Abstract In view of the safety characteristics of the offshore floating nuclear plant (OFNP), an ocean condition available analysis code based on RELAP5 MOD3.3 is developed and the influences of single heaving, single rolling and combined motion of heaving and rolling on a OFNP were analyzed under station blackout accident (SBO). The results indicate that heaving motion accelerates the drop in the reactor pressure. The flow fluctuation caused by heaving motion promoted the derivation of residual heat after SBO; Rolling motion accelerates the declination of the reactor pressures and the coolant temperature after SBO, and also causes a large flow oscillation in pipes. The results also shows that the combined motion is more severe than these two single conditions. The parameters variation under the combined motion is more similar to that under its rolling condition. The residual heat can be removed effectively under all these conditions and the security will not be threatened.

中文翻译：

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SBO事故下单一和联合海洋运动对小型OFNP的影响

摘要 针对海上浮式核电站（OFNP）的安全特性，开发了基于RELAP5 MOD3.3的海况可用分析程序，研究了单垂、单横摇和纵摇联合运动对OFNP的影响。在车站停电事故（SBO）下进行分析。结果表明，升沉运动加速了反应器压力的下降。升沉运动引起的流量波动促进了SBO后余热的导出；滚动运动加速了 SBO 后反应堆压力和冷却剂温度的下降，同时也会引起管道内的大流量振荡。结果还表明，组合运动比这两种单一条件更严重。组合运动下的参数变化与其滚动条件下的参数变化更为相似。在所有这些条件下都可以有效地去除余热，并且不会威胁到安全。