托卡马克聚变中子源的数值模型研究

Numerical Model of Tokamak D-D/D-T Fusion Neutron Source

托卡马克(Tokamak)聚变装置中子学分析中,聚变中子源描述是重要的输入参数,其准确性直接影响分析结果的可靠性。通过分析ITER和欧洲聚变示范堆(EU DEMO)中子学分析中所采用的聚变中子源模型,提出了一种完整描述Tokamak中L-mode、H-mode等离子体的D-D、D-T聚变中子源的数值模型。在中国聚变工程实验堆(CFETR)的工程集成设计平台上,编写了基于蒙特卡罗算法的程序SCG求解该数值模型,实现了读取(零维)等离子体参数、输出可供典型中子学软件MCNP直接读取的中子源定义文件的功能。以CFETR氦冷球床包层的中子学分析模型为基准,在相同的L-mode等离子体D-T聚变工况下,相较于采用EU DEMO源子程序,采用本模型计算得到的中子壁负载差异最大值为2.02%,包层氚增殖率差异为0.18%,全堆能量增益因子的差异为0.23%。结果表明,本模型与其他源描述的差异较小,可应用于CFETR的中子学分析。

In Tokamak fusion neutronics,the fusion neutron source description is one of the initial inputs,which affects the neutronics analysis result.Based on the study of fusion neutron source model used in ITER and EU DEMO,a numerical model that uses a set of formulae to describe the LH-mode plasma D-D/D-T fusion neutron source was addressed.Within the framework of engineering design platform for China Fusion Engineering Test Reactor（CFETR）,source card generator（SCG）was developed to solve the numerical model utilizing Monte Carlo method,by which a set of plasma physics parameters were read and the SDEF card for MCNP code was produced.On the basis of neutronics analysis on CFETR with helium cooled pebble bed blanket,neutron wall loading,the tritium breeding ratio and global energy multiplication factor resulting from the SCG-produced SDEF card are of differences at 2.02%,0.18% and 0.23%,respec-tively,compared with those resulting from EU DEMO source subroutine in L-mode D-T fusion scenario.This numerical model of Tokamak D-D/D-T fusion neutron source and the SCG can be used in the neutronics calculation of CFETR.