Abstract RELAP5/SCDAP code has been improved by incorporating relevant chemical reaction models to evaluate the graphite oxidation behaviour in High Temperature Gas-cooled Reactor (HTGR). The developed code was validated against three individual experiments with different emphasis. It could be concluded that the developed Burn-off factor (M(B)) correlation showed a better performance on fitting the experimental data than the model proposed from the previous researches. Besides, the variation of the fractions of each gas species after the chemical reactions show a good agreement with the experimental results. Moreover, the temperature transient during the graphite oxidation was also reasonably reproduced with acceptable deviation. All in all, after the improvement, RELAP5/SCDAP code has a better capacity in evaluating the graphite behavior during the oxidation conditions, which improves its reliability on HTGR safety analysis.

中文翻译：

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RELAP5/SCDAP 代码在氧化过程中评估石墨行为的改进和验证

摘要 RELAP5/SCDAP 代码通过引入相关的化学反应模型来评估高温气冷堆（HTGR）中的石墨氧化行为。开发的代码针对三个不同重点的单独实验进行了验证。可以得出结论，开发的燃尽因子（M（B））相关性在拟合实验数据方面表现出比先前研究提出的模型更好的性能。此外，化学反应后各气体组分的变化与实验结果吻合良好。此外，石墨氧化过程中的温度瞬变也以可接受的偏差合理再现。总而言之，改进后，