Document Type : Original Article


Department of mechanical engineering, Yazd Branch, Islamic Azad University, Yazd, Iran.


This study applies an appropriate turbulence model 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 human health risks due to air pollution in recent decades. Hybrid RANS/LES approach, was used to reduce computation time while maintaining 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) approach are implemented with the standard k-ε turbulence model as RANS. To obtain more accurate results, the second-order Van Leer Method (VLM) was 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 showed a very close agreement to wind tunnel experimental data. Finally, the effects of the inflow characteristics on the peak pressure on the lateral sides is also studied. As the results, fluctuation pressure distribution was strongly dependent on the turbulence of the flow.


Main Subjects

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