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Results of partially-reflected critical experiments in square-pitched arrays of water-moderated 6.9 percent enriched fuel rods

Transactions of the American Nuclear Society

Harms, Gary A.; Ford, John T.; Campbell, Rafe C.

The Seven Percent Critical Experiment (7uPCX) was designed to provide benchmark criticality and reactor physics data for water-moderated pin-fueled nuclear reactor cores. The enrichment of the fuel was chosen to explore the enrichment range above the current 5% ceiling for US commercial pressurized water reactors. The experiment was part of the US Department of Energy (DOE) Nuclear Energy Research Initiative (NERI) Project 01-124 titled “Reactor Physics and Criticality Benchmark Evaluations for Advanced Nuclear Fuel”. The NERI project was a collaboration between AREVA Federal Services, LLC; the University of Florida; Oak Ridge National Laboratory; and Sandia National Laboratories (SNL). The experiments at Sandia are currently supported by the DOE National Nuclear Security Administration Nuclear Criticality Safety Program. Two sets of benchmark experiments have been completed and documented as LEU-COMP-THERM-080 and LEU-COMP-THERM-078. Those experiments were done with the number of fuel rods in the fully-reflected array as the approach parameter. The experiments reported here are similar to those in LEU-COMP-THERM-080 except that the arrays are partially-reflected – the arrays were larger than would be possible with full reflection and the approach-to-critical experiments were done with the depth of the water in the critical assembly as the approach parameter. These experiments are reported as LEU-COMP-THERM-096.

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Experiments with partially-reflected square-pitched arrays of water-moderated 6.9 percent enriched UO2 fuel rods

ICNC 2015 - International Conference on Nuclear Criticality Safety

Harms, Gary A.; Miller, Allison D.; Ford, John T.; Campbell, Rafe C.

The Seven Percent Critical Experiment (7uPCX) at Sandia National Laboratories was designed to provide benchmark criticality and reactor physics data for water-moderated pin-fueled nuclear reactor cores in the 5 to 10 percent enrichment range. Approach-to-critical experiments were performed on nineteen partially-reflected arrays of pure water-moderated and -reflected fuel rods with a fuel-to-water volume ratio of 0.67. Those configurations are described and the results of the measurements are reported in this paper.

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Current status of the doe nuclear criticality safety program hands-on criticality safety training course at sandia

Topical Meeting Held by the ANS Nuclear Criticality Safety Division, NCSD 2013 - Criticality Safety in the Modern Era: Raising the Bar

Harms, Gary A.; Knief, Ronald A.; Miller, Allison D.; Ford, John T.

A hands-on critical-experiment training class has been developed by the US DOE Nuclear Criticality Safety Program using the water-moderated pin-fueled critical experiments at Sandia National Laboratories. The class is offered as part of the NCSP training program for Nuclear Criticality Safety Engineers in a facility that allows attendance by both cleared and uncleared personnel. Laboratory exercises have been developed that demonstrate the effects of varying a number of the parameters that are considered important to criticality safety. Accompanying the experiments is a series of classroom presentations that emphasize the concepts that are demonstrated in the experiments.

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Results of critical experiments on water-moderated fully-reflected 6.90% enriched UO2 fuel pin arrays with a fuel-to-water volume ratio of 0.52

Topical Meeting Held by the ANS Nuclear Criticality Safety Division, NCSD 2013 - Criticality Safety in the Modern Era: Raising the Bar

Harms, Gary A.; Miller, Allison D.; Ford, John T.

The Seven Percent Critical Experiment (7uPCX) at Sandia National Laboratories was designed to provide benchmark criticality and reactor physics data for water-moderated pin-fueled nuclear reactor cores in the 5 to 10 percent enrichment range. Approach-to-critical experiments were performed on fifteen roughly cylindrical pure water-moderated and -reflected 7uPCX configurations with a fuel-to-water volume ratio of 0.52. Those configurations are described and the results of the measurements are reported in this paper.

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Benchmark experiments in water-moderated fully-reflected 6.90% enriched UO2 fuel rod lattices with a fuel-to-water volume ratio of 0.52

Transactions of the American Nuclear Society

Harms, Gary A.; Miller, Allison D.; Ford, John T.

A second set of experiments in the Seven Percent Critical Experiment (7uPCX) has been completed. Additionally, an evaluation of the experiments as criticality safety benchmark experiments has been performed. The Reviews of the benchmark evaluation have been completed. This evaluation will be published in the 2013 edition of the International Handbook of Evaluated Criticality Benchmark Experiments as LEU-COMP-THERM-078 (LCT078). This presentation is a brief tour of these experiments.

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Results from the First Set of Criticals In the Seven Percent Critical Experiment [Slides]

Harms, Gary A.; Ford, John T.

This presentation discusses the recent Sandia critical experiments, specifically the Seven Percent Critical Experiment (7uPCX) which is a Nuclear Energy Research Initiative (NERI) project. It also discusses why 7uPCX was used, how 7uPCX is operated and presents some 7uPCX results. The presentation concludes by discussing future plans for the critical experiments.

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Critical experiments at Sandia National Laboratories : technical meeting on low-power critical facilities and small reactors

Ford, John T.; Miller, Allison D.

Sandia National Laboratories (SNL) has conducted radiation effects testing for the Department of Energy (DOE) and other contractors supporting the DOE since the 1960's. Over this period, the research reactor facilities at Sandia have had a primary mission to provide appropriate nuclear radiation environments for radiation testing and qualification of electronic components and other devices. The current generation of reactors includes the Annular Core Research Reactor (ACRR), a water-moderated pool-type reactor, fueled by elements constructed from UO2-BeO ceramic fuel pellets, and the Sandia Pulse Reactor III (SPR-III), a bare metal fast burst reactor utilizing a uranium-molybdenum alloy fuel. The SPR-III is currently defueled. The SPR Facility (SPRF) has hosted a series of critical experiments. A purpose-built critical experiment was first operated at the SPRF in the late 1980's. This experiment, called the Space Nuclear Thermal Propulsion Critical Experiment (CX), was designed to explore the reactor physics of a nuclear thermal rocket motor. This experiment was fueled with highly-enriched uranium carbide fuel in annular water-moderated fuel elements. The experiment program was completed and the fuel for the experiment was moved off-site. A second critical experiment, the Burnup Credit Critical Experiment (BUCCX) was operated at Sandia in 2002. The critical assembly for this experiment was based on the assembly used in the CX modified to accommodate low-enriched pin-type fuel in water moderator. This experiment was designed as a platform in which the reactivity effects of specific fission product poisons could be measured. Experiments were carried out on rhodium, an important fission product poison. The fuel and assembly hardware for the BUCCX remains at Sandia and is available for future experimentation. The critical experiment currently in operation at the SPRF is the Seven Percent Critical Experiment (7uPCX). This experiment is designed to provide benchmark reactor physics data to support validation of the reactor physics codes used to design commercial reactor fuel elements in an enrichment range above the current 5% enrichment cap. A first set of critical experiments in the 7uPCX has been completed. More experiments are planned in the 7uPCX series. The critical experiments at Sandia National Laboratories are currently funded by the US Department of Energy Nuclear Criticality Safety Program (NCSP). The NCSP has committed to maintain the critical experiment capability at Sandia and to support the development of a critical experiments training course at the facility. The training course is intended to provide hands-on experiment experience for the training of new and re-training of practicing Nuclear Criticality Safety Engineers. The current plans are for the development of the course to continue through the first part of fiscal year 2011 with the development culminating is the delivery of a prototype of the course in the latter part of the fiscal year. The course will be available in fiscal year 2012.

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Results 1–25 of 31
Results 1–25 of 31