Further Studies with the GCRE Critical Assembly

Technical Report · Mon Dec 29 04:00:00 EST 1958

DOI:https://doi.org/10.2172/4182193· OSTI ID:4182193

Dingee, David A. ^[1]; Ballowe, William C. ^[1]; Egen, Raymond A. ^[1]; Jankowski, Francis J. ^[1]; Chastain, Jr., Joel W. ^[1]

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1. Battelle Memorial Inst., Columbus, OH (United States)

Further engineering and physics data to aid in constructing GCRE-1 were obtained in critical-assembly studies. Four major experiments were performed to investigate the effect on reactivity caused by changes in axial reflector materials, the effect on reactivity and the power perturbation caused by fast safety control-blade guides, the effect of changes in fuel-element material composition, and the effect of changes in fuel-element spacing designed to produce uniform radial power-generation rates. All studies were performed with a 4-in.-thick lead reflector at the core perimeter. Axial-reflector-material studies employed combinations of aluminum and steel reflectors. The reactivity worth of a 2 3/4-in.-thick steel reflector was +0.414% Δk/k compared with 0.175% Δk/k for a similar aluminum reflector. The perturbation in the flux distribution caused by the safety-blade guides was localized, and affected only the regions immediately adjacent to the guides. The combined reactivity worth of two guides was -0.281% Δk/k. Fuel-element material compositions were changed by separate additions of fuel and stainless steel. An increase in uranium loading from an average value of 303 to 404 g per element would provide, based on extrapolations from experimental data, a reactivity of about 4.5% Δk/k. An increase in steel from 1708 to 2093 g per element decreased the core reactivity by about 1.1% Δk/k. A change in fuel-element spacing reduced the ratio of maximum to average power generation from 1.46 to 1.24.

• Research Organization: Battelle Memorial Inst., Columbus, OH (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Nuclear Criticality Safety Program (NCSP); US Atomic Energy Commission (AEC)
• DOE Contract Number: W-7405-ENG-92
• NSA Number: NSA-14-008278
• OSTI ID: 4182193
• Report Number(s): BMI-1306
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALUMINUM
Analysis
CONFIGURATION
CONTROL ELEMENTS
CRITICAL ASSEMBLIES
Critical Assembly
Criticality
FUEL ELEMENTS
Fuel Element
GAS COOLANT
GCRE
GCRE-1
Gas Coolant
Gas Cooled Reactor
LEAD
NEUTRON FLUX
Nuclear Criticality Safety Program (NCSP)
POWER
POWER PLANTS
Power
REACTIVITY
REACTOR CORE
REACTORS
REFLECTORS
STAINLESS STEELS
STEELS
Safety
URANIUM
VARIATIONS