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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
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.