DOI: 10.1615/TSFP4
NUMERICAL PREDICTION OF SHOCK INDUCED OSCILLATIONS OVER A 2D AIRFOIL: INFLUENCE OF TURBULENCE MODELLING AND TEST SECTION WALLS
RESUMO
The present study deals with recent numerical results from on-going research conducted at ONERA/DMAE regarding the prediction of transonic flows, for which shock wave/boundary layer interaction is important. When this interaction is strong enough (M≥1.3), Shock Induced Oscillations (SIO) appear at the suction side of the airfoil and lead to the formation of unsteady separated areas. The main issue is then to perform 2D unsteady computations applying appropriate turbulence modelling and relevant boundary conditions with respect to experimental ones. Computations were performed with the ONERA object-oriented software elsA, using the URANS-type approach, closure relationships being achieved from transport-equation models. Applications are provided for the OAT15A airfoil data base (Jacquin et al., 2005); tests were conducted in the ONERA S3 Chalais Meudon wind-tunnel equipped with self-adaptive upper and lower walls. These experiments are rather well documented for unsteady CFD validation (r.m.s. pressure, phase-averaged data, ...). URANS results have emphasized the importance of modelling the test section geometry when carrying out 2D unsteady computations to (i) capture SIO as precisely as possible and, (ii) objectively evaluate the capabilities of turbulence models to predict such flows.