The importance of delayed neutron precursors in gamma dose calculations for activated primary heat exchanger components in the Molten Salt Breeder Reactor

Davidson, Eva E.; Betzler, Benjamin R.; Cao, Yan; Fei, Tingzhou

doi:10.1016/j.anucene.2023.110276

The importance of delayed neutron precursors in gamma dose calculations for activated primary heat exchanger components in the Molten Salt Breeder Reactor

Journal Article · Wed Jan 24 00:00:00 EST 2024 · Annals of Nuclear Energy

DOI:https://doi.org/10.1016/j.anucene.2023.110276· OSTI ID:2371111

^[1]; Betzler, Benjamin R. ^[2]; Cao, Yan ^[3]; Fei, Tingzhou ^[3]

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Radiant Nuclear, El Segundo, CA (United States)
Argonne National Laboratory (ANL), Argonne, IL (United States)

The Molten Salt Reactor (MSR) Multiphysics Applications technical area in the Nuclear Energy Advanced Modeling and Simulation program has supported the development of 3D Monte Carlo models of the Molten Salt Breeder Reactor (MSBR) over the last couple of years. This MSBR model was previously run with the Shift Monte Carlo code to perform radiation shielding calculations in the reactor cell area. The MSBR is a 2250 MWth (1000 MWe) liquid-fueled molten salt reactor design developed at Oak Ridge National Laboratory in the 1970s. Determining the source terms from activated primary heat exchanger (HX) components is important because delayed and prompt neutron fluxes incident on these components affect the dose rate in the primary HX maintenance areas. This information can be used in the development of remote handling procedures required during shutdown for maintenance. A methodology has been developed and is proposed in this paper to quantify the activated source term from the primary HX components as a result of the movement of the delayed neutron precursors in flowing primary fuel salt through the primary HXs in the MSBR. The goal of this research is to evaluate the gamma dose rates in the maintenance hatches above the primary HX using the activated HX source terms. The study showed that the gamma dose rates are approximately two orders of magnitudes higher when accounting for the neutron activation from the movement of delayed neutron precursors through the HXs than when flowing fuel is not considered. Thus, the movement of delayed neutron precursors must be taken into account for accurately predicting the neutron activation of primary loop components.

View Accepted Manuscript (DOE)

Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Idaho National Laboratory (INL), Idaho Falls, ID (United States)

Sponsoring Organization:: USDOE Office of Nuclear Energy (NE), Nuclear Energy Advanced Modeling and Simulation (NEAMS); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)

Grant/Contract Number:: AC05-00OR22725; AC07-05ID14517

OSTI ID:: 2371111

Journal Information:: Annals of Nuclear Energy, Vol. 199; ISSN 0306-4549

Publisher:: ElsevierCopyright Statement

Country of Publication:: United States

Language:: English

References (14)

Implementation, capabilities, and benchmarking of Shift, a massively parallel Monte Carlo radiation transport code Pandya, Tara M.; Johnson, Seth R.; Evans, Thomas M. Journal of Computational Physics, Vol. 308 https://doi.org/10.1016/j.jcp.2015.12.037	journal	March 2016
Transient Convective Delayed Neutron Precursors of 235U for the Molten Salt Reactor Experiment Lee, Kyoung; Jessee, Matthew; Collins, Benjamin International Conference on Physics of Reactors 2022 (PHYSOR 2022) https://doi.org/10.13182/PHYSOR22-37296	conference	January 2022
Isotopic Depletion and Decay Methods and Analysis Capabilities in SCALE Gauld, Ian C.; Radulescu, Georgeta; Ilas, Germina Nuclear Technology, Vol. 174, Issue 2 https://doi.org/10.13182/NT11-3	journal	May 2011
Molten salt reactor neutronics and fuel cycle modeling and simulation with SCALE Betzler, Benjamin R.; Powers, Jeffrey J.; Worrall, Andrew Annals of Nuclear Energy, Vol. 101 https://doi.org/10.1016/j.anucene.2016.11.040	journal	March 2017
Calculating the effective delayed neutron fraction in the Molten Salt Fast Reactor: Analytical, deterministic and Monte Carlo approaches Aufiero, Manuele; Brovchenko, Mariya; Cammi, Antonio Annals of Nuclear Energy, Vol. 65 https://doi.org/10.1016/j.anucene.2013.10.015	journal	March 2014
Primary Shielding Design for an Optimized Molten Salt Reactor Zhang, Zhihong; Xia, Xiaobin; Wang, Jianhua 2013 21st International Conference on Nuclear Engineering, Volume 1: Plant Operations, Maintenance, Engineering, Modifications, Life Cycle and Balance of Plant; Nuclear Fuel and Materials; Radiation Protection and Nuclear Technology Applications https://doi.org/10.1115/ICONE21-15821	conference	February 2014
Modeling and simulation functional needs for molten salt reactor licensing Betzler, Benjamin R.; Heidet, Florent; Feng, Bo Nuclear Engineering and Design, Vol. 355 https://doi.org/10.1016/j.nucengdes.2019.110308	journal	December 2019
Application of Monte Carlo Code Shift for MSBR Dose Rate Calculations Cao, Yan; Davidson, Eva; Betzler, Benjamin International Conference on Physics of Reactors 2022 (PHYSOR 2022) https://doi.org/10.13182/PHYSOR22-37646	conference	January 2022
Automated Variance Reduction of Monte Carlo Shielding Calculations Using the Discrete Ordinates Adjoint Function Wagner, John C.; Haghighat, Alireza Nuclear Science and Engineering, Vol. 128, Issue 2 https://doi.org/10.13182/NSE98-2	journal	February 1998
ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data Chadwick, M. B.; Herman, M.; Obložinský, P. Nuclear Data Sheets, Vol. 112, Issue 12 https://doi.org/10.1016/j.nds.2011.11.002	journal	December 2011
Neutron shielding studies on an advanced molten salt fast reactor design Merk, Bruno; Konheiser, Jörg Annals of Nuclear Energy, Vol. 64 https://doi.org/10.1016/j.anucene.2013.07.014	journal	February 2014
Reactor cell neutron dose for the molten salt breeder reactor conceptual design Davidson, Eva E.; Radulescu, Georgeta; Smith, Kurt Nuclear Engineering and Design, Vol. 383 https://doi.org/10.1016/j.nucengdes.2021.111381	journal	November 2021
FW-CADIS Method for Global and Regional Variance Reduction of Monte Carlo Radiation Transport Calculations Wagner, John C.; Peplow, Douglas E.; Mosher, Scott W. Nuclear Science and Engineering, Vol. 176, Issue 1 https://doi.org/10.13182/NSE12-33	journal	January 2014
Reactor Physics Methods and Analysis Capabilities in SCALE DeHart, Mark D.; Bowman, Stephen M. Nuclear Technology, Vol. 174, Issue 2 https://doi.org/10.13182/NT174-196	journal	May 2011

Similar Records

Application of Shift Ex-Core Calculations to a Detailed MSR Model

Technical Report · Fri Sep 03 00:00:00 EDT 2021 · OSTI ID:1826364

Cao, Yan; Feng, Bo; Davidson, Eva E.; +1 more

Molten Salt Reactor Experiment Simulation using Shift/Griffin

Technical Report · Tue Aug 01 00:00:00 EDT 2023 · OSTI ID:1997706

Hartanto, Donny; Davidson, Eva; Godfrey, Ashley; +3 more

Application of Monte Carlo code SHIFT for MSBR dose rate calculations

Conference · Fri Jul 01 00:00:00 EDT 2022 · OSTI ID:23178745

Cao, Yan; Feng, Bo; Davidson, Eva E.; +1 more

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
Molten Salt Breeder Reactor
facility dose
shift
delayed neutron precursors
hybrid Monte Carlo/deterministic methods

The importance of delayed neutron precursors in gamma dose calculations for activated primary heat exchanger components in the Molten Salt Breeder Reactor

Citation Formats

References (14)

Similar Records

Related Subjects