Klemen Rupnik, Jože Kutin, Ivan Bajsić
The axial heat transfer effects on the performance of the thermal dispersion mass flow meter are studied by employing an analytical one-dimensional model and a numerical two-dimensional model of the thermal flow sensor. The relationship between the measurement characteristic and the temperature difference between the sensing element and the base is analysed and possible methods to practically implement the correction of the measurement characteristic are proposed.
XXI IMEKO World Congress
· TC9
· 2015
· Download
Jeerasak Pitakarnnop, Rugkanawan Wongpithayadisai, Sutham Masri
Sonic nozzles are wildly employed as a flow standard owing to their advantages in mechanical simplicity and long-term stability. The flow behaviours through the nozzles in normal conditions are well understood. However, in the applications where the size and the operating pressure are very small, the continuum assumption begins to break. Slip-flow, which is beyond the scope of ISO9300, becomes dominant. The scope of this study is to validate the method used to predict the effects in the nozzle.
XXI IMEKO World Congress
· TC9
· 2015
· Download
M. Neumayer, M. Flatscher, T. Bretterklieber
Pneumatic conveying has become one of the most favorable transport techniques for bulk solid materials. The metrological assessment of the flow parameters, e.g. mass flow, velocity, as well as the quantification of the flow regime is of crucial interest. However, the nature of the transport system makes measurements challenging. In this work we present an electrical capacitance tomography system for state of flow estimation and demonstrate the abilities of the system by means of test rig measurements.
XXI IMEKO World Congress
· TC9
· 2015
· Download
Zhang Xiaozhong, Meng Fanqin, Song Shengkui, Wang Jiehui
The mass flow measurement is generally necessary in light fuel oil delivery, but measurement value of the ultrasonic flow meter is volume flow rate, it cannot meet the requirement of mass flow measurement. In this paper, relationship between the light fuel ultrasonic velocity, fuel density and temperature is analyzed through a large number of experimental data, the neural network model of different light fuel density and temperature and its ultrasonic propagation velocity is found. By use of this network model, a method of mass flow measurement by a ultrasonic flow meter has been given....
XXI IMEKO World Congress
· TC9
· 2015
· Download
Pasquale Arpaia, Mario Girone, Annalisa Liccardo, Marco Pezzetti, Fabio Piccinelli
The assessment of the metrological performance of a virtual flowmeter-based transducer for helium under cryogenic conditions is proposed. At this aim, first a model of the transducer, mainly based on a virtual flowmeter exploiting Sereg-Schlumberger method and a valve model exploiting finite-element approach, is presented. The transducer and valve models are validated experimentally on a case study for helium monitoring in cryogenic systems at the European Organization for Nuclear Research (CERN). Then, a fully simulated approach is performed in order to assess the transducer performance. In...
XXI IMEKO World Congress
· TC9
· 2015
· Download
Dennis W. K. Lee, Aaron Y. K. Yan, Henry K. L. Chiu, Raymond W. M. Leung
This paper demonstrates different configurations of the SCL’s reference flow standard used in calibrating a mass flow controller at various line pressures, and elaborates on methods to improve the calibration efficiency and accuracy by using a back pressure regulator. This paper also studies the sensitivity of the reference flow standard to various line pressures. It is revealed that the deviation of relative reading errors is less than the uncertainties of the reference flow standard.
XXI IMEKO World Congress
· TC9
· 2015
· Download
Henrik Krisch, Ali Gedikli, Ernst von Lavante, Pouya Mirzaei
The present publication describes a new design of a flow meter for metering fluids using fiber sensing methods. Mach-Zehnder interferometer was implemented for the detection of the vortices. The signal generation is based on the frequency detection of a vibrating diaphragm placed in a specially optimized measuring chamber. The stress of the vibrating diaphragm is sensed using a Mach-Zehnder (MZ) fiber interferometer, with fiber arms fixed to the diaphragm. This solution allows measuring flow rates of liquids, gases and vapors with temperatures up to +700°C and pressures up to 300 bar....
XXI IMEKO World Congress
· TC9
· 2015
· Download
Zdeněk Krajíček, Martin Vičar, Dominik Pražák, Jiří Tesař, Tomáš Hajduk, Ladislav Peksa, Tomáš Gronych, Martin Jeřáb
The Czech national standard of low gas flow is based on a gravimetric flow standard (GFS) principle. It means it defines the flow as the mass loss of gas from a pressure bottle which is continuously weighed. This weighing is performed in an ambient atmosphere which causes that the main source of uncertainty results from the buoyancy correction. This buoyancy correction is complicated by the instabilities of the atmospheric environment and by the fact that volume of the weighed pressure bottle is dependent both on temperature and internal pressure. By modifying the experimental set-up of the...
XXI IMEKO World Congress
· TC9
· 2015
· Download
Satoshi Honda
This study analyzes an end-shorting effect on electromagnetic flowmeters with short distance between connecting flanges around about 5D or more. The Bevir’s formulation is extended to a conducting pipe wall. Through the evaluation of the Green function satisfying the corresponding boundary conditions, the author’s previous formula is reviced.
XXI IMEKO World Congress
· TC9
· 2015
· Download
Denis F. Hinz
We study the repeatability of laser-Doppler velocimetry experiments for pipe-flow analysis. For single-point velocity measurements, we find repeatability standard deviations of approximately 0.5 % in the core region whereas measurements close to the wall are de-facto unrepeatable. We discuss how repeatability data may be used to verify uncertainty budgets and how it could be included in revised uncertainty budgets in view of established guidelines such as GUM and ISO 21748.
XXI IMEKO World Congress
· TC9
· 2015
· Download