Uncertainty quantification of neutron multiplication factors of light water reactor fuels during depletion

Figures & data

Figure 1. Burnup chain related to xenon-131 generation.

Figure 2. Example of reaction branching ratio uncertainty in a simplified chain induced by decay branching ratio uncertainty in an original chain.

Figure 3. Geometrical specification of 3 x 3 multi-cell including burnable neutron absorber.

Figure 4. Infinite neutron multiplication factors during fuel depletion.

Table 1. Root-mean-square (RMS) and maximum relative errors in variance of number densities after fuel depletion

FP	Number of	FY-induced		DBR-induced
chain	samples	RMS	Max.	RMS	Max.
FP-138	100	0.102	0.316 (Pm-149*)	0.493	2.731 (Xe-131)
	1,000	0.035	0.112 (Sm-150)	0.034	0.088 (Pd-107)
	10,000	0.013	0.025 (Eu-155)	0.017	0.076 (Xe-131)
FP-139	100	0.102	0.315 (Pm-149)	0.132	0.482 (Pd-107)
	1,000	0.035	0.113 (Sm-150)	0.032	0.088 (Pd-107)
	10,000	0.013	0.026 (Eu-155)	0.011	0.028 (Mo-95)

^*Number densities of this nuclide give the maximum error in variance.

Figure 5. Nuclear data-induced uncertainty of infinite neutron multiplication factors during fuel depletion.

Figure 6. Correlation matrices of nuclear data-induced uncertainty of infinite neutron multiplication factors during fuel depletion.

Figure 7. Component-wise nuclear data-induced uncertainty of k_∞ during fuel depletion.

Figure 8. Nuclide-wise reaction cross section-induced uncertainty of k_∞ during fuel depletion.

Figure 9. Energy-integrated sensitivity of k_∞ with respect to uranium-238 capture cross sections.

Figure 10. FP nuclides capture cross section-induced uncertainty of k_∞ during fuel depletion.

Figure 11. Energy-integrated sensitivity of k_∞ in 3 x 3 multi-cell with respect to gadolinium-155 and −157 capture cross sections.

Figure 12. Energy-integrated sensitivity of k_∞ in single cell with respect to capture cross sections of FP nuclides.

Figure 13. Energy spectra of sensitivities of k_∞ in a single cell with respect to capture cross sections of FP nuclides.

Figure 14. Nuclear data-induced uncertainty of k_∞ after specific cooling period.

Figure 15. Nuclide-wise nuclear data-induced uncertainty of k_∞ after specific cooling period.

Figure 16. Energy-integrated sensitivity of k_∞ after 5-year cooling with respect to capture cross sections of plutonium-241 and americium-241.

Figure 17. FP nuclides nuclear data-induced uncertainty of k_∞ after specific cooling period.

Figure 18. Energy-integrated sensitivity of k_∞ in single cell with respect to capture cross sections of FP nuclides.