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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.
Adrian S. Sabau, Kazutoshi Tokunaga, Michael G. Littleton, James O. Kiggans, Jr., Charles R. Schaich, Ralph B. Dinwiddie, Daniel T. Moore, Yoshio Ueda, Yutai Katoh
Fusion Science and Technology | Volume 75 | Number 7 | October 2019 | Pages 690-701
Technical Paper | doi.org/10.1080/15361055.2019.1623571
Articles are hosted by Taylor and Francis Online.
Assessing the effect of neutron irradiation of plasma-facing materials has been challenging due to both the technical and radiological challenges involved. In an effort to address the radiological challenges, a facility was developed to conduct high heat flux testing (HHFT) of inherently small samples of neutron-irradiated materials. A new line-focus reflector was designed and fabricated at Oak Ridge National Laboratory for a plasma-arc lamp (PAL) to attain a source heat flux of 12 MW/m2. The new reflector was fabricated with two ports for monitoring specimen condition during HHFT. At the same operational conditions for PAL, the absorbed heat flux in tungsten was increased from 1.39 MW/m2 with the uniform irradiance reflector to 5.12 MW/m2 for the line-focus reflector. This fourfold increase in the heat flux, at the same PAL electrode lifetimes, enabled cost-effective facility operation for a high number of cyclic high heat flux tests. Specifically, the test section is confined to a hemispherical dome, and specimens are bolted directly to a water-cooled copper alloy rod. Temperature measurement in the PAL facility was a main challenge due to a limited line of sight. For the first time in a PAL facility operating at high heat fluxes, the specimen surface temperature was directly measured during HHFT with a pyrometer. The HHFT data, which were obtained in this upgraded PAL facility, demonstrated the facility readiness for irradiated materials.