The Application of Computational Fluid Dynamics to the Diffusion of Gas–Aerosol Emissions in Conditions of Complex Terrain
https://doi.org/10.1134/S2304487X1906004X
Abstract
This paper presents the simulation of airflow around a set of typical obstructions (three-dimensional cube and hemisphere, as well as a two-dimensional hill) by means of ANSYS FLUENT package within the framework of the standard (k–ε) turbulence model. The obstructions represent the buildings and typical landforms in the area of nuclear power plant emissions. To ensure the convergence of the results, we used a non-uniform spatial grid on the computational domain, which thickened near the obstruction surface and the outer boundaries. The size and position of the obstruction were chosen to best match the conditions of the published experiments. The result of modeling the velocity and direction of the air flow as a whole reveals a good agreement with the experimental data in wind tunnels in the areas in front of the obstacle, above it, as well as in its aerodynamic shadow. Characteristic zones of accelerated flow, vortices and reverse flow are reliably reproduced. The length of the turbulence zone of the leeward side of the cube is the maximum in comparison with the hill and hemisphere. Unlike the latter, the cube also forms a turbulent zone with the separation of the flow over the upper plane of the roof. Differences with experiments are observed only in local areas of strong turbulence in the aerodynamic shadow of an obstacle near the ground surface. All this opens the possibility of a full-fledged simulation of the diffusion of nuclear power plant emissions, taking into account the terrain features of the site of a particular station and its main building in order to refine the personnel and public exposure.
About the Authors
M. Mehdi
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)
Russian Federation
Russian Federation
115409
Moscow
M. P. Panin
National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)
Russian Federation
Russian Federation
115409
Moscow
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Review
For citations:
Mehdi M., Panin M.P. The Application of Computational Fluid Dynamics to the Diffusion of Gas–Aerosol Emissions in Conditions of Complex Terrain. Vestnik natsional'nogo issledovatel'skogo yadernogo universiteta "MIFI". 2019;8(6):546-552. (In Russ.) https://doi.org/10.1134/S2304487X1906004X
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