wall functions implementation for turbulent flows
Are the wall functions correlations being applied only in the first cells from the wall?
What about the rest of cells in the boundary layer region?
The wall functions are aplied only in the first layer of cells from the wall. For standard or nonequillibrium wall functions, the mesh is coarse enough so that the first layer of cells cover most of the boundary layer.
When using the enhanced wall treatment, in which case the mesh actually resolves the boundary layer region, there is an additional procedure which
takes into account the special calculations in the turbulent boundary region.
A Re based on the distance from the wall is computed dynamically by the code and for cells with Re<200
the turbulent diffusivity is computed in a different way than in the core region (see 10.8.3 - two-layer for
enhanced wall treatment).