蠕变诱发SGTR现象的模化及应用

Modelling and Application of Creep Induced SGTR Phenomenon

蠕变诱发蒸汽发生器传热管破裂(SGTR)现象是压水堆(PWR)核电厂严重事故进程中的一个典型现象。该现象的发生会导致放射性物质旁通核电厂安全壳,进而造成大量放射性物质释放。根据二级概率安全评价(PSA)的分析经验,该现象是引起放射性大量释放的典型现象。避免该现象的发生能够有效地降低大量放射性物质释放的可能性。因此,对于该现象的防治是核安全领域中的重要研究内容。构建了一套全新的蠕变诱发SGTR现象的模化方法。该方法能够根据特定电厂情况,计算出不同电厂条件下真实的蠕变诱发SGTR现象分支概率。利用该概率对核电厂发生大量放射性物质释放的频率进行重新计算,能得到更为准确的核电厂发生大量放射性释放的频率。进而提出了更加合理的核电厂风险见解,提高了核电厂的安全性。

The creep induced heat transfer pipe rupture(SGTR)of steam generator is a typical phenomenon in the course of serious accident in pressurized water reactor(PWR)nuclear power plant.This can occur when radioactive material passes through the containment vessel of a nuclear power plant,leading to the release of large amounts of radioactive material.According to the analysis experience of secondary probabilistic safety assessment(PSA),this phenomenon is a typical one that causes a large release of radioactivity.Avoiding this phenomenon can effectively reduce the possibility of a large amount of radioactive material being released.Hence,the prevention and control of this phenomenon is an important research content in the field of nuclear safety.A new set of modeling methods for creep induced SGTR phenomenon is established,which can calculate the real bifurcation probability of creep induced SGTR phenomenon under different power plant conditions according to specific power plant conditions.Using this probability to recalculate the frequency of massive radioactivity material release from nuclear power plant,more accurate frequency of massive radioactivity release from nuclear power plant can be obtained.Furthermore,a more reasonable view of the risk of nuclear power plant is put forward to improve the safety of nuclear power plant.