Simulation of the Lower Head Boiling Water Reactor Vessel in a Severe Accident

Table 2

Conditions of in-core molten pool during the accident sequence.

Parameter	Time (s)
	1,800	1,900	2,000	2,100	2,200	2,300	2,500	2,590
Effective radius of molten pool (m)	0.84	0.95	1.04	1.12	1.12	1.22	0.82	0.82
Temperature of molten pool (K)	2,870	2,872	2,897	2,919	3,003	2,999	2852	2858
Volume of molten pool (m^3)	1.28	1.82	2.41	2.94	2.94	3.81	1.16	1.16
Total mass of UO2 in pool (kg)	9,220	1.29×10^4	1.70×10^4	2.09×10^4	2.09×10^4	2.67×10^4	8,770	8,770
Total mass of metallic Zr (kg)	0	131.0	378.0	378.0	378.0	989.0	334.0	335.0
Mass of liquefied material in partial liquefied porous debris (kg)	6,080	5,780	6,460	7,310	1.06×10^4	1.0×10^4	8,750	1.19×10^4
Total hydrogen production rate (kg/s)	0.083	0.0256	0.015	0.00736	0.0191	0.00279	0.00484	0.0650