Critical Configuration and Physics Mesaurements for Graphite Reflected Assemblies of U(93.15)O2 Fuel Rods (1.27-CM Pitch)

Margaret A. Marshall

关键词: BERYLLIUM;    BOILING;    CADMIUM;    COMMUNICATIONS;    CONFIGURATION;    EVALUATION;    FUEL PELLETS;    FUEL RODS;    GRAPHITE;    MOCKUP;    PHYSICS;    POTASSIUM;    PRODUCTION;    REACTOR PHYSICS;    SPACE POWER REACTORS;    STAINLESS STEELS;    VALIDATION acceptable benchmark;    cadmium ratios;    close packed;    critical experiments;    dioxide;    fission rates;    graphite reflected;    highly enriched;    reactivity worth measurements;    unmoderated;    uranium;   

DOI  :  10.2172/1042389
RP-ID  :  INL/EXT-11-23295
PID  :  OSTI ID: 1042389
Others  :  TRN: US1202864

美国|英语

来源: SciTech Connect

【 摘 要 】

A series of critical experiments were completed in 1962-1965 at Oak Ridge National Laboratory's Critical Experiments Facility in support of the Medium-Power Reactor Experiments (MPRE) program. In the late 1950's efforts were made to study 'power plants for the production of electrical power in space vehicles'. The MPRE program was a part of those efforts and studied the feasibility of a stainless steel system, boiling potassium 1 MW(t), or about 140 kW(e), reactor. The program was carried out in FY 1964, 1965, and 1966. A summary of the program's effort was compiled in 1967. The delayed critical experiments served as a mockup of a small, potassium-cooled space power reactor for validation of reactor calculations and reactor physics methods. Initial experiments, performed in November and December of 1962, consisted of a core of unmoderated 253 stainless steel tubes, each containing 26 UO2 fuel pellets, surrounded by a graphite reflector. Measurements were made to determine critical reflector arrangements, fission-rate distributions, and cadmium ratio distributions. Subsequent experiments used beryllium reflectors and also measured the reactivity for various materials placed in the core. 'The [assemblies were built] on [a] vertical assembly machine so that the movable part was the core and bottom reflector.' The experiment studied within this evaluation was the first of the series and had the 253 fuel tubes packed tightly into a 22.87 cm outside diameter (OD) core tank. Two critical configurations were found by varying the amount of graphite reflector (References 1 and 2). Information for this evaluation was compiled from Reference 1 and 2, reports on subsequent experiments in the series, and the experimental logbook as well as from communication with the experimenter, John T. Mihalczo.