Effects of Shape Change due to Wear on the Accuracy of Vortex-Shedding Flow Meters

摘要

In the present investigation, the problem of accurate determination of volumetric flows by means of the so-called vortex-shedding flowmeter in the case of shape changes from the original specifications due to wear was studied. To this end, the flow about the bluff body used in the presently studied vortex-shedding flow meter was numerically simulated using a solver of the unsteady, compressible Navier-Stokes equations in two and three dimensions. The computations were carried out for several Reynolds numbers using modified geometry in which rounded edges representing wear were introduced. The results were compared, where possible, with experimental data obtained by the manufacturer. The effects of turbulence were modeled by using the realizable k-ε turbulence model. The resulting flow fields were analyzed using various methods, including visualization, evaluation of several of their global features and DFT of properly chosen variables.