Feasibility of Fissile Mass Assay of Spent Nuclear Fuel Using ²⁵²Cf-Source-Driven Frequency-Analysis

Conference · Sun Jul 28 00:00:00 EDT 1996

OSTI ID:391688

Mattingly, J. K. ^[1]; Valentine, T. E. ^[2]; Mihalczo, J. T. ^[2]

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1. Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)
2. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Instrumentation and Controls Division, Measurements Science Section

The feasibility was evaluated using MCNP-DSP, an analog Monte Carlo transport code to simulate source-driven measurements. Models of an isolated Westinghouse 17x17 PWR fuel assembly in a 1500-ppM borated water storage pool were used. In the models, the fuel burnup profile was represented using seven axial burnup zones, each with isotopics estimated by the PDQ code. Four different fuel assemblies with average burnups from fresh to 32 GWd/MTU were modeled and analyzed. Analysis of the fuel assemblies was simulated by inducing fission in the fuel using a ²⁵²Cf source adjacent to the assembly and correlating source fissions with the response of a bank of ³He detectors adjacent to the assembly opposite the source. This analysis was performed at 7 different axial positions on each of the 4 assemblies, and the source-detector cross-spectrum signature was calculated for each of these 28 simulated measurements. The magnitude of the cross-spectrum signature follows a smooth upward trend with increasing fissile material (²³⁵U and ²³⁹Pu) content, and the signature is independent of the concentration of spontaneously fissioning isotopes (e.g., ²⁴⁴Cm) and (α,n) sources. Furthermore, the cross-spectrum signature is highly sensitive to changes in fissile material content. This feasibility study indicated that the signature would increase ~100% in response to an increase of only 0.1 g/cm³ of fissile material.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Instrumentation and Controls Division, Measurements Science Section; Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP); USDOE Laboratory Cooperative Postgraduate Research Training Program
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 391688
• Report Number(s): CONF-960767-70; ON: DE96015231; TRN: 96:028382
• Resource Relation: Conference: 37. Annual Meeting of the Institute of Nuclear Materials Management, Naples, FL (United States), 28 Jul - 1 Aug 1996; Other Information: PBD: [1996]
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
97 MATHEMATICS AND COMPUTING
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
FISSILE MATERIALS
RADIOMETRIC ANALYSIS
SPENT FUELS
FUEL ASSEMBLIES
CALIFORNIUM 252
NEUTRON SOURCES
NUCLEAR MATERIALS MANAGEMENT
PWR TYPE REACTORS
HE-3 COUNTERS
FUEL STORAGE POOLS
Nuclear Criticality Safety Program (NCSP)
Monte Carlo Transport Code
Fuel Assemblies
Reactor Fuel Element
Fourier Analyzer
Fuel Burnup Profile
Source-Detector Cross-Spectrum
Pressurized Water Reactor (PWR)