A CFD study on radionuclides diffusion and dose assessment in Daya Bay nuclear power plant

Computational fluid dynamics (CFD) is used to simulate the short-range dispersion of radionuclides in a real nuclear power plant site. Firstly, the results of the validation case showed that the wind speed and concentration distribution were consistent with the measured data. Then, the potential consequences of radionuclide diffusion within the Daya Bay Nuclear Power Plant (DBNPP) were evaluated. Based on the wind direction and speed data from DBNNP over a 30-year period, the prevailing wind is northeasterly and southwesterly. The simulation results show that northeasterly and southwesterly winds dominate the diffusion direction of radionuclides, which mainly accumulate near nuclear reactor containment vessels. However, radionuclides cover most areas of DBNPP under a tailwind condition, causing severe contamination. Finally, it is necessary to pay attention to the accumulation of I-131 and Cs-137, and corresponding actions should be taken for regions of different radiation doses. © 2024 Elsevier Ltd.