Investigations of Rod Positions for Treat M8CAL Analyses

[+] Author and Article Information
Zachary Weems

Nuclear Engineering Program,
University of Florida,
3230 Innovation Blvd Room 1421, K8-34,
Richland, WA 99354
e-mail: weems1@ufl.edu

Sedat Goluoglu

Nuclear Engineering Program,
University of Florida,
549 Gale Lemerand Dr,
Gainesville, FL 32611-6400
e-mail: goluoglu@mse.ufl.edu

Mark D. DeHart

Idaho National Laboratory,
Reactor Physics Design and Analysis Department,
2525 North Freemont St.,
Idaho Falls, ID 83415
e-mail: mark.dehart@inl.gov

1Corresponding author.

Manuscript received July 24, 2017; final manuscript received December 7, 2017; published online May 16, 2018. Assoc. Editor: Dmitry Paramonov.The United States Government retains, and by accepting the article for publication, the publisher acknowledges that the United States Government retains, a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for United States Government purposes.

ASME J of Nuclear Rad Sci 4(3), 031017 (May 16, 2018) (7 pages) Paper No: NERS-17-1071; doi: 10.1115/1.4038929 History: Received July 24, 2017; Revised December 07, 2017

The transient reactor test facility (TREAT), a graphite moderated experimental reactor, is scheduled to restart in late 2017. There is now renewed interest in development of capabilities to model and simulate the TREAT transients using three-dimensional coupled physics. To validate existing transient analysis tools as well as those under development, several temperature-limited transients have been modeled and analyzed. These transients are from the M8 calibration (M8CAL) experiment series, a set of experiments performed to calibrate the reactor detectors for the planned M8 series of fuel tests. Detailed reactor models were prepared that were then used to calculate the pretransient and post-transient keff values as well as corresponding reactivity insertions. Alterations to modeled values of shutdown and initial transient rod insertion depths were made to better match the reported experimental values of reactivity insertions assuming just critical pretransient states. It was found that two of the altered media inputs, fuel and Zircaloy-3 cladding, had significant effects on the keff. In addition, increasing shutdown rod insertion by 3–5 cm and decreasing initial transient rod insertion by 1–2 cm gave perfect pretransient keff and total reactivity insertion values. However, the revised positions are as much as a factor of 3–20 different from reported uncertainty of 0.762 cm. This suggests that boron concentration uncertainties may play a significant role in accurately modeling the TREAT transients and should be investigated thoroughly.

Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.


Bess, J. , and DeHart, M. D. , 2015, “Baseline Assessment of TREAT for Modeling and Analysis,” Idaho National Laboratory, Idaho Falls, ID, Report No. INL/EXT—15-35372.
Lyons, P. , and Crowell, B. , 2015, “Development of Light Water Reactor Fuels With Enhanced Accident Tolerance,” Report to Congress, United States Department of Energy, Washington, DC. https://energy.gov/sites/prod/files/2015/06/f23/Report%20to%20Congress%20-%20Accident%20Tolerant%20Fuels.pdf
Robinson, W. R. , and Bauer, T. H. , 1994, “The M8 Power Calibration Experiment (M8CAL),” Argonne National Laboratory, Argonne, IL, Report No. ANL-IFR-232. https://www.osti.gov/scitech/servlets/purl/1130413
ORNL, 2011, “SCALE: A Comprehensive Modeling and Simulation Suite for Nuclear Safety Analysis and Design,” Oak Ridge National Laboratory, Oak Ridge, TN, Standard No. ORNL/TM-2005/39.
Goluoglu, S. , Petrie, L. M. , Dunn, M. E. , Hollenbach, D. F. , and Rearden, B. T. , 2011, “ Monte Carlo Criticality Methods and Analysis Capabilities in SCALE,” Nucl. Technol., 174(2), pp. 214–235. [CrossRef]
Dehart, M. D. , Baker, B. A. , and Ortensi, J. , 2017, “ Interpretation of Energy Deposition Data From Historical Operation of the Transient Test Facility (TREAT),” Nucl. Eng. Des., 322, pp. 504–521. [CrossRef]


Grahic Jump Location
Fig. 1

A typical fuel element in the TREAT reactor. Fuel consists of cuboids chamfered into octagonal prisms, with long graphite pieces on either end. Cladding is octagonal as well. Taken from Ref. [1].

Grahic Jump Location
Fig. 4

The TREAT core as modeled in KENO-VI, with one quarter and some outer graphite removed for viewing

Grahic Jump Location
Fig. 3

A two-dimensional depiction of M8CAL half-slotted layout, with atypical elements numbered greater than 1000 and given altered color

Grahic Jump Location
Fig. 2

A depiction of the whole TREAT core and external machinery. Taken from Ref. [1].



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In