A Low-Cost Flexible Pipe Sheath for Multi-Parameter Monitoring of Water Distribution

Abstract

A pervasive diffusion of wireless sensors distributed in the environment can be sustained by a significant reduction of the cost of the transducers. Water represents a fundamental resource whose management can be optimized by real-time monitoring, especially in agriculture (irrigation). To this aim we present a low-cost flexible pipe sheath to detect water leakage, as well as conductivity and temperature, by means of contactless impedance measurements. Finite-element simulations show the potential to detect water leaks as small as 1 liter across a pipe length of 2 m, corresponding to a 1% change of a 5 kΩ impedance at 1 kHz, easily detectable by off-the-shelf impedance chips.

Contactless Sensing of Water Properties for Smart Monitoring of Pipelines

“…The number and size of electrodes were chosen as a compromise among competing requirements: (i) maximization of sensitivity to leaks [ 12 ], (ii) minimization of the metal area, and (iii) homogenous coverage of the surface. For the pipe of 90 mm diameter, four electrodes connected in alternate couples were selected ( Figure 2 a).…”

“…Recently, we have proposed to use impedance to identify water leakage by means of longitudinal electrodes detecting leaks due to the change in ionic conductivity of the soil surrounding the pipe [ 12 ]. Differently from techniques mapping the soil impedance for the surface [ 13 ], here we sense a local variation of soil conductivity along the pipe.…”

A Pipe-Embeddable Impedance Sensor for Monitoring Water Leaks in Distribution Networks: Design and Validation

“…The first step was to define a realistic geometry for the simulation domain. It was improved with respect to [ 16 ], where the wet volume was assumed to be a simple 10 cm 3 cube placed on the electrodes. Initially, a seepage profile was tested ( Figure 2 a) by extruding a bidimensional circular sector along a length L Leak matching the arc segment C Leak (hence L Leak = C Leak ) and later separating it into distinct material layers, with a similar approach for the 45 cm-long electrode pair at first.…”

“…Electrodes can be applied on pipes already installed, in specific segments where leakage risk is higher, hence simplifying their installation. The starting point of this work was a very preliminary and rudimentary simulation showing the feasibility of the impedimetric approach [ 16 ]. Interestingly, a similar approach has been proposed for power cables [ 17 ], as well as for indoor leak monitoring with dielectric tape [ 18 ].…”