurements is therefore of great importance because of the major financial implications of mis-measurements. The performance of Venturi tubes in high-pressure gas has proved to be different from what had been expected on the basis of calibrations in water at lower Reynolds number15. The aim of this project was therefore to calibrate throat-tapped flow nozzles in water and gas and to compare the results with those given in ASME PTC 6 and thus to see how well extrapolation from a water calibration to higher Reynolds number works. Wall tappings were also inserted so that data taken with wall tappings could be compared with those taken with throat tappings. The aim of this part of this work was to check the uncertainty claim for the discharge-coefficient equation for low-ratio long-radius nozzles in ISO 5167-37.
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Document ID:
26713391
New Method For The Characterization Of Flow Profiles
Author(s): T. Lederer, m. Dues, U. Muller, H. Baumann, F. Adunka, G. Wendt
Abstract/Introduction:
Testing of water and heat meters 1 refer to different kinds of flow profiles, like a fully developed turbulent flow profile or to disturbed flow profiles, which are generated using flow-disturbers like a swirl generator or a diaphragm. This approach arises a complex set of questions, as how an undisturbed flow profile can be characterized (theoretically and experimentally), and from which point on an undisturbed flow profile is no longer undisturbed? how do the flow profiles in the test benches from National Metrology Institutes (NMI) look like, and are they comparable to the flow profiles of test benches of manufacturers? how do the flow profiles downstream flow disturbers look like, and represent these disturbed profiles real flow configurations? And last but not least: how a flow profile can be measured quick, cheap and non-invasive? To achieve first results a cooperation project of Europes leading NMIs for flow measurement, PTB (Germany), METAS (Switzerland) and BEV (Austria) together with two small spin-off enterprises (ILA Inc. - Germany, OPTOLUTION Inc. - Switzerland) was founded in 2005.
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Document ID:
2BAF1911
Water Mass Measurement In Parts For Volume Standard Calibration In The Key
Author(s): Valter Yoshihiko Aibe
Abstract/Introduction:
This work describes the procedures used in the CIPM Key Comparison Volume comparison (CCM.FF-K.4) at the National Metrology Institute of Brazil (Inmetro). Two types of Transfer Standards (TS) were used, three 20dm3 metal pipettes and six 100cm3 glass pycnometers. Although Inmetro possesses a 60 kg comparator balance with a resolution of 0.01 g, the absence of a centralizer platform prevented its use in the calibration of the 20dm3 pipettes. Therefore, a smaller, 5 kg balance with 0,0 lg of resolution was used instead. The results obtained with the smaller balance were better than it would be possible with the larger, 60 kg balance. In order to measure a 20 kg water mass using a 5 kg balance, the water mass was distributed into 5 recipients. These were weighted separately, so that the total water mass was obtained by summing the masses up. A procedure was used to minimize and to account for water loss and evaporation. Although a simpler and cheaper instrument than the comparator balance was used, excellent CCM.FF-K4 results were obtained, as published in Arias et al (2006) 1.
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Document ID:
28F40E15
Low-Speed Measurements Using A Hot-Wire Anemometer
Author(s): Pier Giorgio Spazzini, Valentino Todde, Mats Sandberg
Abstract/Introduction:
In the present work, a method for calibrating hot-wire anemometers for low-speed measurements is described. After a brief recall of the working principle of the instrument, the problems connected with the measurement of low-speed flows are described. A method for overcoming these problems is proposed, and the special features of the specific calibration are discussed. Two different mathematical treatments of the calibration data are analyzed and compared. Finally, some test measurements are presented, showing that the results are in line with the expectations.
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5A3A3C5F
Development Of A Tracer Method To Check Flow Meters In Natural Gas Based On Accurate Speed-Of-Sound Determination
Author(s): H.J.Riezebos, G.J.van Essen, J.P.Mulder, L.van Luijk, Mp. Van Der Beek, S. Hagendoom A.J.M.Herwijn, A.M.H. Van Der Veen
Abstract/Introduction:
A method has been developed to perform in-situ checks on flow metering equipment for fiscal metering purposes in natural gas. This method has large advantages as compared to traditional methods of checking flow metering equipment. Traditionally, the performance of flow meters is checked after build-out and transport to a calibration facility where they are calibrated against the high-pressure natural gas flow standards. This procedure is costly and does not always give the desired results, in particular in cases where upstream conditions like swirl or pulsations influence the meter reading.
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27F4AABA
Model-Based Fluid Diverter Analysis For Improved Uncertainty Determination In Liquid Flow Calibration Facilities, Exemplified With Ptbs Hydrodynamic Test Field
Author(s): Rainer Engel, Hans-Joachim Baade
Abstract/Introduction:
In liquid flow calibration facilities, run in the flying-start-and-finish operation mode, a diverter represents an essentially accuracy determining functional unit, both with gravimetric and volumetric reference based installations. Model-based approaches that describe a diverters operation on the basis of realistic diverter flow conditions and kinematics of the diverting edge provide capabilities to take into account component related and flow related effects and processes for both a comprehensive diverter operation and uncertainty analysis model. Based upon this dedicated knowledge of a special diverter design this approach is applicable even if there are only minimum information on diverter characteristics available with worst-case assumptions being applied.
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Document ID:
4BAC1927
A Specification And Uncertainty Evaluation Of A High Reynolds Number Calibration Facility
Author(s): Noriyuki Furuichi, Yoshiya Terao, Masaki Takamoto
Abstract/Introduction:
A new test facility has been constructed at National Metrology Institute of Japan (NMD) for calibration of feed water flowmeters used at nuclear power stations at Reynolds numbers of up to 18 million. This very large Reynolds number is achieved at a flow rate of 3.33 m3/s (12 000 m3/h) and water temperature of 70 C in a 600 mm pipe. The DUT (Device under test) calibration is carried out by comparison method with reference of the working standard which is calibrated by the weighing tank and the ball prover system. This working standard is traceable to the national standard of water flowrate in Japan. The expanded uncertainty of this facility is 0.077% (k 2). This paper describes the concept of the new facility, calibration method and the fundamental uncertainty estimation.
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D5D9D07A
Automated Primary Flow Calibration
Author(s): Harvey Padden
Abstract/Introduction:
Dissemination of quality calibrations has always been of critical importance. For many types of calibrations, proper application of instruments is the most important factor in maintaining the quality of field calibrations. This is particularly true in the case of gas flow calibration. Shippable primary standards exist, but proper application is still an important issue. Interestingly, we, the makers of precision primary gas flow calibrators, face the same problem as our users. If we include our less expensive primary provers, we have the problem of assuring quality control of thousands of calibrations per year on a production basis. So, to paraphrase the ancients, who will prove the provers? This is a problem that will become more common as other primary and high-accuracy devices are migrated from the lab to field use. While relatively simple for such artifacts as gauge blocks or voltage standards, it is a very complex problem for primary flow provers. How, then, to automate measurement of piston leakage tare, as well as high-accuracy flow comparisons with master devices at a variety of flow rates on an automated basis, assuring maintenance of calibration quality? We have designed a system for our internal use that valves various flows to devices under test while keeping inventory volume to the low, required value, along with the control circuitry to interface all the devices to master DryCal provers. Here we discuss the process, and design considerations in detail.
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Document ID:
D6590059
Calibration Of A Cup Anemometer On A Rotating Arm Rig
Author(s): Riccardo Malvano, Pier Giorgio Spazzini, Aline Piccato
Abstract/Introduction:
The present work deals with calibration of cup anemometers. I.N.Ri.M. uses wind tunnels for anemometer calibration at high speeds, but this kind of test rigs is not appropriate for the calibration at low speeds, in particular for determining the instrument threshold. For this kind of measurements, a test rig consisting in a rotating arm (which allows long run times at nominal speeds in the range from 0.20 to 5.0 m/s) is used. Due to their working principle, cup anemometers react to the rotating environment in a different way with respect to their response to an analogous stimulus in a uniform flow. Though, it is possible to theoretically compute this difference and to derive a correction formula. A mathematical derivation of the correction formula is shown for a simplified case together with experimental results, in order to show the extent of the problem and the validity of the solution proposed.
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Document ID:
A398CE8C
Development Of A 500 Slm High Speed Piston Prover
Author(s): Harvey Padden
Abstract/Introduction:
Piston provers have traditionally been used for flows below approximately 50 slm. Above that level, bell provers, which are much slower and less convenient to operate, have been used. We sought to experimentally establish the feasibility of very high-speed viscous-sealed piston provers for flows up to 500 slm. The difficulties to be overcome in building a prototype included: Constructing a 152 mm by 600 mm piston-cylinder pair with a clearance of approximately 25 microns along the full stroke Procuring valves with low enough restriction (Cv) to allow gravity reset Detecting piston position optically Accounting for effects of the pistons low resonant frequency and other dynamic effects We constructed such a prover and conducted numerous experiments to characterize the internal pressure (hence, piston motion) characteristics during the cycle. The prototype was then tested at NIST against sonic nozzles over a flow range of 10 slm to 500 slm. The prover exhibited linearity agreement to approximately 0.04%, with 0.05% or better reproducibility in a second run. Based upon these data and upon further uncertainty analyses, our conclusion is that very high speed 500 slm provers can be constructed with combined standard uncertainties of better than 0.1%.
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Document ID:
30056CB6
Comparison Test Between The Light Oil Flow Standard System And Calibration System By Using The Turbine Flowmeter Package
Author(s): Ki Won Lim
Abstract/Introduction:
A Light Oil Flow Standard System (LOFSS) at the Korea Research Institute of Standards and Science (KRISS) was established as a primary national standard system for a hydrocarbon flow. The expended uncertainty of the flow quantity determination was estimated as 0.04 %. The calibration of the oil flowmeter used for the transaction and process control in industry was a main reason for the establishment of LOFSS. Practically, the measuring conditions, which were highly influential on the flowmeter characteristics, were different. In particular, the physical properties of the fluid including the density and the viscosity were affected by the stability of the fluid temperature under varying flow conditions. In addition, the calibrators used in industry varied and included a gravimetric device, a piston prover and a master meter calibrator.
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Document ID:
218D2E6D
Uncertainty Of The Critical Venturi Transfer Standard Used In The K6 Gas Flow Key Comparison
Author(s): John D. Wright
Abstract/Introduction:
The uncertainty of a critical flow venturi (CFV) gas flow transfer standard with dedicated, redundant pressure and temperature instrumentation is analyzed. At lower flows (5 g/min), the standard uncertainty of the transfer standard was 0.026 %. At higher flows (200 g/min), the standard uncertainty was 0.019 %. The largest uncertainty components were: 1) environmental temperature effects, 2) pressure sensors, and 3) the critical flow function. Temperature effects for the CFV transfer standard resulted from: 1) temperature sampling errors, 2) thermal boundary layers, and 3) thermal expansion of the CFV throat. Temperature effects on small CFVs were more significant than for large CFVs.
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3ECBB9FD
Trilateral Comparison Of Static Volume: Inimet, Ptb, Inmetro
Author(s): Franco J., Maury A., Espinosa G., Alonso N., Tobben H., Dopheide D., Dalni.S. Filho, Jose J.Pinheiro
Abstract/Introduction:
The comparison among the primary standards of the different countries, is one of the essential activities of the National Metrology Institutes (NMI), and constitutes one of the main ways for confirm the technical competence of the laboratories and its also a requirement for publication of the CMCs in the KCDB of the BIPM. The measurements of volume are the base of the custody and transfer of the hydrocarbons, thats the background for the importance of the traceability to the national standards and the proven equivalence of these to the international ones. The participant laboratories INIMET, PTB and INMETRO are the primary laboratories responsible to maintain and disseminate the units of volume and flow of liquids respectively in Cuba, Germany and Brazil. Cuba and Germany are members of COOMET, the last one is also member of EUROMET and Brazil belongs to the SIM. PTB and INMETRO participated in a key comparison of volume of the CIPM conducted in 2005, CCM.FF-K4 with highly satisfactory results.
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Document ID:
0B1AFB07
Euroloop: Unique Oil And Gas Calibration Facilities
Author(s): Wim Volmer
Abstract/Introduction:
NMi is currently building two large calibration facilities: one for meters intended for oils and oil products and one for meters designed for natural gas. After giving a brief overview of the capabilities of both facilities, the presentation will mainly cover the gas facilities layout, specifically those aspects concerning traceability, and the innovative design of the liquid provers, which includes real-time leak detection.
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Document ID:
035D7C08
Numerical Simulation Of Flow In Stator Of Turbine Flow Meter
Author(s): U. Banaszak , E. Von Lavante, K. Van Dellen
Abstract/Introduction:
It is well known that the flow conditioner in the front part of a typical turbine flow meter, frequently called stator, has a significant effect on the meter accuracy. Recently, several new designs that achieve effective flow conditioning have been introduced. In the present work, it was decided to investigate the flow field in several such flow conditioning devices by employing numerical flow simulation. Two of these configurations will be discussed presently in more detail, focusing on their effectiveness to reduce incoming swirl.
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3BA6C1EA
Effects Of Shape Change Due To Wear On The Accuracy Of Vortex-Shedding Flow Meters
Author(s): E. Von Lavante, U. Banaszak, m. G. Yilmaz, O. Ricken
Abstract/Introduction:
In the present investigation, the problem of accurate determination of volumetric flows by means of the socalled vortex-shedding flowmeter in the case of shape changes from the original specifications due to wear was studied. To this end, the flow about the bluff body used in the presently studied vortex-shedding flow meter PROWTRL 72, as manufactured by the Flowtec AG, was investigated experimentally and numerically using a solver of the unsteady, compressible Navier-Stokes equations in two dimensions. The computations were carried out for several Reynolds numbers using modified geometry in which rounded edges of different radii, representing wear, were introduced. The effects of turbulence were modeled by using the realizable k-e turbulence model. The resulting flow fields were analyzed using various methods, including visualization, evaluation of several of their global features and DFT of properly chosen variables. The experimental results, obtained for a model bluff body using an ultrasound barrier for determination of the vortex shedding frequency were validated by comparison of measurements carried out on a real flow meter.
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Document ID:
2C9ADF79
Development Of The National Standard Facility For Hydrocarbon Flow At 0.1 To 15m3/h
Author(s): Ryouji Doihara, Takashi Shimada, Yoshiya Terao, Masaki Takamoto
Abstract/Introduction:
The NMIJ has constructed a new calibration facility in order to establish the national standard for hydrocarbon flow at 0.1 to 15 m3/h. This middle-size oil flow primary standard facility applies a static and gravimetric method with flying start and finish. A rotating double wing diverter (RDWD) and an improved weighing tank system have been developed for this new facility. After adjustment of the start and stop signal timings, the diverter timing error was certain to fall within 1 ms.
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Document ID:
9FF6BE60
Dynamic-Weighing Liquid Flow Calibration System - Realization Of A Model-Based Concept
Author(s): Jesus Aguilera, Rainer Engel, Gudrun Wendt
Abstract/Introduction:
The aim of this paper is to present the first experimental results of a new principle to measure liquid flow by applying a dynamic-weighing approach, which is being implemented in the PTB Hydrodynamic Test Field 1. This new measurement principle relies on a physical analogous model comprising fluid, mechanical and electromechanical elements. They are basic elements representing the model-based approach 3, where appropriate real-time processing and synchronized data acquisition play particularly an important role to reproduce the instantaneous liquid flow rate. Concerning fluid-structure interaction, an exploratory research was conducted to identify the type of forces present in the process, their occurrence and effect upon the system elements to determine the instantaneous flow rate. Some of these system state variables turn out to be measurable and some others, due to their nature, are just assumed as disturbances. For modeling purposes such forces and elements are only possible to be analyzed in terms of their basic form as: sources of excitation, solid and fluid oscillators.
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Document ID:
EC6CFCB1