Abstract: Neutronics calculations based on homogeneous and high-fidelity models for CFETR helium-cooled ceramic breeder (HCCB) blanket have been performed, and results are summarized in this paper, including tritium breeding rate (TBR), neutron spectrum, power distribution and etc. The neutronics effect of homogeneous structure and space self-shielding effect on CFETR HCCB are performed. Also, neutronics effect on the size of the pebbles to the TBR is studied. Results show that the homogeneous model has small impacts on the neutronics performance of CFETR HCCB blanket, the space self-shielding effect of the pebble beds shows a descending trend when the diameter of pebbles decreases and the space self-shielding effect caused by pebble beds has little effect on the neutronics performance of CFETR HCCB blanket. Finally, the results verify that the homogeneous model for neutronic analyses of the HCCB blanket are rational, and the design basis for the high-fidelity neutronic calculation has been provided.

Key words: CFETR HCCB, Neutronics, Tritium breeding ratio, Homogenization, Space self-shielding effect.

摘要： 在CFETR氦冷固态包层及球床结构的最新概念设计方案中，基于均匀化模型、仅球床均匀化模型与高保真模型分别进行了中子学计算分析。研究了结构均匀化及球床空间自屏效应对包层中子学影响以及小球尺寸对氚增殖比的影响。结果表明，(1) 结构均匀化模型对氦冷包层中子学影响较小；(2) 随着小球直径的减少，球床空间自屏效应堆氚增殖比的影响逐渐降低；(3) 氦冷包层真实尺寸下的小球产生的空间自屏效应较低，可忽略不计。

关键词: CFETR氦冷包层, 中子学, 氚增殖比, 均匀化, 空间自屏效应