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LLNL, Ampera partner to develop thorium-based TRISO fuel
Lawrence Livermore National Laboratory has formed a strategic partnership with Ampera to develop the company’s nuclear fuel concept through a project named THUNDER, for Thorium Unimodal Droplet Ejection for Reactors.
The focus of THUNDER is fabricating TRISO made with kernels of thorium rather than the usual uranium. LLNL and Ampera will evaluate and optimize liquid metal–jetting technology to produce highly uniform, spherical kernels of thorium-232 for later processing into TRISO fuel.
R. A. Krakowski, R. L. Hagenson, G. E. Cort
Nuclear Technology | Volume 34 | Number 2 | July 1977 | Pages 217-241
Technical Paper | Reactor | doi.org/10.13182/NT77-A39699
Articles are hosted by Taylor and Francis Online.
The thermal-mechanical response of the Reference Theta-Pinch Reactor (RTPR) first wall was analyzed. The first wall problems anticipated for a pulsed, high-β fusion power plant can be ameliorated by either alterations in the physics operating point, materials reengineering, or blanket/first wall reconfiguration. Within the latter “configuration” scenario, a two-fold approach has been adopted for the thermal-mechanical portion of the RTPR first wall technology assessment. First, a number of new first wall configurations (bonded or unbonded laminated composites, all-ceramic structures, protective and/or sacrificial “bumpers”) were considered. Second, a more quantitative failure criterion, based on the developing theories of fracture mechanics, was identified. For each first wall configuration, transient heat transfer and thermoelastic stress calculations have been made. Two-dimensional finite element structural analyses have been made for a variety of mechanical boundary conditions. Only the Al2O3/Nb—1 Zr system has been considered. The results of this study indicated a wide range of design solutions to the pulsed thermal stress problem anticipated for the RTPR. The use of first wall bumpers, in particular, results in significant (a factor of ∼10) reduction in first wall thermal stresses, although simply reducing the insulator thickness also leads to acceptable stress levels. The means by which the first wall portion of the RTPR blanket segment is attached has a minor influence on the stress distribution, although more accurate two-dimensional thermal modeling of the first wall yields stresses that may be reduced by 40% of those predicted by the one-dimensional calculations used heretofore. Static fatigue life estimates of both all-ceramic and ceramic-metal first walls are in excess of five years for even the most severe conditions envisaged for the RTPR. Finally, relatively minor changes in the physics operating point were proven to reduce dramatically the RTPR first wall problem.