一种基于混合传导模型的一回路结构材料腐蚀-活化-迁移模型及其应用

为了定量分析反应堆冷却剂加锌工艺对一回路系统堆芯外放射性水平的影响,本文结合描述材料微观腐蚀过程的混合传导模型(MCM)和描述腐蚀产物活化、迁移及沉积的宏观输运模型,形成了能够系统性描述一回路结构材料腐蚀-活化-迁移的联合模型,并通过遗传算法分析及文献调研确定模型各主要参数。经校验表明该模型能够有效计算正常运行工况下一回路中结构材料的均匀腐蚀程度,同时也能给出结构材料表面沉积层的放射性活度分布。使用该模型对加锌前后系统内不同分区的活度分别进行了计算,结果表明加锌工艺能显著降低一回路堆芯外放射性水平。

A Model for Zinc Addition Effect on Corrosion Product Release,Activation and Transportation in RCS Based on Mixed-conduction Model and Its Application

The mixed-conduction model (MCM) was used to characterize the microscopic corrosion process of primary structure materials. The results combined with the macroscopic transporting model characterizing the activation, migration and deposition processes of corrosion products was investigated in order to study the effect of reactor coolant zinc application on the radiation field reduction expectations in the reactor coolant system (RCS). A combined model was established which could quantitatively depict those processes and the pivotal parameters of the model were obtained through genetic algorithm analysis and literature studies. Then the model's algorithm was calibrated and showed that it could effectively calculate the effect of zinc addition on activation, migration and deposition processes of corrosion products and could also carry out radioactivity distribution for the primary side. The radioactivity of different regions of RCS was also calculated using this model. The results showed that zinc addition strategy could significantly reduce the radiation field for out-of-core region.