Uncertainty and Sensitivity Analysis of Void Reactivity Feedback for 3D BWR Assembly Model

Table 2

Uncertainties of input data.

Index of parameter	Variable	Units	Distribution	Min.	Max.	Nominal
1	Selection of cross section library		Discrete	44 ENDF/B-V		238 ENDF/B-VII
				238 ENDF/B-V
				238 ENDF/B-VI
				238 ENDF/B-VII
2	Fuel pellet half pitch	cm	Normal	0.4335	0.4355	0.4345
3	Cladding half pitch	cm	Normal	0.5000	0.5050	0.5025
4	Fuel pellet density		Normal	99%  ×  X	101%  ×  X	X
5	Enrichment (U-235)		Normal	3.90%	4.00%	3.95%
6	Enrichment (fissile Pu)		Normal	59%	60.2%	59.6%
7	Fuel temperature	K	Normal	850	950	900
8	Moderator temperature	K	Normal	557	661	559
9	Moderator density	g/cm^3	Normal	−0.004	+0.004	X