Method for Monitoring Average Flow Velocity of Fumes by Mean of Velocity Field Constant

2012 ◽  
Vol 170-173 ◽  
pp. 2609-2612
Author(s):  
Li Na Wang ◽  
Yong Hui Cai ◽  
Hong Bo Wang ◽  
Shi Long Wang

In order to achieve the target of controlling SO2 emissions in fumes in a short period of time in China, it is necessary to develop a SO2 on-line monitoring system (CEMS) that is suitable for China. To monitor total emissions of SO2 in fumes, the concentration of SO2 in the fumes and fumes flow rate must be monitored simultaneously. To monitor fumes flow rate, first we must monitor its average flow velocity, this is a major technical problem need to solve in the SO2 CEMS. By means of study on velocity field constant in flue, An advanced method for monitoring average flow velocity of fume by mean of velocity field constant is presented, meanwhile an innovative device has been developed to detect velocity field constants automatically, which has resolved the technical difficulty in automated monitoring of fume average velocity in the flue. Through experiment and testing, the monitoring method researched is correct, structure of detecting device is reasonable, its monitoring results are stable and reliable.

2011 ◽  
Vol 422 ◽  
pp. 233-237
Author(s):  
Shi Long Wang ◽  
Li Na Wang ◽  
Yong Hui Cai ◽  
Hong Bo Wang

A SO2 on-line monitoring system (CEMS) has been developed by the author based on the principle of electrochemistry. This system consists of SO2 mass concentration monitoring subsystem (the subsystem had been described in on-line system for monitoring SO2 in fumes(1)) and SO2 flow velocity and flow rate monitoring subsystem. In the paper, the working principle and procedure of SO2 flow velocity and flow rate monitoring subsystem are described in detail. In the meantime, an advanced method for measuring average flow velocity of fumes by mean of “velocity field constant” is presented. A innovative device has been developed to detect velocity field constants automatically, which has resolved the technical difficulty in automated monitoring of fumes average velocity in the flue.


2011 ◽  
Vol 422 ◽  
pp. 296-299
Author(s):  
Shi Long Wang ◽  
Li Na Wang ◽  
Hong Bo Wang ◽  
Yong Hui Cai

In order to achieve the target of controlling SO2 emissions in fumes in a short period of time in China, a SO2 on-line monitoring system (CEMS) has been developed by the authorased on the principle of electrochemistry. This system consists of two subsystems: (1) SO2 mass concentration monitoring and (2) SO2 flow velocity and flow rate monitoring. In the paper, the procedure of system and working principle and method of SO2 mass concentration monitoring subsystem are described in detail (SO2 flow velocity and flow rate monitoring subsystem is described by another paper).Two subsystems work synchronously to monitor and calculate the SO2 emissions, then the on-line monitoring of SO2 emissions is achieved. Through experiment and testing, monitoring result of the system is stable and reliable, which has reached the national monitoring standards and passed the appraisal.


Author(s):  
С.А. Исаев ◽  
А.Б Мазо ◽  
Д.В. Никущенко ◽  
И.А. Попов ◽  
А.Г. Судаков

The slope of the oval-trench dimple in the corridor package on the hydrodynamic stabilized section of the narrow channel has a dramatic effect on the anomalous intensification of returned and swirling flows in the dimple, leading to a 3–4-fold decrease in relative negative friction in the range of angles from 40° to 60°, an increase in the highest speed return and secondary flows up to 0.8 and 1.18 with respect to the mass-average flow velocity in the channel.


2019 ◽  
Vol 82 (1) ◽  
Author(s):  
Khairul Amri ◽  
Suprijanto Suprijanto ◽  
Deddy Kurniadi ◽  
Endang Juliastuti

A conventional transit time ultrasonic flowmeter (USM) has a high accuracy for symmetric flow profiles but inaccurate for asymmetric flow profiles. Flow profile shapes can also change over time and difficult to predict. USM with tomographic configuration (USM-Tomo) can adapt to the flow profile changes but result in low temporal resolution. Meanwhile, USM with an adaptive weighting method can measure asymmetric flow velocity but limited to specific asymmetric flow profiles. An alternative scheme to determine adaptive weighting in various asymmetric flow profiles, we proposed a hybrid USM-Tomo. This scheme proposes programmable acoustic path configuration that could set the path mode between USM and tomography. Reducing computation of time of flight in each acoustic can be done by applying the dual-transducers technique. An adaptive weighting of hybrid USM-Tomo is calculated based on the mapping function between the set of velocity on 6 parallel paths of USM and average flow velocity from USM-Tomo. The mapping function is determined using machine learning, i.e., Artificial Neural Network (ANN) and Support Vector Regression (SVR). In the measurement phase, the average flow velocity is determined using the mapping function with input 6 parallel acoustic paths.  Based on various types of asymmetric flow profiles used in the experiment, the 6 parallel acoustic paths of USM could produce average flow velocity with error below 1% compared to USM-Tomo. Therefore, the proposed hybrid USM-Tomo scheme has potential to be an alternative scheme for flow meter in industrial application.


2012 ◽  
Vol 3 ◽  
pp. 163-171 ◽  
Author(s):  
Mojca Vilfan ◽  
Gašper Kokot ◽  
Andrej Vilfan ◽  
Natan Osterman ◽  
Blaž Kavčič ◽  
...  

Biological cilia are found on surfaces of some microorganisms and on surfaces of many eukaryotic cells where they interact with the surrounding fluid. The periodic beating of the cilia is asymmetric, resulting in directed swimming of unicellular organisms or in generation of a fluid flow above a ciliated surface in multicellular ones. Following the biological example, externally driven artificial cilia have recently been successfully implemented as micropumps and mixers. However, biomimetic systems are useful not only in microfluidic applications, but can also serve as model systems for the study of fundamental hydrodynamic phenomena in biological samples. To gain insight into the basic principles governing propulsion and fluid pumping on a micron level, we investigated hydrodynamics around one beating artificial cilium. The cilium was composed of superparamagnetic particles and driven along a tilted cone by a varying external magnetic field. Nonmagnetic tracer particles were used for monitoring the fluid flow generated by the cilium. The average flow velocity in the pumping direction was obtained as a function of different parameters, such as the rotation frequency, the asymmetry of the beat pattern, and the cilium length. We also calculated the velocity field around the beating cilium by using the analytical far-field expansion. The measured average flow velocity and the theoretical prediction show an excellent agreement.


Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4786 ◽  
Author(s):  
Lei Kang ◽  
Andrew Feeney ◽  
Riliang Su ◽  
David Lines ◽  
Sivaram Nishal Ramadas ◽  
...  

Accurate average flow velocity determination is essential for flow measurement in many industries, including automotive, chemical, and oil and gas. The ultrasonic transit-time method is common for average flow velocity measurement, but current limitations restrict measurement accuracy, including fluid dynamic effects from unavoidable phenomena such as turbulence, swirls or vortices, and systematic flow meter errors in calibration or configuration. A new spatial averaging method is proposed, based on flexural ultrasonic array transducer technology, to improve measurement accuracy and reduce the uncertainty of the measurement results. A novel two-dimensional flexural ultrasonic array transducer is developed to validate this measurement method, comprising eight individual elements, each forming distinct paths to a single ultrasonic transducer. These paths are distributed in two chordal planes, symmetric and adjacent to a diametral plane. It is demonstrated that the root-mean-square deviation of the average flow velocity, computed using the spatial averaging method with the array transducer is 2.94%, which is lower compared to that of the individual paths ranging from 3.65% to 8.87% with an average of 6.90%. This is advantageous for improving the accuracy and reducing the uncertainty of classical single-path ultrasonic flow meters, and also for conventional multi-path ultrasonic flow meters through the measurement via each flow plane with reduced uncertainty. This research will drive new developments in ultrasonic flow measurement in a wide range of industrial applications.


2002 ◽  
Vol 34 ◽  
pp. 385-390 ◽  
Author(s):  
Masamu Aniya ◽  
Renji Naruse ◽  
Satoru Yamaguchi

AbstractUsing vertical aerial photographs taken manually with a 6 × 6 cm format camera in 1984, 1986 and 1999, the surface morphology of the ablation area of Glaciar Soler, Hielo Patagónico Norte (northern Patagonia icefield), Chile, was studied. Glaciar Soler has an area of 50.9 km2; the ablation area below the icefall is about 7 km long and 2 km wide. An uncontrolled aerial-photographic mosaic for the area below the icefall was assembled from 40–60 aerial photographs, on which the surface morphology was mapped from interpretation of stereo pairs of the enlarged photographs (scales of 1:4500 to 1: 8000). Themapped features include debris-free and debris-covered ices, ogive bands and waves, crevasses, supraglacial streams, moulins, medial moraines, troughs and grooves. A total of 32–34 pairs of ogive bands were recognized, from which an average flow velocity of about 160 m a–1 was deduced. The spacing of a pair of light and dark ogive bands indicates that the flow velocity ranges from about 350 ma–1 near the icefall to some 100 ma–1 near the snout. Comparison of the field-measured data with the ogive spacing indicates that the seasonal variation in flow velocity of Glaciar Soler is very large, probably because of variation in the amount of basal sliding.


2014 ◽  
Vol 955-959 ◽  
pp. 3385-3388
Author(s):  
Si Jia Chen ◽  
Yu Shao ◽  
Liang Tao ◽  
Ying Ying Zhao ◽  
Han Feng Jing ◽  
...  

The leak detecting-ball moving in pipes combined the sensors of the acoustic leak detection achieves the high responsiveness to small leaks of the water distribution system (WDS). The dynamic characteristics of the single sphere moving inside pressure pipes are studied for optimal design of the leak detecting-ball. The experimental balls having different densities are made of three types of material by using 3D printing, including tetrafluoroethylene (ETFE), photosensitive resin (PR) and wax. The balls have densities from 1.06 to 1.35 and different diameters, ball-to-pipe diameter ratios from 0.32 to 0.5. The Reynolds numbers of the pipe flows are from 1400 to 50000. The moving velocity of the balls with different pipe flow velocities, ball densities, and ball-to-pipe diameter ratios are investigated through the laboratory experiments. The velocities of balls in some of the experimental tests are greater than the average flow velocity. These larger balls rolled faster than the average flow velocity because of the maximum thrust by the pressure flow in the center of the circular tube section.


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