[suktan]

Hello,


I have a question for CFD newbie. When we use wall-function for y+ >= 40, we don't care wall friction at all in simulations. For 40 > y+ >= 5, we both (shear stress and inertial) considered. Is this description correct? Thank you.

[LuckyTran]

You definitely care about wall shear stress otherwise you would be using a slip wall and using no stress as the boundary condition.

All wall boundary conditions are some form of wall function. It's meaningless to talk about wall functions unless you are talking about a specific implementation or a particular wall function. You also need to state which transport equation is your wall function being applied to.