Windowed multipole sensitivity to target accuracy of the optimization procedure

Figures & data

Figure 1. Library generation mechanism for windowed multipole.

Table 1. Library window and curve fit order.

	Max relative	Inner window	Curve fit
Isotope	error	(eV)	order
^235U	0.01 %	1	6
	0.1 %	1	2
	1 %	1	2
	10 %	1	2
^238U	0.01 %	10	3
	0.1 %	10	2
	1 %	10	2
	10 %	10	2

Figure 2. Multipole library resonance integral compared to MCNP6-sourced data, ²³⁵U.

Figure 3. Multipole library resonance integral compared to MCNP6-sourced data, ²³⁸U.

Figure 4. Cross section evaluation time in microseconds, ²³⁵U.

Figure 5. Cross section evaluation time in microseconds, ²³⁸U.

Table 2. Memory requirements for windowed multipole.

Library	^235U Mem. kB	^238U Mem. kB
10%	543	542
1%	543	542
0.1%	543	542
0.01%	841	589

Table 3. Memory requirements for the MCNP6-sourced data.

Temperature	^235U Mem. kB	^238U Mem. kB
0.1 K	12,993	21,014
250 K	4478	9014
293.6 K	4240	8693
600 K	3370	7391
900 K	3005	6769
1200 K	2795	6374
2500 K	2429	5514

Table 4. Assembly OpenMC run settings.

Parameter	Value
Inactive batches	200
Active batches	500
Neutrons per batch	4 million

Table 5. Assembly OpenMC eigenvalue.

Data	Eigenvalue
MCNP6	1.21201 ± 0.00002
10% multipole	1.21216 ± 0.00002
1% multipole	1.21209 ± 0.00002
0.1% multipole	1.21206 ± 0.00002

Figure 6. Fission production rate relative error, 0.1% target library.

Figure 7. Fission production rate relative error, 1% target library.

Figure 8. Fission production rate relative error, 10% target library.