DHR-200池式低温供热堆SBO-ATWS事故及自然循环能力分析

Analysis of SBO-ATWS Accident and Natural Circulation Capacity of DHR-200 Pool Type Low Temperature Heating Reactor

DHR-200池式低温供热堆(简称DHR-200池式堆)设计有自然循环瓣阀,为检验其安全性,选取典型的全厂断电叠加紧急停堆系统失效(SBO-ATWS)事故,使用RELAP5程序对其热工水力参数瞬态特性及其自然循环能力进行分析。结果表明,DHR-200池式堆具有很好的负温度反应性反馈效应,即SBO-ATWS事故后,由于燃料和冷却剂温度升高,引入负反应性,可使反应堆实现热停堆;事故后,通过非能动方式开启自然循环瓣阀,可建立稳定的自然循环,将堆芯衰变热导出至堆水池内,验证了DHR-200池式堆的固有安全性。

DHR-200 Pool Type Low Temperature Heating Reactor(DHR-200)was designed with natural circulation flap valve.In order to examine the safety of the DHR-200,the RELAP5 code was used to analyze the transient thermal-hydraulic characteristics and the natural circulation capacity under the station blackout anticipated transient without scram(SBO-ATWS).The results show that DHR-200 has enough negative temperature reactivity feedback effect.With the rising of the temperatures of the fuel and the coolant,finally the reactor can be shut down by the effect of the negative temperature reactivity feedback effect.After the accident,the natural circulation flap valve will be opened by passive means to establish a stable natural circulation,and then the residual heat of the core can be removed to pool of the reactor.Therefore,it is demonstrated that the DHR-200 has good inherent safety features.