CCWi2017: F90 'Pipe Leak Diagnostic using Empirical Mode Decomposition (EMD) and Automatic Selection of the Intrinsic Mode Function (IMF)'

In a recent study, the analysis of pressure transient signals could be seen as an accurate and low- cost method for leak and feature detection in water distribution systems. Transient phenomena occur due to sudden changes in the fluid’s propagation in pipelines system caused by rapid pressure and flow fluctuation due to events such as closing and opening valves rapidly or through pump failure. In this paper, it is to apply the Hilbert-Huang transform (HHT) as a method to analyse the pressure transient signal. The HHT is a way to decompose a signal into intrinsic mode functions (IMF). However, this method has the difficulty in selecting the suitable IMF for the next data post-processing method which is Hilbert Transform (HT). The current paper presents the implementation of an integrated kurtosis-based algorithm for a z-filter technique (I-kaz) to kurtosis ratio (I-kaz-Kurtosis), for this allows automatic selection of the IMF that should be used. This technique is demonstrated on a 57.90-meter medium high-density polyethylene (MDPE) pipe installed with a single artificial leak. The analysis results using the I-kaz-kurtosis ratio revealed that the method can be used as an automatic selection of the IMF although the noise level ratio of the signal is lower. Despite this, the I-kaz-kurtosis ratio method is recommended as a means to implement an automatic selection technique of the IMF for HHT analysis.