PRESSURE WAVE BEHAVIOR AND LEAK DETECTION IN PIPELINES

In the present work on-line computational techniques have been develop ed and used in the analysis of hydraulic transients caused by leakage, in order to detect and locate pipeline ruptures. Pressure transients were obtained in two PVC pipelines 3/4'' diameter by using four pressu re transducers connected to a PC computer equipped with A/D and DIA co nverters. The pipelines were 433 m and 1,248 m long. Leaks were simula ted at different positions along the pipelines. Experiments were carri ed out for different liquid flow rates corresponding to Reynolds numbe r in the range from 2,000 to 13,000. Leak percentage were in the range from 5% to 50% of the nominal liquid flow. A computer program to be r un on-line was developed to simulate the leak, to read and filter the pressure transducers data, to display the pressure transient plots and to obtain leak location information. The detection system showed good performance in the detection of small leaks. Leaks as small as 5% of the nominal liquid flow rate are readily detected. Leak locations were computed from pulse time delay between the various pressure transduce rs. The computed leak positions approached the actual values with prec ision. The developed software shows to be a very useful tool to the au tomatic supervision of pipelines as instantaneous leaks are readily de tected and located.