基于R2S方法的反应堆结构材料活化剂量计算研究

反应堆结构材料在堆芯中子辐照下由于中子活化反应而产生大量的放射性核素，其衰变光子是反应堆停堆检修、换料、退役过程中工作人员职业照射剂量的重要来源。本文基于严格两步法（R2S），研究了反应堆结构材料栅元活化计算方法，并基于蒙卡粒子输运程序（MCNP）与点活化计算程序（ORIGEN）建立了反应堆结构材料活化剂量计算软件（MOCA）。通过开发功能接口与数据接口程序实现输运程序与活化计算程序的自动耦合，进而实现“中子输运-活化分析-剂量计算”全自动耦合分析。利用M5包壳活化计算模型、不锈钢活化计算模型和NUREG/CR-6115压水堆模型对MOCA进行基准验证，证明了MOCA的正确性与可靠性。 

Study on Activation-Induced Dose Calculation of Reactor Structural Materials

Numerous radioactive nuclides are produced from the neutron activation reaction of reactor structural materials under the core neutron irradiation. The decay photon from activated reactor structural materials is an important source of occupational exposure dose for workers during reactor shutdown & maintenance, refueling or decommissioning. This paper studies the cell activation calculation method for reactor structural materials based on Rigorous two step (R2S) method, and develops a reactor structural material activation dose calculation program, MOCA, based on the Monte Carlo particle transport code MCNP and point activation calculation code ORIGEN. Then, this study develops the functional interface and data interface codes to realize the automatic coupling of the transport code and activation calculation code thus to realize fully automated “neutron transport-activation analysis - dose calculation” coupled analysis. Finally, the M5 fuel cladding activation calculation model, stainless steel activation calculation model and NUREG/CR-6115 PWR model are used to perform benchmark verification of the MOCA, which proves that the MOCA is adequate and reliable.