Criticality of Low Enrichment Uranium in Hydrogen

Journal Article · Sun Apr 01 04:00:00 EST 1962 · Nuclear Science and Engineering

OSTI ID:4841045

Mills, C. B. ^[1]; Bell, G. I. ^[1]

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1. Los Alamos Scientific Laboratory (LASL), Los Alamos, NM (United States)

Critical masses of homogeneous water-moderated assemblies containing low enrichment uranium are given. The calculations were made using the multigroup DSN code with eighteen energy groups. Effective absorption cross sections for U²³⁸ were computed with the infinite mass and narrow resonance approximations. The calculations were compared with various experiments and rather good agreement was found. The results are presented as a parametric survey for U²³⁵/U atom ratios from 0.014 to 0.300 and for all H/U²³⁵ ratios for which criticality is possible. The decrease in critical radius with an infinite water reflector is also shown. A bare homogeneous system with U²³⁵/U < 0.010 cannot be made critical at any H/U²³⁵ ratio.

• Research Organization: Los Alamos Scientific Laboratory (LASL), Los Alamos, NM (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-36
• NSA Number: NSA-16-018316
• OSTI ID: 4841045
• Journal Information: Nuclear Science and Engineering, Journal Name: Nuclear Science and Engineering Vol. 12; ISSN 0029-5639
• Publisher: Taylor & Francis
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ABSORPTION
COMPUTERS
CRITICALITY
CROSS SECTIONS
DSN-CODE
ENRICHMENT
GROUP THEORY
HOMOGENEOUS REACTORS
HYDROGEN
MASS
Nuclear Criticality Safety Program (NCSP)
REFLECTORS
RESONANCE
URANIUM 235
URANIUM 238
WATER
WATER MODERATOR