Sensitivity analysis for numerical simulations of disturbed flows aiming ultrasonic flow measurement

A detailed parametric sensitivity analysis reveals the effect on the numerically calculated profile factor of ultrasonic flow meters of various modeling parameters such as mesh refinement, boundary conditions, turbulence model, wall treatment, interpolation schemes and numerical integration. The flow field is solved using a commercial CFD code and the profile factor is obtained by numerical integration of the three velocity components along the acoustic path. Interesting relations of these numerical parameters concerning the inertia of the flow are observed, suggesting that the higher the Reynolds number, the more precaution is needed in the simulation of pipe flows, especially when the goal is to infer the profile factor of ultrasonic flow measurements, which are related to strict uncertainties. The main finding is that quantitative conclusions may be mistaken or distorted if a proper analysis of how sensitive the simulation results are with respect to its modeling parameters is not carried out.