On the initial investigation of the use of temperature gradient measurements to estimate the presence of leaks

Resumo

Leakage in water pipes is of great concern, so that techniques for its detection have been widely studied
over the years. In this scenario, vibro-acoustics techniques are the most used ones because they can be no intrusive,

can provide information on the amplitude (severity) and location (time delay) of leaks in buried pipes with reason-
able precision, however, requiring the use of equipment and instrumentation of high cost in addition to the training

of specialized labor workers. The latter may restrict the application of this kind of solution to a few specialized
companies. Hence, the initial investigation of detecting leaks via using temperature gradient measurements is
proposed in this work as an attempt to develop a technique that is less costly but still effective in indicating the
existence of leaks. This initial investigation is carried out using a straight-horizontal water plastic pipe generally
found in ordinary houses, so that the heat transfer mechanism of such situation can be modeled via finite volume
method (FVM) considering steady-state condition and the developed code (situations) validated using the software
OpenFoam. The simulations were carried out considering a range over which the Reynolds number relies within
according to the average leak flow rates commonly found in ordinary residential buildings in Brazil. Moreover, the
Nusselt and temperature gradient were then evaluated regarding their variability in the fully developed flow region,
as a function of the variation of the external environment condition.