NUMERICAL STUDY ON VELOCITY-PRESSURE FIELD AND WIND FORCES FOR BLUFF-BODIES BY KAPPA-EPSILON, ASM AND LES

Velocity- pressure fields and wind- induced forces on and around a building model are analyzed by means of numerical simulations. In this study, three types of well- known turbulence models, namely k-epsilon Eddy Viscosity Model (k-epsilon EVM), Algebraic Stress Model (ASM) and Large Eddy Simulation (LES) are used. In the first half of the paper, three - dimensional dimensional (3D), time- averaged flowfields around a cube within a surface boundary layer are predicted using these three turbulence models with similar boundary conditions. The accuracy of these simulations is assessed by comparison with results of wind tunnel tests. The results of LES show the best agreement with the experimental data. In the latter part, unsteady flowfield around a square prism is predicted by LES. Results of 2D and 3D computations are compared with experimental data. It is confirmed that the results of the 3D computation correspond very well to the experimental ones, while the results of the 2D computation include some significant discrepancies.