Unsteady separated flows over manoeuvring lifting surfaces

Numerical simulations of dynamic-stall phenomena have been performed using an implicit unfactored Navier-Stokes solver and various turbulence closures , including linear and nonlinear low-Re eddy-viscosity models. The accuracy of the models has been assessed against a range of experimental data for r amping and oscillating aerofoils at subsonic and transonic conditions. The computations indicate that the non-linear eddy-viscosity models better pred ict the shedding of the dynamic-stall vortex and the unsteady aerodynamic l oads.