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Japan could replace up to 14 reactors by the 2050s under new proposal
Japan will need to replace as many as 14 of its nuclear reactors by the 2050s in order to meet its future energy demands, a recently released draft policy proposal states.
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.