LARGE EDDY SIMULATION OF THE FLOW PAST PITCHING NACA0012 AIRFOIL AT 1E5 REYNOLDS NUMBER

The paper is concerned with the prediction and analysis of dynamic stall of flow past pitching NACA-0012 airfoil at 105 Reynolds number based on the chord length of the airfoil and at reduced frequency of 0.188 in a three dimensional flow field. The turbulence in the flow field is resolved using large eddy simulations with dynamic Smagorinsky model at the sub grid scale. The lift hysteresis plots indicate closer match to experimental results, although discrepancies exist during the downstroke. The development of dynamic stall vortex, vortex shedding and reattachment as predicted by the present study are discussed in detail. This study has shown that the downstroke phase of the pitching motion is strongly three dimensional and is highly complex, whereas the flow is practically two dimensional during the upstroke.