基于堆外中子能谱测量的堆芯中子场反演方法  

An inversion method of in-core neutron field based on ex-core neutron spectrum measurement

作　　者：甘佺 曹佩 郝丽娟[1] 宋婧[1] 龙鹏程[1] 俞盛朋[1] 吴斌[1] 孙光耀[1] 吴宜灿[1] FDS凤麟团队 GAN Quan;CAO Pei;HAO Lijuan;SONG Jing;LONG Pengcheng;YU Shengpeng;WU Bin;SUN Guangyao;WU Yican;FDS Team(Key Laboratory of Neutronics and Radiation Safety,Institute of Nuclear Energy Safety Technology,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]中国科学院核能安全技术研究所中子输运理论与辐射安全重点实验室

出　　处：《核技术》2019年第9期53-59,共7页Nuclear Techniques

基　　金：中国科学院信息化专项(No.XXH13506-104)、中国科学院合肥物质科学研究院项目(No.KP-2017-19);中国科协青年人才托举工程(No.2017QNRC001)资助~~

摘　　要：目前商用反应堆堆内采用的自给能探测器(Self-Powered Detector,SPD)可以实现堆芯中子通量分布的在线测量,但难以测量中子能谱。同时由于一些先进反应堆堆内服役环境更加恶劣,现有的堆内测量系统难以满足先进反应堆堆芯中子场在线测量的需求。本文提出了一种基于堆外中子能谱测量的堆芯中子场反演方法,通过正向中子输运计算构建堆芯相邻截断面之间的能谱响应矩阵,实现反应堆堆芯中子场的反演计算。通过采用两个简化的反应堆模型进行验证,其中对压力容器处反演的中子能谱与蒙特卡罗输运计算结果平均相对偏差约为14%,在外层燃料组件区域反演的中子能谱与蒙特卡罗输运计算结果平均相对偏差约为11%,初步验证了本方法的可行性。[Background]The self-powered detectors(SPD)are widely used in commercial reactor for the real-time measurement of neutron flux distribution,but neutron spectrum cannot be obtained by SPD.Meanwhile,due to the extreme condition of advanced reactor systems,the existing in-core measurement systems cannot meet the requirement of real-time measurement of neutron field in the core of advanced reactor.[Purpose]This study aim to develop an inversion method of in-core neutron field based on ex-core neutron spectrum measurement.[Methods]First of all,Monte Carlo calculation method was employed to obtain the spectrum response matrix between adjacent truncated planes in the core by forward neutron transport calculation.Then,the in-core neutron field could be inversed.Finally,two simplified reactor models were used for method verification and validation.[Results]For the neutron field in the pressure vessel,the average relative deviation between the inversion result and the Monte Carlo transport computation result was about 14%,and for the neutron field in the external fuel region,the average relative deviation was about 11%.[Conclusion]The inversion method of in-core neutron field proposed in this paper preliminarily demonstrated the feasibility of the method for neutron spectrum monitoring in the reactor core.

关 键 词：堆芯中子通量 堆外中子能谱 能谱响应矩阵 反演 先进反应堆 

分 类 号：TL329.2[核科学技术—核技术及应用]