Speaker
Description
Depletion codes such as VESTA 2.2 [1] are used to calculate the time evolution of a material subjected to radiation for a wide variety of applications in the fields of nuclear safety, radiation protection and environmental health safety. For these applications, experimental validation is paramount. VESTA 2.2, which allows coupling both MCNP6 [2] and/or MORET 5 [3] Monte Carlo codes to a depletion module, has been recently released. Over the last couple of years, IRSN has established an important experimental validation database of VESTA 2.2 using a set of 104 samples of radiochemical assay data and decay heat measurements for a wide variety of reactor and fuel types (PWR, BWR, VVER, MOX, UO2, UO2-Gd2O3 fuel) [4, 5, 6]. This experimental validation work has been performed for four different nuclear data libraries, namely JEFF-3.1, JEFF-3.2, ENDF/B-VII.0 and ENDF/B-VII.1.
Nuclear data libraries, namely JEFF-3.3 [7] and ENDF/B-VIII.0 [8], have recently been released. Decay heat validation calculations were performed with VESTA 2.2 using these libraries. The experiments that have been selected for this work are the CLAB [9], GE Morris [10] and HEDL [10] PWR UO2 assembly decay heat measurements.
In this paper, we will first provide an overview of the selected decay heat experiments from the experimental validation database. This will be followed by the presentation of the new VESTA 2.2 validation results for decay heat calculations obtained with JEFF-3.3 and ENDF/B-VIII.0 libraries. Finally, a comparison of these results with the results obtained in the past with the older JEFF and ENDF/B libraries will be performed and commented on.
[1] W. Haeck and B. Dechenaux, “VESTA 2.2 User’s Manual,” PSN-EXP/SNC/2017-251, Institut de Radioprotection et de Sûreté Nucléaire (2018).
[2] J. S. Hendricks et al., “MCNPX, VERSION 2.6.a”, LA-UR-05-8225, Los Alamos National Laboratory, USA (2005).
[3] B. Cochet et al., “Capabilities Overview of the MORET 5 Monte Carlo Code,” Proceedings of Joint Int. Conf. Supercomputing in Nuclear Applications and Monte Carlo 2013 (SNA + MC 2013), Paris, France, October 27–31, (2013).
[4] R. Ichou, “Validation of VESTA 2.2.0 Volume 1: Methodology and overview of results,” Rapport IRSN/2020-00269, Institut de Radioprotection et de Sûreté Nucléaire (2020).
[5] R. Ichou and B. Dechenaux, “On the validation of VESTA 2.2.0 using the ARIANE GU3 sample,” Proceedings of PHYSOR 2020, Cambridge, United Kingdom, March 29th – April 2nd (2020).
[6] D. Rochman et al., “Analysis of the ARIANE GU3 sample: nuclide inventory and decay heat,” Eur. Phys. J. Nuclear Sci. Technol., 7, 14 (2021).
[7] A. J. M. Plompen et al., “The joint evaluated fission and fusion nuclear data library, JEFF-3.3,” Eur. Phys. J. A, pp. 56-181 (2020).
[8] D. A. Brown et al., “ENDF/B-VIII.0: the 8th major release of the nuclear reaction data library with CIELO-project cross sections, new standards and thermal scattering data,” Nuclear Data Sheets, 148 pp. 1-142 (2018).
[9] F. Sturek, L. Agrenius, “Measurements of decay heat in spent nuclear fuel at the Swedish interim storage facility CLAB”, Svensk Karnbranslehantering AB, SKB Rapport R-05-62, December 2006.
[10] I. Gauld, G. Illas, B. D. Murphy, C. F. Weber, “Validation of SCALE 5 Decay Heat Predictions for LWR Spent Nuclear Fuel”, Oak Ridge National Laboratory, NUREG/CR-6972, ORNL/TM-2008/015 (2010).