Flow Velocity Estimation in Horizontal Oil Wells Using the Method of Thermal Flowmeter Based on the Fiber-Optic Distributed Permanent Monitoring System (Russian)

AbstractChanges in blood flow velocity play a crucial role during pathogenesis and progression of cardiovascular diseases. Imaging techniques capable of assessing flow velocities are clinically applied but are often not accurate, quantitative, and reliable enough to assess fine changes indicating the early onset of diseases and their conversion into a symptomatic stage. Magnetic particle imaging (MPI) promises to overcome these limitations. Existing MPI-based techniques perform velocity estimation on the reconstructed images, which restricts the measurable velocity range. Therefore, we developed a novel velocity quantification method by adapting the Doppler principle to MPI. Our method exploits the velocity-dependent frequency shift caused by a tracer motion-induced modulation of the emitted signal. The fundamental theory of our method is deduced and validated by simulations and measurements of moving phantoms. Overall, our method enables robust velocity quantification within milliseconds, with high accuracy, no radiation risk, no depth-dependency, and extended range compared to existing MPI-based velocity quantification techniques, highlighting the potential of our method as future medical application.

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On-Line Monitoring System for Monitoring SO2 in Fumes (1) — Monitoring Subsystem for SO2 Mass Concentration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.422.296 ◽

2011 ◽

Vol 422 ◽

pp. 296-299

Author(s):

Shi Long Wang ◽

Li Na Wang ◽

Hong Bo Wang ◽

Yong Hui Cai

Keyword(s):

Flow Velocity ◽

Monitoring System ◽

Flow Rate ◽

Mass Concentration ◽

National Monitoring ◽

Monitoring Result ◽

Short Period ◽

On Line ◽

Working Principle

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.

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Hybrid Scour Depth Prediction Equations for Reliable Design of Bridge Piers

Water ◽

10.3390/w13152019 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2019

Author(s):

Hossein Hamidifar ◽

Faezeh Zanganeh-Inaloo ◽

Iacopo Carnacina

Keyword(s):

Flow Velocity ◽

Critical Velocity ◽

Depth Estimation ◽

Hybrid Models ◽

Velocity Estimation ◽

Bridge Piers ◽

Critical Flow ◽

Scour Depth ◽

Critical Flow Velocity ◽

Estimation Equations

Numerous models have been proposed in the past to predict the maximum scour depth around bridge piers. These studies have all focused on the different parameters that could affect the maximum scour depth and the model accuracy. One of the main parameters individuated is the critical velocity of the approaching flow. The present study aimed at investigating the effect of different equations to determine the critical flow velocity on the accuracy of models for estimating the maximum scour depth around bridge piers. Here, 10 scour depth estimation equations, which include the critical flow velocity as one of the influencing parameters, and 8 critical velocity estimation equations were examined, for a total combination of 80 hybrid models. In addition, a sensitivity analysis of the selected scour depth equations to the critical velocity was investigated. The results of the selected models were compared with experimental data, and the best hybrid models were identified using statistical indicators. The accuracy of the best models, including YJAF-VRAD, YJAF-VARN, and YJAI-VRAD models, was also evaluated using field data available in the literature. Finally, correction factors were implied to the selected models to increase their accuracy in predicting the maximum scour depth.

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Study and Comparison of Vibration-Based Intrusive and Non-Intrusive Sand Monitoring System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.701.440 ◽

2013 ◽

Vol 701 ◽

pp. 440-444

Author(s):

Gang Liu ◽

Peng Tao Liu ◽

Bao Sheng He

Keyword(s):

Real Time ◽

Monitoring System ◽

Oil Production ◽

Oil Wells ◽

Oil Field ◽

Sand Production ◽

The Status

Sand production is a serious problem during the exploitation of oil wells, and people put forward the concept of limited sand to alleviate this problem. Oil production with limited sanding is an efficient mod of production. In order to complete limited sand exploitation, improve the productivity of oil wells, a real-time sand monitoring system is needed to monitor the status of wells production. Besides acoustic sand monitoring and erosion-based sand monitoring, a vibration-based sand monitoring system with two installing styles is proposed recently. The paper points out the relationships between sand monitoring signals collected under intrusive and non-intrusive installing styles and sanding parameters, which lays a good foundation for further study and actual sand monitoring in oil field.

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