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Latest News
UIUC submits MMR construction permit application
The University of Illinois–Urbana-Champaign, in partnership with Nano Nuclear Energy, has submitted a construction permit application to the Nuclear Regulatory Commission for construction of a Kronos micro modular reactor (MMR). This is the first major step in the two-part 10 CFR Part 50 licensing process for the research and test reactor and is the culmination of years of technical refinement and regulatory alignment.
The team chose to engage with the NRC in a preapplication readiness assessment, providing the agency with draft versions of the majority of the CPA’s technical content for feedback, which is expected to ensure a high-quality application.
Hiroshi Nakashima, Shun-Ichi Tanaka, Tomoo Suzuki
Fusion Science and Technology | Volume 16 | Number 3 | November 1989 | Pages 365-376
Technical Paper | Shielding | doi.org/10.13182/FST89-A29127
Articles are hosted by Taylor and Francis Online.
An experiment was carried out to study the behavior of 14-MeV neutrons incident to a large cavity composed of mortar coated with stainless steel, which simulates a neutral beam injector (NBI) in a tokamak fusion reactor. Fast neutron spectra and reaction rate distributions were measured inside the cavity with a 5.06-cm-high × 5.06-cm-diam NE-213 spectrometer as well as 232Th and 235U fission counters. The experimental results were analyzed with a Monte Carlo MCNP-3 code, using nuclear data files from the JENDL series and from ENDF/B-IV. Calculations with two discrete ordinates codes, DOT3.5 and BERMUDA-2DN, using ENDF/B-IV and JENDL nuclear data files, were also compared with the measurements to study their applicability for NBI design. For fast neutrons, the MCNP calculations are in good agreement with the measurements. Moreover, comparison between the DOT3.5 and BERMUDA-2DN calculations showed the significant effect of the Legendre expansion of neutron scattering in the high-energy region. For low-energy neutrons, the DOT3.5 code calculations agreed with the measurements, while the MCNP code could not successfully reproduce the measurements. The experiments also suggested that the ratios of thermal and epithermal neutrons were constant for the 14-MeV neutrons coming into the cavity.
