基于紧凑型D-D中子发生器的热中子照相慢化准直器设计  

Design of Moderator-collimator for Thermal Neutron Radiography Based on Compact D-D Neutron Generator

作　　者：于筱雪 王俊润 刘兴宇 郑永光 张宇[1,2] 韦峥[1,2] 姚泽恩[1,2] YU Xiaoxue;WANG Junrun;LIU Xingyu;ZHENG Yongguang;ZHANG Yu;WEI Zheng;YAO Zeen(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China;Research Center for Neutron Application,Ministry of Education,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学核科学与技术学院,兰州730000 [2]兰州大学中子应用技术教育部工程研究中心,兰州730000

出　　处：《原子核物理评论》2023年第2期251-256,共6页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11875155,12075105);兰州大学中央高校基本科研业务费专项资金资助项目(lzujbky-2022-kb09)。

摘　　要：热中子照相是一种重要的无损检测技术,是X射线照相技术的重要补充,小型化热中子照相系统有重要研究应用前景。基于紧凑型D-D中子发生器,采用蒙特卡罗程序MCNP-4C,通过中子和γ射线的输运模拟,完成了热中子照相慢化准直器的模拟研究与设计。慢化准直器准直比约为3.58,模拟研究结果显示,在D-D中子发生器中子产额大于5×10^(8)n/s条件下,样品平面内热中子注量率可大于10^(3)n/(cm^(2)·s),准直中子束中热中子占比可大于74%,在Φ70 mm的照射视野范围内,热中子注量的不均匀度约为7.3%,基本满足热中子照相的成像要求。Thermal neutron radiography is a powerful nondestructive detecting technique as an important complement to Xray radiography.The miniaturized thermal neutron radiography system holds great potential in research and industrial applications.Based on the compact D-D neutron generator,a neutron moderator-collimator for thermal neutron radiography was designed and simulated by using Monte Carlo N-Particle Transport Code(MCNP-4C)to track neutrons andγ-rays.The aspect ratio of the moderator-collimator was about 3.58.The simulation results showed that the thermal neutron flux rate could reach and exceed 10^(3) n/(cm^(2)·s)in the sample plane when the neutron yield of D-D neutron generator is greater than 5×10^(8) n/s.The proportion of thermal neutron in the collimated neutron beam was found to be over 74%.In a irradiation field with a diameter of 70 mm,the non-uniformity of thermal neutron flux was kept at 7.3%,which meets the imaging criteria of thermal neutron radiography.

关 键 词：热中子照相 紧凑型D-D中子发生器 慢化准直器 

分 类 号：TL816[核科学技术—核技术及应用]