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Aalo Atomics achieves criticality on July 4
Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.
In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.
T. D. Bohm, M. E. Sawan, B. Smith, P. P. H. Wilson
Fusion Science and Technology | Volume 60 | Number 2 | August 2011 | Pages 698-702
Nuclear Analysis & Experiments | Proceedings of the Nineteenth Topical Meeting on the Technology of Fusion Energy (TOFE) (Part 2) | doi.org/10.13182/FST11-A12466
Articles are hosted by Taylor and Francis Online.
The ITER blanket modules (BM) are geometrically complex with many water coolant channels in a SS316 structure. Detailed mapping of nuclear heating, radiation damage, and helium production is an essential input to the design process. Previous high fidelity, high-resolution results calculated with the CAD based DAG-MCNP code revealed important heterogeneity effects on nuclear heating and helium production near steel/water interfaces. We carried out additional analysis for a simplified geometry to understand the reasons behind the observed peaking in the steel nuclear parameters at the interface with the water coolant. The results show that the peaking in nuclear heating is due to the softer neutron spectrum in the portion of steel adjacent to water which results in more gamma generation. Helium production peaking in steel adjacent to the water is due to the softer neutron spectrum which results in increased helium production primarily in B-10 impurities present in the SS316 in addition to a two-step reaction of low-energy neutrons with Ni.
