关键词: 分离流，稳定性，重复性

Abstract: Based on the Reynolds-Averaged Navier-Stokes equations with $k$-$\omega$ SST turbulent model and coupled with the motion equations for an elastic supported system, the steady and unsteady flows for airfoils with different incidences are simulated, specially, for high incidences when separated vortices exist. For the given Reynolds numbers and structure parameters considered in this paper, the frequencies of shedding vortex have a complicated relation with the airfoil vibration. The average aerodynamic force may vary for some forced vibrations. For airfoils with thickness larger than 20{\%}, the aeroelastic response can lead to a separated flow field from one balance state to another so that the aerodynamic force changes from one value to another. These results can explain the poor repeatability of experimental results in these regions.

Key words: separated flow, stability, repeatability