为了准确分析核设施停机后周围空间的三维辐射剂量场分布情况,基于严格两步法(rigorous two step method,R2S)停堆剂量计算的方法,开发了基于蒙特卡罗输运计算程序MCNP5和燃耗计算程序ORGEN2.1耦合的三维停堆剂量计算程序MOCA,实现了中...为了准确分析核设施停机后周围空间的三维辐射剂量场分布情况,基于严格两步法(rigorous two step method,R2S)停堆剂量计算的方法,开发了基于蒙特卡罗输运计算程序MCNP5和燃耗计算程序ORGEN2.1耦合的三维停堆剂量计算程序MOCA,实现了中子输运计算、材料活化计算和光子剂量计算的自动耦合,并通过中子辐照例题与SuperMC程序进行对比验证,结果表明MOCA的计算结果与SuperMC计算的结果吻合较好,可以为核设施的运维检修以及退役的剂量率空间分布提供参考数据。展开更多
目的研究18F药物诊断时PET机房外的辐射剂量率。方法使用MCNP5计算0.551 Me Vγ光子经不同厚度混凝土屏蔽防护后的辐射剂量率。结果根据计算结果拟合的剂量率曲线符合指数衰减规律。结论 MCNP5程序计算18F药物诊断时的辐射剂量率是适用...目的研究18F药物诊断时PET机房外的辐射剂量率。方法使用MCNP5计算0.551 Me Vγ光子经不同厚度混凝土屏蔽防护后的辐射剂量率。结果根据计算结果拟合的剂量率曲线符合指数衰减规律。结论 MCNP5程序计算18F药物诊断时的辐射剂量率是适用的,18F辐射剂量率归一化衰减公式可应用于PET机房的辐射防护设计。展开更多
The components from spent fuel are discharged from the core and then stored in the framework of the spent fuel pool for cooling. However, it is of great significance to save the storage space of the spent fuel pool by...The components from spent fuel are discharged from the core and then stored in the framework of the spent fuel pool for cooling. However, it is of great significance to save the storage space of the spent fuel pool by shrinkage and shearing work to increase the spare fuel lattice number. In order to solve the problem of shrinkage and shearing work of spent fuel involving the problem of radioactive safety, the radioactive source item is calculated by ORIGEN2 program base on Unit 1 Ⅱ of Lingao Nuclear Power Plant(NPP), and the radiation dose rate of the related component shrinkage operation scene is simulated by the MCNP5 program. In addition, the effectiveness of shielding measures is discussed, and the maximum dose rate is within 0.35 μSv/h at the distance of 2.5 m from component center, and the maximum dose rate is almost 0 at the distance of 3.2 m from the component center. The intensity of the radiation dose produced by the related components is very low and can be neglected, which belong to the green area of NPP. The program calculation system from source term calculation to shielding calculation is established, and an engineering example is referenced, and its application and analysis are carried out. It provides a basis for radioactive safety analysis and evaluation for the shrinkage operation of spent fuel and makes the shrinkage technology of fuel-related components safer and more reliable.展开更多
文摘为了准确分析核设施停机后周围空间的三维辐射剂量场分布情况,基于严格两步法(rigorous two step method,R2S)停堆剂量计算的方法,开发了基于蒙特卡罗输运计算程序MCNP5和燃耗计算程序ORGEN2.1耦合的三维停堆剂量计算程序MOCA,实现了中子输运计算、材料活化计算和光子剂量计算的自动耦合,并通过中子辐照例题与SuperMC程序进行对比验证,结果表明MOCA的计算结果与SuperMC计算的结果吻合较好,可以为核设施的运维检修以及退役的剂量率空间分布提供参考数据。
文摘目的研究18F药物诊断时PET机房外的辐射剂量率。方法使用MCNP5计算0.551 Me Vγ光子经不同厚度混凝土屏蔽防护后的辐射剂量率。结果根据计算结果拟合的剂量率曲线符合指数衰减规律。结论 MCNP5程序计算18F药物诊断时的辐射剂量率是适用的,18F辐射剂量率归一化衰减公式可应用于PET机房的辐射防护设计。
基金Supported by the Project of Radiation Shielding Calculation Based on Unit 1 Ⅱ of Lingao Nuclear Power Plant of China
文摘The components from spent fuel are discharged from the core and then stored in the framework of the spent fuel pool for cooling. However, it is of great significance to save the storage space of the spent fuel pool by shrinkage and shearing work to increase the spare fuel lattice number. In order to solve the problem of shrinkage and shearing work of spent fuel involving the problem of radioactive safety, the radioactive source item is calculated by ORIGEN2 program base on Unit 1 Ⅱ of Lingao Nuclear Power Plant(NPP), and the radiation dose rate of the related component shrinkage operation scene is simulated by the MCNP5 program. In addition, the effectiveness of shielding measures is discussed, and the maximum dose rate is within 0.35 μSv/h at the distance of 2.5 m from component center, and the maximum dose rate is almost 0 at the distance of 3.2 m from the component center. The intensity of the radiation dose produced by the related components is very low and can be neglected, which belong to the green area of NPP. The program calculation system from source term calculation to shielding calculation is established, and an engineering example is referenced, and its application and analysis are carried out. It provides a basis for radioactive safety analysis and evaluation for the shrinkage operation of spent fuel and makes the shrinkage technology of fuel-related components safer and more reliable.
