The assessment of the radiological impact of the liquid discharges from nuclear power plants is a major issue for the environmental protection. In this study, a numerical model for the radionuclide transport in the aquatic environment is built, based on the hydrodynamic equations, including the complete set of Saint-Venant equations, the sediment transport equations, with consideration of several different particle sizes and the deposition and erosion of the suspended sediments, and the radionuclide transport equations. The exchanges of radionuclides between water, suspended matter and bed sediments are described in terms of kinetic transfer coefficients. The model is used to simulate the transport of the radionuclides discharged from a planned nuclear power plant project to be sited along the lower Yangtze River. From the model results, one may see the detailed temporal-spatial evolution of the radio- nuclide contamination in the solution, in the suspended matter and in the bed sediments. The model can be used as a basic tool for studying the environmental impacts of the liquid discharges from nuclear facilities on a river system.

中文翻译：

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长江下游核素迁移的二维数值模拟

核电厂液体排放物的放射学影响评估是环境保护的一个主要问题。在这项研究中，基于流体动力学方程，包括完整的Saint-Venant方程组，沉积物迁移方程，并考虑了几种不同的粒径以及沉积和沉积过程，建立了水环境中放射性核素迁移的数值模型。悬浮沉积物的侵蚀以及放射性核素的迁移方程。水，悬浮物和床沉积物之间的放射性核素交换用动力学传递系数来描述。该模型用于模拟沿长江下游规划的核电站项目排放的放射性核素的传输。根据模型结果，人们可能会看到溶液，悬浮物和床层沉积物中放射性核素污染的详细时空演变。该模型可用作研究核设施液体排放对河流系统的环境影响的基本工具。