Development of a Dynamic Gravimetric Calibration Method for Liquid Water Flow Metering

According to its mission of national reference laboratory, LNE-CETIAT maintains and develops the French standard for liquid water flow meters calibration from 1g.h-1 to 36 t.h-1. The reference calibration facilities at LNE-CETIAT are historically based on the flying start and stop gravimetric method. Because of the specificity of micro-flow rates, two separated and dedicated calibration benches are used for flow rates from 1 g.h-1 to 10 kg.h-1 on one side, and from 8 kg.h-1 to 36 t.h-1 on the other side. Continuous improvement of the calibration capabilities pushes LNE-CETIAT to upgrade the existing methods toward a dynamic measurement of the reference flow rate, in the scope of EURAMET EMPIR "METROWAMET" JRP in which CETIAT is a partner of the consortium. After a short review of the state of the art and a description of the current LNE-CETIAT's, this paper will first present the development of a dynamic liquid flow generator required to ensure the measurand's representability. In a second part, the development of a dedicated and traceable measurement system, based on the existing gravimetric test rig, is described. Finally, the first feasibility test is presented and future developments are proposed.