Preliminary Modeling to Support the TREAT Hodoscope System for Fuel Motion Monitoring

Technical Report · Sun May 01 00:00:00 EDT 2016

DOI:https://doi.org/10.2172/1484292· OSTI ID:1484292

Thompson, Scott J. ^[1]; Townsend, Clive H. ^[1]; Chichester, David L. ^[1]; Johnson, James T. ^[1]; Schley, Robert S. ^[1]

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1. Idaho National Laboratory (INL), Idaho Falls, ID (United States)

Fuel motion is monitored in real time at the Transient Reactor Test Facility (TREAT) using a direct-viewing hodoscope that monitors fast neutrons emitted from test fuel undergoing fission during transients. The hodoscope system is now being refurbished, after over twenty years, to once again support research and development activities examining the survival and failure modes of advanced nuclear reactor fuel systems under accident conditions. An im-portant part of this activity is the development of high-fidelity modeling tools to predict the hodoscope's response to different fuel systems, in different test vehicles, throughout different transient cycles. Initial work has involved the collection of archival data related to how the hodoscope currently at TREAT was manufactured and installed, and the use of this data to create a preliminary radiation transport model using MCNP6. This model is now undergoing refinement to improve its fidelity and to permit its integration with other tools under development to model TREAT transients. The model will be used to study how fast-neutrons measured in the hodoscope's detectors relate to the fission of nuclear material in a test vehicle as a function of location within the vehicle and reactor power. The goal is to develop a time-dependent coupling factor that will relate the measured data to the fuel mass present within each pixel of the hodoscope's field of view. This paper will present the current status of the TREAT hodoscope refurbishment program and modeling activities related to interpreting hodoscope data and inferring fuel motion during transients.

• Research Organization: Idaho National Laboratory (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE)
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 1484292
• Report Number(s): INL/CON--15-36381-Rev000
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
fast neutron
hodoscope
transient modeling
TREAT