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Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Molten salt research is focus of ANS local section presentation
The American Nuclear Society’s Chicago–Great Lakes Local Section hosted a presentation on February 27 on developments at the molten salt research reactor at Abilene Christian University’s Nuclear Energy Experimental Testing (NEXT) Lab.
A recording of the presentation is available on the ANS website.
A. H. Spano
Nuclear Science and Engineering | Volume 19 | Number 2 | June 1964 | Pages 172-186
Technical Paper | doi.org/10.13182/NSE64-A28906
Articles are hosted by Taylor and Francis Online.
A calculational model for the Doppler reactivity feedback in a thermal, low-enrichment oxide core with non-uniform temperature distribution is derived on the basis of the UO2 resonance integral varying as the square root of the absolute temperature. An analytical solution of the prompt-approximation, space-independent neutron kinetic equation, with the Doppler feedback written as a function of the fission energy, is obtained and application made to the self-limiting power-excursion tests conducted in the SPERT I oxide core. Comparison of the experimental and calculated Doppler effects, peak powers, burst energies and burst shapes is made for various published values of the UO2 resonance integral temperature coefficient, which acts as a scaling factor in the calculations. The values used cover a spread of about 20% of the mean value, and excellent agreement with experiment is obtained for the smallest values of the coefficient. Systematic agreement is obtained between the calculated and experimental Doppler effects over the entire experimental range of adiabatic fuel-temperature rises attained in the short-period SPERT tests. This agreement implies the validity of a square-root temperature dependence for the Doppler effect in a thermal oxide core, in contrast with a logarithmic or a T 1/2 dependence, for which similar calculations give results which differ significantly from the experimental data.