Development of adaptive wall functions for an elliptic-blending model

Abstract

The paper presents the development and validation of adaptive wall functions that allow local “downto-the-wall” resolution based on a three-equation plus elliptic-blending eddy-viscosity model. Two wall-treatments are proposed: 1/ the wall function values are applied as boundary conditions (local treatment) or 2/ the wall function profiles are applied over a range of cells in the wall vicinity (zonal treatment aimed for unstructured meshes). The proposed wall treatments are designed to allow the model predictions to be independent of the type of wall unstructured mesh-refinement to be used. To assess this property, oneand two-dimensional channel flows are computed for several types of meshes. To test the zonal treatment, the method is also applied on meshes with an arbitrary amount of consecutive inner nodes “removed”. Lastly the case of heat transfer in a ribbed wall passage with mixed coarselyand finely-meshed regions is considered.