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Urenco USA marks enrichment milestones
Urenco USA has highlighted the completion of a successful year of advancing nuclear fuel supply in the U.S. by achieving two new milestones this month: The first production of enriched uranium above 5 percent uranium-235, and the startup of the company’s next cascade of centrifuges as part of its capacity installation program.
Hiroki Takezawa, Toru Obara
Nuclear Science and Engineering | Volume 164 | Number 1 | January 2010 | Pages 80-86
Technical Note | doi.org/10.13182/NSE08-91
Articles are hosted by Taylor and Francis Online.
The integral kinetic model is applicable to space-dependent kinetic analysis for any weakly coupled system because of its applicability to any geometry. Transient parameters that describe the time distribution of neutron transport between regions in a system are essential for this model. This paper presents a formula for calculating the parameters based on the nonanalog Monte Carlo neutron transport simulation technique. A continuous-energy Monte Carlo code MVP2.0 was modified to calculate the parameters, and the modification was verified using the static coupled reactor theory. The parameters were calculated in a simple fast-thermal coupled reactor. The results showed a difference in fission starting times between a fast region and a thermal region, which can cause a time lag in the transient behavior between the two regions. The results also revealed the time distribution of neutron energy groups that trigger fissions in each region. A space-dependent kinetic analysis code based on the integral kinetic model is under development, and these parameters can be used in the integral kinetic model to perform space-dependent kinetic analysis for weakly coupled systems.