Installation for the high accuracy flow meter calibration with the weighting method

Abstract

Installation for precise flow meter calibrations meets demands of the relevant standards: high-quality installation, appropriate calibration methodology, instruments of high accuracy and satisfactory measurement uncertainty. So, it is necessary to calibrate the flow meter on an adequate installation. Designed and assembled installation for flow meters calibration for measurement of liquid flow in closed conduits up to 10 l/min, based on weighing method, is presented in this paper. Modified measurement methodology, which mainly follows standard ISO 4185, is presented in this paper. The geometry of the whole installation is presented and afterwards used for numerical experiments. Two numerical meshes were tested. First approach had a half a million cells and the second mesh was consisted of approximately 1.6 million cells. Both meshes were unstructured. Numerical results were used for installation test before manufacturing and assembling. The test rig was manufactured after the numerical results evaluation. Experimental validation of the calibration procedure followed. Obtained experimental results and measurement uncertainty for three operating regimes were analysed and reported. It was proved, experimentally and numerically, that uniform, i.e. developed turbulent flow, was achieved in the straight measurement section, what is of great importance for flow measurement calibration.