Reconsideration of Inherent Neutron Sources in Liquid Fuel of Molten Salt Reactors

Calculation of inherent neutron sources from alpha-n and gamma-n reactions in molten fluoride fuel salts using current gamma-n and alpha-n cross-sections and codes where possible. Original inherent neutron source was calculated for Molten Salt Reactor Experiment (MSRE) in 1959 using then-determined alpha-n cross-sections and an estimate for gamma-n cross-section for beryllium-9. Values selected to generate conservative neutron population value for determining required external neutron source and operational neutron population. Inherent neutron source values have not been revisited for molten salt fluid fuel reactors since. Updated alpha-n reaction rates per cubic centimeter calculated using SOURCES4C, compared against original Oak Ridge National Laboratory calculations for MSRE. Fuel salt aging simulated using ORIGEN for 300 days (no power) and a 150-day power cycle at 200 kWt followed by 150 days cooling, alpha-n source calculated by SOURCES4C and compared to alpha-n rates given by ORIGEN. Gamma-n reaction rates calculated from updated normalized cross-sections and compared to original ORNL 0.5 mb cross-section, which was for beryllium-9 salt component only. Recalculated reaction rates are markedly greater than original MSRE rates in fresh (unaged) fuel salt.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Nuclear Engineering

Grantor dc:publisher

The Ohio State University

Year dc:date

2013

Author dc:creator

• Powell, Walter Newton

Contributors dc:contributor

• Cao, Lei

• Nuclear Engineering
• reactor fuels
• fuel salts
• alpha-n
• gamma-n
• neutron sources
• molten salt reactor

Statement dc:rights

• unrestricted
• This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=osu1364909574

OAI identifier oai:identifier

oai:etd.ohiolink.edu:osu1364909574