One-step Monte Carlo Global Homogenization Based on RMC code

다국어 초록 (Multilingual Abstract)

Due to the limitation of the computers, the conventional homogenization method is based on manyassumptions and approximations, and some tough problems such as energy spectrum and boundarycondition are faced. To deal with those problems, the Monte Carlo global homogenization is adopted. TheReactor Monte Carlo code RMC is used to study the global homogenization method, and the one-stepglobal homogenization method is proposed. The superimposed mesh geometry is also used to dividethe physical models, leading to better geometric flexibility. A set of multigroup homogenization crosssections is online generated for each mesh under the real neutron energy spectrum and boundarycondition, the cross sections are adjusted by the superhomogenization method, and no leakagecorrection is required. During the process of superhomogenization, the author-developed reactor coreprogram NLSP3 is used for global calculation, so the global flux distribution and equivalent homogenizationcross sections could be solved simultaneously. Meanwhile, the calculated homogenization crosssection could accurately reconstruct the non-homogenization flux distribution and could also be used forfine calculation. This one-step global homogenization method was tested by a PWR assembly and a smallreactor model, and the results show the validity.

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