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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.
B. Zhao, S. A. Musa, S. I. Abdel-Khalik, M. Yoda
Fusion Science and Technology | Volume 72 | Number 3 | October 2017 | Pages 300-305
Technical Paper | doi.org/10.1080/15361055.2017.1333828
Articles are hosted by Taylor and Francis Online.
The leading candidate for the DEMO divertor is the helium-cooled modular divertor with multiple jets (HEMJ) design, which is to date the only design that has been experimentally shown to accommodate incident steady-state heat fluxes greater than 10 MW/m2. In the HEMJ, the divertor target plates are cooled by 25 jets of different diameters that impinge upon a curved tungsten (W)-alloy surface brazed to a hexagonal W tile. Given the difficulties in manufacturing such a complicated geometry in W and W-alloys, numerical simulations were performed to determine if simplified versions of the HEMJ design could provide similar thermal-hydraulic performance. Parametric studies were performed at fully prototypical conditions using one-way coupled thermo-mechanical and fluid dynamics simulations in ANSYS® Workbench® to determine the effect of varying the jet-to-cooled surface distance, the number, diameter, and spacing of the jet holes (the jets were all assumed to have the same diameter), and the curvature of the cooled surface on the thermal-hydraulic performance. The results for the evaluated 75 different jet array configurations suggest that similar and even superior thermal-hydraulic performance can be provided by several designs. These HEMJ variants with fewer jets and larger holes may reduce fabrication costs and improve reliability. For example, the simulations suggest that a configuration involving flat surfaces with six holes surrounding one central hole, all with a diameter of 1.18 mm at a jet-to-cooled surface distance of 1.25 mm provides a 6.6% higher average heat transfer coefficient (HTC) at a 4.8% lower pressure drop when compared with the HEMJ. The maximum temperature of the outer shell and cooled surface stress are also lower for this design. In all cases, the simulations also suggest that the jet-to-cooled surface distance decreases by approximately 0.2 mm when the temperature increases from ambient to prototypical conditions due to differential thermal expansion of the jets cartridge and the W-alloy pressure boundary.