田湾核电站长周期换料大破口失水事故分析

田湾核电站拟采用长周期换料策略，堆芯设计的改变需对设计基准事故进行重新分析。本文对反应堆入口主管道大破口失水事故进行了计算分析，在保守的初始输入及计算假设的基础上，通过对轴向功率分布及应急堆芯冷却系统的保守性分析，得出基于燃料包壳温度的最保守的计算工况，并进行了计算。计算结果表明，实施长周期策略后，大破口失水事故仍可满足验收准则的要求，堆芯设计具有足够的安全裕量。

Large Break LOCA Analysis on Long Fuel Cycle for Tianwan Nuclear Power Station

The long fuel cycle will be implemented in Tianwan Nuclear Power Station, and the design basis accident needs to be re-analyzed since the change of core design. The large break LOCA was analyzed in the paper. Based on the input data and calculation assumption, the most conservative calculated case was obtained through the conservative analysis of the axial power distribution and the ECCS. It is shown that the accept criteria are satisfied in the large break LOCA on long fuel cycle, and the safety margin of the core design is large enough.