中文摘要：

采用M ELCOR程序，对船用堆破口叠加全船断电事故进行建模计算，并对事故进程和源项释放进行了研究。计算结果表明：若应急电源无法投入，最终将导致压力容器下封头失效和舱底失效；所研究事故的惰性气体、碘释放量均在80％以上，且释放的I主要以CsI形式存在，滞留量大，气载量小。事故进展快慢取决于破口当量尺寸，但氢气的产量与堆芯温度、堆芯残余水量相关，与破口当量尺寸无直接关系，堆舱内发生氢爆可能性不大。本文计算结果可为应急抢修和应急决策提供技术支持。

英文摘要：

Using MELCOR code ,the combination of LOCA and blackout accident of ship reactor was modeled and calculated , and the accident process and source term release were researched . The results show that the accident leads to lower head of pressure vessel and bilge creep‐rupture finally without emergency power .The release fraction of inert gases and iodine are above 80% ,the main form of iodine is CsI with great deposit and less airborne fraction .The accident process is decided by the equiva‐lent diameter of break size .The production of H2 is decided by core temperature and water remaining in the core ,but has nothing to do with equivalent diameter of break size .T he probability of H2 detonation is unlikely to occur .T he results can provide tech‐nical support for emergency maintenance and emergency decision‐making .