Evaluation of improved subgroup resonance treatment based on Sanchez-Pomraning method for double heterogeneity in PWR. (August 2020)

• Record Type: Journal Article
• Authors: Li, Song; Zhang, Qian; Zhang, Zhijian; Zhao, Qiang; Liang, Liang; Liang, Yuechao; Zhang, Jinchao; Lou, Lei
• Is Part Of: Annals of nuclear energy. Volume 143(2020)
• Publication Date: 2020-08
• Subjects: Resonance self-shielding -- Subgroup method -- Ultra-fine group method -- Double heterogeneity -- Sanchez-Pomraning method; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2020.107491
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: The Sanchez-Pomraning based subgroup method is used for the double heterogeneity. The DH MOC is used twice for resonance calculation and once again for eigenvalue. The region-wise resonance cross section inside the particles could be obtained. Abstract: The feasibility of the improved subgroup method coupled with the Sanchez-Pomraning Method (ISSP) is analyzed for the resonance self-shielding calculation of double heterogeneity (DH) problems in PWR. The Sanchez-Pomraning method is developed for both fixed source and the eigenvalue problems. The improved subgroup method adopts a fine-mesh energy structure to handle the resonance interference effect. In this process, the subgroup fixed source equations are solved to get the fine-mesh cross section and the slowing-down equations are solved for group condensation. To extend the improved subgroup method to DH condition, the Sanchez-Pomraning method is applied twice to the subgroup fixed source equation and slowing-down equation respectively. Afterward, the Sanchez-Pomraning method is used the third time for multi-group transport problems. The ultra-fine group method coupled with the Sanchez-Pomraning method (UFGSP) is also established for comparison with ISSP. Numerical validation shows that both ISSP and UFGSP could treat the DH resonance effect precisely.