Current Status of Core Degradation and Melt Progression in Severe LWR Accidents

TEPCO announced that the safety relief valves of the Fukushima Daiichi NPP Unit 1 were never manually opened during the accident due to the shortage of DC power. However, the measured reactor pressure was about 1MPa at 2:43 of March 12. At that moment the core damage must already start due to almost no core injection for nearly 11 hours while the reactor vessel bottom head must not fail according to the severe accident analyses so far. Such unanticipated depressurization might accelerate the core "uncovery" and also prevent early containment failure caused by the direct containment heating. The authors modeled the creep failures of the stainless steel guide tubes of the source range monitor (SRM) in the reactor core and the main steam line. Based on such failure models, the possible depressurization mechanism of the Unit 1 and related phenomena were estimated using a severe accident analysis code SAMPSON. The estimated scenario by this study is that the creep failures of the SRM dry tubes failed first and caused the leakage from the core to the containment while the direct cause of the depressurization is the creep failure of the main steam line after the start of core damage.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

hi@scite.ai

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Current Status of Core Degradation and Melt Progression in Severe LWR Accidents

Cited by 3 publications

References 23 publications

Current knowledge on core degradation phenomena, a review

Current knowledge on core degradation phenomena, a review

The impact of assessing lower head integrity on boiling water reactor probabilistic risk assessments

Estimation of the Depressurization Process of Fukushima Daiichi NPP Unit 1

Contact Info

Product

Resources

About