聚变驱动次临界堆双冷嬗变包层中子学设计与分析

对聚变驱动次临界堆的多功能双冷核废料嬗变包层进行了中子学设计和分析,设计目标是:①氚和钚燃料自持;②较少的初装料得到较高的废料嬗变率。使用的程序是自主开发的多功能中子输运/燃耗/优化程序VisuaIBUs1.0,相应的数据库是175群中子/42群光子的多群数据库HENDL1.0/MG。     

聚变驱动次临界堆双冷嬗变包层结构设计与分析

给出聚变驱动次临界堆液态金属LiPb/He气双冷嬗变包层参考结构概念,采用了低活化铁素体/马氏体RAFM钢(如CLAM)作为结构材料、简单液态金属流道、两个独立氦气冷却系统以及燃料球/颗粒等设计方案。重点分析了嬗变包层第一壁、重金属区与裂变产物嬗变区的结构设计特点。     

基于遗传算法的聚变驱动次临界堆嬗变包层长寿命锕系元素初装料中子学优化

在聚变驱动次临界堆的多功能核废料嬗变包层中,长寿命锕系废料的嬗变处理是中子学设计中非常关心的问题。利用FDS课题组开发的多功能中子学程序系统VisualBUS1.0,针对该系统燃耗计算过程具有多变量和多目标函数复杂关系的特点,应用遗传算法对嬗变包层的锕系废料嬗变区的初装料量进行了优化处理,使其在一定的物理和工程参数约束下,指导嬗变区的装料份额取值,分析嬗变区的装料份额对锕系废料的年燃耗深度等参数的影响。     

聚变驱动次临界堆双冷嬗变包层热工水力学参数设计与分析

聚变驱动次临界堆双冷嬗变包层是一个以氦气和液态金属LiPb为冷却剂,以嬗变核废料为主要目的的多功能包层。依据功率平衡模型对不同工况优化的基础上,对该包层热工系统参数进行了设计分析。采用三维商用计算流体力学程序对第一壁和高功率密度区中液态LiPb的流场进行数值模拟计算,给出了优化的典型热工水力参数。     

聚变驱动次临界堆嬗变包层双流场三维数值模拟与分析

采用流体动力学数值模拟软件对聚变次临界堆双冷嬗变包层高功率密度区 (FW、HM1 )液态金属LiPb和氦气流场进行三维数值模拟 ,考察双流场温度分布、LiPb向氦气传热热流密度场等 ,为聚变次临界堆热工水力学设计提供决策依据     

聚变次临界堆双冷嬗变包层第一壁结构和氦气流道优化分析

在聚变次临界堆双冷嬗变包层第一壁结构初步设计基础上 ,对第一壁结构尺寸和氦气流道形状进行优化分析 ,利用有限元分析软件对第一壁结构进行应力数值模拟 ,在满足结构应力及部件可靠性的前提下 ,给出最佳优化方案。     

聚变裂变混合堆钍基增殖锕系元素嬗变包层中子学初步研究

聚变裂变混合堆比纯聚变堆在工程及技术方面要求低,且在产生核燃料、嬗变长寿命核废料以及固有安全性方面具有一定优势,因此,越来越受到人们的重视。增殖包层是混合堆系统的关键部件,已有的包层研究基本上是基于较成熟的铀-钚燃料循环技术。针对我国铀资源相对较少而钍资源较丰富的现状,本文就一种新型的钍基燃料增殖锕系元素嬗变包层进行了初步的中子学研究,利用一维离散纵标法燃耗程序BISONC以及Monte-Carlo粒子输运程序MCNP,对包层的关键核参数,诸如氚增殖比、少量锕系元素的嬗变质量、233U产量以及热功率等,进行了较详细的计算分析。计算结果表明,生成的核燃料233U的富集度可达到3.65%,从而满足压水堆燃料富集度要求。分析结果为下一步的包层优化设计提供了依据。     

聚变驱动次临界堆双冷嬗变包层材料活化计算与分析

对聚变驱动次临界堆 (FDS Ⅰ )包层进行了材料活化计算与分析。利用多功能中子学程序系统VisualBUS1 .0及多群数据库HENDL1 .0 /MG进行中子输运计算 ,以获得包层各个功能区的中子注量率能谱 ;在此基础上 ,使用欧洲活化计算程序FISPACT及IAEA聚变活化数据库FENDL/A 2 .0分别对停堆初期包层不同功能区的剂量率水平和衰变余热水平、停堆后期结构材料与氚增殖剂 /冷却剂的活化性能及其杂质的控制要求进行了计算及分析。     

聚变驱动次临界堆双冷嬗变包层第一壁结构热应力计算与分析

使用有限元程序对聚变次临界堆双冷嬗变包层第一壁进行数值模拟 ,给出不同载荷条件下的温度场和应力场分布 ,结果证明典型氦气系统设计满足热工要求。依据数值模拟结果对第一壁氦气载热能力进行分析 ,并考虑了流道形状对结构热应力的影响。     

次监界聚变嬗变堆高性能双冷包层中子学概念设计研究

基于聚变实验装置近期可达到的堆芯ＤＴ等离子体参数水平,在一维燃耗计算和优化分析的基础上,验证了氚自持、年约处理２９ 个同等热功率压水堆年产的长寿命锕系元素和一定数量裂变产物的次临界聚变嬗变堆带有双冷却系统高性能包层的中子学可行性,并给出了初步的设计方案。     

聚变驱动次临界堆经济性分析

利用自主开发的聚变系统分析软件SYSCODE对聚变驱动次临界堆的经济性进行了计算和分析。首先,对典型的环径比(标准环径比)设计方案,从堆芯几何参数、物理及工程参数等两个方面分析它们与成本的关系,然后,详细分析低、标准、高环径比三套候选设计方案的经济性与中子学参数的关系。研究发现,其经济性主要取决于包层中子学参数,另外,其经济性与几何、物理及工程参数的关系在一定条件下有别于纯聚变系统。     

Neutronics analysis of minor actinides transmutation in a fusion-driven subcritical system

The minor actinides (MAs) transmutation in a fusion-driven subcritical system is analyzed in this paper. The subcritical reactor is driven by a tokamak D-T fusion device with relatively easily achieved plasma parameters and tokamak technologies. The MAs discharged from the light water reactor (LWR) are loaded in transmutation zone. Sodium is used as the coolant. The mass percentage of the reprocessed plutonium (Pu) in the fuel is raised from 0 to 48% and stepped by 12% to determine its effect on the MAs transmutation. The lesser the Pu is loaded, the larger the MAs transmutation rate is, but the smaller the energy multiplication factor is. The neutronics analysis of two loading patterns is performed and compared. The loading pattern where the mass percentage of Pu in two regions is 15% and 32.9% respectively is conducive to the improvement of the transmutation fraction within the limits of burn-up. The final transmutation fraction of MAs can reach 17.8% after five years of irradiation. The multiple recycling is investigated. The transmutation fraction of MAs can reach about 61.8% after six times of recycling, and goes up to about 86.5% after 25.     

聚变驱动次临界堆双冷嬗变包层多群中子截面数据库共振自屏效应计算与分析

依据聚变驱动次临界反应堆 (FDS I)系统设计方案 ,使用Njoy和Transx程序 ,制作了 2 5群、1 75群、62 0群忽略和考虑共振自屏效应的中子截面核数据库 ,用Anisn程序计算了系统的有效增殖系数和各种反应率。结果表明 ,共振自屏效应对FDS I系统的各种反应率有很大的影响。     

Fusion-driven transmutation of selected long-lived fission products

The long-term radiological burden associated with nuclear power production is usually attributed to long-lived fission products (LLFP). Their lifetime and large equilibrium mass and hence radioactivity accumulated in the course of fission energy generation make their storage a rather formidable task to solve. Therefore the idea of artificial incineration of LLFP through their transmutation has been quite naturally incorporated into the concept of self-consistent nuclear energy system (SCNES) based primarily on fast breeder reactor technologies. However it is now acknowledged that neutron environment of fission facilities including fast breeder reactors does not seem most appropriate for LLFP transmutation. The issue has been then extensively developed within the framework of multi-component self-consistent nuclear energy system (MC-SCNES). Neutrons of specific quality required for LLFP transmutation are proposed there to be of non-fission origin. Given neutron excess available and neutron quality, a fusion neutron source (FNS) is appearing as the candidate No. 1 to consider for LLFP transmutation. Research on LLFP transmutation by means of FNS has very long history and has received an additional boost during the decade passed. In the present study, potential of thermal flux blanket of FNS is exemplified by transmutation of ⁹³Zr and ¹²⁶Sn, the most difficult LLFP to transmute. It is shown that transmutation of ⁹³Zr is effective even with a rather modest neutron loading of 1 MWt·m⁻², typical for ITER project. Transmutation of ¹²⁶Sn, however, requires neutron loading of as high as 3 MWt·m⁻² for DD fusion and is quite unattractive for DT fusion. In the latter case, transmutation through the threshold (n,2n) reaction may be preferable.