Tehran University of Medical Sciences Journal of Air Pollution and Health 2476-3071 6 2 2021 12 11 117 134 EN Yi Yang Department of Environmental Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, P R China Tianxiao Zhang Department of Environmental Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, P R China Haiying Xie Department of Environmental Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, P R China Xiaoxiao Wang Department of Environmental Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, P R China 2021 09 28 2021 11 13 Introduction: The impacts of building layout on pedestrian level wind comfort and gas pollutant diffusion are simulated using computational fluid dynamics method. Materials and methods: The control equations of flow and pollutant diffusion are solved by using ANSYS Fluent. The SIMPLE algorithm is selected for the pressure-velocity coupling. The data from wind tunnel experiment at Tokyo Polytechnic University is employed in the validation case. Results: The velocity field and turbulence intensity at pedestrian level under different building layouts are obtained. The distribution and evaluation of wind comfort grade and pollutant concentration are given. Conclusion: Building layouts have significant impacts on flow and pollutant diffusion at pedestrian level. The outward staggered layout of building group can improve both wind comfort grade and air quality, but the inward staggered layout has the adverse effect. Non-staggered layouts are the worst in terms of the wind comfort grade in this paper. https://japh.tums.ac.ir/index.php/japh/article/view/299 https://japh.tums.ac.ir/index.php/japh/article/download/299/279