Loss of offsite power accident analysis in a VVER-1000/V446 nuclear power plant

The aim of this study is to pres ent a thermo-hy drau lic anal y sis of the loss of offsite power ac ci dent in VVER-1000/V446 nu clear power plant us ing the RELAP5 code. Loss of offsite power ac ci dent would lead to the un avail abil ity of ma jor ac tive safety sys tems, and that the safety cri te ria en sur ing a se cure op er a tion of the nu clear power plant would be vi o lated, re sult ing in core heat-up with pos si ble core deg ra da tion. There fore, the anal y sis and in ves ti ga tion of the plant, dur ing this ac ci dent, is very im por tant. For this pur pose, dif fer ent be hav iors of ma jor com po nents in the pri mary and the sec ond ary sides of the re ac tor cool ant sys tem are stud ied. In this pa per, the re ac tor is sim u lated by us ing RELAP5 sys tem code. The re sults show a rea son able agree ment with the de vel oped model and also with the Bushehr nu clear power plant fi nal safety anal y sis re ports.