Sensitivity analysis of a transient-based frequency domain method for extended blockage detection in water pipeline systems

Partial blockages are commonly formed in water supply pipelines due to many factors, such as deposition, biofilm, and corrosion in the natural water supply process, as well as valve throttle in the artificial construction and operation process, which may cause additional energy losses and serious water supply accidents in the system. Recently, a transient-based frequency domain method (TBFDM) has been developed by the author for extended partial blockage detection, and it was found to be efficient, nonintrusive, and inexpensive to apply. While this method has been validated and applied for numerical and laboratory experiments in previous studies for a variety of blockage and hydraulic conditions, the application results revealed that the accuracy of the TBFDM may be easily affected by uncertainties in the experimental process. This paper investigates the sensitivity of the developed TBFDM to different uncertainty factors that commonly exist in water pipeline systems, with perspective to better understand and use this efficient and economic method in practice. The methods of firstorder second-moment analysis and Monte Carlo simulation are adopted in this paper for the investigation. The obtained results are discussed for the validity range and limitations of current TBFDM for practical applications.