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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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Framatome begins expansion of facilities in Virginia
An official groundbreaking last week at Framatome’s Mill Ridge Road facility, in Lynchburg, Va., marks the start of a $50 million expansion and an eventual addition of 500 employees, according to the nuclear company.
John Darrell Bess
Nuclear Technology | Volume 166 | Number 3 | June 2009 | Pages 215-229
Technical Paper | 2007 Space Nuclear Conference / Fission Reactors | doi.org/10.13182/NT09-A8836
Articles are hosted by Taylor and Francis Online.
It is proposed that a fast-fission, heatpipe-cooled, lunar-surface power reactor system be divided into subcritical units that could be launched safely without the incorporation of additional spectral shift absorbers or other complex means of control. The reactor subunits are to be emplaced directly into the lunar regolith, utilizing the regolith not just for shielding but also as the reflector material to increase the neutron economy of the system. While a single subunit cannot achieve criticality by itself, coordinated placement of additional subunits will provide a critical reactor system for lunar surface power generation. A lunar regolith clustered-reactor system promotes reliability, safety, and ease of manufacture and testing at the cost of a slight increase in launch mass per rated power level and an overall reduction in neutron economy when compared to a single-reactor system. Additional subunits may be launched with future missions to increase the cluster size and power according to desired lunar-base power demand and lifetime. The results address the potential uncertainties associated with the lunar regolith material and emplacement of the subunit systems. Physical distance between subunits within the clustered emplacement exhibits the most significant feedback regarding changes in overall system reactivity. Narrow, deep holes will be the most effective in reducing axial neutron leakage from the core. The variation in iron concentration in the lunar regolith can directly influence the overall system reactivity, although its effects are less than the more dominant factors of subunit emplacement.