Intentional depressurization and cavity flooding are two important measures in current severe accident management guidelines (SAMGs). An extreme scenario of an extended station blackout (ESBO), when electric power is unavailable for more than 24 hours, actually occurred in the Fukushima Daiichi accident and attracted lots of attention. In an ESBO, the containment spray cannot be activated for condensation, and, thus, cavity flooding will generate a large amount of steam, which, ironically, overpressurizes the containment to failure before the reactor vessel is melted through. Therefore, consideration of these conflicting issues and the ways in which plants operate is crucial for strengthening the strategies outlined in SAMGs. In this paper, the effects of intentional depressurization and cavity flooding in an ESBO for a representative 900 MW second-generation pressurized water reactor (PWR) are simulated with MAAP4 code. Diverse scenarios with different starting times of depressurization and water injection are also compared to summarize the positive and negative impacts for accident mitigation. The phenomena associated with creep ruptures, hydrogen combustion, corium stratification, and cavity boiling are also analyzed in detail to strengthen our understanding of severe accident mechanisms. The results point out the facility limitations of second-generation PWRs which can improve existing SAMGs.
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2s39ORl
via IFTTT
Εγγραφή σε:
Σχόλια ανάρτησης (Atom)
Δημοφιλείς αναρτήσεις
-
Publication date: Available online 4 January 2018 Source: European Journal of Radiology Author(s): Peiyao Zhang, Jing Wang, Qin Xu, Zhen...
-
Related Articles Anatomic parameters of the sacral lamina for osteosynthesis in transverse sacral fractures. Surg Radiol Anat....
-
Medicine by Alexandros G. Sfakianakis,Anapafseos 5... Medicine by Alexandros G. Sfakianakis,Anapafseos 5... Heralding change: The evolution ...
-
Background Hyperthyroidism is associated with increased thrombotic risk. As contact system activation through formation of neutrophil extrac...
-
BACKGROUND AND PURPOSE: Dengue is a common arboviral disease, which uncommonly involves the brain. There has been a recent surge in dengu...
-
Abstract Purpose Investigate in patients with metastatic and/or irresectable colorectal cancer treated with systemic treatment with cape...
-
Publication date: January 2017 Source: The Journal of Emergency Medicine, Volume 52, Issue 1 Author(s): Patricia Michelle Troxell Klingen...
-
In rural Kenya, traditional and faith healers provide an alternative pathway to health care, including mental health care. However, not much...
-
2016-12-10T02-17-59Z Source: Indo American Journal of Pharmaceutical Research R. Santosh Kumar*, T. Naga Satya Yagnesh. Solid dispersio...
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου