IMEKO Event Proceedings Search

Page 13 of 912 Results 121 - 130 of 9113

L.Saidoripov, A. Stetsenko, Y. Glova, V. Naumenko, O. Ukolov
Development of a national standard of water consumption in the Republic of Uzbekistan

The problem of water resources in Central Asia and, especially, in the Republic of Uzbekistan, requests to keep a high-quality and accurate accounting of water and/or liquid consumption using water flow meters of various types, classes and modifications. In turn, there is a need (in the Republic of Uzbekistan - once every two years) to verify and calibrate liquid flow meters, using a specific verification facility. Following the Resolutions of the President of the Republic of Uzbekistan No. PP-2935 dated April 28, 2017, and No. PP-4059 dated December 12, 2018, on December 2018 № PP-4059 for the development of the national standard base of the Republic of Uzbekistan State Institution "Uzbek National Institute of Metrology" (SI "UzNIM") in cooperation with the Agency on Technical Regulation the specifications have been developed for the delivery of Automated verification rig for flow meters, liquid meters (hereinafter referred to as - the rig) for the needs of the SI "UzNIM", approved on January 29, 2019.

H. Hu, Z. Cheng, P. Gruber, Z. Wang
Ultrasonic Transit-time Discharge Determination in Rectangular Open Channel

Ultrasonic Transit-time method is a good choice to measure the open channel discharge. To investigate its performance in the rectangular open channels, a 26 m long, 2 m wide, 1.2 m deep open channel facility was built with an over-fall head tank providing a very stable flowrate of 1.5 m³/s in maximum and 39 typical cases were tested. The tested results verified that ultrasonic transit-time method can be well used to measure the discharge in rectangular open channels. However, due to unavoidably disturbing the flow patterns and introducing some errors, thus the transducers should be made as small as possible to improve the measuring accuracy. In addition, more paths should be used to produce smaller errors. And at least two paths are suggested to be mounted in the range of hi/H > 0.7 to better reflect the influence of the free surface. Comparing sub-discharges in all zones, it can be found that substantial differences between mean-section method and Giordano Law exist below the lowest path. Larger Kb, for example 0.9, makes mean section method produce closer measurements to Giordano Law.

Dannal Cheng, Feng Gao, Junfeng Mao, Shi Wu, Xinli Dong, Han Zhang, Qian Zhang
Probe into methods about the comparison of gas flowmeters

At present, the way to check the flowmeter accuracy is disassemble them and send to flow lab and verify it. But customer don’t like it, because it will affect or stop their production. What the customer really need is toknow the meter accuracy but non-disassemble flowmeters. It is not an easy way, this paper describes a feasible solution about inline comparison of gas flowmeter by inline drilling, inline installation, power supplyand data recording & analysis. In the end, cited a field case about comparison of gas flowmeter.

Wang Lei, Zhang Yinan, Liu Yuan, Meng Tao
Remote Calibration Research of Large Flow Samplers

In recent years, calibration demands of automatic monitoring stations for atmospheric radiation environment inChina are increasing. However, large flow samplers in monitoring stations are relatively large, so dismountingand transportation will result in significant cost. While the monitoring stations may be dozens or evenhundreds of kilometers apart and the cost of field testing is too high, so the values couldn’t be guaranteed. Inthis paper, a set of remote calibration device for large flow samplers based on master meter method is developed, which is a fully automated calibration system. Sealing test and mutual verification test of double master meters are designed. Besides, an intelligent video recognition system, a control terminal of field tests and a remote monitoring platform are built to fully guarantee authenticity and effectiveness of remote data. Key Words: remote calibration, large flow samplers, master meter method, intelligent video recognition system, control terminal of field tests, remote monitoring platform

Han Xu, Zheng Hongwei, Song Chaofan, Zhou Lei, Wu Yan, Hong Bingyuan, Wen Kai
Fully automated controller for the real-flow calibration of natural gas flowmeters based

With the rapid development of the natural gas industry, the natural gas measurement handover volume is increasing year by year, and the calibration of natural gas flowmeter is becoming more and more important. This paper defines and demonstrates the framework of a fully automated controller for natural gas flowmeter calibration stations, from conceptualization to field test. When the calibrated flowmeter is installed on bench, the controller will identify the corresponding process by success tree algorithm. It checks whether the current process is appropriate, and automatically switch the best process according to the diameter of the calibrated meter. In the regulation stage of different calibrated flow rates, the controller performs predictive control on different flow rates according to the actual hydraulic condition by the calculation of hybrid driven model based on neural network model and mechanism model. This process gives the initial position of regulating valves with fast and efficient movement. Under a mild PID control law, the actual flow will go to the setting flow rates neither overshoot nor fall back. Finally, the control scheme is demonstrated in three original case studies, one in the simulation environment built by hydraulic simulation software, and the other two in real systems with different complexity. The algorithm is verified by simulation software and the control scheme is implemented in the actual environment. The results show that the intelligent calibration process based on model predictive control can increase the calibration efficiency. The integrated system based on hybrid driven can promote the intelligent development of natural gas calibration stations.

Wei Han, Can Li, Nan Sun, Chuanbo Zheng, Guanwen Huang, Chaofan Song, Chunhui Li
Capacity improvement of MT primary standard facility

MT primary standard facility is the highest standard of natural gas metering field in China. In order to improvethe capability level of the facility, the station took a series of measures. By adding a spherical tank insulation layer, changing the sampling position of the chromatograph and so on. After that, a new method was used to re-evaluate the uncertainty of the facility. At the same time, two nozzles were selected to carry out therepeatability and stability test, and the test results met the requirements of uncertainty. Afterall, the uncertaintylevel of the facility is increased from 0.1 % (k = 2) to 0.05 % (k = 2), and the uncertainty of the venturi nozzle outflow coefficient of calibration critical flow is 0.14 %. The capacity improvement work makes the level of the mt primary standard facility improved significantly, and it is very important for the valuation transfer and traceability system.

L. Cordova, I. Marfenko, A. Pfau, L. Shen
Considering Covariance in Reference Flowmeter-based Calibration Facilities

Given their simplicity, flow calibration facilities using flowmeters as reference standards are very common. The present paper introduces a method to estimate calibration facility uncertainty considering empirically determined correlation effects under working conditions. This improvement strongly increases the confidence in flowmeter-based calibration facilities of the particular type used, making third-party recognition of calibration services more reliable and transparent. A special type of calibration facility having multiple reference flowmeters installed both in-series and in-parallel, and fully automated scale calibration systems using weights was used. No human intervention is required for the calibration of the gravimetric system. When no covariance is considered, the expanded uncertainty of the facility can be expressed by the single flowmeter uncertainty reduced by the factor 1/m², m being the number of flowmeters used in parallel or in series; for two devices in n lines, by the factor 1/(2n)². This approach has its limitations and does not address possible unknown systematic effects during the calibration of each reference flowmeter. A more conservative approach assumes full correlation between the flowmeters used. The tested facility was designed to make covariance between two simultaneously calibrated reference devices measurable. By knowing the covariance, better understanding is given to the real performance of the reference flowmeters under working conditions and no full correlation needs to be assumed. In this paper we present firstly theoretical considerations and discuss the assumptions for modelling this particular type of facility. Secondly historical data is presented and analyzed, and finally, the facility performance of 0.03 % up to 100 kg/s is validated through flow comparisons using a highly accurate reference flowmeter.

Tao Meng, Lei Wang, Zhou Chang, Chao Xing,Huichao Shi
Method for direction diagnosis of multiple fluctuation sources on the flow standard facility

Extra uncertainty is introduced to the result of flowmeter calibration by flow fluctuations in the flow standard facility. Identifying sources of fluctuations is important for the location and elimination of the fluctuation sources in the flow standard facility, however it is difficult to diagnose the direction of fluctuation source when multiple sources exist. A correlation analysis method based on Empirical Mode Decomposition (EMD) utilizing the signals of pressure sensor and flowmeter is proposed to diagnose the directions of different fluctuation sources. The proposed method could separate the superposition signal of multiple fluctuation sources and effectively diagnose the directions of multiple fluctuation sources at one time and provide accurate information for the location and elimination of the fluctuation sources. Experiment platform was built based on a water flow standard facility and the direction diagnosis experiment of double fluctuation sources was conducted to verify the effectiveness of the proposed method. The experiment results shows that the directions of multiple fluctuation sources could be accurately diagnosed by the proposed method.

Chaojian Tao, Jiaodan Chen, Liqiong Huang, Shuqiang Chen, Shuxi Lin, Qiang Lin, Zeng Hong
Research on Temperature Control Technology of high- Pressure Loop Gas Flow Standard Facility

The high-pressure loop gas flow standard facility (hereinafter referred to as the facility) is a working measurement standard [1] for gas flowmeters to perform measurement performance tests under different pressures. It can study and improve the measurement performance of flowmeters under different pressures and different gas media, which is of great significance to the research of flow measurement technology. This paper studies the temperature control technology of the facility, the purpose is to make the temperature meet the working requirements of the facility and as close as possible to the existing international advanced level. Through theoretical analysis and experimental methods, combined with the author's company and the experience of external construction facilities, this paper designs an intelligent control system including its various subsystems, and realizes the design requirement that the temperature change of the facility's working gas is not greater than ± 0.1 °C/min. This paper shares the construction experience, and proposes a technical route for further improvement by using advanced control methods such as fuzzy control and neural network control to reach the existing international excellent level of ± 0.05 °C/min.

Wanli Yang, Xingen Wang, Yujie Chen, Yuming Shen
Research on Mathematical Model and Optimal Flow Characteristics of Steering Diverter

The function expression of the flow characteristics of rotary flow diverters was deduced. It can be seen from the expression that when the splitter plate of the diverter moves at a constant speed through the nozzle slot,the optimal flow characteristic curve with an approximately linear relationship is obtained. A flaw of the “Biryukov curves” was pointed out. It is also proposed that the essence of the flow diverter timing error Δt isthe error caused by the installation asymmetry and the flow characteristic asymmetry, not the travel difference. The tow computational equations of timing error were deduced, the equation in JJG 164-2000 (flowmeter method) and the one in ISO 4185 standard (static weighing method). A stepper motor drive system was designed, and experiments on the installation asymmetry of the diverter were carried out. The experimentalresults show that when the diverter splitter plate is triggered in advance, the timing error produces a negative deviation while lag trigger produces a positive deviation; and the greater the distance from the center point, the greater the absolute value of the timing error.

Page 13 of 912 Results 121 - 130 of 9113