钍铀燃料循环中钍核参数的积分中子学研究

For the evaluated nuclear data of Thorium in the Th-U fuel cycle, the accuracy is the key factor to determine the validaty of the reactor physics design. The reliability of thorium nuclear datas in Th-U fuel cycle must be validated by integral neutronic experiments, to improve the neutron availability and effective breeding of fuel in this type of cycle. Aimed at the above goal, in this study, many work are planned, including the neutronic parameters integral experiment relevant to Thorium nuclide, development of neutronic experimental technique, design and establishment of thorium sample and experimental mock-up, experiments on convertion rate of 232Th to 233U、fission rate of thorium、neutron spectra and so on. From these works, we can analyze the breeding of 233U nuclide, get the experimental data of neutronic integral parameters, validate the nuclear data of thorium in the evaluated nuclear libraries and obtain the reliability data. The works can also be reference for the planning new evaluation of libraries, and provide foundation for deeply neutronic study of the nuclides in Th-U cycle.

钍铀燃料循环中钍核素评价核数据是中子学设计计算中的关键点,其准确性决定了反应堆物理设计的有效性。钍核数据的可靠性需要通过积分中子学实验进行检验，以提高钍铀循环的中子经济性和燃料的有效增殖。本项目拟通过开展钍核参数的积分中子学实验研究，发展和改进相关积分中子学参量测量技术，设计和建立钍样品装置，开展232Th/233U转换率、钍裂变率、中子能谱等积分中子学实验研究，分析233U的增殖情况，获取系列积分中子学参量的实验数据，检验钍核参数，给出已有相关评价核数据库的可靠性分析结果，为核数据库的再评价提供参考，并为深入开展钍铀燃料循环相关核素的中子学研究打下技术基础。

钍铀燃料循环中钍核素评价核数据是中子学设计计算中的关键点，其准确性决定了反应堆物理设计的有效性。钍核数据的可靠性需要通过积分中子学实验进行检验，以提高钍铀循环的中子经济性和燃料的有效增殖。本项目通过开展钍核参数的积分中子学实验研究，发展和改进了钍反应率积分中子学参量测量技术，设计和建立了钍样品、氧化钍圆柱、组合体等钍样品装置，开展了232Th/233U转换率、钍裂变率、钍(n,2n)反应率、中子能谱等积分中子学实验研究，分析了233U的增殖情况，获取了系列积分中子学参量的实验数据，使用MCNP5程序结合主流数据库分析了实验数据和钍相关核参数，给出了分析结果。研究结果可为有关核数据库的再评价提供参考，并为深入开展钍铀燃料循环相关核素的中子学研究打下了技术基础。