兆瓦级热管核反应堆屏蔽方案设计研究  

Shielding design of a megawatt-scale heat pipe reactor core

作　　者：王永平[1] 陶昱姗 吴云钦 郑友琦[1] 杜夏楠 WANG Yongping;TAO Yushan;WU Yunqin;ZHENG Youqi;DU Xianan(Xi'an Jiaotong University,Xi'an 710049,China;Nuclear Power Institute of China,Chengdu 610213,China)

机构地区：[1]西安交通大学,西安710049 [2]中国核动力研究设计院,成都610213

出　　处：《核技术》2023年第2期111-124,共14页Nuclear Techniques

基　　金：国家重点研发计划(No.2019YFB1901102)资助。

摘　　要：无人潜航器需要高可靠、高功率、长寿命的电源,为此西安交通大学提出了兆瓦级热管核反应堆(Silent Unmanned Portable Reactor,UPR-s)设计方案。为保证舱体辐射安全,对UPR-s开展了屏蔽方案设计研究工作。首先,对整个系统及屏蔽体的布局进行初步设计,并分别计算了反应堆满功率运行和停堆情况下的源项参数;其次,给出几种备选屏蔽材料;接着,利用确定论中子-光子屏蔽计算软件NECP-Hydra分别针对初始模型布置选型、复合式屏蔽布置选型及阴影屏蔽布置方案等进行计算分析,主要对安全平面处的累计快中子注量、光子剂量,以及停堆后的源强进行了分析;最终,基于数值分析结果,提出了满足要求的屏蔽优化方案,其安全平面处的累积快中子注量、光子剂量、屏蔽重量等关键参数均满足设计限值。[Background]According to the requirements of unmanned underwater vehicles for high reliability,high power,and long-life power,the design scheme of the megawatt heat pipe nuclear reactor silent unmanned portable reactor (UPR-s) is proposed by Xi’an Jiaotong University.[Purpose]This study aims to design the shielding scheme for UPR-s to ensure the radiation safety of the cabin.[Methods]First of all,according to the UPS-s scheme applied to the underwater unmanned vehicle (UVV),the layout of the nuclear system and shielding was designed,and the source terms of the reactor core under both full power and shutdown status were calculated by using NECP-SARAX code.Then,initial shielding model was established with consideration of several alternative shielding materials.The deterministic neutron-photon shielding calculation code NECP-hydra was employed to analyze several shielding schemes:the initial model layout,composite shielding layout,and shadow shielding layout.Finally,the accumulated fast neutron fluence,photon dose and source intensity at the safety plane were analyzed,and a shielding optimization scheme meeting the requirements was proposed on the basis of the numerical analysis results.[Results]Calculation results of shielding optimization scheme show that the maximum accumulated fast neutron fluence and photon dose of the safety plane at full power are 9.48×1011n·cm-2and 7.29×10~5 rad,respectively.Under shutdown conditions,the maximum safe plane dose rate is 0.004 49 m Sv·h-1,and the total weight of core plus shielding is 296.35 kg.[Conclusions]The key parameters of optimized shielding scheme,including the cumulative fast neutron fluence,photon dose,and total shielding weight,satisfy the given design requirements.

关 键 词：无人潜航器 热管核反应堆 屏蔽 快中子注量 光子剂量 

分 类 号：TL32[核科学技术—核技术及应用]