Figures & data
Figure 1. Brief summary and development history of the past and present studies.
Table 1. Concept of two-step resonance treatment
Table 2. Summary of the main calculation procedures for the present method
Figure 2. Radially sub-divided fuel rod.
Figure 3. Geometrical treatment of spatially dependent fuel escape probability.
Figure 4. Concept for determination of sub-group structure.
Figure 5. Calculation flow of unified resonance treatment (first step).
Figure 6. Calculation flow of unified resonance treatment (second step).
Figure 7. Calculation flow of two-step reaction-rate preservation scheme.
Table 3. Verification list
Table 4. Specifications of the pin-cell model
Figure 8. Geometry of pin-cell model.
Figure 9. Comparison of ultra-fine-group fluxes between the present method (first-step calculation) and the continuous energy Monte-Carlo calculation (MVP).
Table 5. Calculation time for the ultra-fine-group flux
Figure 10. Sub-group cross-sections and their differences from the direct heterogeneous ultra-fine-group calculation results.
Figure 11. Effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP).
Table 6. Differences of effective cross-section from the continuous energy Monte-Carlo calculation (MVP)
Table 7. Estimation for the number of one-group fixed-source transport calculations
Table 8. Brief estimation for the calculation time on fuel assembly geometry
Table 9. Qualitative comparison of overall performance for resonance self-shielding treatments
Figure 12. Correction factors and their differences from the direct heterogeneous ultra-fine-group calculation results.
Figure 13. Reaction-rates and their differences from the continuous energy Monte-Carlo calculation (MVP).
Figure 14. Distribution of fuel isotope composition within a pellet.
Figure 15. Effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) with non-uniform isotope composition.
Figure 16. Effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) for annular fuel.
Figure 17. Distribution of fuel temperature within a pellet.
Figure 18. Effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) with non-uniform fuel temperature.
Figure 19. Azimuthally dependent effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) for unit pin-cell.
Figure 20. Azimuthally dependent effective cross-section ratios in each ring region for unit pin-cell.
Figure 21. Azimuthally dependent effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) for 3×3 multi-cell with large water region (corner fuel).
Figure 22. Azimuthally dependent effective cross-sections and their differences from the continuous energy Monte-Carlo calculation (MVP) for 3×3 multi-cell with large water region (vertical fuel).
