Optimization of flow rate measurement using piezoelectric accelerometers: Application in water industry

• The standard deviation of the vibration of accelerometers increases with the flow rate.
• FIV consists of measuring the vibrations induced by the passage of the fluid through the pipeline.
• Flow rate measurements are estimated and optimized from the standard deviation of FIV signal.
• Uncertainty evaluation in calibration curves adjusted for second-degree polynomials is discussed.
• Water flow rate measurements by accelerometers meet the specifications of Brazilian Metrology Institute.

This paper presents a method for measuring flow rates in pipelines based on the flow induced vibration principle using water as fluid, eliminating the need for interrupting the flow and opening of the pipeline for installation of traditional water flow meters. Experimental measurements are carried out in an accredited laboratory for calibration of rate flow meters and a metrological validation, followed by an uncertainty evaluation, are presented. Data analysis is accompanied by a method of optimization that minimizes adjustment errors of measurement using regression by parts and by the selection of the optimum period to estimate more accurately the flow rate. The results meet the specifications of Brazilian Metrology Institute.