Water Flow Meter Measurement Uncertainties
Free (open access)
313 - 322
R. P. Dias, J. G. Dalfré Filho & Y. F. L. de Lucca
In water supply systems, managers need to get water from a source and supply an entire population. Knowledge regarding the flow of water is a critical parameter within these systems, thus the need for flow meters. When flow meters are placed near pipeline singularities, the velocity profile changes and can cause measurement errors. Due to these potential errors, measurement norms and standards are created to require flow meters to be placed in rectilinear-shaped pipelines for a more accurate measurement. However, managers claim that in field measurement situations, it is not always possible to meet these standards, and consequently, adjusting the error from the acquired data is necessary. Therefore, this study investigates how the error in the flow rate varies with the distance from singularities when using an ultrasonic flow meter, which, as a nonintrusive measurement method, is easily installed on the outside walls of the pipeline. This flow meter was installed at different distances from an elbow and the measurements obtained were compared to those from an electromagnetic flow meter, which accumulate accurate data when installed at standard conditions. Comparing the data from those two flow meters, it was possible to obtain the variation of error as a function of flow and distance from the singularity. Keywords: uncertainties, ultrasonic flow meter, water supply systems.
Keywords: uncertainties, ultrasonic flow meter, water supply systems.