Proposal of Innovative Leak Sensing Systems for Water Distribution Networks

This paper describes two innovative, simple and low cost sensing systems to detect possible leaks in a pressurized fluid distribution network, such as an urban aqueduct. Both techniques may use micro-sensors (MEMS) of different nature, the first one sensing vibrations, the second one sensing pressures. The first technique bases its principle on the comparison of vibration signals acquired at the terminals of arbitrary long but continuous pipe under test. Differences in the amplitudes, at the same characteristic frequency, of the acquired signals would indicate leaks of fluid at some location between the sensors. The leading idea comes out from the linear relationship existing between the radial acceleration amplitude transmitted by the (turbulent) flow to the pipe walls and its flow rate. The second methodology principle is based instead on the measurement of the fluid pressure gradients acquirable in correspondence of two suitable consecutive elbows present along a continuous pipe, because of its functional dependence on the flow rate through it. In addition, in this case, a difference in the detected pressure signals would indicate a leakage between the elbows. Both methods involve the use of wireless MEMS, accelerometers or pressure transducers respectively, to drastically reduce the cost of the monitoring and inspections of great fluid distribution networks, in particular, with respect to traditional technologies. The goal of the proposed methodologies is also to significantly decrease the inspection times that are typically required by traditional leak detection methods, especially for large networks. Applications are easily expected as well in industry.