Verification of Calculations: an Overview of the 2nd Lisbon Workshop

摘要

This paper presents an overview of the 2nd Workshop dedicated to the Verification of Calculations held in Lisbon in October 2006. The Workshop aimed at evaluation of Uncertainty Estimators in Computational Fluid Dynamics for incompressible fluids in two two-dimensional flows: a manufactured solution that mimics a near-wall turbulent flow and the flow over a backward facing step. Seven groups submitted results obtained with various numerical methods including finite-volume, finite-element and finite-difference approaches. The evaluation of the uncertainty estimators was favorable for the Manufactured Solution where it is not difficult to attain the asymptotic range. It was found, among other things, that for the Spalart &: Allmaras turbulence model the observed order of accuracy is not equal to the theoretical order of the method. The results for the physical problem were less conclusive because of differences in models, and especially because of the apparent inability of the participants to reach the asymptotic range.