Project/Area Number |
02452290
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
Nuclear engineering
|
Research Institution | The University of Tokyo |
Principal Investigator |
SUZUKI Atsuyuki The University of Tokyo, Faculty of Engineering, Professor, 工学部, 教授 (50011135)
|
Co-Investigator(Kenkyū-buntansha) |
OKAMOTO Tsuyoshi The University of Tokyo, Faculty of Engineering, Technical Official, 工学部, 教務職員 (40114425)
AHN Joonhong The University of Tokyo, Faculty of Engineering, Lecturer, 工学部, 講師 (10201906)
|
Project Period (FY) |
1990 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥4,800,000 (Direct Cost: ¥4,800,000)
Fiscal Year 1992: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1991: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1990: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
Keywords | Radioactive Waste Management / Geologic Disposal / Fracture Network / Percolation Theory / Disordered Media / Dispersion / Monte Carlo Simulation / 不規則媒体 / 分散 / 亀裂ネットワ-ク / ニア・フィ-ルド / パ-コレ-ション理論 / 拡散 / ランダム・ウォ-ク・シミュレ-ション |
Research Abstract |
Anomalous diffusion on 2-dimensional, or 3-dimensional percolation clusters were analysed by the exact enumeration method, and a generalized formulation for anomalous diffuion in terms of anomalous diffusion exponent, fractal and fracton dimensions was established. By this formulation normal Fickian diffusion can also be expressed as a special case. Mass transport in randomly-distributed lines in a 2-dimensional space, which is considered as a simulation of geological fracture networks, was analyzed both experimentally and computationally, to investigate effects of flow in a network. In the experimental work, random-line networks were realized on photosensitive resin. Analysis of breakthrough curves reveals that dispersivity is equal to correlation length of random-line networks, and that networks of less connectivity indicates greater correlation length or dispersivity. Correlation length of well-connected networks is roughly in the same order as the length of lines distributed. In the computational work, tracer dispersion in the random-line network was simulated by the Monte Carlo method. Molecular diffusion of tracers into dead-end pores and low-flow regions in networks is found to be the key mechanism of non-Fickian behavior of tracer dispersion. Characteristic length of electrical conductivity and permeability of porous media made by consolidating glass beads can be predicted by the original radius distribution of glass beads.
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