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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).
R. D. McKnight
Nuclear Science and Engineering | Volume 75 | Number 1 | July 1980 | Pages 111-125
Technical Note | doi.org/10.13182/NSE80-A20322
Articles are hosted by Taylor and Francis Online.
A detailed validation study of the SDX fast reactor cell homogenization code, Benoist anisotropic diffusion coefficients, and an associated three-dimensional to one-dimensional unit cell modeling procedure has been in progress. These earlier results have investigated the standard zero power reactor (ZPR) plate-type unit cell The present study represents a complimentary validation effort for the ZPR pin calandria-type unit cell. The unit cell loading selected for this work consisted of a 5.08- × 5.08- × 30.48-cm voided calandria loaded with a 4 × 4 array of 0.957-cm (diam) × 15.24-cm mixed-oxide rods (15% PuO2/UO2). This unit cell was used in the pin zone measurements of the ZPR gas-cooled fast reactor program and also in the sodium-voided pin zone measurements of ZPR-6 Assembly 7. The validation effort consists of direct comparison with results of VIM (continuous energy Monte Carlo) calculations. The SDX/Gelbard methods have been shown to adequately predict both nonleakage and leakage effects for the voided pin calandria unit cell.
