An evolution strategy for lunar nuclear surface power

The production and transmission of electric power for a permanently inhabited lunar base poses a significant challenge which can best be met through an evolution strategy. Nuclear systems offer the best opportunity for evolution in terms of both life and performance. Applicable nuclear power technology options include isotope systems (either radioisotope thermoelectric generators or dynamic isotope power systems) and reactor systems with either static (thermoelectric or thermionic) or dynamic (Brayton, Stirling, Rankine) conversion. A power system integration approach that takes evolution into account would benefit by reduced development and operations cost, progressive flight experience, and simplified logistics, and would permit unrestrained base expansion. For the purposes of defining a nuclear power system evolution strategy, the lunar base development shall consist of four phases: precursor, emplacement, consolidation, and operations

Physics Potential of SPS Upgrade in regard to Beta/EC Beams

The goal for future neutrino facilities is the determination of the $[U_{e3}]$ mixing and CP violation in neutrino oscillations. This will require precision experiments with a very intense neutrino source. With this objective the creation of neutrino beams from the radioactive decay of boosted ions by the SPS of CERN from either beta or electron capture transitions has been propossed. We discuss the capabilities of such facilities as a function of the energy of the boost and the baseline for the detector. We conclude that the SPS upgrade to 1000 GeV is crucial to have a better sensitivity to CP violation if it is accompanied by a longer baseline. We compare the physics potential for two different configurations. In the case of beta beams, with the same boost for both $\beta^+$ (neutrinos) and $\beta^-$ (antineutrinos), the two setups are: I) $\gamma=120$, L=130 Km (Frejus); II) $\gamma=330$, L=650 Km (Canfranc). In the case of monochromatic EC beams we exploit the energy dependence of neutrino oscillations to separate out the two parameters $U(e3)$ and the CP phase $\delta$. Setup I runs at $\gamma=90$ and $\gamma=195$ (maximum achievable at present SPS) to Frejus, whereas Setup II runs at $\gamma=195$ and $\gamma=440$ (maximum achievable at upgraded SPS) to Canfranc. The main conclusion is that, whereas the gain in the determination of $U(e3)$ is rather modest, setup II provides much better sensitivity to CP violation.Comment: 6 pages, 10 figures, Proceedings of LHC LUMI 2006 CARE-HHH-AP Wokshop, October 2006, Valenci

Micropiles for Support of Heavy Crane Ring Foundation

The replacement of a steam generator at a nuclear power plant was accomplished with the use of a massive crane, believed to be one of the largest available cranes in the world market. Four steam generators were replaced, with each generator weighing 3.2 MN. The crane used for the job had a circular support that required a ring foundation. The crane support imposed huge loads on the ring foundation. Because of the presence of soft to medium stiff clayey fill on one side of the ring foundation, the load-sensitive nature of existing underground safetyrelated duct banks, and the nature of the loads applied to the foundation, it was necessary to support the ring foundation on piles. In order to minimize vibrations next to the containment building (the plant was operational while the piles were being installed), micropiles were selected. A total of 80 micropiles were installed, most of them at a batter of 10o from vertical, to provide the required vertical and lateral load resistance. Despite significant challenges imposed by space constraints, subsurface conditions, buried utilities, and design changes, the micropiles were installed within schedule, and performed as designed

Preliminary survey of 21st century civil mission applications of space nuclear power

The purpose was to collect and categorize a forecast of civilian space missions and their power requirements, and to assess the suitability of an SP-100 class space reactor power system to those missions. A wide variety of missions were selected for examination. The applicability of an SP-100 type of nuclear power system was assessed for each of the selected missions; a strawman nuclear power system configuration was drawn up for each mission. The main conclusions are as follows: (1) Space nuclear power in the 50 kW sub e plus range can enhance or enable a wide variety of ambitious civil space mission; (2) Safety issues require additional analyses for some applications; (3) Safe space nuclear reactor disposal is an issue for some applications; (4) The current baseline SP-100 conical radiator configuration is not applicable in all cases; (5) Several applications will require shielding greater than that provided by the baseline shadow-shield; and (6) Long duration, continuous operation, high reliability missions may exceed the currently designed SP-100 lifetime capabilities

Bezpečnosti JE na Slovensku z pohľadu záťažových testov po nehode vo Fukushimi

This paper presents the new requirements to test of the safety and reliability of the NPP structures due to the last nuclear accidents in the world. The accidents of the NPP in Chernobyl and Fukushima give us the new inspiration to verify the safety level of the NPP structures. The probabilistic assessment of NPP structures for PSA level 2 of VVER 440 in the case of LOCA accident is presented. The results of the probabilistic nonlinear analysis of the NPP structures are presented.Článok sa zaoberá novými požiadavkami na testovanie bezpečnosti a spoľahlivosti konštrukcií JE v dôsledku posledných jadrových nehôd vo svete. Havárie JE v Černobile a vo Fukushimi dávajú nové inšpirácie pre verifikovanie úrovne bezpečnosti konštrukcií JE. Rozoberá sa pravdepodobnostná metodológia konštrukcií JE pre PSA úrovne 2 reaktora VVER 440 v prípade havárie LOCA. Uvádzajú sa výsledky pravdepodobnostnej nelineárnej analýzy konštrukcií JE