共查询到19条相似文献,搜索用时 218 毫秒
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针对小型钠冷快堆模块化设计需求,提出了一种利用安全壳内空气自然循环将堆芯余热导入大气最终热阱的非能动余热排出系统方案。通过理论计算并结合系统分析程序RELAP5,对非能动余热排出系统进行建模,分析系统方案的可行性。结果显示:保守假设条件下,在钠装载量为2000 kg工况时,非能动余热排出系统功率在16.88 kW以上可保证堆芯燃料温度不超过安全限值。RELAP5计算结果表明,本文提出的非能动余热排出系统方案冷却功率大于所需最小功率,能满足小型钠冷快堆设计需求。 相似文献
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钠冷快堆是第4代核反应堆的主力堆型,瞬态热工水力及安全特性是其设计研发和安全评审的重要工作,需要专用的分析工具。本文基于模块化建模思想,建立了钠冷快堆系统关键部件的热工水力模型和辅助模型,采用具有高稳定性和自动变步长能力的Gear算法,开发了钠冷快堆瞬态热工水力及安全分析软件THACS,并通过了国际基准题EBR-Ⅱ的有保护失流事故实验SHRT-17的初步验证。结果表明,THACS程序能较好模拟此实验的瞬态过程,具备钠冷快堆瞬态热工水力及安全分析的能力,可为我国钠冷快堆研发提供支持。 相似文献
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【本刊2012年5月综合报道】除积极开展大型钠冷快堆的研发之外,俄罗斯还在大力推动新一代小型模块堆的研发和建设工作。2012年2月,俄罗斯国家原子能集团(Rosatom)宣布,已经完成了SVBR-100设计文件的起草工作。SVBR-100是一种小型模块化快堆,采用铅-铋合金冷却剂,热功率为280MWt,电功率为101MWe,设计运行寿期60年,换料周期7~8年。在这种设计中,蒸汽发生器和堆芯均位于铅-铋冷却剂池内(池温为340~490℃),因此被称为一体化设计。SVBR-100模块直径4.5米、高7.86米,将在工厂进行装配(周期估计为42个月),然后运抵核电站厂区,置入一个用于提供非能动冷却和辐射防护功能的水箱内。该堆使用铀-235丰度为16.3%的二氧化铀燃料,也可使 相似文献
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《中国原子能科学研究院年报(英文版)》2018,(0)
正在我国小型钠冷快堆(SSFR)的屏蔽设计中,参照目前已建或在建的钠冷快堆的屏蔽设计,堆侧采用碳化硼和不锈钢屏蔽,厚度为101cm。但SSFR是具有可移动性的反应堆系统,屏蔽空间有限。目前的屏蔽设计方案中占用的屏蔽空间较大,需优化屏蔽设计,减小SSFR堆侧屏蔽的厚 相似文献
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本文概述钠冷快堆的载热系统,综合快堆冷却系统的设计原则和方法,提供某些重要数据。对钠冷快堆一次钠回路系统的“池式”和“管式”布置方案作了分析比较,认为实验快堆采用“管式”双回路载热系统比较合适。 相似文献
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钠空泡反应性效应是钠冷快堆核设计和安全分析的重要内容。本文基于多群节块扩散法,采用微扰理论推导出钠空泡反应性的计算方法,对1 000 MWe钠冷快堆MOX燃料堆芯的总钠空泡反应性、空间分布、物理分项进行了计算。结果表明,钠空泡反应性主要来源于中子泄漏的增加和能谱的硬化,两者一正一负,且空间分布规律相反,导致钠空泡反应性具有强烈的空间依赖性;对于所计算的MOX燃料堆芯钠空泡反应性高达3 $左右。计算和分析结果阐明了钠空泡反应性的产生机理和分布规律,可为低钠空泡的设计提供参考。 相似文献
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Nobuyuki Ueda Izumi Kinoshita Akio Minato Shigeo Kasai Tsugio Yokoyama Shigeki Maruyama 《Progress in Nuclear Energy》2005,47(1-4):222-230
CRIEPI and Toshiba Corp. have been exploring to realize a small-sized nuclear reactor for the needs of dispersed energy source and multi-purpose reactor. A conceptual design of 4S (Super-Safe, Small and Simple) reactor is proposed to meet the following design requirements: (1) All temperature feedback reactivity coefficients including whole core sodium void reactivity are negative; (2) The core integrity is secured against all anticipated transient without reactor scram; (3) No emergency power nor active mitigating system is required; (4) The reactivity core lifetime is more than 10 years. The 4S reactor is a metallic fueled sodium cooled fast reactor. A target of an electrical output is 10–50 MW. A remarkable feature of 4S is that its reactivity is not controlled by neutron absorber rods but by neutron reflectors to cope with a long core lifetime and a negative coolant void reactivity.
This study includes a design consideration of 4S. Design discussions are mainly focused on various core designs to meet above requirements. A tall core active height is adopted to gain long core lifetime. An averaged fuel burn-up is tried to be increased up to 100 GWd/ton from a point of economic view. The reference 4S designs are 10 MWe (30 years core lifetime) and 50 MWe (10 years core lifetime). 相似文献
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Takafumi Aoyama Takashi Sekine Shigetaka Maeda Akihiro Yoshida Yukimoto Maeda Soju Suzuki Toshikazu Takeda 《Nuclear Engineering and Design》2007,237(4):353-368
Many changes were made in the recent upgrade of the experimental fast reactor JOYO to the MK-III design. The core changes which were made to achieve a four-fold increase in irradiation capacity includes the introduction of a second enrichment zone, an increase in core radius and a decrease in core height. Performance tests done at low power, during the rise to power, and at full power, which focus on the neutronics characteristics, are presented. These tests include the nuclear instrumentation system response, the approach to criticality and excess reactivity evaluation, control rod worth calibrations, isothermal temperature coefficient evaluation, the calibration of the nuclear instrumentation system with reactor thermal power, and the burn-up reactivity coefficient. The measurements and comparisons with calculated predictions are shown. The design predictions are consistent with the performance test results, and all technical safety specifications are satisfied. The JOYO MK-III core will provide enhanced irradiation testing capability, as well as serve as a test bed for improving fast reactor operation, performance, and safety. Through the performance test evaluation, the core characteristics of a small size sodium cooled fast reactor with a hard neutron spectrum are clarified. 相似文献
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钠冷快堆是第4代反应堆中的优选堆型,具有安全性高的特点。池式钠冷快堆的双层容器泄漏会导致一回路钠泄漏并发生严重事故。本文采用概率安全分析方法分析池式钠冷快堆双层容器泄漏事故,包括事故的确定论分析及放射性释放路径分析以及池式钠冷快堆双层容器泄漏的事故序列及定量化。结果表明,池式钠冷快堆双层容器泄漏事故后正常通风开启情况下可能发生大量放射性释放。双层容器泄漏导致的大量放射性释放频率为1.07×10-11(堆•年)-1,双层容器泄漏事故中大量放射性释放占比为0.1%。 相似文献
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The effects of the cell configuration on core performance for a liquid sodium cooled MOX fuel type fast reactor and a PWR type thermal reactor are investigated. In this study our equilibrium cell iterative calculation system (ECICS) are used in order to obtain consistent neutron spectra, one-group constants and nuclide number densities at the nuclear equilibrium state. The fuel pellet diameter and the pin pitch are changed to evaluate their core characteristics. The distinction of reactors at the equilibrium state appears clearly by means of the change in the cell geometrical design. 相似文献
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After a brief survey about the history and the present status of liquid metal cooled fast reactors the paper explains the specific properties of liquid sodium and the principal layout of sodium-cooled fast reactor plants. The most important mechanical-structural requirements and problems are broken down into fields of sodium containment, core structure, and special mechanisms to be operated in sodium and the cover gas atmosphere. 相似文献
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This paper investigates the feasibility of designing a flexible fast breeder reactor from the view of neutronics. It requires that the variable breeding ratio can be achieved in operating a fast reactor without significant changes of the core, including the minimum change of fuel assembly design, the minimum change of the core configuration and the same control system arrangement in the core. The sodium cooled fast reactor is investigated. Two difficulties are overcome: (1) the different excess reactivity is well controlled for different cores, especially for the one with small breeding ratio; (2) the maximum linear power density is well controlled while the breeding ratio changes. The optimizations are done to meet the requirements. The U–Pu–Zr alloy is applied to enhance the breeding. The enrichment-zoning technique with unfixed blanket assembly loading position is searched to get acceptable power distributions when the breeding ratio changes. And the control system is designed redundantly to fulfill the control needs. Then, the achieved breeding ratio can be adjusted from 1.1 to 1.4. The reactivity coefficients, temperature distributions and preliminary safety performances are evaluated to investigate the feasibility of the new concept. All the results show that it is feasible to develop the fast reactor with flexible breeding ratios, although it still highly relies on the advancement of the coolant flow control technology. 相似文献