Plans and suggestions of a verification case to the AIAA aeroelastic prediction workshop

Resumo

© 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.To asses the state of art and best practices in computational aeroelasticity (CAe) for static and dynamic phenomena is the key objective of the AIAA Aeroelastic Prediction Workshop series (AePW). The workshop is an excellent opportunity for academia and in- dustrial exchange through transparent discussions and collaborative learning on relevant aeroelastic topics. During the second edition of the event (AePW-2), held in January 2016, the efforts were concentrate on unsteady aerodynamics and utter prediction for the Benchmark Supercritical Wing (BSCW). Three transonic cases were proposed: steady and unsteady forced aerodynamics under attached flow; utter on set prediction for weak shock attached flow condition; and a third more challenging case of transonic detached flow with steady, forced pitch oscillations and utter on set prediction. The workshop discussions pointed to some relevant issues in CAe while analyzing the participants results: turbulence modeling, temporal convergence, mesh convergence and fluid-structural coupling effects. Each analysis team explored some of those aspects, but not a consensus was established as best practices for numerical setup. As Computational Fluid Dynamics (CFD) become massive parallel processed, the number of grid points applied to relatively simple geometry as the BSCW becomes millions quickly. Parametric numerical studies of unsteady aero- dynamics and aeroelasticity including viscous effects in such meshes become too expensive for most researchers or industries and the physics of fluid flow and dynamics analysis can go to second plan faced the computational efforts to run and post-process such amount of generated data, risking to loose the engineering feeling of the analysis. This paper proposes the inclusion of a verification study case for the upcoming AePW editions in a lightweight 2D configuration, where some of the questions raised during the AePW-2 could be parametrically clarified regarding the CFD turbulence modeling, fluid-structure coupling and time and grid convergence. The aim is to explore the flow physics and see how the numerical setup behaves, identifying the limitations of the CFD methodologies applied, before jump into a fully 3D buffet aeroelastic configuration. The first results of this initiative are presented here as a CFD characterization of the BSCW airfoil section in steady, unsteady, unsteady forced and utter cases for the transonic regime of interest. All the data, models details and meshes are made available for the research community.