CAJ | 학술논문

确定反应堆内的中子源强对反应堆物理启动、临界实验和无源启动等活动的安全非常重要。本工作结合实际情况，通过分析轻水反应堆停堆后堆内中子源的种类及来源，确定堆内中子源主要由以下4部分组成：自发裂变中子源、（α，n）中子源、初级中子源和次级中子源。对这4种中子源的计算方法、原理进行研究，建立了数学计算模型，在计算模型中成功引入瞬跳近似和常源近似，提高了计算效率，在此基础上开发出可计算反应堆停堆后任意指定时刻堆内中子源强的程序包。通过例题计算表明，该程序对4种中子源的计算结果符合均很好，总中子源源强计算结果为5.60×106 s-1，计算误差为4％，该程序已经通过验证并投入实际使用。
학정반응퇴내적중자원강대반응퇴물리계동、림계실험화무원계동등활동적안전비상중요。본공작결합실제정황，통과분석경수반응퇴정퇴후퇴내중자원적충류급래원，학정퇴내중자원주요유이하4부분조성：자발렬변중자원、（α，n）중자원、초급중자원화차급중자원。대저4충중자원적계산방법、원리진행연구，건립료수학계산모형，재계산모형중성공인입순도근사화상원근사，제고료계산효솔，재차기출상개발출가계산반응퇴정퇴후임의지정시각퇴내중자원강적정서포。통과례제계산표명，해정서대4충중자원적계산결과부합균흔호，총중자원원강계산결과위5.60×106 s-1，계산오차위4％，해정서이경통과험증병투입실제사용。
T he confirmation of reactor neutron source is very important to the safety during reactor start-up ,critical experiment and reactor start-up without neutron source . By analyzing origins of neutron sources in light water reactors after shutting down ,it was made sure that the neutron sources in reactor core were mainly composed by the following four parts :spontaneous fission neutron source , (α, n ) neutron source , primary neutron source and secondary neutron source . T he calculation methods and principles of these four kinds of neutron sources were studied .A calculation model was built , and in which simplification measures were deduced to improve calculation efficiency .Based on this ,a computer code was developed to calculate the intensity of neutron source at any specified time after the reactor was shut down .Comparing with the reference examples ,the calculation results of the code coincide with the examples with a deviation no more than 4% . This neutron source calculation code has been validated and delivered to users .