Numerical studies on active flow circulation controlled flap concept for aeronautical applications

Four different circulation controlled airfoils have been numerically simulated. The baseline airfoil was a 17% thick supercritical airfoil. Different blowing rates have been examined by adjusting the slot height and blowing velocity. A number of turbulence models were employed, these were: Spalart-Allmaras, standard κ-ε, realizable κ-ε, SST κ-ω and Reynolds stress model. The results from the numerical simulation were compared with experimental data at zero angle of attack. The solutions indicated that at momentum coefficients, Cμ = 0.1 or greater, all isotropic turbulence models failed to capture the physics of the circulation control problem. Only Reynolds stress model captured successfully the physics at Cμ = 0.1. At greater values of momentum coefficient, Reynolds stress model also failed to predict the experimentally measured lift coefficient, because the jet remained attached to the surface of the airfoil. © 2004 by Zacharos A, Kontis, K.