May 20, 2024 at 2:02 pm
Rob
Forum Moderator

You mean wall function? Or variable roughness height? The former is covered here https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v241/en/flu_udf/flu_udf_ModelSpecificDEFINE.html%23flu_udf_sec_define_wall_functions