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Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
Georgeta Radulescu, Katherine E. Royston, Stephen C. Wilson, Walter Van Hove, David E. Williamson, Seokho H. Kim
Fusion Science and Technology | Volume 75 | Number 6 | August 2019 | Pages 452-457
Technical Paper | doi.org/10.1080/15361055.2019.1589205
Articles are hosted by Taylor and Francis Online.
Heat generated in the ITER fusion reactor is deposited in the tokamak vacuum vessel, in-vessel components, and in the components of the neutral beam injector during plasma operations and during subsequent decay of activation products. This heat is managed by the tokamak cooling water system (TCWS). The stainless steel material in the integrated loop of blanket edge-localized mode vertical stabilization coils and divertor (IBED) components (e.g., piping, heat exchangers (HXs), and pumps) contains activation sources because of its exposure primarily to neutron radiation from the decay of 17N, which is a short-lived radionuclide produced by neutron capture reactions with oxygen nuclei in the IBED primary heat transfer system (PHTS) cooling water during plasma operations. A detailed geometry model of the IBED stainless steel components and neutron radiation sources is required for an accurate assessment of the gamma activation sources on level 3 of the tokamak building. In the baseline design, each of the eight IBED PHTS cooling trains has two shell-and-tube heat exchangers (HXs) connected in series. Because these HXs are very large and contain a large amount of radioactive water, the possibility of using compact HXs of the welded shell-and-plate type is under investigation. This paper presents two Monte Carlo N-Particle (MCNP) TCWS geometry models, one model for each HX type, along with the associated piping. These models were obtained by automatic geometry conversion from TCWS computer-aided design models. The TCWS geometry models and neutron source definitions were incorporated into a baseline MCNP model of the Tokamak Complex.