基于GASFLOW的AP1000核电厂氢气风险分析

Containment Hydrogen Risk Analysis of AP1000 Nuclear Power Plant Based on GASFLOW

采用流体动力学软件GASFLOW对AP1000核电厂进行建模,在建模过程中,采用的直角坐标系的设置可以增加系统模型的准确性。采用MAAP计算的DVI(直接注入管线)双端断裂事故源项作为输入,研究不同隔间内氢气风险。结果显示:氢气在安全壳内形成分层现象,且壁面附近氢气浓度较高;除了破口隔间在不足60 s的时间内出现FA(Flame Acceleration)准则数大于1的情况外,其他隔间或其他时间段内均没有出现FA准则数大于1的情况。所有隔间内的DDT(Deflagration to Detonation Transition)准则数均小于1,可以认为所研究的事故工况下,均不存在燃爆风险。全局可燃气体云团的体积大约占了安全壳自由容积的1/30,安全壳内不可能发生全局快燃风险。

AP1000 nuclear power plant(NPP)model is developed with the computational fluid dynamic code GASFLOW.During the simulating,Cartesian coordinate system is used,for the AP1000 nuclear power plant,the usage of Cartesian coordinate system will enhance the veracity.The DVI double end guillotine break source from MAAP was used to study the hydrogen risk of different room.The results show that,the hydrogen in the containment will present layered structure,and the hydrogen density is higher near the cold wall.The FA number of the broken room is higher than 1 within 60 s,the other rooms’FA numbers and DDT numbers are all lower than 1.That means in the conditions we studied,all the room are without DDT risk.The global sigma cloud volume is less than 1/30 of the containment free volume,so the containment is without global FA.