Non-equilibrium wall-functions and enhanced wall treatment approach comparison in flat-plate turbulent boundary layer

In this paper, the effect of using two approaches on boundary layer modeling on a flat-plate has been evaluated using the RNG k- model. Approaches include non-equilibrium wall function and enhanced wall treatment method. The results of numerical models in two different mesh sizes (coarse and fine) are compared with experimental outputs. Fluid flow has been simulated using ANSYS-Fluent® with coupled algorithm. Non-dimensional wall parameter, non-dimensional velocity and wall friction coefficient results are indicated both for numerical models and experimental study in boundary layer and viscous sub-layer. While investigating the flow behavior in the viscous sublayer, the enhanced wall treatment approach has better performance. In the fully turbulent zone, both models predict the flow behavior well. The results of the enhanced wall treatment approach are independent of the mesh size and y+ of the first element adjacent to the wall. Also outputs indicate a better and more rapid convergence for enhanced wall treatment approach in comparison with non-equilibrium wall function results.

کلیدواژه ها:

Turbulent Boundary Layer ، RNG k- ، Non-Equilibrium Wall Function ، Enhanced Wall Treatment ، Reynolds Scaling