[sniperees]

Hi there,

I am currently trying to model 3 airfoils in 2D, NACA 4421, NACA 23012 AND GOE462, using ICEM. Now, at the moment, when I'm running the simulations, my coefficient of lift is good, very accurate (ie < 2.5% off) while my coefficient of drag is always two times greater than what the experimental data says. I’ve tried almost everything (to my knowledge, I’m still fairly new), double checking y plus values, changing models (I use SST and SA without low Re damping since my velocity at inlet is 45m/s.) I’ve tried coarsening and refining the mesh, and the coefficient of drag usually stays the same. I’ve noticed that there isn’t a lot of tutorials for the way I’m doing it, ie tetra meshing and prism layers. However there is a lot of tutorials for blocking or hexa meshing? I’m not sure what its called. In your opinion, would there be much difference in the results, and is it easier to use hexa meshing to get more accurate results?

Thanks