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In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
G. Kistner and J. T. Mihalczo
Nuclear Science and Engineering | Volume 35 | Number 1 | January 1969 | Pages 27-44
Technical Paper | doi.org/10.13182/NSE69-A21112
Articles are hosted by Taylor and Francis Online.
A series of static critical experiments has been performed on an accurate mockup of the SORA Reactor. SORA is a proposed NaK cooled, repetitively pulsed fast reactor which would be used as a high-intensity neutron source for time-of-flight experiments. The reactivity of this reactor is varied by a movable reflector. Those parameters which are related to the kinetics of the reactor have been investigated thoroughly in the critical experiments. They have been measured for both beryllium and iron reflectors of several sizes and for various core and fixed reflector configurations. The total reactivity of the movable reflectors varied from $3.7 for a 11.0-cm-wide iron reflector to $12 for a 26.2-cm-wide beryllium reflector. The reactivity of the movable reflector as a function of its position has been shown to have a parabolic dependence on position characterized by the parameter αx, which varied from 4 to 9.9¢/cm2. The prompt-neutron time decay is described by a fast decay constant which varied between 0.30 and 0.55/µ sec and a slow decay constant which varied between 0.05 and 0.10/µ sec. The critical mass for the various experiments was between 50.3 and 57.3 kg of uranium enriched to 93.2 wt% 235U. Using space-independent neutron kinetics with one delayed-neutron group, it has been shown that with a 24-cm-high × 7-cm-thick × 21-cm-wide beryllium reflector the assembly will produce 100 pulses/sec ∼50-µsec wide at half-maximum power with a peak-to-average power ratio of ∼180.