基于小型中子发生器研究堆燃料组件^(235)U富集度的测量方法研究

Study on Measurement Method of ^(235)U Isotope Abundance of Fuel Assembly for Research Reactor Based on a Compact Neutron Generator

燃料组件中235U富集度测量方法普遍采用中子活化法和质谱法。由于中子活化法测量设备庞大和质谱法破坏样品的缺点,无法作为快速、便携测量燃料组件235U富集度的有效手段,不适于作为燃料组件管理和运输过程中铀同位素富集度的测量验证手段。为此,研发一种以小型中子发生器(14 MeV中子源)为激发源的快速、便携测量燃料组件235U富集度方法。依据特定裂变核素平均产额之比与235U富集度的近似线性相关性,成功地测量了235U富集度范围为10%~90%铀样品。

Neutron activation analysis and mass spectrometry are used as 235U isotope abundance of fuel assembly. Neutron activation analysis and mass spectrometry can＇t be used as an effective measurement means of the 235U Isotope Abundance of Fuel Assembly. Meanwhile they aren＇t also used as a verification mean of 235U isotopic abundance the fuel assembly management and transportation because of their shortcomings of large measurement equipment and sampling. So based on a compact neutron generator, a rapid and portable measurement method for 235U Isotope Abundance of Fuel Assembly is significant. According to the linear correlation relatin~ the ratio of average yield for the specific fissile nuclides to 235U Isotope Abundance, the samples whose ~U Isotope Abundance is 10%-90% are successfully measured. It provides the experimental basis for the verification of 235U Isotope Abundance of the fuel assembly for the research reactor.