Utilization of PARCS/Serpent in small-scale reactor – Multiplication factor, rod worth, and transient

• Published in: Annals of nuclear energy Vol. 166; p. 108757
• Main Authors: Fejt, F., Suk, P., Frybort, J., Rataj, J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2022
• Subjects: Homogenization; PARCS; Serpent; Transient; Transport correction; VR-1; VR-1; Transport correction; Homogenization; Serpent; Transient; PARCS
• ISSN: 0306-4549; 1873-2100
• DOI: 10.1016/j.anucene.2021.108757

•Methods and results are verified on 7 different core configurations.•Cross-section homogenization based on different approaches.•Analyses of a general cross-section library at VR-1 for deterministic codes.•Analyses of general core kinetics parameters at VR-1.•Steady-state and transient experiments to support the calculation results. The paper is focused on utilization of calculation code PARCS (version 3.3.1) for the VR-1 reactor. Macroscopic cross-sections are generated by stochastic code Serpent (version 2.1.30) with ENDF/B-VIII.0 library and with a high emphasis on a wide range of utilization and reproducibility. The VR-1 reactor is characterized by small-sized core configurations (28.6 × 28.6 cm up to 42.9 × 42.9 cm; height of 60 cm; pitch 7.15 cm) that are imposing special requirements on a cross-section homogenization. Published cross-section generation approaches are used for analyses of 7 highly distinctive core configurations. This allows to asses their performance in a wider range than other papers aiming only at one specific core configuration. Even though predictions of a critical state are not sufficiently accurate for any actual usage (in case of the VR-1 reactor), calculated absorption rod worths reach a high potential for a fast and precise evaluation of safety criteria. Core kinetics parameters generated by Serpent with ENDF/B-VIII.0 library (for all three methods: Meulekamp, Nauchi, IFP) show a continuous underestimation of calculated power in all investigated transients during an insertion of a negative reactivity.