Hi friends I want you please ask you how can I use law of wall in fluent in my case I working in 3D with cars and I don´t know how is the set up to simulate boundary layer Thank you Adrian

you chekc the Y-plus, which should be in a certain range according to the turbulence model you choose, if not, re-generate the grid

law of the wall, i assumed you mean the wall-function, read the material, then you will understand how to deal with it