Statistical Analysis of the Sixth AIAA Drag Prediction Workshop Solutions

Abstract

A graphical framework is used for the statistical analysis of the results from an extensive N-version test of a collection of Reynolds-averaged Navier–Stokes computational fluid dynamics codes for the Sixth AIAA Computational Fluid Dynamics Drag Prediction Workshop in June 2016. The solutions were obtained by code developers and users from North America, Europe, Asia, and South America using both common and custom grid sequences, as well as multiple turbulence models. The aerodynamic configuration for the workshop was the Common Research Model, which is a subsonic transport wing–body previously used for both the Fourth and Fifth Drag Prediction Workshops. This work continues the statistical analysis begun in the earlier workshops and compares the results from the grid-convergence study of the most recent workshop with previous workshops. Most notably, the results demonstrate that predicted drag increments show less scatter between codes than the predicted absolute values of drag for a given configuration, and also serve to reinforce a lesson learned from the Fifth Drag Prediction Workshop regarding the importance of a common grid sequence in decreasing the solution variation regardless of the computed output quantity.