Non-iterative wall model formula for non-equilibrium boundary layer flows

A novel non-iterative (explicit) formulation of generalized wall functions that applies to equilibrium and non-equilibrium boundary layer flows was proposed. The proposed formulation uses a set of variables that are more useful for computational fluid dynamics codes as they allow for calculating wall shear stress without an iterative procedure. In addition, an explicit form of the formulation was provided that applies to wall models with and without pressure gradients. The new variable transformation casts the generalizedwall function into a new form that simplifies the implementation and evaluation of wall-shear stress in computational codes.