Treatment of non-resonant spatial self-shielding effect of double heterogeneous region
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A new approximation method was proposed for treating the non-resonant spatial self-shielding effects of double heterogeneous region such as the double heterogeneous effect of VHTR fuel compact in the thermal energy range and that of BP compact with BISO. The method was developed based on the effective homogenization method and a spherical unit cell model with explicit coated layers and a matrix layer. The self-shielding factor was derived from the relation between the collision probabilities for a double heterogeneous compact and the effective cross section for the homogenized compact. First, the collision probabilities and transmission probabilities for all layers of the spherical model were calculated using conventional collision probability solver. Then, the effective cross section for the homogenized sphere cell representing the homogenized compact was obtained from the transmission probability calculated using the probability density function of a chord length. The verification calculations revealed that the proposed method can predict the self-shielding factor with a maximum error of 2.3% and the double heterogeneous effect with a maximum error of 200 pcm in the typical VHTR problems with various packing fractions and BP compact sizes.
Abstract
A new approximation method was proposed for treating the non-resonant spatial self-shielding effects of double heterogeneous region such as the double heterogeneous effect of VHTR fuel compact in the thermal energy range and that of BP compact with BISO. The method was developed based on the effective homogenization method and a spherical unit cell model with explicit coated layers and a matrix layer. The self-shielding factor was derived from the relation between the collision probabilities for a double heterogeneous compact and the effective cross section for the homogenized compact. First, the collision probabilities and transmission probabilities for all layers of the spherical model were calculated using conventional collision probability solver. Then, the effective cross section for the homogenized sphere cell representing the homogenized compact was obtained from the transmission probability calculated using the probability density function of a chord length. The verification calculations revealed that the proposed method can predict the self-shielding factor with a maximum error of 2.3% and the double heterogeneous effect with a maximum error of 200 pcm in the typical VHTR problems with various packing fractions and BP compact sizes.
참고문헌 (15)
- 조진영, "Improvement and Verification of the DeCART code for HTGR Core Physics Analysis", Nuclear Engineering and Technology, 51(1), pp.13~30 (2019), 한국원자력학회[DOI]
- R. Sanchez, "A statistical analysis of the double heterogeneity problem", Ann. Nucl. Energy, 18, pp.371~395 (1991)
- R. Sanchez, "Treatment of the Double Heterogeneity with the Method of Characteristics", Proc. PHYSOR 2002 (2002)
- S. Y. Choi, "Resonance treatment using pin-based pointwise energy slowing-down method", J. Comput. Phys, 330, pp.134~155 (2017)
- T. Y. Han, "Extension of pin-based point-wise energy slowing-down method for VHTR Fuel with double heterogeneity", Energies, 14, pp.2179~ (2021)
- V.M. Shmakov, "Effective Cross Sections for Calculations of Criticality of Dispersed Media", Proc. PHYSOR 2000 (2000)
- T. Yamamoto, "Extension of effective cross section calculation method for neutron transport calculations in particle-dispersed media", J. Nucl. Sci. Technol, 43, pp.77~87 (2006)
- D. She, "An equivalent homogenization method for treating the stochastic media", Nucl. Sci. Eng, 185, pp.351~360 (2017)
- M. L. Williams, "Resonance self-shielding methodologies in SCALE 6", Nucl. Technol, 174, pp.149~168 (2011)
- DRAGON theory manual, Part 1: collision probability calculations, "G. Marleau", Department de genie mecanique, Ecole Polytechnique de Montreal, ~, pp.Tech. Rep. IGE-236 Revision 1 (2001)
- K.M. Case, "Introduction to the theory of neutron diffusion", pp.21~ (1953)
- A. Gil, "Numerical Methods for Special Functions, Society for Industrial and Applied Mathematics" (2007), Society for Industrial and Applied Mathematics. SIAM
- Prismatic Coupled Neutronics, "Thermal Fluids Transient Benchmark of the MHTGR-350 MW Core Design: Benchmark Definition", J. Ortensi, 2013, NEA[DOI]
- 심형진, "MCCARD: MONTE CARLO CODE FOR ADVANCED REACTOR DESIGN AND ANALYSIS", Nuclear Engineering and Technology, 44(2), pp.161~176 (2012), 한국원자력학회
- Y. H. Kim, "Elimination of double-heterogeneity through a reactivity-equivalent physical transformation", Proc. GLOBAL (2005)