Analysis of the smallest detectable leakage flow rate of negative pressure wave-based leak detection systems for liquid pipelines

2008 ◽  
Vol 32 (8) ◽  
pp. 1669-1680 ◽  
Author(s):  
Chuanhu Ge ◽  
Guizeng Wang ◽  
Hao Ye
Keyword(s):  
Flow Rate ◽  
Negative Pressure ◽  
Pressure Wave ◽  
Leak Detection ◽  
Leakage Flow ◽  
Detection Systems ◽  
Leakage Flow Rate ◽  
Negative Pressure Wave

Pipeline Leak Detection Based on Double Sensor Negative Pressure Wave

2013 ◽  
Vol 313-314 ◽  
pp. 1225-1228 ◽  
Author(s):  
Chun Xia Hou ◽  
Er Hua Zhang
Keyword(s):  
False Alarm ◽  
Negative Pressure ◽  
Pressure Wave ◽  
Detection System ◽  
Low Frequency ◽  
Leak Detection ◽  
Frequency Component ◽  
Economic Losses ◽  
Single Sensor ◽  
Negative Pressure Wave

Pipeline leak lead to huge economic losses and environmental pollution. Leak detection system based on single sensor negative pressure wave often causes false alarm. In this paper the double sensor method is adopted to exclude false alarm by determining the propagation direction of the pressure wave. In order to remove the inverse coherent interference caused by pump running, the phase difference of primary low frequency component is used to identify the sign of the time delay between the double sensors. The experiment shows the mothod is effective.

Research of Heating Oil Pipeline Leak Detection Based on Negative Pressure Wave

ICPTT 2012 ◽  
2012 ◽  
Author(s):  
Chi Chen ◽  
Huijun Zhao ◽  
Xiaobin Wang ◽  
Ning Zhou ◽  
Shuli Wang
Keyword(s):  
Negative Pressure ◽  
Pressure Wave ◽  
Leak Detection ◽  
Oil Pipeline ◽  
Heating Oil ◽  
Negative Pressure Wave

Synergy in Leak Detection: Combining Leak Detection Technologies That Use Different Physical Principles

2014 ◽  
Author(s):  
Peter Y. Han ◽  
Mark S. Kim
Keyword(s):  
Negative Pressure ◽  
Pressure Wave ◽  
Leak Detection ◽  
Wave System ◽  
Oil Pipeline ◽  
Balance System ◽  
Volume Balance ◽  
Product Withdrawal ◽  
Negative Pressure Wave ◽  
Detection Technologies

Different leak detection technologies offer different benefits and limitations. Popular options include real-time transient models, statistical volume balance analysis and negative pressure wave systems. Atmos offers a combination of different systems to improve the leak detection performance on a pipeline. This paper outlines the very successful integration of a Statistical Volume Balance System and a Negative Pressure Wave System on a crude oil pipeline. The live product withdrawal tests demonstrated that the combined system maximized the reliability, detection speed, location accuracy and sensitivity of the overall leak detection system. This paper will examine the benefits and technical challenges of combining these two leak detection technologies. The integrated solution delivers the reliability and robustness of the Statistical Volume Balance System together with the rapid response time and location accuracy of the Negative Pressure Wave System. The field application of the two systems integrated on a 170 kilometer crude oil pipeline will be explained in detail, along with the results of some actual controlled product withdrawal tests on the pipeline.

scholarly journals Impact of Orifice-to-Pipe Diameter Ratio on Leakage Flow: An Experimental Study

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2189
Author(s):  
Tingchao Yu ◽  
Xiangqiu Zhang ◽  
Iran E. Lima Neto ◽  
Tuqiao Zhang ◽  
Yu Shao ◽  
...  
Keyword(s):  
Experimental Study ◽  
Flow Rate ◽  
Pipe Wall ◽  
Pressure Head ◽  
Diameter Ratio ◽  
Pipe Diameter ◽  
Leakage Flow ◽  
Leakage Flow Rate ◽  
Different Shapes ◽  
Real Scale

The traditional orifice discharge formula used to estimate the flow rate through a leak opening at a pipe wall often produces inaccurate results. This paper reports an original experimental study in which the influence of orifice-to-pipe diameter ratio on leakage flow rate was investigated for several internal/external flow conditions and orifice holes with different shapes. The results revealed that orifice-to-pipe diameter ratio (or pipe wall curvature) indeed influenced the leakage flow, with the discharge coefficient ( C d ) presenting a wide variation (0.60–0.85). As the orifice-to-pipe diameter ratio decreased, the values of C d systematically decreased from about 12% to 3%. Overall, the values of C d also decreased with β (ratio of pressure head differential at the orifice to wall thickness), as observed in previous studies. On the other hand, orifice shape, main pipe flow velocity, and external medium (water or air) all had a secondary effect on C d . The results obtained in the present study not only demonstrated that orifice-to-pipe diameter ratio affects the outflow, but also that real scale pipes may exhibit a relevant deviation of C d from the classical range (0.61–0.67) reported in the literature.

scholarly journals Effect of hydraulic and geometric factors upon leakage flow rate in pressurized pipes

RBRH ◽  
2021 ◽  
Vol 26 ◽  
Author(s):  
Mayara Francisca da Silva ◽  
Fábio Veríssimo Gonçalves ◽  
Johannes Gérson Janzen
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Flow Rate ◽  
Leakage Flow ◽  
Cfd Simulations ◽  
Mean Velocity ◽  
Leakage Flow Rate ◽  
Geometric Factors ◽  
Leakage Area ◽  
Computational Fluid Dynamics Cfd

ABSTRACT Computational Fluid Dynamics (CFD) simulations of a leakage in a pressurized pipe were undertaken to determine the empirical effects of hydraulic and geometric factors on the leakage flow rate. The results showed that pressure, leakage area and leakage form, influenced the leakage flow rate significantly, while pipe thickness and mean velocity did not influence the leakage flow rate. With relation to the interactions, the effect of pressure upon leakage flow rate depends on leakage area, being stronger for great leakage areas; the effects of leakage area and pressure on leakage flow rate is more pronounced for longitudinal leakages than for circular leakages. Finally, our results suggest that the equations that predict leakage flow rate in pressurized pipes may need a revision.

scholarly journals Leakage Characteristic Identification of Labyrinth Seals on Reciprocating Piston through Transient Simulations

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Lingzi Wang ◽  
Jianmei Feng ◽  
Mingfeng Wang ◽  
Zenghui Ma ◽  
Xueyuan Peng
Keyword(s):  
Flow Rate ◽  
Pressure Ratio ◽  
Piston Compressor ◽  
Pressure Change ◽  
Labyrinth Seal ◽  
Relative Molecular Mass ◽  
Geometrical Parameters ◽  
Leakage Flow ◽  
Reciprocating Motion ◽  
Leakage Flow Rate

In the reciprocating labyrinth piston compressor, the characteristic of the internal leakage is crucial for the leakage management and performance improvement of the compressor. However, most of the published studies investigated the rotor-stator system, and those who study the reciprocating piston-cylinder system basically focus on the effects of the geometrical parameters. These conclusions could not directly be applied to predict the real-time leakage flow rate through the labyrinth seal because of the fast reciprocating motion of the piston, which will cause continually pressure change in two compression chambers, and then the pressure fluctuation will affect the flow through the labyrinth seal. A transient simulation model employing the multiscale dynamic mesh, which considers the effect of the reciprocating motion of the piston in the cylinder, is established to identify the characteristics of the internal leakage. This model was verified by a specially designed compressor, and the influence of various parameters was analyzed in detail. The sealing performance decreased linearly with the increase in the pressure ratio, and higher pressure inlet leads to higher leakage flow under the same pressure ratio. The labyrinth seal performance positively correlated to the increase of the rotational speed. Leakage characteristics of five working mediums were carried out, and the results indicated that the relative leakage decreased with an increase in the relative molecular mass. From this study, the realistic internal leakage flow rate under different operating parameters in the reciprocating labyrinth piston compressor could be predicated.

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