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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
T. Wakabayashi, Y. Hachiya
Nuclear Science and Engineering | Volume 63 | Number 3 | July 1977 | Pages 292-305
Technical Paper | doi.org/10.13182/NSE77-A27041
Articles are hosted by Taylor and Francis Online.
The thermal-neutron behavior in a highly heterogeneous cluster-type plutonium fuel lattice has been studied through the measurements of the dysprosium reaction-rate distribution in a unit cell covering three plutonium fuel elements, four coolant voids, and two lattice pitches. The study included comparison with the results obtained with UO2 fuel. A new technique for locating the foils has been developed, resulting in an accurate measurement of the thermal-neutron flux distribution. Depression of the thermal-neutron flux in the fuel region is larger in the plutonium fuel lattice than in the uranium lattice because thermal-neutron absorption in the plutonium fuel is enhanced by the resonances of 239Pu and 241Pu at 0.3 eV. In addition, the 1/v cross section of plutonium is larger than that of uranium. This property of the plutonium fuel appears markedly at 100% void fraction, but less at 0% because this property is weakened by the presence of H2O coolant. The results of calculations obtained by means of the LAMP-DCA code showed good agreement with experimentally determined data within 5%.
