基于严重事故剂量后果的堆芯重要核素选择

Significant Isotopes Selection of Core Inventory Based on Severe Accident Radiological Dose Consequence

用于事故放射性后果评价的事故源项与堆芯源项密切相关,而通用的堆芯源项程序,如ORIGEN的计算结果包含几百个甚至更多的核素,如何在大量核素中筛选出重要核素,对于简便、准确地进行放射性后果评估具有重要意义。通过对事故后核素迁移至环境的跟踪,评价每个核素对最终放射性后果的贡献。结果显示30～50个核素的剂量贡献即可包络95%以上的剂量后果,这些核素可作为计算的基准,也是堆芯源项核素选择的依据。计算方法对剂量后果评价具有重要的参考价值。

Accident source terms used to evaluate the postulate accident radiological consequence closes relate to the core inventory.The results of core inventory calculation codes,such as ORIGEN,include hundreds of isotopes,even more.So how to select significant isotopes among large amounts of original data seems particularly important for conveniently and precisely assessing radiological consequence.By tracking the isotopes transportation to environment,the dose contribution of each isotope was calculated.The results show that only 30-50 isotopes can bound 95% contributions to dose consequence,these isotopes can be the base of radiological consequence calculation and core inventory source terms selection.The method mentioned may provide a reference to review the general postulate accident radiological consequence.