CAJ | 학술논문

氢化锂（LiH ）以其低密度、高熔点、较高的H原子份额等良好的热物性，被用作空间核热推进反应堆的慢化剂和屏蔽材料。考虑到低能区LiH热中子数据的缺失使得数值模拟结果与实际相差很大，本文对LiH热化效应机理进行初步研究，基于第一性原理方法计算了LiH 的声子谱，采用GASKET 和NJOY程序建立LiH热散射律和散射矩阵的计算模型，制作成MCNP的ACE格式的LiH热中子截面数据库。对比文献结果和ZrH2热散射截面，分析差异的原因，采用Debye模型的抛物线效应修正了次级能量分布情况。该截面值可为下一步高温粒子球床堆物理建模提供必要的数据。
경화리（LiH ）이기저밀도、고용점、교고적H원자빈액등량호적열물성，피용작공간핵열추진반응퇴적만화제화병폐재료。고필도저능구LiH열중자수거적결실사득수치모의결과여실제상차흔대，본문대LiH열화효응궤리진행초보연구，기우제일성원리방법계산료LiH 적성자보，채용GASKET 화NJOY정서건립LiH열산사률화산사구진적계산모형，제작성MCNP적ACE격식적LiH열중자절면수거고。대비문헌결과화ZrH2열산사절면，분석차이적원인，채용Debye모형적포물선효응수정료차급능량분포정황。해절면치가위하일보고온입자구상퇴물리건모제공필요적수거。
LiH is designated as a promising moderator and shielding material because of its low density ,high melting point and large fraction of H atoms .However ,lack of the thermal neutron cross sections of LiH makes numerical calculation deviate from experi-mental data to some extent .In this paper ,the thermal kernel effect of LiH was studied , the phonon spectrum of LiH based on the first principle was calculated ,and the models of LiH thermal scattering law and matrix by GASKET and NJOY codes were construc-ted .The ACE format LiH thermal neutron cross sections for MCNP were generated . Comparison between thermal scattering cross section of ZrH2 and reference results was done ,and the secondary neutron spectra were modified by parabolic behavior of Debye model .These cross section could be used in the modeling of the nuclear propulsion particle bed reactor .