分类: 能源科学 >> 能源(综合) 分类: 核科学技术 >> 裂变堆工程技术 分类: 核科学技术 >> 粒子加速器 分类: 核科学技术 >> 乏燃料后处理技术 提交时间: 2024-06-30
摘要: Accelerator Driven sub-critical System (ADS) is considered to be the most important candidate for nuclear waste transmutation. We propose a Multi-Target Accelerator Driven System (MTADS) to resolve two longstanding challenges of ADS, namely heat removal and the associated target lifetime, and inhomogeneous power distribution that affects burn-up of the reactor. An 18 mA, 1 GeV proton beam is split into 12 beams by radio frequency cavities and injected to 12 compact targets inside the reactor. With beam power of 18 MW, the sub-critical reactor is driven to 1500 MW thermal power. The peaking factor of the reactor is reduced to 1.7 by optimization of targets number and position for Multi Target Accelerator Driven System. The maximum beam current density is also reduced to 18.5 μA/cm2, which prolongs the beam window lifetime to 12 months with T91 steel. Towards the next generation ADS, the concept of MTADS simplifies the sub-critical system and increases the transmutation efficiency.
分类: 物理学 >> 核物理学 分类: 核科学技术 >> 乏燃料后处理技术 提交时间: 2023-06-20
摘要: 第一性原理被应用在核工程领域关注的热中子散射材料的热中子截面计算中,本文以Al和Bi金属的热中子截面制作为例,分别基于第一性原理冷冻声子法和密度泛函微扰法,采用VASP结合PHONONY程序计算了它们的声子色散关系和声子态密度,基于NJOY程序,在LEAPR中添加Bi相干散射处理,制作了Al和Bi的热中子散射截面库,结果表明:对于Al,相较于冷冻声子法,密度泛函微扰理论的声子态密度得到的热中子散射截面与ENDF8.0符合更好,对于Bi,采用密度泛函微扰法消除了冷冻声子法的虚频现象,得到的热中子散射结果与实验值符合较好。本文从探索材料内部特征机理的角度提出了一种更基础、更有预见性的制作热中子截面的方法,为研究新型反应堆的核材料热化机理奠定了理论基础。
分类: 核科学技术 >> 乏燃料后处理技术 提交时间: 2022-05-28
摘要: Nuclearmateriallicenseholdershoulddevelopanuclear materialaccountingmanagementsystemandachievethe closedbalance. Accordingtoregulationsrequirements, nuclear materialaccountancyimplementationisbasedonphysical inventoryandmaterialmeasurement. Generally, thespentfuel reprocessingplantoperatesuninterrupted, annualthroughput ofnuclearmaterialsishuge, differentmeasurementand analysistechniquesareconfiguredcombingthereprocessing process. Sotheclosedbalanceapproachofnuclearmaterials accountingisagreatchallenge. Inordertoimprovethe accuracyandreliabilityofnuclearmaterial, enhancethe timelinessofabnormaldetection, near-realtimeaccounting prospectofspentfuelreprocessingplantwasresearched. Inthis paper, thecrucialaspectaffectingtheclosedbalanceofnuclear materialswasdiscussed, thefactorssuchasthehead-end receiver-shipperdifference, theon-lineprocessmonitoring accuracy,theapplicabilityoftheinternationaltargetvalueof nuclearmaterialmeasurementuncertainty, andalsothe nuclearmaterialbalancemodelofreprocessingplants. As summarized,proposedsuggestionsandsolutionsfornuclear materialbalanceinspentfuelreprocessingplantwasput forwardontheendofthepaper.