Abstract: In this paper, a nuclear power plant is taken as the research object. The computational fluid dynamics (CFD) method is used to study the influence of natural ventilation cooling tower on the flow and pollutant diffusion around the nuclear power plant, and the results are compared with the wind tunnel experiment results to verify the validity of the model. The results show that on the leeward side of the cooling tower, the wind speed in the near wake region (including the re-circulation zone) decreases significantly, and the turbulence intensity increases significantly. When the cooling tower is located in the downwind direction of the stack, the plume emission has a great influence on the pollutant diffusion of the stack. The pollutant is naturally sucked through the cooling tower, and the secondary emission phenomenon occurs. When there is plume emission, the ground axis diffusion factor is less than that without thermal plume emission before 1 000 m.

Key words: cooling tower, plume, flow field, concentration field, numerical simulation