A Leak Localization Method of Pipeline by Means of Fluid Transient Model

1993 ◽  
Vol 115 (3) ◽  
pp. 162-167 ◽  
Author(s):  
T. Kiuchi
Keyword(s):  
Flow Rate ◽  
Transient Condition ◽  
Accurate Estimation ◽  
Pipeline System ◽  
Transient Model ◽  
Pressure Profiles ◽  
Fluid Transient ◽  
Abrupt Changes ◽  
Conventional Methods ◽  
Rate Profile

This paper describes a method for estimating the position of a detected leak by applying a fluid transient model to a real-time pipeline system. The method takes into account flow rate and pressure profiles along a pipeline in a transient condition based on an assumption of quasi-steady-state flow. The result of case studies using a hypothetical gas pipeline system shows that, even in a transient condition, the method gives a more accurate estimation of a leak position than conventional methods which do not consider flow rate or pressure profiles along a pipeline. The method is also applicable to a pipeline having consumer stations which cause abrupt changes of flow rate profile along the pipeline. Furthermore, the influence of instrument accuracy on the result of the method is examined. The result also shows the advantage of the method compared to the conventional methods.

scholarly journals Correction to Flow Rate Profile Interpretation for a Two-Phase Flow in Multistage Fractured Horizontal Wells by Inversion of DTS Data

ACS Omega ◽  
2020 ◽  
Vol 5 (41) ◽  
pp. 26955-26955
Author(s):  
Hongwen Luo ◽  
Beibei Jiang ◽  
Haitao Li ◽  
Ying Li ◽  
Zhangxin Chen
Keyword(s):  
Flow Rate ◽  
Two Phase Flow ◽  
Horizontal Wells ◽  
Phase Flow ◽  
Two Phase ◽  
Fractured Horizontal Wells ◽  
Rate Profile

scholarly journals Analytic wavelet packets for robust ultrasonic flow measurement

2020 ◽  
Vol 87 (1) ◽  
pp. 45-54
Author(s):  
Matthias Bächle ◽  
Daniel Alexander Schwär ◽  
Fernando Puente León
Keyword(s):  
Transit Time ◽  
Flow Measurement ◽  
Principal Component ◽  
Time Difference ◽  
Frequency Resolution ◽  
Wavelet Packets ◽  
Accurate Estimation ◽  
Time Frequency ◽  
Analytic Wavelet ◽  
Conventional Methods

AbstractA key element in robust transit-time ultrasonic flow measurement is the accurate estimation of the transit-time difference. Conventional methods, such as cross-correlation or the estimation in the phase domain, are limited in their robustness against signal distortions, interfering signals or noise. In this work, we present a novel method to estimate the transit-time difference through the fusion of selected analytic wavelet packet coefficients. The combination of the complex coefficients, which represent a projection of the signal on analytic wavelets, with a configurable time-frequency resolution allows a sub-sample estimation at the frequency of interest. After giving an introduction into the fundamentals of analytic wavelet packets based on multi-scale filtering, we introduce two features that correlate strongly with the transit-time difference. The selection and fusion of these features is done by using correlation coefficients with a calibration set and principal component analysis. Finally, using a clamp-on flow measurement system, the robustness against temperature variation and measurement noise is shown and compared with conventional methods.

Low-cost flow-rate estimate in separate layers along gas wells from temperature and pressure profiles

2013 ◽  
Vol 53 (1) ◽  
pp. 285
Author(s):  
Emile Barrett ◽  
Imran Abbasy ◽  
Chii-Rong Wu ◽  
Zhenjiang You ◽  
Pavel Bedrikovetsky
Keyword(s):  
Thermal Conductivity ◽  
Mathematical Model ◽  
Flow Rate ◽  
Low Cost ◽  
Pressure Sensors ◽  
Gas Wells ◽  
Production Rates ◽  
Pressure Profiles ◽  
Temperature And Pressure ◽  
The Mathematical Model

Estimation of rate profile along the well is important information for reservoir characterisation since it allows distinction of the production rates from different layers. The temperature and pressure sensors in a well are small and inexpensive; while flow meters are cumbersome and expensive, and affect the flow in the well. The method presented in this peer-reviewed paper shows its significance in predicting the gas rate from temperature and pressure data. A mathematical model for pressure and temperature distributions along a gas well has been developed. Temperature and pressure profiles from nine well intervals in field A (Cooper Basin, Australia) have been matched with the mathematical model to determine the flow rates from different layers in the well. The presented model considers the variables as functions of thermal properties at each location, which is more accurate and robust than previous methods. The results of tuning the mathematical model to the field data show good agreement with the model prediction. Simple and robust explicit formulae are derived for the effective estimation of flow rate and thermal conductivity in gas wells. The proposed approach has been applied to determine the well gas rate and formation thermal conductivity from the acquired well pressure and temperature data in field A. It allows for recommending well stimulation of layers with low production rates.

scholarly journals 1D-3D coupling investigation of hydraulic transient for power-supply failure of centrifugal pump-pipe system

2019 ◽  
Vol 21 (5) ◽  
pp. 708-726 ◽  
Author(s):  
Xiaoqin Li ◽  
Xuelin Tang ◽  
Min Zhu ◽  
Xiaoyan Shi
Keyword(s):  
Turbulent Flows ◽  
Flow Rate ◽  
Power Supply ◽  
Nuclear Power ◽  
Transient Flow ◽  
Internal Flow ◽  
Transition Process ◽  
Pipeline System ◽  
Pipe System ◽  
Rotating Speed

Abstract In the pumping station, the main feedwater system and the reactor system of nuclear power plant, power-supply failure causes strong hydraulic transients. One-dimensional method of characteristics (1D-MOC) is used to calculate the transient process in the pipeline system while three-dimensional (3D) computational fluid dynamics is employed to analyze the turbulent flows inside the pump and to obtain the performance parameters of the pump, and the data exchanges on the boundary conditions of the shared interface between 1D and 3D domains are updated based on the MpCCI platform. Based on the equation of motion of the pump motion parts, the relationship between the external characteristics and the internal flow field in the pump is further investigated because the dynamic behavior of the pump and the detailed fluid field evolutions inside the pump are captured during the transition process, and the transient flow rate, rotating speed, and pressure inside the impeller are comprehensively investigated. Meanwhile, compared with the data gained by experiment and traditional 1D-MOC, the relative errors of rotating speed and the flow rate obtained by 1D-3D coupling method are smaller than those by 1D-MOC. Furthermore, the influences of the main coupling parameters and coupling modes on the calculation results are analyzed, and the cause of the deviation is further explained.

scholarly journals Hydraulic Engineering at 100 BC-AD 300 Nabataean Petra (Jordan)

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3498
Author(s):  
Charles R. Ortloff
Keyword(s):  
Water Supply ◽  
Flow Rate ◽  
Distribution Systems ◽  
Maximum Flow ◽  
Hydraulic Engineering ◽  
World Heritage Site ◽  
Maximum Flow Rate ◽  
Pipeline System ◽  
Supply And Distribution ◽  
Pipeline Systems

The principal water supply and distribution systems of the World Heritage site of Petra in Jordan were analyzed to bring forward water engineering details not previously known in the archaeological literature. The three main water supply pipeline systems sourced by springs and reservoirs (the Siq, Ain Braq, and Wadi Mataha pipeline systems) were analyzed for their different pipeline design philosophies that reflect different geophysical landscape challenges to provide water supplies to different parts of urban Petra. The Siq pipeline system’s unique technical design reflects use of partial flow in consecutives sections of the main pipeline to support partial critical flow in each section that reduce pipeline leakage and produce the maximum flow rate the Siq pipeline can transport. An Ain Braq pipeline branch demonstrated a new hydraulic engineering discovery not previously reported in the literature in the form of an offshoot pipeline segment leading to a water collection basin adjacent to and connected to the main water supply line. This design eliminates upstream water surges arising from downstream flow instabilities in the two steep pipelines leading to a residential sector of Petra. The Wadi Mataha pipeline system is constructed at the critical angle to support the maximum flow rate from a reservoir. The analyses presented for these water supply and distribution systems brought forward aspects of the Petra urban water supply system not previously known, revising our understanding of Nabataean water engineers’ engineering knowledge.

Flow Rate Measurement Method and Apparatus of Thick Pastes

2012 ◽  
Vol 605-607 ◽  
pp. 945-950 ◽  
Author(s):  
Shuang Yu Zhang ◽  
Zhi Nan Wang ◽  
Xue Di Hao ◽  
Miao Wu
Keyword(s):  
Flow Rate ◽  
Electromagnetic Induction ◽  
Experimental Error ◽  
Measurement Method ◽  
Pipeline System ◽  
Rate Measurement ◽  
Flow Rate Measurement ◽  
Capacity Calculation ◽  
Selection For ◽  
Coal Slime

Research on the rheological characteristics and delivery resistance needs precise flow rate in pipes of thick pastes which is the basis of delivery capacity calculation and equipment selection for a pipeline system. However, the existing apparatuses are not suitable for flow rate measurement of the thick pastes, so it is necessary to design a kind of apparatus applicable to the above requirements. This paper by using an electromagnetic induction coil as a sensor, designs a kind of flow rate measurement apparatus of thick pastes. It describes the measurement method and its principle, and analyzes the error of this apparatus. A loop-pipe transportation test of coal slime was conducted, and it shows the relative test experimental error of this apparatus is less than 1%.

Server-Rack Air Flow and Heat Transfer Interactions in Data Centers

2007 ◽  
Author(s):  
S. P. Tan ◽  
K. C. Toh ◽  
Y. W. Wong
Keyword(s):  
Heat Transfer ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Data Center ◽  
Vertical Plane ◽  
Pressure Profile ◽  
Design Data ◽  
Flow And Heat Transfer ◽  
Pressure Profiles

The current study focuses on modeling the server-rack airflow and heat transfer interaction in a data center. In a typical computing facility, the computing requirements are often gradually built-up. For example, in this instance, two servers are placed in a rack designed for a six-server stack. Each server will be separately modeled to the required specifications, and also so that their numbers and placement can be changed. The mass flow rate through the server is determined by examining how pressure profiles develop at the inlet and outlet. This mass flow rate then becomes the input into the rack model. The air inflow temperatures at the front and rear grills were obtained from experiments. The pressure profile into and out of the servers were extracted from the rack model and substituted back into the server model. Iteration continues till an acceptable level of convergence is obtained. To validate the models, experiments were carried out using thermocouples arranged in a 3 × 3 grid on a vertical plane between the exit of the server and the rear cabinet wall of the rack. The results showed that the modeling had captured the essence of the flow and heat transfer interaction. The temperature and pressure profile at the rack inlet and outlet, although in a segmented form, have performed adequately to obtain a good approximation of the flow and temperature distribution within the server/rack. The methodology of passing parameters at the server-rack level using a segmented pressure profile has been established. A similar rack-room level interaction will subsequently be developed. In essence, the methodology is equivalent to replacing the server in the rack and the rack in the room with combined flow network - thermal models. But because of the coupled nature of these two different length scale systems, the models are obtained through an iterative process. The approach enables various combinations of servers and racks to be studied quickly for any undesirable effects of off-design data center operation or layout.

A 3D Transient Model for the Multiphase Flow in a Progressing-Cavity Pump

SPE Journal ◽  
2016 ◽  
Vol 21 (04) ◽  
pp. 1458-1469 ◽  
Author(s):  
Victor W. de Azevedo ◽  
João A. de Lima ◽  
Emilio E. Paladino
Keyword(s):  
Multiphase Flow ◽  
Flow Rate ◽  
Homogeneous Model ◽  
Volumetric Flow Rate ◽  
Volumetric Efficiency ◽  
Two Phase ◽  
Transient Model ◽  
Viscous Losses ◽  
Constant Displacement ◽  
Gas Volume

Summary This paper presents the development of a computational-fluid-dynamics (CFD) model for the 3D transient two-phase flow within a progressing-cavity pump (PCP). The model implementation was only possible because of the meticulous mesh-generation and mesh-motion algorithm, previously published by the authors, which is briefly described herein. In this algorithm, a structured mesh was generated by defining all nodes’ positions and connectivities, for each rotor position by means of FORTRAN subroutines, which were embodied into ANSYS CFX software. The model is capable of predicting accurately the volumetric efficiency and the viscous losses, and it provides detailed information of pressure and velocity fields and void distribution along the pump. Such information could be of fundamental importance for product development and/or optimization for field operation. In field applications, the common situation is that in which the oil comes into the pump accompanied with free gas, which characterizes a multiphase flow. Simplified models on the basis of the calculation of the backflow or “slippage,” which is subtracted from the displaced flow rate, fail to characterize the PCP performance under multiphase conditions because the slip is variable along the pump. In this model, the governing equations were solved with an element-based finite-volume method in a moving mesh. The Eulerian-Eulerian approach, considering the homogeneous model, is used to model the flow of the gas/liquid mixture. The compressibility of the gas is taken into account, which is one of the main shortcomings in positive/constant displacement pumps. The effects of the different gas-volume fractions (GVFs) in pump volumetric efficiency, pressure distribution, power, slippage flow rate, and volumetric flow rate were analyzed, and some new insights are presented about the slippage in PCPs operating in multiphase conditions. The results show that the developed model is capable of reproducing pump dynamic behavior under multiphase-flow conditions performed early in experimental works.

MP13-17 A MODEL FOR PREDICTING THE FLOW RATE PROFILE OF A VOIDING PATIENT USING URINE ACOUSTICS - MAKING PROGRESS TOWARDS REMOTE FOLLOW UP FOR URETHROPLASTY

2014 ◽  
Vol 191 (4S) ◽  
Author(s):  
Sean McAdams ◽  
Fluvio Lobo ◽  
Carly Aho ◽  
Joseph Mein ◽  
Linden Vander-Linden ◽  
...  
Keyword(s):  
Flow Rate ◽  
Rate Profile
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