非能动补水对AP1000乏燃料池局部硼稀释的影响分析

AP1000非能动电厂在事故后采用非能动补水的方式为乏燃料池提供冷却,同时临界安全分析要求乏池硼浓度高于最低允许硼浓度,以保证足够的次临界裕度。基于AP1000乏燃料池设计,采用CFD流体分析软件,使用多孔介质模型和组分输运模型模拟非硼化水源补水对燃料贮存区域的非均匀硼稀释影响。分析结果表明,燃料贮存区的局部硼浓度受到非硼化水源的稀释作用有所降低。在有效控制补水的前提下,局部硼浓度最低降至约2 140 ppm,高于允许的最低硼浓度值,不影响乏燃料临界安全。

AP1000 passive power plant uses passive water supply to provide cooling for the spent fuel pool after the accident,and the critical safety analysis requires that the boron concentration in the spent pool is higher than the minimum allowable boron concentration to ensure sufficient subcritical margin.Based on the design of AP1000 spent fuel pool,using CFD fluid analysis software,porous media model and component transport model are used to simulate the effect of non-boronized water supply on non-uniform boron dilution in fuel storage area.The results show that the local boron concentration in the fuel storage area is reduced by the dilution of non-boronized water sources.Under the premise of effective control of water replenishment,the local boron concentration is reduced to about 2 140 ppm,which is higher than the allowable minimum boron concentration,thereby does not affect the critical safety of spent fuel.