球床高温气冷堆燃料颗粒中放射性核素的累积释放份额研究  

Study on cumulative fractional release of radionuclides in HTGR fuel particles

作　　者：杨辰[1,2] 房超[3,1,2] 张建[1,2] 曹建主[1,2] 

机构地区：[1]清华大学核能与新能源技术研究院,北京100084 [2]先进反应堆工程与安全教育部重点实验室,北京100084 [3]低维量子物理国家重点实验室,北京100084

出　　处：《物理学报》2014年第3期93-99,共7页Acta Physica Sinica

基　　金：低维量子物理国家重点实验室开放研究基金(批注号:KF201302);国家重大科技专项(批准号:ZX06901);国家自然科学基金(批准号:11104156)资助的课题~~

摘　　要：本文利用Fick扩散定律,给出经典方法和改进的两种累积释放份额的严格数学表达式,并分析与之相关的穿透时间的物理内涵,并分别用以上两种方法计算137Cs,90Sr,110mAg三种重要放射性核素通过SiC层扩散的累积释放份额.研究表明,传统的"穿透时间"概念并非放射性核素释放到SiC层外的时间,本文提出的改进方法可以更准确的描述放射性核素在燃料元件中的输运和扩散行为.During high-temperature gas refrigeration reactor （HTGR） operation, SiC in the fuel particles is the key structure for stopping radionuclides diffusing from the particles. Researchers put forward the concept of breakthrough time, which is the time of a large amount of radionuclides released through SiC from the particles, for the consideration of HTGR safety. However, this concept is not so accurate. This paper gives a strict expression of cumulative fractional release interims of classic and improved methods, and also analyses the relevant physical content of breakthrough time in the use of Fick＇s law of diffusion. By computing the cumulative fractional release of three kinds of important radiouuclides 1376s, 9~Sr and ll^mAg, and using the above two methods, we find that the traditional meaning of the physical quantity is not the time of radionuclides released from SiC. The improved method is more accurate for describing the release and transport condition of radionuclides in nuclear fuel particles.

关 键 词：高温气冷堆 核燃料颗粒 放射性核素 累积释放份额 

分 类 号：TL424[核科学技术—核技术及应用]