A Dual Model for Leak Detection and Localization

In this work, we employ a hierarchical approach for leak diagnosis, where time series analysis of AMR data, demand models and measured flows is first used for demand calibration. In the next step, efficient mathematical optimisation is used to calibrate the pipe roughnesses and valve statuses and update the network data. Finally, the calibrated water network model is employed to first build a dual hydraulic network representation for the combined sensor & water systems, simulation of which provide a first estimate for the leak’s size and location. This dual network is then used to (i) detect the start time of the leaks as well as (ii) to compute analytical sensitivities and the Pearson correlation for pressure residuals, which allow further localisation of leaks. This whole process of leak diagnosis and localisation scales well as the dual network size is of the same order as the original network, analytical derivations are used for computing sensitivities, and a fast and stable least squares method is used for calibration and valve status assessment.