ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Nuclear Technology
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Latest News
ARPA-E announces $40 million to develop transmutation technologies for UNF
The Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E) announced $40 million in funding to develop cutting-edge technologies to enable the transmutation of used nuclear fuel into less-radioactive substances. According to ARPA-E, the new initiative addresses one of the agency’s core goals as outlined by Congress: to provide transformative solutions to improve the management, cleanup, and disposal of radioactive waste and spent nuclear fuel.
Phillip M. Gorman, Jasmina L. Vujic, Ehud Greenspan
Nuclear Technology | Volume 191 | Number 3 | September 2015 | Pages 282-294
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT14-106
Articles are hosted by Taylor and Francis Online.
This study searches for the optimal fuel assembly design for the RBWR-Th core, which is a reduced-moderation boiling water reactor that is fuel-self-sustaining. Except for the initial fuel loading, it is charged with only fertile fuel and discharges only fission products, recycling all actinides. The RBWR-Th is a variant of the RBWR-AC core proposed by Hitachi, which arranges its fuel in a hexagonal tight lattice, has a high outlet void fraction, axially segregates seed and blanket regions, and fits within the advanced boiling water reactor (ABWR) pressure vessel. The RBWR-Th shares these characteristics but replaces depleted uranium (DU) with thoria as the primary fertile fuel, eliminates the internal blanket while elongating the seed region, and eliminates absorbers from the axial reflectors.
The sensitivity of important RBWR-Th core performance parameters to change in each one of a dozen design variables was established. These sensitivities provide useful insight and guidance to search for the optimal core design. The design variables of the sensitivity studies include the length of the seed and blanket zones, fuel rod diameter, lattice pitch, number of pins per assembly, concentration distribution of the recycled transfertile (transuranium + transthorium) isotopes in the seed, amount of DU in the seed makeup, coolant mass flow rate, and simulated depletion cycle length. The performance of the RBWR-Th core was found to be highly sensitive to the pitch-to-diameter ratio and to modeling assumptions. Using the conservative modeling assumptions, it was not possible to get the full ABWR power level without exceeding the pressure drop constraint.