High Accuracy Installation for Flow Meter Calibration with Weighing Method

Abstract

One of the most important characteristics of the fluid flow meter is its accuracy. In order to determine the highest possible accuracy of the flow meter, it is necessary to calibrate the flow meter on an adequate installation. It is necessary that installation for precise flow meter calibrations meets demands of the relevant standards: quality installation, appropriate calibration methodology, instruments of high accuracy and satisfactory measurement uncertainty. Designed and manufactured installation for flow meters calibration (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 created 3D model 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 production. The test rig was manufactured after the numerical results evaluation. Flow measurement experimental results and measurement uncertainty for three operating regimes are analyzed and reported. It was shown, both experimentally and numerically, that uniform flow is achieved in the straight measurement section. This is of great importance for flow measurement calibration.