k-epsilon simulations of the neutral atmospheric boundary layer: analysis and correction of discretization errors on practical grids
The Reynolds-averaged NavierStokes equations/ k -e approach is the popular and practical choice for carrying out simulations involving the atmospheric boundary layer. However, despite its widespread use, implementation of this approach is not without its challengeseven when considering the simplest case of horizontally homogeneous conditions. Most notably, the distributions of turbulent kinetic energy and its dissipation rate have proved difficult to maintain near solid boundaries, particularly in wind engineering applications where the near-wall grid is relatively coarse. In this work, the origin of these errors is investigated, and it is shown that by applying appropriate discretization schemes in conjunction with the Richards and Hoxey boundary conditions, truly invariant profiles of all flow properties can be obtained on such grids. Furthermore, with this finding, a wall treatment for coarse grids is proposed that could be implemented for non-homogeneous conditions. All simulations are carried out using OpenFOAM-1.6.x. Copyright (c) 2011 John Wiley & Sons, Ltd.
atmospheric boundary layer discretization error wall treatment computational fluid dynamics k?-?e turbulence model finite volume method