Numerical simulation of transonic buffet flows using various turbulence closures

The paper presents a numerical investigation of buffet flows using various turbulence models, including linear and non-linear low-Re eddy-viscosity mo dels (EVM). The accuracy of the models is assessed against experimental dat a for transonic flows around the NACA-0012 aerofoil. The study shows that n on-linear two-equation models in conjunction with functional c(mu) coemcien t for the calculation of the eddy-viscosity (henceforth labelled NL-c(mu)), provide satisfactory results for transonic buffet nows. The computations a lso reveal that the Spalart-Allmaras one-equation model provides comparable results to the NL-c(mu), models, while larger inaccuracies are introduced by linear and non-linear models based on constant c(mu) coemcient. Moreover , the buffet onset boundaries are similarly predicted by the one-equation a nd NL-c(mu) models. The study has been performed using a second-order time accurate implicit-unfactored method which solves in a coupled fashion the N avier-Stokes and turbulence transport equations. The spatial discretisation of the equations is obtained by a Riemann solver in combination with a thi rd-order upwind scheme. (C) 2000 Begell House Inc. Published by Elsevier Sc ience Inc. All rights reserved.