横摇条件下海上小型堆完全丧失交流电事故分析

Safety Analysis of SMR on Total Loss of Alternative Power Condition under Rolling Condition

本文分析了横摇工况对海上小型堆完全丧失交流电事故的影响。研究结果表明,在发生完全丧失交流电事故时,通过一回路自然循环和PSHR系统带走堆芯衰变热;在横摇工况下,一回路自然循环流量发生周期性变化,变化周期与横摇周期相同;横摇频率越高、横摇幅值越大,一回路自然循环流量变化越剧烈。横摇条件下,PSHR系统投入时间比静止条件下的晚,横摇越剧烈,PSHR系统投入时间越晚。PSHR系统投入后,横摇运动强化了系统的换热,一回路降温速率比静止条件下快,横摇越剧烈,一回路降温速率越快。

In the present paper,the effects of rolling condition on the total loss of alternative power conditions are analyzed.The results show that,during the transient,the decay heat is removed by natural circulation of the primary loop and the PSHR system.Under the rolling condition,the primary natural circulation flow rate changes on a period of the rolling period.The larger the rolling frequency or amplitude,the flow rate fluctuation is more violent.The PSHR systems were started later than that under static condition.The more violent the rolling is,the later the PSHR is put into operation.The heat transfer is enhanced under the rolling condition,thus the decreasing rate of the RCS temperature is increased.The larger the rolling frequency or the amplitude is,the larger is the decreasing rate of the RCS temperature.