Virtual Reference Model for Locating Two Leaks in a Pipeline

This work presents a case study that validates a software-based diagnosis system for automatically isolating two leaks in a main pipeline using only the flow rate and pressure data at the pipe ends for multiple operation points. The main features of the diagnosis procedure are the following: (1) the straightforward calculation to delimit the pipeline sections where the leaks are placed, (2) the multistage estimation of the positions and flow rate losses produced by the leaks without additional instrumentation, and (3) and the improvement in the service provided by network operators. By considering the invariability of the leak physical parameters and the relationships between the models for two leaks and a single leak located at lf, one establishes an array of equivalent equations for multiple operation points such that the solution of the array corresponds to the leak parameters. Thus, the numerical solution of the nonlinear equations’ array generates the unique leakage parameters. In particular, the nonlinear equations array is solved numerically by defining the error between the reference positions lf and the estimated equivalent positions using the gradient method. This novel procedure to identify the multiple leaks offers new alternatives for improving the monitoring of various leaks and is our paper’s main contribution. This paper’s case study is illustrated with simulated and experimental data from a 164 m long water pilot pipeline, which achieves relative errors below 7%.