摘要
压水堆燃料污垢除了可能引起堆芯轴向功率偏移异常(CIPS)和燃料包壳局部腐蚀(CILC)之外,还与一回路活化腐蚀产物及其形成的辐射场密切相关。不同的燃料污垢辐照程度会导致一回路活化腐蚀产物源项水平的差异。本文建立了通过特征比活度法确定燃料污垢辐照行为的分析模型,得到燃料污垢中的母子核数量比及54Mn/59Fe活度比与辐照时间的单调关系。通过分析得到,在测量数据充足的前提下,应建议优先使用54Mn/Fe核素进行辐照时间分析。对CPR1000机组的分析结果表明,通过54Mn/59Fe和58Co/Ni比值法得到燃料污垢在堆芯的辐照时间约为100天,且54Mn/59Fe方法更可靠。分析还得到停堆期间燃料污垢中Ni的释放速度比58Co释放更快。本文提供的燃料污垢辐照时间评价方法和结果可为燃料污垢及活化腐蚀产物模型提供基准,为运行电厂进行燃料污垢数据测量提供比对和参考,同时也为核电厂集体剂量优化提供一种思路。
The characteristics and behaviour of PWR fuel crud are not only closely related to the risks of CRUD-induced power shifts(CIPS)and CRUD-induced localized corrosion(CILC),but also related to the activated corrosion product activity and the plant radiation field build-up.Different irradiation rates of the fuel crud lead to different rates of formation of the corrosion product radionuclides.A model of fuel crud irradiation time based on specific activity method is established in this paper,and the monotone relationship between the irradiation time and the amount ratios of daughter nuclide and parent element as well as the 54Mn/59Fe activity ratio are obtained.The study in this paper show that the specific activity based on 54Mn/Fe is most reliable to analysze the irradiation time,provided there are enough measured data.Analysis of CPR1000 PWRs based on 54Mn/59Fe and 58Co/Ni indicate that the irradiation time is about 100 days,and the 54Mn/59 method is more reliable.It is also found out that the release of Ni is faster than that of 58Co in this paper.The valuation method and results of fuel crud irradiation behavior presented in this paper can provide a benchmark for the development of fuel crud and activity transport model as well as provide a comparison and reference for the fuel crud measurement in operating plants.In addition,it also provide a way of thinking for the collective dose optimization of PWRs.
作者
张晓茜
付鹏涛
ZHANG Xiaoqian;FU Pengtao(China Nuclear Power Technology Research Institute,Shenzhen of Guangdong Prov.518026,China)
出处
《核科学与工程》
CAS
CSCD
北大核心
2023年第3期510-516,共7页
Nuclear Science and Engineering
基金
国家自然科学基金针对堆芯氧化腐蚀产物材料-热工-中子行为的多物理耦合机理研究(U20B2011)
中国广核集团压水堆燃料运行零破损关键技术研究(No.3100121513)。
关键词
燃料污垢
腐蚀产物
集体剂量
特征比活度
辐照时间
Fuel crud
Corrosion product
Collective dose
Specific activity
Irradiation time
