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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.
Charles W. Bagnal, Jr., Gerard P. Cavanaugh, Robert P. Harris, Regis A. Matzie, Laszlo B. Tarko
Nuclear Technology | Volume 68 | Number 1 | January 1985 | Pages 7-17
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33562
Articles are hosted by Taylor and Francis Online.
Fuel management and core periphery modifications are examined for slowing pressurized water reactor (PWR) pressure vessel embrittlement by reducing the incident fast flux to the vessel Such strategies can help to mitigate the consequences of pressurized thermal shock, a current licensing concern. For most operating PWRs, a factor of 2 reduction in fast flux to the reactor vessel critical welds can be achieved with little or no penalty in power peaking (3% or less), which implies only a small degradation in thermal margin. This can be accomplished with low leakage fuel management, which places twice-burned fuel near these welds. To achieve higher reduction factors, materials with good fast neutron attenuation properties must be used in conjunction with low leakage fuel management. For example, a reduction factor of 3 implies a limited use of dummy stainless steel assemblies (with an associated increase in power peaking of at least 8%) or the use of stainless steel patches between the core and the vessel In general, a factor of 3 reduction in fast flux is a practical upper limit to what can be reasonably achieved without significant degradation of thermal margin. A factor of 5 reduction may be possible in some cases, but would require the liberal use of dummy assemblies and/or stainless steel patches; a fast flux reduction by a factor of >5 would most likely require power derating.