To support the regional strategy development of ASEAN NPSR using scientific research, Modified ART Mod 2 has been used to assess the fission product release from RPVs and SFPs independently. However, the Fukushima Accident suggested the possibility of simultaneous release from RPV and SFP which indicated the necessity of re-evaluation of the maximum source term. The objective was to assess the fission product behavior during a simultaneous failure in RPVs and SFPs of BWR type with Mark I containment design in multiple units using Modified ART Mod 2 in order to evaluate the maximum source term. The releases of cesium compounds in gas and aerosol forms from RPVs and SFPs of Units 1–3 of the Fukushima Daiichi NPP were selected as the case studies. It was found that the behavior of cesium compounds was mainly governed by the aerosols and atmospheric temperatures, which resulted in different characteristics in adsorption and thermophoresis. It also turned out that the simulation of a simultaneous release led to a smaller release than the summation of independent simulations of releases from RPV and SFP by 25%. This study helped estimate the maximum consequences in order to be able to effectively design the EPR for NPP accidents inside or outside the ASEAN region.

中文翻译：

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使用改进的ART Mod 2：福岛第一核电站事故模拟评估反应堆压力容器和乏燃料池同时失效期间的铯化合物行为

为了利用科学研究来支持东盟国家核安全计划的区域战略发展，已使用改良的ART Mod 2来独立评估RPV和SFP的裂变产物释放。但是，福岛事故表明有可能同时释放RPV和SFP，这表明有必要重新评估最大来源期限。目的是使用修改后的ART Mod 2评估带有Mark I密闭设计的BWR型RPV和SFP的BWR型RPV和SFP同时失效时的裂变产物行为，以评估最大源项。作为案例研究，选择了福岛第一核电站1至3号机组RPV和SFP中气体和气溶胶形式的铯化合物的释放。发现铯化合物的行为主要受气溶胶和大气温度支配，这导致吸附和热泳的特性不同。还发现，与RPV和SFP的独立发行模拟相比，同时发行的模拟导致的发行要小25％。这项研究有助于估算最大后果，以便能够有效地设计针对东盟地区内外的NPP事故的EPR。