Gridgen's boundary conditions and Fluent
 

Hi all,

I am using Gridgen and Fluent and i have a problem with assigning boundary conditions in Gridgen: after generating with Gridgen a structured grid around an airfoil, i set the "wall" boundary condition for the upper and lower surface of the airfoil: but when i open my grid in Fluent (after creating the corresponding case file), Fluent no longer distinguishes the upper surface of the airfoil from the lower one: indeed Fluent considers the upper and lower surfaces as a single wall, whereas i want these surfaces remain two distinct walls.

Anyone can help me?

Thanks in advance