ORALLOY (93.15 235U) METAL ANNULI WITH BERYLLIUM CORE

John D. Bess ; Leland M. Montierth ; Raymond L. Reed ; John T. Mihalczo

关键词: BENCHMARKS;    BERYLLIUM;    CALCULATION METHODS;    CASTING;    CRITICALITY;    CROSS SECTIONS;    EIGENVALUES;    ENRICHED URANIUM;    GRAPHITE;    HIGHLY ENRICHED URANIUM;    NEUTRONS;    OR-CEF REACTOR;    POLYETHYL;   

DOI  :  10.2172/1004261
RP-ID  :  INL/EXT-10-18065
PID  :  OSTI ID: 1004261
Others  :  TRN: US1100957

美国|英语

来源: SciTech Connect

【 摘 要 】

A variety of critical experiments were constructed of enriched uranium metal during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility (ORCEF) in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, two were performed that consisted of uranium metal annuli with a solid beryllium metal core. The outer diameter of the annuli was approximately 13 or 15 inches with an inner diameter of 7 inches. The diameter of the core was approximately 7 inches. The critical height of the configurations was approximately 5 and 4 inches, respectively. The uranium annuli consisted of multiple stacked rings with diametral thicknesses of approximately 2 inches apiece and varying heights. The 15-inch experiment was performed on June 4, 1963, and the 13-inch experiment on July 12, 1963 by J. T. Mihalczo and R. G. Taylor (Ref. 1) with accompanying logbook. Both detailed and simplified model specifications are provided in this evaluation. Both of these fast-spectra experiments were determined to represent acceptable benchmarks. The calculated eigenvalues for both the detailed and simple models are within approximately 0.6% of the benchmark values, but significantly greater than 3s from the benchmark value because the uncertainty in the benchmark is very small: -->