Turbulence modelling of the flow past a pitching NACA0012airfoil at 10^5 and 10^6 Reynolds numbers

G. Martinat (1) , Marianna Braza (1) , Yannick Hoarau (2) , Gilles Harran (1)

1 IMFT - Institut de mécanique des fluides de Toulouse
2 IMFS - Institut de Mécanique des Fluides et des Solides

This paper provides a study of the NACA0012 dynamic stall at Reynolds numbers 10 5 and 10 6 by means of two and three dimensional numerical simulation. The turbulence effect on the dynamic stall is studied by statistical turbulence modelling. The results are compared with experiments concerning each test case. Standard URANS turbulence modelling have shown a quite dissipative character that attenuates the instabilities and the vortex structures related to the dynamic stall. The URANS approach OES, Organised Eddy Simulation, has shown an improved behaviour at the high Reynolds number range. Emphasis is given to the physical analysis of the three dimensional dynamic stall structure, for which there exist few numerical results in the literature, as far as the Reynolds number range is concerned. This study has shown that the downstroke phases of the pitching motion are subjected to strong three-dimensional turbulence effects along the span, whereas the flow is practically two-dimensional during the upstroke motion.

Domaines: Mécanique des fluides [physics.class-ph]

G. Martinat, Marianna Braza, Yannick Hoarau, Gilles Harran. Turbulence modelling of the flow past a pitching NACA0012airfoil at 10^5 and 10^6 Reynolds numbers. Journal of Fluids and Structures, 2008, 24 (8), pp.1294-1303. ⟨10.1016/j.jfluidstructs.2008.08.002⟩. ⟨hal-02612126⟩