Severe Accident Simulation of the Laguna Verde Nuclear Power Plant

Table 1

Main sequence of events in a LOCA without cooling effects.

Time (seconds)	Event
0.0	The reactor operates to power uprate conditions (2027 MWt).
30.0	Loss of external power, loss of coolant in a recirculation loop, closing of the turbine control valves, and trip of the reactor and recirculation pumps.
34.3	Low level in the reactor vessel (L2), before high pressure occurs in the drywell. The emergency core cooling systems (HPCS* and RCIC*) are active without injecting. Starts closing insolation valves (MSIV*).
37.4	Low-low level (L1) is reached.
40.0	Level in the BAF*.
200.0	Level below the core support plate.
324.0	Hydrogen generation starts.
370.0	Maximum temperature at the core surface of 1073 K.
458.0	Core damage stage starts with release of fission products.; Maximum Temperature at the core surface of 1185 K.
936.0	Control rod damage starts; Maximum temperature at control rod of 2136 K.
1800.0	Core damage de 19%.
3600.0	Core damage of 78%.

*HPCS: high pressure core spray system; RCIC: reactor core isolation cooling; MISV: main steam insolation valves; BAF: bottom of active fuel.