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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.

It is known that the presence of trapped air within water distribution pipes can lead to irregular operation or even damage to the distribution systems and their components. The presence of trapped air may occur while the pipes are being filled with water, or while the pumping systems are in operation. The formation of large air pockets can produce the water hammer phenomenon, the instability and the loss of pressure in the water distribution networks. As a result, it can overload the pumps, increase the consumption of electricity, and damage the pumping system. In order to avoid its formation, all of the trapped air should be removed through "air trap valves". In Brazil, manufacturers frequently have unreliable sizing charts, which cause malfunctioning of the "air trap valves". The result of these malfunctions causes accidents of substantial damage. The construction of a test facility will provide a foundation of technical information that will be used to help make decisions when designing a system of pipelines where "air trap valves" are used. To achieve this, all of the valve characteristics (geometric, mechanic, hydraulic and dynamic) should be determined. This paper aims to describe and analyze the experimental apparatus and test procedure to be used to test "air trap valves". The experimental apparatus and test facility will be located at the University of Campinas, Brazil at the College of Civil Engineering, Architecture, and Urbanism in the Hydraulics and Fluid Mechanics laboratory. The experimental apparatus will be comprised of various components (pumps, steel pipes, butterfly valves to control the discharge, flow meter and reservoirs) and instrumentation (pressure transducers, anemometer and proximity sensor). It should be emphasized that all theoretical and experimental procedures should be defined while taking into consideration flow parameters and fluid properties that influence the tests.