Leakage is a major issue facing all the water companies. In some areas, it results in the loss of 30% of the water passing through treatment plants. Unfortunately, leaks are difficult to locate and any methods involving digging trenches to expose the pipe are extremely costly both in terms of labour and disruption to traffic, particularly in urban areas. Therefore any leak detection and location method which does not involve access to the pipe, other than at existing access points such as valves etc, is potentially extremely valuable. Since all pipes have access points at intervals along their length (valves etc), the use of measurements at these sites to infer the condition of the pipe between them is potentially very attractive. Acoustic waves will travel as guided waves along a pipe system so measurement of these is a promising approach which is exploited in correlators. These instruments, which measure the vibration produced by leaking water which is transmitted along the pipe to access points where accelerometers can be located, are valuable tools which are increasingly used. This project aims to improve our understanding of wave propagation in buried water pipes and so to indicate how more information could be extracted from correlator or related measurements.

PC WITE training pres.ppt

Acoustic wave propagation

Acoustic wave propagation

Sponsors

EPSRC, Thames Water, North West Water, andNorthumbria Water

References

Long, R.S., Cawley, P. and Lowe, M.J.S. 'Acoustic wave propagation in buried iron water pipes', Proc Royal Soc Lond: Mathematical, Physical and Engineering Sciences, Vol 459, pp2749-2770, 2003.

Long, R., Lowe, M.J.S. and Cawley, P. ‘Attenuation characteristics of the fundamental modes that propagate in buried iron water pipes’, Ultrasonics, Vol 41, pp509-519, 2003.

Long, R., Vogt, T., Lowe, M.J.S. and Cawley, P. 'Measurement of acoustic properties of near-surface soils using an ultrasonic waveguide', Geophysics, Vol 69, pp460-465, 2004.

C Aristegui, M J S Lowe, P Cawley, "Guided waves in fluid-filled pipes surrounded by different fluids",Ultrasonics, vol. 39, pp. 367-375, 2001.