Novel water flow facility in france range extension to low flow rates (10 000 ml/h down to 1 ml/h)

In order to extend the French water flow calibration range, LNE-CETIAT is on progress to build a new reference for flow rate measurements ranging from 10 000 ml.h−1 down to 1 ml.h−1. This new facility based on a gravimetric principle will enable calibration with water temperature between 10 °C and 50 °C. Flow is regulated by the combined use of a tightly regulated “upstream” pressure (0,1 to 10 bar) and the use of capillaries under laminar flow. The expected relative uncertainty for the water flow rate is 0.1 % with a coverage factor k = 2 (95% confidence). The paper described the design and the ongoing implementation of this new calibration facility.