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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Deep geologic repository progress—2025 Update
Editor's note: This article has was originally published in November 2023. It has been updated with new information as of June 2025.
Outside my office, there is a display case filled with rock samples from all over the world. It contains a disk of translucent, orange salt from the Waste Isolation Pilot Plant near Carlsbad, N.M.; a core of white-and-bronze gneiss from the site of the future deep geologic repository in Eurajoki, Finland; several angular chunks of fine-grained, gray claystone from the underground research laboratory at Bure, France; and a piece of coarse-grained granite from the underground research tunnel in Daejeon, South Korea.
T.F. Yang, G.S. Luan,† L. Bromberg, D.R. Cohn, B.J. Braams
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 857-863
Advanced Reactor | doi.org/10.13182/FST91-A29452
Articles are hosted by Taylor and Francis Online.
A novel gaseous divertor concept is proposed consisting of gas chamber and pumping at high pressure or by reionizing the neutrals. The concept results in substantial reductions of the plasma temperature and heat flux at the target and the pumping requirement. Fluid model simulations of the scrape-off region of the Aries Reactor design by feeding the gas at the target at a flux of 1 × 1023m−2/s at 0.5 eV has shown that the electron and ion temperatures can be cooled to 20 eV. The heat flux to the target can be reduced from 80 MW/m2 to 6 MW/m2. The plasma temperature and heat flux at the divertor target are monotonically decreasing functions of the neutral incident flux. Interestingly the temperature and the heat flux also decrease with decreasing neutral gas initial flowing speed removing the need of gas jets. The backflow problem can be minimized by including a baffle plate to form a gaseous chamber. Monte-Carlo simulations using test particles have showed that the throat of the gaseous chamber can be practically plugged by the incident plasma to prevent backflow of neutrals into plasma core. The pumping can be facilitated by either operating the divertor chamber at high pressure on the order of 30 torr or reionizing the neutrals traveling to a weak toroidal field region.