一种新的放射性核素迁移弥散系数计算方法

研究放射性核素在饱和被压实缓冲/回填材料中的迁移对于核废物处置具有十分重要的意义,为了用数学模拟的方法准确地对放射性核素迁移进行描述和预测,首先必须精确地求出有关的放射性核素迁移参数——弥散系数、吸附系数等,其中最重要之一就是弥散系数。目前确定放射性核素在被压实缓冲/回填材料中迁移弥散系数的方法主要有经验公式法和示踪实验。本工作结合放射性核素铀迁移的室内实验,应用概率理论计算了被压实缓冲/回填材料中核素迁移水动力弥散系数,讨论了被压实缓冲/回填材料水动力弥散系数和地下水流速对放射性核素在被压实缓冲/回填材料中迁移的影响。最后总结分析了具体的实现步骤。

A New Calculation Method of The Diffusion Coefficient of Radionuclide Migration

It is very important to study on radionuclide migration in compacted buffer/backfill material. In order to describe and predict the radionuclide migration by the method of mathematical simulation, it is necessary to solve the important parameters of radionuclide migration-diffusion coefficient. Up to now, the main research ways of diffusion coefficient are the empirical formula and experimental. Based on some experimental data of radioactive nuclide migration, the paper calculates the diffusion coefficient of radionuclide migration in compacted buffer/backfill material by applying the theory of probability, discusses the effect of diffusion coefficient and subsurface-flow on the property of radioactive nuclide migration. Finally, steps for the new calculation method of the Diffusion Coefficient are provided.