基于MELCOR与MCNP程序的安全壳剂量率计算方法

严重事故条件下,评估安全壳内的放射性剂量率水平对核电厂严重事故管理、应急响应等环节具有重要指导意义。本工作利用MELCOR程序模拟严重事故序列,计算不同核素组释放进入安全壳内的质量;利用ORIGEN2程序计算不同核素组的堆芯积存量及核素的γ源强;利用MCNP程序计算每组核素100%释放进入安全壳所产生的剂量率水平;最后根据拟合公式求解安全壳剂量率。中核核电运行管理有限公司30万千瓦机组安全壳剂量率的计算结果说明该方法切实可行。

Calculating Method of Containment Dose Rate Based on MELCOR and MCNP Codes

It is important to evaluate the containment dose rate under severe accident conditions for some aspects of a nuclear power plant, such as severe accident management and emergency response. In this work, the MELCOR code was used to simulate the sequence of severe accidents, calculate masses of radioactive fission products released to containment. The ORIGEN2 code was used to calculate the γ source intensity. The MCNP code was used to calculate the containment dose rate when each group of radioactive fission products was all released to containment. The containment dose rate was finally calculated by a fitting formula. This method was used in the 300 MW units of CNNP Nuclear Power Operations Management Co. Ltd and was proved to be available.