基于计算流体力学的近岸海域放射性核素弥散模型研究

Study on offshore dispersion of radionuclides using computational fluid dynamic model

建立了基于计算流体力学的三维近岸海域放射性核素弥散模型,以实现对放射性核素浓度分布的精细模拟。通过与法国La Hague核燃料后处理厂排放含氚废水的海面监测数据对比,验证了本模型的正确性,并与MARS(Hydrodynamical model for applications at regional scale)模型进行精度对比和分析。结果表明:在小尺度(<5 km)范围内,本模型的计算结果与监测数据较为吻合,误差控制在15%以内,模拟精度略优于MARS模型;在地形与水文条件复杂的近岸海域,本模型可用于预估核设施事故或常规排放所造成的辐射后果,为核应急响应决策提供技术支持。

A computational fluid dynamics（CFD）-based three-dimensional offshore radionuclide-dispersion model was established to simulate the distribution of radionuclide concentration. Variations in the simulated concentration of tritium released from the La Hague nuclear fuel reprocessing plant demonstrated good agreement with surface-monitoring data, thereby effectively validating the proposed method. In addition, an accuracy comparison and analysis were performed using MARS（Hydrodynamical model for applications at regional scale）. The results showed that the calculation results of this model agreed well with the monitoring data in a small scale（〈5 km）. The error was controlled within 15%, and the simulation accuracy was slightly better than the MARS model. And results obtained reflected the ability of the proposed model to precisely simulate the radionuclide dispersion process performed in offshore waters with complex topography and hydrological conditions, thereby confirming its applicability in the prediction of the effects of radiation caused by nuclear accidents and/or conventional emissions. This would provide essential technical support during the decision-making process in the event of a nuclear emergency.