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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
Denver Airport may go nuclear
Colorado’s first nuclear power plant of the 21st century could be built at an unconventional site: the Denver International Airport (DEN).
In its mission to gain energy independence and become the greenest airport in the world, DEN has announced that it will conduct a feasibility study to determine the viability of building a small modular reactor on its 33,500-acre campus.
Argala Srivastava, K. P. Singh, S. B. Degweker
Nuclear Science and Engineering | Volume 189 | Number 2 | February 2018 | Pages 152-170
Technical Paper | doi.org/10.1080/00295639.2017.1388091
Articles are hosted by Taylor and Francis Online.
The use of the Monte Carlo (MC) method for space-time reactor kinetics is expected to be much more accurate than the presently used deterministic methods largely based on few-group diffusion theory. However, the development of the MC method for space-time reactor kinetics poses challenges because of the vastly different timescales of neutrons and delayed neutron precursors and their vastly different populations that also change with time by several orders of magnitude. In order to meet these challenges in MC-based space kinetics, we propose various new schemes such as deterministic decay of precursors in each time step, adjustment of weights of neutrons and precursors for population control, use of mean number of secondaries per collision, and particle splitting/Russian roulette to reduce the variance in neutron power. The efficacy of these measures is first tested in a simpler point-kinetics version of the MC method against analytical or accurate numerical solutions of point-kinetics equations. The ideas are then extended to space-dependent MC kinetics and are validated against a transport theory/MC transient benchmark. We have also tested our methods by comparison with results of realistic space-time kinetics benchmarks/studies involving multiregion reactors, energy dependence, movement of control rods, and feedback—most of which are based on few-group diffusion theory treated by the finite difference method. To facilitate exact comparison with such benchmarks, we have implemented the schemes described above for space-time reactor kinetics based on finite difference diffusion MC, a method developed by us earlier in a different context.