Miroslava Benková, František Schweitzer
The Czech Metrology Institute continues in development of a method in the area of very small flows of liquid aimed at reducing uncertainties and expanding flow to lower values. The primary standard developed based on mass method has successfully been internationally compared and the results have shown data stability. With increasing accuracy of flow meters on the market, requirements for reduction of uncertainty of primary or secondary standards are rising. In case of very small flows, i.e. below 10 ml/h, some calibrations and subsequent result evaluations by means of the weighing method...
J. Sluse
Disturbing parts situated on upstream of the flowmeter have influence on inlet velocity field. This change on the inlet of the flowmeter may influence measurement accuracy of the flowmeter. The aim of this article is to determine influence of disturbing parts on the measurement. Typical disturbing part situated on upstream of the flowmeter is elbow, swirl, half-plate, valve etc. The influences will be determined the standard for cryogenic flow rate measurement using LDV which was developed for measurement of the flow rate of liquefied natural gas (LNG) and other cryogenic fluids. The...
Y. Arellano, A. Hunt, O. Haas, H. Ahmed, L. Ma
Despite intensive research dedicated to multiphase flow measurement in the past decades, accuracy remains one of the key challenges in the oil and gas industry. The Multiphase flow of gas-liquid mixtures has been extensively addressed in the literature. However liquid-liquid flows, are intrinsically more complex and their hydrodynamics are not yet completely understood. The present study investigates the capabilities of in-line tomography technologies for water cut determination in co-current immiscible liquid-liquid flows. The proposed experimental metering system operates by interrogating...
M. A. Silva,, D. Loureiro, A. S. Ribeiro, C. Amado
The flow measurement is essential for drinking water network monitoring. A better knowledge about the flow that is abstracted or pumped to drinking water systems, transferred between water utilities or monitored at the entrance of the subsystems can be achieved through the flow measurement. Nevertheless, this is a topic insufficiently studied. The accuracy can be an excellent parameter to the analysis of the uncertainty sources impact on the measurements obtained from manufacturer’s catalogues, and the contributions related with installation, data acquisition, transfer, storage and...
S. Knotek, J. Geršl, A. Paták
The article presents the modeling of SO2 diffusion into water droplet and water film which arise in dryers by condensation or evaporation in dependence on physical and chemical conditions. The motivation of the modeling is the attempt to quantify the SO2 loses in drying during sampling of emissions. The basic processes of gaseous substances dissolution into liquid are discussed theoretically and quantitative results of computer computations are presented.
Y. Liu, X. Feng, Y. Yao, L. Lei, P. Zhao, T. Meng, L. J. Huang
Calibration of a microfluidic meter is conventionally done with a precision reference such as a high accurate balance or a precise syringe pump system. These processes normally are very time consuming and are not the feasible approaches for high volume flow meter manufacture. In this paper, we will discuss the comparison of the calibration options of the thermal time-of-flight microfluidic meter including the precise syringe system, balance and Coriolis flow meter. The flow range of the meter covers from 20μL/min to 400mL/min. The comparison of the metrology features and the procedure of...
Heming Hu, Yuan Liu, Zhigang Wang, Zeyu Guo, Yunlong Zhu
Current meters are used for flow velocity measurement in river and ocean. Accurate measurements need accurate calibrations. There are more than ten tow tank facility in China providing water velocity calibration, and all of them are ~ 100 m long concrete tank with no clear uncertainty budget, especially there is not a thorough understanding of the water movements in the tow tank. We have built a small tow tank which is 8 m long, 1.2 m wide and 1.2 m high with a cart running speed of 0.01m/s ~ 1m/s. It was made of transparent glass and was possible to use optical instruments to investigate...
B. W. Sims, J. A. Brandt, R. J. McKee
The discharge coefficient, Cd, for a Critical Flow Venturi Nozzle (CFVN) corrects the theoretical mass flow to the actual mass flow at measured inlet conditions. The theoretical mass flow is calculated using 1-D isentropic theory and does not account for the subsonic boundary layer along the CFVN wall. For a precisely known throat area, Cd must be less than unity due to this boundary layer. Theory predicts that the geometry of the inlet to a CFVN will affect the boundary layer and therefore effect the Cd. This effect on Cd becomes more significant for smaller CFVNs which are operated at...
D. van Putten, L. H. van Luijk, H. J.Riezebos, B.Tinge
For increasingly complex production systems, the traditional allocation processes appear to be less suitable and an alternative methodology is required. An assessment was carried out on a large wet gas allocation system containing more than 120 wells. The assessment was based on an approach that combines the Data Validation and Reconciliation (DVR) methodology and process simulations to accurately calculate the reconciliation factors applied to each well. It was found that the current imbalance and the allocation method complies with requirements stated in the agreement between stakeholders....
E. M. Graham, M. Reader-Harris, G. Chinello, K. Harkins, N. Bowman, L. Wales
Venturi tubes are commonly used for wet-gas flow measurement, and the majority of commercial wet-gas flow meters generally include a Venturi tube installed vertically with embedded secondary instrumentation. The presence of the liquid causes an increase in the measured differential pressure and results in the Venturi tube over-reading the actual amount of gas passing through the meter. Most of the research in the literature is focused on the investigation of the over-reading for horizontally oriented Venturi tubes, thus limiting the development of over-reading correlations for vertical...