Decomposition Analysis of Void Reactivity Coefficient for Innovative and Modified BWR Assemblies

Table 1

Innovative BWR fuel assemblies’ specifications.

Fuel assembly design	UO2	MOX	MOX + 8 holes	MOX + 12 holes
Discharge burnup (GWd/t)	70
Geometrical configuration	9×9	10×10
Number of fuel rods	74	91	83	79
Average enrichment (wt%)	5.50	6.97	6.83	6.56
Number of U-Gd rods	16	14
Assembly pitch (cm)	15.24
Fuel rod pitch (cm)	1.440	1.295
Moderator-to-fuel ratio	1.89	1.90	2.18	2.35