Code crosswalk of Fukushima-like simulations for Chinshan BWR/4 NPP using MELCOR2.1/SNAP, TRACE/SNAP, PCTRAN and MAAP5.03

After Fukushima Daiichi disaster, the safety analysis of severe accidents became one of the safety concerns in Taiwan. At the same time, Taiwan Power Company built up an event basis strategy called Ultimate Response Guideline (URG) to cope with the accident like Fukushima. The analysis of the effectiveness of URG also became the most popular issue in Taiwan. However, the beyond design basis accident was very complicate and combined with many different aspects. Although researchers in Taiwan did lots of analysis of URG using different codes with different aspects, the differences of codes in the severe accident analysis were not mention in any of those studies. Thus, a Fukushima-like accident of Chinshan Nuclear Power Plant (NPP) was done by four codes in this study: MELCOR2.1, TRACE, PCTRAN and MAAP5.03. All four codes shared the same boundary conditions in the accident simulations. The crosswalk of these codes was discussed in detail and showed the similarity and differences among these codes. Those similarity and differences can help the improvement of URG analysis and make that this kind of analysis has more reliability. Also, the application field of each code can be clearly distinguished and help the improvement of code use in future NPP safety analysis.