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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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UM conducts molten salt experiment
For 2,300 hours, the molten salt pump Shaft Seal Test Facility (SSTF) operated at the University of Michigan’s Thermal Hydraulics Laboratory, according to an article from UM. The large-scale experiment was designed to evaluate shaft seal performance in high-temperature pump systems. Fewer than 10 facilities worldwide have successfully operated fluoride or chloride salts for more than 100 hours using over 10 kilograms of material.
E.A. Straker
Nuclear Science and Engineering | Volume 46 | Number 3 | December 1971 | Pages 334-355
Technical Paper | doi.org/10.13182/NSE71-A22371
Articles are hosted by Taylor and Francis Online.
Calculations have been made of the space, energy, angle, and time dependence of the neutron and secondary gamma-ray fields produced in the atmosphere by several neutron sources, and the results for a 12.2- to 15-MeV source and a fission source are compared in this paper. They include steady-state and time-dependent results at ranges out to 1500 m for both an infinite air medium and an air-over-ground medium, the latter for source heights of 15 and 343 m. The data show that the neutron doses and dose rates from the 12.2- to 15-MeV source are higher than those from the fission source in all geometries and time intervals. While the secondary gamma-ray doses produced by the 12.2- to 15-MeV source also are higher than those produced by the fission source in all geometries, the secondary dose rates are higher only for times less than 10-3 sec, after which the dose rates from the two sources are comparable. The effects of the ground are to enhance both the neutrons and the secondary gamma rays at ranges close to the source and to act as an absorber at ranges far from the source. These effects decrease with increasing source height.
