用于HFETR的材料辐照试验的新型装置

针对各种反应堆结构材料辐照样品的温度与中子注量要求，设计了一种适用于在高通量工程试验堆(HFETR)堆内进行材料辐照试验的新型辐照装置。本文简要介绍了该装置的结构特点、技术特点、辐照罐的设计以及测试系统与试验情况。目前，该装置已完成了多种材料的辐照试验，结果表明：装置具有温度调节范围宽(0-120℃)、系统调节能力强、安全可靠和出入反应堆方便等优点．完全能满足各种反应堆结构材料的高低温辐照试验要求。     

日本快堆开发新进展

日本政府已决定使用快堆取代轻水堆作为21世纪的主要核电系统。日本快堆开发计划要求在2025年以前建成一座示范堆，在2050年前建成第一座商业反应堆。日本政府已决定在2008年为下一代反应堆的研发工作投入130亿日元（1．09亿美元）。     

溶液堆内部事件概率安全分析框架研究

液体燃料反应堆（简称溶液堆）与传统固体燃料反应堆在安全设计和运行特性等方面存在重大差异,无法仅按照现有以确定论为核心的设计方法进行安全设计,必须在设计之初引入概率安全分析（PSA）技术。由于燃料形态、安全屏障及缓解系统等与固体燃料反应堆的差异,传统以堆芯损坏为核心的反应堆PSA技术无法直接适用于溶液堆。在调研国内外传统研究堆、溶液堆及乏燃料后处理厂相关要求及分析技术后,以我国正在研发的医用同位素试验堆为对象,提出了溶液堆PSA安全目标,并建立了PSA技术框架,为该类型反应堆PSA的开展和安全审查奠定基础。     

日本新反应堆的研究动向

【日本《原子能视野》2002年1月刊第18～22页报道】 日本从美国引进的轻水堆自1970～1971年陆续运营以来,逐渐谋求反应堆的大型化。目前,日本正着手开发电功率为1700 MW级的ABWRⅡ和APWR+型核电站反应堆。这些反应堆是对先前反应堆进行进一步改进与发展、是进一步谋求提高反应堆的经济性、安全性以及运行与自我维护性能的大型轻水堆。与此同时,日本还在研究开发能建在能源需求地附近的机动灵活的革新性小型反应堆、旨在有效利用资源的欠慢化能谱反应堆、旨在提高热效率的超临界压水堆、利用核热制造氢的高温气冷堆等。另外,在快中子增…     

美国新反应堆概念

【美国《核新闻》2003年9月刊报道】美国能源信息管理局(EIA)2003年7月份发表了一篇题为“新反应堆设计”的文章,归纳出目前美国现有的和到2030年有望启用的核反应堆设计,并列出EIA采用的概念选拔标准:在核管会(NRC)的认证或预认证计划内;在第四代反应堆国际论坛(GIF)的长期反应堆开发计划内。文章首先概要介绍了美国现役或已退役(如1974～1989年运行的圣符仑堡高温气冷堆)的反应堆类型,然后概述了在美国以外运行的商用反应堆(包括快中子堆、加压重水堆和气冷堆)设计。然后,文章论及潜在商用反应堆设计的新概念。文章说,美国未来10~20…     

俄罗斯核战略的关键：BN-800快中子增殖堆

【英国《国际核工程》2005年3月刊报道】俄罗斯BN-800快堆项目将满足21世纪核电面临的更加紧迫的新要求,包括防扩散要求。钠冷却快中子反应堆已经被选为实施《21世纪上半叶俄罗斯核电发展战略》的堆型。专家们关注的焦点目前主要集中在如何使这种堆型具有经济竞争力,并创建闭合燃料循环工业。目前正在乌拉尔斯维尔德洛夫斯克地区别洛雅尔斯克核电厂建造的新型BN-800反应堆将在完成上述两项任务中发挥重要作用。BN-800项目是俄罗斯开发的钠冷快堆的一种后续堆型,其开发基础是前后三代钠冷快堆的设计和运行经验。BN-800主要基于在以前的BN…     

研究堆低压电气贯穿件导体组件的研制

本文介绍了一种用于各种实验研究堆反应堆厂房内、外电缆连接的新型灌封组件式低压电气贯穿件.该贯穿件采取模块结构,便于拆卸和更换.导体组件自身的孔道密封采用阻燃型环氧树脂灌封实现,与端板孔道之间的密封由"O"型橡胶圈来保证,已通过气密性和电气性能型式试验的验证,满足实验研究堆工程要求.     

研究堆

【澳大利亚铀信息中心网站2002年8月报道】 世界上有许多核反应堆被用于研究和培训、材料试验或生产医用和工业用放射性同位素。这些堆比动力堆或推进船用的反应堆要小得多,而且许多位于大学校园里。目前世界上56个国家共有283个运行中的研究堆。 研究堆一般不用于发电,其主要目的是为研究或其它用途提供中子源。它们的输出(中子束)依用途不同而各据特点。其功率用兆瓦(或千瓦)热(MWt)表示(在这里,只简单地用MW或kW表示)。大部分研究堆的功率最高为100 MW,而典型的动力堆为3000 MW(即1000 MWe)。实际上全世界283个研究堆的总功率只比3…     

高温气冷堆主氦风机惰转特性研究

高温气冷堆主氦风机与压水堆主泵一样,均为反应堆一回路的关键设备.在反应堆正常工况下,两者具有相同的功能要求,但在事故工况时,因反应堆的运行特性不同,其功能要求各异.目前,对压水堆主泵的惰转特性已有大量的实验研究和实际运行结果,但有关主氦风机惰转特性的实验研究与理论研究还很缺乏.本文结合风机的气动特性与高温气冷堆一回路的阻力特性,从理论上研究高温气冷堆主氦风机的惰转特性,建立主氦风机惰转时的流量与转速的预测公式,并给出其数值预测结果,为高温气冷堆设计的初步安全分析提供依据.     

200MW常压采暖供热堆设计研究

介绍了２００ＭＷ常压采暖供热堆的方案设计及其与加热供热堆的比较，这种反应堆堆芯放在一个大而深的水池之中，利用水的静压力提高堆芯出口的温度，其供热水温可以满足集中供热系统的要求，而反应堆却工作在常压之下。与加压供热堆相比具有结构简单，固有安全，投资低，供热成本低以及在我国容易实施的特点。     

研究型反应堆防范恐怖袭击的对策

当今恐怖组织的特点表现为：掌握高技术、有充足的资源、前期准备充分、有坚定的自杀决心。研究型核反应堆的实体保卫与核电站相比,硬件和软件都相对薄弱,加之选址在人口稠密的城市周边,容易成为恐怖袭击的对象。本文分析了国内外研究堆的特点,讨论如何加强研究堆的安全管理和实体保卫措施。     

数值反应堆的研究现状与发展建议

数值反应堆技术是基于多物理紧耦合的高精度、高分辨率、高置信度的高保真数值模拟技术,其目的是实现核反应堆内物理现象的精确数值呈现和分析,大幅度提高核反应堆的设计能力和安全运行能力,用数值技术驱动核能技术的快速发展。本文总结了国内外数值反应堆技术的研究现状,提出了数值反应堆技术的发展建议。     

聚变-裂变混合能源堆一维计算模型燃耗分析

聚变-裂变混合能源堆包括聚变中子源和以天然铀为燃料、水为冷却剂的次临界包层,主要目标是生产电力。利用输运燃耗耦合程序系统MCORGS计算了混合能源堆一维模型的燃耗,给出了中子有效增殖因数k_eff、能量放大倍数M、氚增殖比TBR等物理量随时间的变化。通过分析能谱和重要核素随燃耗时间的变化,说明混合能源堆与核燃料增殖、核废料嬗变混合堆的不同特点。本文给出的结果可作为混合堆中子输运、燃耗分析程序校验的参考数据,为混合堆概念研究提供了基础数据。     

论解决核电安全问题的途径

从现有水冷反应堆核电厂存在堆芯熔化危险这一安全问题的焦点出发,分析了改进型反应堆AP-600、SIR、非能动安全反应堆PIUS和具有固有安全的模块高温气冷堆MHTGR等的安全特性.按照下一代水冷反应堆的设计要求和用户要求,提出了解决水堆核电厂安全问题的新概念——自安全铀氢锆反应堆,该堆型可能成为世界水堆核电发展的一个方问。中国核动力研究设计院正在探讨这种堆型。     

Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation’s energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.     

基于MCNP和ORIGEN的熔盐快堆燃耗分析计算

熔盐堆是6种第4代先进核能系统中唯一使用液态燃料设计的反应堆型,其堆芯一回路中循环流动的熔盐既是燃料,也是冷却剂。这一特征在省去燃料元件加工制造步骤的同时,也使得熔盐堆能进行在线处理和在线添料的操作。因此,传统固态反应堆燃耗分析程序不再适用于熔盐堆。本文以熔盐快堆(MSFR)为分析对象,基于物理分析程序MCORE(MCNP+ORIGEN),将上述熔盐堆特点考虑进去,开发出能进行熔盐堆燃耗分析的MCORE-MS。初步分析表明,233 U-started模式下,熔盐在线处理可有效降低堆芯熔盐中裂变产物的含量,提高中子经济性。MSFR运行过程中能够一直保持负的温度反应性系数。     

Economic viability of small to medium-sized reactors deployed in future European energy markets

Future plans for energy production in the European Union as well as other locations call for a high penetration of renewable technologies (20% by 2020, and higher after 2020). The remaining energy requirements will be met by fossil fuels and nuclear energy. Smaller, less-capital intensive nuclear reactors are emerging as an alternative to fossil fuel and large nuclear systems. Approximately 50 small (<300 MWe) to medium-sized (<700 MWe) reactors (SMRs) concepts are being pursued for use in electricity and cogeneration (combined heat and power) markets. However, many of the SMRs are at the early design stage and full data needed for economic analysis or market assessment is not yet available. Therefore, the purpose of this study is to develop “target cost” estimates for reactors deployed in a range of competitive market situations (electricity prices ranging from 45-150 €/MWh). Parametric analysis was used to develop a cost breakdown for reactors that can compete against future natural gas and coal (with/without carbon capture) and large nuclear systems. Sensitivity analysis was performed to understand the impacts on competitiveness from key cost variables. This study suggests that SMRs may effectively compete in future electricity markets if their capital costs are controlled, favorable financing is obtained, and reactor capacity factors match those of current light water reactors. This methodology can be extended to cogeneration markets supporting a range of process heat applications.     

Preliminary study on feasibility of large and small water cooled thorium breeder reactor in equilibrium states

Fuel breeding is one of the essential performances for a self-sustaining reactor system which can maintains the fuel sustainability while the reactor produces energy and consumes the fissile materials during operation. Thorium cycle shows some advantageous on higher breeding characteristics in thermal neutron spectrum region as shown in the Shippingport reactor and molten salt breeder reactor (MSBR) project. In the present study, the feasibility of large and small water cooled thorium breeder reactors is investigated under equilibrium conditions where the reactors are fueled by ²³³U–Th oxide and they adopts light water coolant as moderator. The key properties such as required enrichment, breeding capability, and initial fissile inventory are evaluated. The conversion ratio and fissile inventory ratio (FIR) are used for evaluating breeding performance. The results show the feasibility of breeding for small and large reactors. The breeding performance increases with increasing power output and lower power density. The small reactor may achieve the breeding condition when the fuel pellets' power density of about 22.5 W/cm³ and burnup of about 20 GWd/t.     

热管反应堆多物理耦合平台初步研究

为实现高精度、高置信度的核能系统先进数值模拟技术,探究核能系统内部真实的物理过程,本文开发了中子物理-固体导热-应力分析的三维高精度核热固多物理耦合计算平台MPCH,可开展核反应堆的中子输运、热扩散和热膨胀的多物理耦合计算。该程序基于Picard迭代的外耦合框架,整合了开源蒙特卡罗程序OpenMC、有限元程序Nektar++和SfePy。本文以新型空间热管反应堆KRUSTY为对象,在核热固耦合的计算框架下对其进行计算分析。多物理耦合计算结果表明,该耦合平台能够有效预测KRUSTY反应堆的有效增殖因子变化、功率分布、温度分布及热膨胀现象;在4 kW的堆芯热功率下,全堆局部温差为21.6K,热应力导致的形变率为2.47%,核热固耦合的作用会使堆芯的温度分布更加均匀。该多物理耦合计算程序的设计对新堆设计、研发和校核具有重要作用。      

Application of candle burnup strategy for future nuclear energy utilization

The CANDLE burnup strategy is a new reactor burnup concept, where the distributions of fuel nuclide densities, neutron flux, and power density move with the same constant speed along the core axis from bottom to top (or from top to bottom) of the core and without any change in their shapes. Therefore, any burnup control mechanisms are not required, and reactor characteristics do not change along burnup. The reactor is simple and safe. If this burnup scheme is applied to some neutron rich fast reactors, either natural or depleted uranium can be utilized as fresh fuel after second core and the burnup of discharged fuel is about 40%. It means about 40% of natural or depleted uranium can be utilized without either enrichment or reprocessing.

In the ideal nuclear energy utilization system, the radioactive toxicity in the environment should remain or decrease after the utilization. This requirement is very severe and difficult to be satisfied. It may take too much time for its realization. The CANDLE burnup may substitute this period. Though it is a once-through fuel cycle, the discharged fuel burnup is about ten times of the present value for light water reactors. The space necessary for final disposal can be drastically reduced. However, in order to realize such a high burnup of discharged fuels some innovative technologies should be developed. Either new material standing still for such a high burnup or intermediate recladding will be required. Especially new fuel development will take a lot of time. For the time being a small reactor with CANDLE burnup may be a good option for nuclear power generation. Even this kind of reactor requires some innovative technologies and a long period for their developments. For the first stage of CANDLE burnup the prismatic fuel high-temperature gas cooled reactor is preferable. Since the design of this reactor fits to the CANDLE burnup very well, only a little time is required for its research and development.