Fluent 12 k-w SST turbulence model
 

Hi everyone,

I am using the k-w SST turbulence model to predict unsteady flow of a NACA0012 airfoil pitching at a fixed rate. I am trying to understand how this turbulence model toggles between resolving the viscous sublayer and using a wall function. Ive done a bit of searching around here and it seems that there should be a radio button that toggles transitional flow on/off but I do not see it at all in this version of Fluent 12. There is one radio button in the viscous model box that says low-Re correction, which according to the manual says should be on when resolving the sublayer, but dosent give a definite explaination as to how the model toggles between the two modes. Does anybody have any idea.

And also, how does the accuracy of your solution compare when using a wall function vs resolving all the way to the viscous sublayer?

Thank you for your help in advance.