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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.
Gabriele Ferrero, Samuele Meschini, Raffaella Testoni
Fusion Science and Technology | Volume 78 | Number 8 | November 2022 | Pages 617-630
Technical Paper | doi.org/10.1080/15361055.2022.2096365
Articles are hosted by Taylor and Francis Online.
The Affordable, Robust, Compact (ARC) fusion reactor is a preconceptual design proposed by the Plasma Science and Fusion Center at the Massachusetts Institute of Technology that will be developed by Commonwealth Fusion Systems. ARC features a Li2BeF4 (FLiBe) molten salt liquid blanket that provides reactor cooling, neutron shielding, and tritium breeding. This work aims to develop a preliminary coupled computational fluid dynamics (CFD) and tritium transport model to describe FLiBe flow inside the tank and to assess ARC tritium inventory in the vacuum vessel and blanket. Both models are built by taking advantage of COMSOL® Multiphysics. FLiBe velocity and temperature fields are evaluated by the CFD models, and they are passed as input to the tritium transport model. The tritium transport model computes tritium concentration inside solid materials and FLiBe. An auxiliary FLiBe inlet has been moved from the original position in the ARC preconceptual design to improve blanket cooling and to reduce the size of flow eddies. Results show that many recirculation zones generate inside the tank for the chosen tank geometry, size, and inlet-outlet conditions. Larger FLiBe temperature and tritium concentration are found in these zones. The high FLiBe temperature in recirculation areas may not allow for effective cooling, and Inconel 718 reaches critical temperatures. The largest tritium concentration for a steady-state model with continuity of tritium partial pressure at the interfaces is found in Inconel 718 while the second-highest concentration is reached in FLiBe. The total tritium inventory in the ARC blanket with the assumed model is quantified as 3.16 g.