SILENE Benchmark Critical Experiments for Criticality Accident Alarm Systems

Conference · Thu Nov 03 00:00:00 EDT 2011 · Transactions of the American Nuclear Society

OSTI ID:1028751

Miller, Thomas Martin ^[1]; Reynolds, Kevin H. ^[2]

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1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
2. Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States)

In October 2010 a series of benchmark experiments was conducted at the Commissariat a Energie Atomique et aux Energies Alternatives (CEA) Valduc SILENE [1] facility. These experiments were a joint effort between the US Department of Energy (DOE) and the French CEA. The purpose of these experiments was to create three benchmarks for the verification and validation of radiation transport codes and evaluated nuclear data used in the analysis of criticality accident alarm systems (CAASs). This presentation will discuss the geometric configuration of these experiments and the quantities that were measured and will present some preliminary comparisons between the measured data and calculations. This series consisted of three single-pulsed experiments with the SILENE reactor. During the first experiment the reactor was bare (unshielded), but during the second and third experiments it was shielded by lead and polyethylene, respectively. During each experiment several neutron activation foils and thermoluminescent dosimeters (TLDs) were placed around the reactor, and some of these detectors were themselves shielded from the reactor by high-density magnetite and barite concrete, standard concrete, and/or BoroBond. All the concrete was provided by CEA Saclay, and the BoroBond was provided by Y-12 National Security Complex. Figure 1 is a picture of the SILENE reactor cell configured for pulse 1. Also included in these experiments were measurements of the neutron and photon spectra with two BICRON BC-501A liquid scintillators. These two detectors were provided and operated by CEA Valduc. They were set up just outside the SILENE reactor cell with additional lead shielding to prevent the detectors from being saturated. The final detectors involved in the experiments were two different types of CAAS detectors. The Babcock International Group provided three CIDAS CAAS detectors, which measured photon dose and dose rate with a Geiger-Mueller tube. CIDAS detectors are currently in use at Y-12 in the newly constructed Highly Enriched Uranium Materials Facility. The second CAAS detector used a ⁶LiF TLD to absorb neutrons and a silicon detector to count the charge particles released by these absorption events. Lawrence Livermore National Laboratory provided four of these detectors, which had formerly been used at the Rocky Flats facility in the United States.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Oak Ridge Y-12 Plant (Y-12), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1028751
• Journal Information: Transactions of the American Nuclear Society, Vol. ISSN 0003-018X; Coden: TANSAO; Conference: ANS Winter Meeting, Washington, DC (United States), 3-30 Nov 2011
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
22 GENERAL STUDIES OF NUCLEAR REACTORS
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ABSORPTION
ALARM SYSTEMS
BARITE
CEA SACLAY
CONCRETES
CRITICALITY
DOSE RATES
DOSEMETERS
HIGHLY ENRICHED URANIUM
LIQUID SCINTILLATORS
MAGNETITE
NEUTRONS
PHOTONS
RADIATION ACCIDENTS
RADIATION TRANSPORT
SHIELDING
SILENE REACTOR
SILICON
SPECTRA
Nuclear Criticality Safety Program (NCSP)
Commissariat a Energie Atomique et aux Energies Alternatives (CEA)
SILENE Reactor
Thermoluminescent Dosimeters (TLDs)
CIDAS CAAS Detectors