Proposition of water meter for buildings based on a thin-film resistive sensor: electromechanical and thermal characterizations

Abstract

Abstract Notoriously, measurement proves to be essential to encourage water conservation. Thus, this work characterizes two thin-film resistive sensors (bend sensors) with different coatings aiming at their application to measure water consumption. For this, the individual water measurement system is presented and discussed briefly. Then, resistive sensor parameters and operating principles are detailed, as well as the mathematical formulation of the correlation of the sensor resistance with the flow velocity. Methodologically, the system developed for the electromechanical and thermal characterization of the sensor is presented. The results allowed obtaining a quadratic relationship between the sensor deflection angle and the resistance. Furthermore, it was observed that the polyester-coated sensor presented a low hysteresis value when subjected to temperature variation, obtaining a negative linear relationship between the sensor resistance and temperature. In turn, the polyimide-coated sensor did not show low hysteresis when exposed to temperature change and flexed at 50° and 70° angles. Finally, it is proposed for future work computer simulations and experimental tests to confirm the applicability of the sensor for water measurement.