Hakan Kaykisizli, Dr.Vahit CiftCi, Ernur Karadogan, Basak Akselli
Turbine meter is a flow measurement device utilizes the angular velocity of rotating blades to measure the flow rate. Pulses for a known time period are counted by turbine meter counting mechanism. The total number of counts for a given time period is proportional to the volumetric flow rate of the turbine meter. National Metrology Institute of Turkey (UME) standard reference turbine meter pulse information is generated by a system called variable reluctance tachogenerator. This paper explains how mechanical movements of blades are converted to electrical signals and comparing the degree of...
E. von Lavante, N. Lazaroski, U. Maatje, T. Kettner, V. Lötz-Dauer
The complex three-dimensional unsteady flow field in a one-stage turbine gas flow meter was studied by carrying out numerical simulations using the Navier-Stokes solver Fluent. The simulation of all the viscous effects as well as secondary flows, such as the flow in the tip gap and secondary and tertiary vortices in the blade to blade region required a very high grid resolution. Therefore, a series of three-dimensional block-oriented hybrid grids containing between 300 thousand and 1.5 million grid cells was generated and implemented. The aim of the present project was to find the correct...
Kazuto Kawakita
Everyday, in many countries producers and importers supply larg e volumes of natural gas produced from domestic fields or purchased abroad. To attend to this need, a whole host of interlinked and co- ordinated activities and technical installations are required both on the purchase and the sales side. Besides the production and processing facilities, compression stations, transmission and distribution pipelines, operation and control stations, many measuring systems are necessary to quantify the huge volumes of gas commercialized among parts. Natural gas measurement sys tems can be found in...
A. Saglam, P. M. A. van der Kam, G. J. van Essen, D. H. Hebels
Gastransport Services in the Netherlands, uses turbine gas meters to measure the gas flow to local gas distribution companies, large industrial customers and power plants GTS operates approximately 1100 city gate stations, at a delivery pressure of usually 8 bar. In the Netherlands, the procedures for determining the operational performance of the turbine meters are agreed upon between Gastransport Services and its customers. As a result of this agreement, Gastransport Services inspects the total population of turbine meters by means of the well-known variables-acceptance-sampling. Each...
E. von Lavante, R. Kramer, B. Mickan
Detailed investigation of flow fields associated with sonic Venturi nozzles with extremely small Reynolds numbers used for flow metering was carried out. The range of Reynolds numbers considered in this work extended from Re = 323 to Re = 452. In the experimental part, global parameters such as discharge coefficient C d were investigated independently for two different diameters, d = 25 µm and d = 35 µm. Both discovered flow phenomena that were not explainable using simple linear theories. Therefore, in the numerical part of the present investigation, the corresponding flow fields were...
Gabriel Moniz Pereira, Bodo Mickan, Rainer Kramer, Dietrich Dopheide, Ernst von Lavante
It is a well-known and recognised fact that the behaviour of flow rate and volume measuring devices can be affected very strongly by the flow conditions prevailing in their inlet pipe section. Disturbed velocity profiles caused by pipe configurations such as bends, headers, pressure regulators and convergent or divergent pipe sections in front of a flow meter can lead to deviations of the meter reading by up to several percents. Thus, flow conditioning normally means the generation of fully developed flows in the inlet of meters to avoid installation effects. Since this is in practice not...
Douglas Baumoel
Recent advances in externally mounted sensor design and related electronics have enabled gas meters using clamp-on, non-intrusive, ultrasonic transducers to provide performance equal to or better than meters using conventional insert transducer technology. It is acknowledged that this claim will be met with skepticism; however, the following pages provide evidence of this performance capability. This paper also presents the technical challenges to this design, and how they were overcome. We will review the applicability, benefits, and limitations of the various configurations of this...
Torbjörn Löfqvist, Kestutis Sokas, Jerker Delsing
This paper concerns speed of sound measurements performed in three different gas mixtures at constant temperature and pressure while the concentration of the gases was varied. The performed experiments used an ultra sonic, sing-around, gas flow meter equipped with silicon based transducers. The center frequency of the transducers was 800 kHz. Speed of sound was measured in mono-, di- and triatomic gases: argon (Ar), oxygen (O 2 ) and carbon dioxide (CO 2 ), in either air or nitrogen (N 2 ) as a background gas. The gas under investigation was mixed with the background gas in a test chamber...
Sampo Sillanpää, Martti Heinonen
Due to the increasing need for traceable gas flow measurements in Finland, the development of a national measurement standard for gas mass flow was initiated at the Centre for Metrology and Accreditation (MIKES) in 2002. A primary calibration system based on dynamic weighing was constructed to provide traceability directly to the national mass and time standards. The MIKES gas flow measuring system includes also a commercial calibrator based on laminar flow elements. It is used as a working standard when calibrating mass flow meters for customers. The calibration range encompasses 0,4 mg / s...
Noel Bignell
A previous study (Bignell and Choi, Flow Meas. & Instrum. 13 (2002) 17-22) of the effect of temperature on the coefficient used to characterise small sonic nozzles is reviewed. Adiabatic cooling of the gas stream in the throat causes the body of nozzles to be cooled but a heater and temperature control system allow the temperature of the nozzle to be held constant. Using a gas flow standard that can operate in continuous mode, measurements were made of nozzle coefficients at different temperatures using air, argon, nitrogen and carbon dioxide. The nozzle coefficient changes with the gas type...