Open AccessSYSTEM DYNAMICS MODEL DEVELOPMENT BY ANALYZING CAUSES OF FUKUSHIMA DAIICHI NPP UNIT-1 ACCIDENT
Author(s) -
Muhammed Mufazzal Hossen,
Mahmud Hossain
Publication year - 2021
Publication title -
international journal of engineering applied science and technology
Language(s) - English
Resource type - Journals
ISSN - 2455-2143
DOI - 10.33564/ijeast.2021.v06i03.004
Subject(s) - environmental science , natural circulation , nuclear engineering , nuclear power plant , containment (computer programming) , radiological weapon , shutdown , accident management , engineering , computer science , nuclear physics , physics , medicine , radiology , programming language
Fukushima Daiichi NPP accident occurred onMarch 11, 2011. A system dynamics model is developed byanalyzing the chronological progression and causes of theFukushima Daiichi NPP unit-1 accident applying causeeffect relationship and qualitative causal loop andfeedback loop. The accident progression demonstrates thatthe safety system of the NPP could not function properly,resulting in the loss of core cooling and confinement ofradioactive materials functions, and a severe accident withhydrogen explosion occurred. The system dynamics modelshows that earthquake, tsunami induced flooding, designfailure of Tsunami height, loss of all AC power, loss of DCpower, loss of ultimate heat sink, failure of HPCI system,failure of IC system, design complexity of isolation valvesof IC and lack of training on IC operation, delayed waterinjection to reactor, delayed operation of containmentventing, lacking of compressed air, high reactor pressure,and harsh radiological condition are the causes of thissevere accident. High reactor pressure and harshradiological condition were produced during the accident,which positively boost accident progression bydemonstrating the effect of system dynamics. Theconservative design to protect power sources from naturalevents and the loss of all power for an extended periodmust be considered during future design of NPP.