Metrological performance investigation of swirl flowmeter affected by vortex inflow

2019 ◽  
Vol 33 (6) ◽  
pp. 2671-2680 ◽  
Author(s):  
Qi Liu ◽  
Jia-hui Ye ◽  
Guang Zhang ◽  
Zhe Lin ◽  
Hong-guang Xu ◽  
...  
Keyword(s):  
Metrological Performance

A fuzzy evaluation method of road vehicle automatic weighing instrument in dynamic force metrological performance

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1365-1372
Author(s):  
Xiaohui Mao ◽  
Liping Fei ◽  
Xianping Shang ◽  
Jie Chen ◽  
Zhihao Zhao
Keyword(s):  
Evaluation Method ◽  
Comprehensive Evaluation ◽  
Evaluation Model ◽  
Dynamic Performance ◽  
Dynamic Force ◽  
Fuzzy Evaluation ◽  
Road Vehicle ◽  
Evaluation Standard ◽  
The Road ◽  
Metrological Performance

The measurement performance of road vehicle automatic weighing instrument installed on highways is directly related to the safety of roads and bridges. The fuzzy number indicates that the uncertain quantization problem has obvious advantages. By analyzing the factors affecting the metrological performance of the road vehicle automatic weighing instrument, combined with the fuzzy mathematics theory, the weight evaluation model of the dynamic performance evaluation of the road vehicle automatic weighing instrument is proposed. The factors of measurement performance are summarized and calculated, and the comprehensive evaluation standard of the metering performance of the weighing equipment is obtained, so as to realize the quantifiable analysis and evaluation of the metering performance of the dynamic road vehicle automatic weighing instrument in use, and provide data reference for adopting a more scientific measurement supervision method.

The method of determining the metrological performance of unit reference standards of reflection coefficient in waveguides at millimeter waves

2020 ◽  
pp. 59-63
Author(s):  
A.S. Bondarenko ◽  
A.S. Borovkov ◽  
I.M. Malay ◽  
V.A. Semyonov
Keyword(s):  
Reflection Coefficient ◽  
Millimeter Waves ◽  
Primary Standard ◽  
Reference Standards ◽  
Measurement Scale ◽  
Current State ◽  
Coefficient Measurement ◽  
Mathematical Equations ◽  
Electrodynamic Modeling ◽  
Metrological Performance

The analysis of the current state of the reflection coefficient measurements in waveguides at millimeter waves is carried out. An approach for solving the problem of reproducing the reflection coefficient measurement scale is proposed. Mathematical equations, which are the basis of the reflection coefficient measurement equation are obtained. The method of determining the metrological performance of reflection coefficient unit’s reference standards is developed. The results of electrodynamic modeling and analytical calculations by the developed method are compared. It is shown that this method can be used for reproducing the reflection coefficient unit in the development of the State primary standard.

Study on the metrological performance of self-calibration angle encoder

2016 ◽  
Author(s):  
Yao Huang ◽  
Zi Xue ◽  
Dan Qiao ◽  
Yan Wang ◽  
Chunran Yue ◽  
...  
Keyword(s):  
Self Calibration ◽  
Angle Encoder ◽  
Metrological Performance

Numerical simulations for swirlmeter on flow fields and metrological performance

2016 ◽  
Vol 40 (4) ◽  
pp. 1072-1081 ◽  
Author(s):  
Desheng Chen ◽  
Baoling Cui ◽  
Zuchao Zhu
Keyword(s):  
Vortex Core ◽  
Reverse Flow ◽  
Pressure Fluctuations ◽  
Flow Characteristics ◽  
Turbulence Models ◽  
Internal Flow ◽  
Industrial Applications ◽  
Throat Region ◽  
Vortex Precession ◽  
Metrological Performance

Measurements of flow rates of fluids are important in industrial applications. Swirlmeters (vortex precession meters) are widely used in the natural gas industry because of their advantage in having a large measurement range and strong output signal. In this study, using air as a working medium, computational fluid dynamics (CFD) simulations of a swirlmeter were conducted using the Reynolds-averaged Navier–Stokes (RANS) and renormalization group (RNG) k–ε turbulence models. The internal flow characteristics and the influence of the tube structure (geometric parameter of flow passage) on metrological performance were studied, with a particular focus on the meter factor. Calibration experiments were performed to validate the CFD predictions; the results show good agreement with those from simulations. From the streamline distributions, a clear vortex precession is found in the throat region. At the end of throat, the pressure fluctuation reached a maximum accompanied by the largest shift in the vortex core from the centreline. There exists a large reverse flow zone in the vortex core region in the convergent section. To mitigate the influence of reverse flow on vortex precession, a suitable length of throat is required. For a larger convergent angle, the fluid undergoes higher acceleration leading to an increase in velocity that produces more intensive pressure fluctuations. The minor diameter of the throat also produces a higher velocity and larger meter factor. Compared with both divergent angle and throat length, the convergent angle and throat diameter play a more important role in determining precession frequency.

scholarly journals Weak-value amplification: state of play

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
George C. Knee ◽  
Joshua Combes ◽  
Christopher Ferrie ◽  
Erik M. Gauger
Keyword(s):  
Quantum Theory ◽  
Signal Amplification ◽  
Weak Measurement ◽  
Experimental Results ◽  
Weak Values ◽  
Theoretical Studies ◽  
Weak Value ◽  
Metrological Performance ◽  
Weak Value Amplification ◽  
Theory And Experiment

AbstractWeak values arise in quantum theory when the result of a weak measurement is conditioned on a subsequent strong measurement. The majority of the trials are discarded, leaving only very few successful events. Intriguingly those can display a substantial signal amplification. This raises the question of whether weak values carry potential to improve the performance of quantum sensors, and indeed a number of impressive experimental results suggested this may be the case. By contrast, recent theoretical studies have found the opposite: using weak-values to obtain an amplification generally worsens metrological performance. This survey summarises the implications of those studies, which call for a reappraisal of weak values’ utility and for further work to reconcile theory and experiment.

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