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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.
Glen R. Longhurst, Alex Kratville
Fusion Science and Technology | Volume 66 | Number 3 | November 2014 | Pages 385-393
Technical Paper | doi.org/10.13182/FST14-801
Articles are hosted by Taylor and Francis Online.
A simple laboratory experiment was constructed to demonstrate in a classroom setting hydrogen permeation under conditions typical of some nuclear applications. The goal was to allow students to find both solubility and diffusivity parameters for hydrogen moving through commercial stainless steel tubing. The purpose of the present work is to compare test results from this laboratory experiment with results from others to validate the experiment. Hydrogen mixed with argon was admitted to a heated test chamber containing a coiled Type 316 stainless steel tube. Pure argon sweep gas was passed through the tube to a process-gas mass spectrometer where composition transients of pertinent gas species were recorded. Fits of a theoretical transient model to the experimental data gave values of both diffusivity and solubility of hydrogen in the stainless steel tube. Tests were conducted at hydrogen partial pressures ranging from 1.7 to 83 kPa and tube temperatures from 636 to 770 K. The form of the permeation transient data was fit well by a classical theoretical model. Observed values of diffusivity and solubility of hydrogen in the stainless steel from these transients were similar to literature values with some notable differences. Evidence of permeation delay due to interference by the diluting Ar was observed. Limitations of the experimental system are discussed.