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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.
James P. Blanchard, Carl Martin
Fusion Science and Technology | Volume 67 | Number 1 | January 2015 | Pages 158-166
Technical Paper | doi.org/10.13182/FST14-796
Articles are hosted by Taylor and Francis Online.
The ARIES team is currently proposing two tungsten divertor concepts for its tokamak designs and has performed extensive analyses to optimize their thermal and structural performance. Because of the high divertor operating temperatures and the low ductility of tungsten, thermal creep and fracture will be important failure mechanisms to consider. This paper presents a series of finite element analyses addressing the viable operating ranges of these tungsten plate divertor concepts with respect to creep and fracture. For fracture, the J-integral, a path-independent contour integral that estimates the strain energy release rate for a crack of assumed geometry, is used to address crack propagation. Elliptical surface cracks are introduced both inside and outside the coolant channel, and steady-state calculations are carried out for both full-power and cold shutdown conditions. It is determined that the critical crack is on the inside of the coolant channel with the highest stress intensities at full-power operation. Also, transient creep simulations are performed to predict the high-temperature thermal deformations and creep strains at various surface flux levels. Finally, transient thermal calculations are carried out to simulate edge-localized modes in the plasma, and conclusions are drawn with respect to the severity and frequency of these events with respect to surface melting for the two concepts.