【作者】 张佳；

【导师】 于涛；

【作者基本信息】 南华大学 ， 核科学与技术， 2016， 硕士

【摘要】 为了确保我国核能工业健康可持续的发展,提出了需要进一步发展乏燃料贮存技术。在满足我国核临界安全导则(HAD102/15)要求的前提下,提高乏燃料贮存安全性和贮存能力。本论文在将乏燃料假设为新燃料情况下对乏燃料贮存的临界安全开展以下研究:首先,研究乏燃料贮存格架材料与尺寸对临界安全的影响和优化AP1000乏燃料贮存池布置方案;其次,采用微扰理论,对AP1000乏燃料贮存格架不确定性进行计算和分析;最后,计算AP1000乏燃料池次临界度,并采用不确定度分析方法,评估AP1000乏燃料池的临界安全性能,验证计算结果并给出合理的安全裕量。研究表明:(1)选取Al-B4C复合材料作为乏燃料贮存格架中子吸收材料是合理的。根据系统工艺和临界安全要求,遵循HAD102/15和ANS57.2的规定,验证了乏燃料池的布置方案的可行性。(2)使用MCNP5对乏燃料池和贮存格架进行微扰计算与直接计算时如果扰动不会使特征函数有明显变化的问题时,使用MCNP5的微扰计算模块PERT虽然可以节约计算时间成本并且能够得到比较有效准确的结果,但是假设扰动大并且对系统特征函数有很大的改变时,其分析的结论和使用MCNP5直接方法所得到的结果存在比较大的偏差,则使用MCNP直接方法得到结果更为有效。(3)将AP1000乏燃料贮存池中的I区作为研究对象,保守地选取燃料组件最大富集度为5%,充分考虑乏燃料贮存池中水密度和贮存格架的工艺不确定性等多种因素对临界安全的影响,临界分析计算得到的最大的有效增殖系数Keff=0.94175,其低于临界分析计算准则要求的Keff值(建议不超过0.95)。所以,乏燃料池的临界安全是有保障的。以上结论将对乏燃料长期安全贮存以及提高核电厂乏燃料贮存能力具有重要的意义。更多还原

【Abstract】 Be ensure the healthy sustainable development of nuclear power industry in China. We put forward to further development the spent fuel storage technology.To satisfied the requirements the premise of nuclear criticality safety guideline,increasing the safety and storage capacity of the spent fuel storage.In this paper,in the case of spent fuel assumption into new fuel,carried on studied to critical security of spent fuel storage:Study the spent fuel storage framework material and size effects on the critical safety,Optimization layout scheme of AP1000 spent fuel storage pool.Secondly,according to perturbation theory, carried out perturbation uncertainty calculation and analysis to AP1000 spent fuel storage grid.At last,calculation subcriticality of AP1000 pools,and use uncertainty analysis methods,evaluating AP1000 spent fuel pool criticality safety performance,verify the calculated results and given reasonable safety allowance.The studies have shown that:(1) Select Al- B4 C composite material as the spent fuel storage framework neutron absorption material is reasonable.Based on the system process and critical safety requirements,following the HAD102/15 and ANS57.2 rules and confirm the layout of spent fuel pool.At the same time, initial fuel enrichment degree was5%,the Keff value of Pools is less than 0.95.Satisfy the requirement of the spent fuel pool criticality safety.(2) Due to the perturbation calculation problem is complexity.According to perturbation calculation and analysis,it is difficult to give the accuracy conclusion,if the disturbance won’t make the characteristic function hasobvious change,using the PERT perturbation calculation module of MCNP5 can save computation time and can get more accurate results effective.But the material change(cross section) is very large, its value and use MCNP5 direct method of numerical have larger deviation.(3) The AP1000 spent fuel storage pool in the area I is research object,we conservative select fuel assembly maximum enrichment degree is5%.Fully considering the spent fuel storage pool water density and grid storage uncertainty of technology influence on the critical safety,critical analysis of the calculated maximum effective multiplication factor Keff value is0.94175.The critical analysis of the below standards require that Keff value suggest no more than 0.95.Therefore, the spent fuel pool criticality safety is guaranteed.The above conclusions will provide spent fuel storage long-term security and improve the ability is of great importance.更多还原