Author(s)

K. A. Ahmad, W. McEwan, J. K Watterson & J. Cole

Abstract

The RANS code Fluent 6TM is used to predict the flow field around a pitching NACA 0012 airfoil. Experimental data for this unsteady flow field is widely available for validation. A hybrid mesh was employed in the computational domain and different mesh configurations were tested and the results were compared. Several turbulence models such as k-
and k-ω were tested and the results were also compared. The turbulence model that gives the best agreement with the experimental data is SST k-ω with y+ value set to 1. Mesh and time step dependence studies were also performed and it was found that the results were not affected by varying these parameters. Nomenclature cl Drag coefficient cd Lift coefficient cm Pitching moment coefficient k Turbulence kinetic energy F+ Reduced frequency L Length of the object w Natural frequency y+ Local Reynolds number α Angle of vibration αmax Maximum angle of pitch αmin Minimum angle of pitch dα Range of the angle of pitch
Dissipation rate of turbulence ω Specific turbulent dissipation rate

Keywords