NUMERICAL INVESTIGATION OF DYNAMIC STALL OF AN OSCILLATING WING

The unsteady three-dimensional flowfield over an oscillating wing is i nvestigated with the numerical solution of the compressible, time-depe ndent, Reynolds-averaged Navier-Stokes equations. Spatial discretizati on is performed with a third order accurate, upwind-biased, vertex-bas ed, finite volume scheme. An alternative direction implicit, iterative scheme is used for the time Integration. The high Reynolds number tur bulent flow behavior is modeled with a one equation turbulence model, The effect of subiterations, time step and grid density on the accurac y of the computed solutions is investigated. It is found that scaling of the time step with the angular velocity of the motion produces accu rate solutions at a reduced computational cost. The computational doma in over an aspect ratio 5 wing with rounded tip and NACA-0015 airfoil sections is discretized with a single-block grid, The light stall flow field over the wing oscillating in a subsonic freestream with a mean a ngle of attack of 11 deg and an amplitude of 4.2 deg is computed. The structure of the separated, unsteady flowfield is investigated and com parisons with available experimental data are performed.