TOPAZ-Ⅱ地面样机源项研究

本文基于TOPAZ-Ⅱ反应堆,研究了热离子空间堆地面样机的源项。利用MCNP统计地面样机的能谱,将能谱作为CINDER程序的输入,计算了反应堆堆芯放射性源项总量,并利用ANS/ANSI-2011的模型计算了气体裂变产物的释放产生比,确定了地面样机系统内的源项分布。结果表明热离子空间堆地面样机堆芯源项远小于压水堆核电站,随着运行温度的升高气体裂变产物的释放比显著升高,大量气体裂变产物由堆芯迁移到裂变气体收集系统。

This paper researches the source term of thermionic space reactor based on TOPAZ-II. CINDER is used to calculate the total source term of the ground prototype using the energy spectrum counted by MCNP. Then the model described in ANS/ANSI-2011 is used to determine the birth to release ratio of the volatile fission products and the distribution of the source term within the ground prototype is given. The result shows that the total source term of the ground prototype is far less than that of nuclear power plant. The birth to release ratio of the volatile fission product rises rapidly as the fuel operation temperature increases, a considerable amount of volatile fission products will mitigate from the core to the gaseous fission products collection system.