Computational Modeling of Flow Rate Measurements Using an Orifice Flow Meter

This study is concerned with understanding and improvement of mass flow rate measurement uncertainty and errors encountered at low flow rates and start-up in commercially available flow rate measurement devices, such as orifice flow meters. The flow through a typical cylindrical flange-tapped orifice flow meter is modeled computationally so the actual mass flow rate is known a-priori. Empirical predictions from the reading of “virtual” pressure sensors are compared with the actual flow rate and the measurement errors are quantified and analyzed. Commercial code ANSYS-Fluent is compared in this study to the in-house high-fidelity spectral-element solver Nek5000, so that conclusions about the applicability of a commercial code to the calculations of measurement uncertainty in the orifice flow meters can be made.