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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.
T. J. Carter
Nuclear Technology | Volume 45 | Number 2 | September 1979 | Pages 166-176
Technical Paper | Material | doi.org/10.13182/NT79-A32307
Articles are hosted by Taylor and Francis Online.
In the quest to reduce cladding strain from power ramps and thereby reduce the incidence of defects, various aspects of pellet geometry have been examined. The influence of pellet end squareness was investigated in steady-power irradiation of UO2 with end tapers well in excess of the currently allowable deviation from end squareness, and no increase in postirradiation cladding strains was noticeable. Five ramp tests were performed to examine the effects of pellet length-to-diameter ratio, the width of the loadbearing annulus (shoulder) at the dished end, and the effect of adding a small 45-deg edge chamfer. Although cladding strains were significantly reduced by changes in pellet geometry, there appears little incentive to do so from the viewpoint of preventing Zircaloy cracking, since defects occurred in rods that had lower overall strains than those that survived.