Investigation into the Effects of Real-world Uncertainties on A Computer Model-based Leak Detection System for Liquid Pipelines

  • Author / Creator
    Lu, Zhe
  • Leaks in oil pipeline systems can significantly affect the environment and lead to economic losses. Pipeline companies are working to improve existing methods to monitor their pipelines more effectively. Computer model-based leak detection methods detect leaks by analyzing the pipeline hydraulic state and have been commonly employed in the energy pipeline industry. However, the effectiveness of these types of leak detection systems is often challenged by real-world uncertainties. This study quantitatively evaluated the impacts of uncertainties on leak detectability of a widely used real-time transient model based leak detection system. Uncertainties in fluid properties, data acquisition systems, and field sensors were assessed. Errors were introduced into the identified uncertainty sources one at a time and then randomly; and the changes in leak detection time caused by the real-world uncertainties were quantified using simulated leaks. This study provides valuable quantitative results contributing towards a better understanding of how real-world uncertainties may affect leak detection. A general ranking of the importance of the uncertainty sources was obtained; ordered from high to low, they are time skew, bulk modulus error, viscosity error, and polling time. It was also shown that inertia-dominated systems with low R factors were less sensitive to uncertainties compared to friction-dominated systems with high R factors.

  • Subjects / Keywords
  • Graduation date
    Fall 2017
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.