Numerical Modeling of Wind Distribution Around a Tall Building in a 3D Urban Environment

This work applies an appropriate turbulence model in order to simulate the wind distribution in a 3D urban area around a tall building as a bluff body, which is one of the most important research topics due to the increasing concerns about the human health risks due to air pollution in the recent decades. The hybrid RANS-LES approach is used to reduce the computation time, while maintaining the computational accuracy. On the other hand, since no homogeneous direction exists in the flow in the hybrid (RANS-LES) approach, the LES and Smagorinsky Sub Grid-Scale (SGS) approaches are implemented with the standard k-epsilon turbulence model as RANS. In order to obtain more accurate results, the second-order Van Leer Method (VLM) is employed in advection terms. The sensitivity study of the input parameters shows that the intensity of the input turbulence has a significant effect on the surface pressure fluctuations. The results of velocity and pressure distribution show a very close agreement to the wind tunnel experimental data. Finally, the effects of the inflow characteristics on the peak pressure on the lateral sides are also studied. As a results, the fluctuation pressure distribution is strongly dependent on the turbulence of the flow.