  The detection of leaks in pipeline transportation systems is a matter of
serious concern for operators, who pursue the integrity of their assets, the
reduction of losses and the prevention of environmental hazards. Whenever a
hole occurs in a pressurized pipeline, the corresponding fluid leakage is
characterized by a turbulent flow and a peculiar acoustic noise, whose
characteristics depend also on the size of the hole itself. This study shows
that both the presence and the size of such a leaking hole can be successfully
detected, by exploiting the acoustic noise (pressure transients) generated by
the fluid exiting the pipe and recorded internally by hydrophones, or by
considering the corresponding vibrations (e.g., acceleration signals)
propagating along the external shell of the conduit. To this purpose, several
experimental campaigns of acoustic noise generation have been performed using
multiple calibrated nozzles on a 16 ID connection pipeline in a fuel tanks
area. Detection and classification procedures are proposed to control the
presence of leakages and to estimate the size of the hole, using pressure and
vibration signals.
