Application of the non-linear eddy viscosity model to wind flow around a high-rise building in the surface boundary layer

This paper compares the results from CFD simulations using the standard κ-ε model, the LK model and the non-linear κ-ε model proposed by Craft applied to wind flow around a high-rise building in the surface boundary layer. The accuracy of these three models was examined by comparing their results with experimental data. Compared with other two models, the non-linear κ-ε model proposed by Craft cannot obtain a converged solution for steady calculation; and the result given by unsteady calculation using Craft model shows the best agreement with the experiment. On the one hand, the Craft model can improve the prediction of the turbulence kinetic energy in the upwind impingement region, hence it can reproduce the reverse flow on the building roof; on the other hand, the Craft model can reproduce the vortex shedding behind the building, hence it predicts a shorter reattachment length behind the building than the LK model. The reattachment length behind the building given by Craft model is close to that given by the standard κ-ε model.