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Watanabe, Tadashi
Proceedings of 11th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-11) (CD-ROM), 8 Pages, 2005/10
no abstracts in English
Fujita, Ayumi
Physical Review B, 64(6), p.064504_1 - 064504_6, 2001/08
Times Cited Count:0 Percentile:0(Materials Science, Multidisciplinary)We study parametric level statistics of the discretized excitation spectra inside a moving vortex core in layered superconductors with impurities. The universal conductivity is evaluated numerically for the various values of rescaled vortex velocities from the clean case to the dirty limit case. The random matrix theoretical prediction is verified numerically in the large regime. On the contrary in the low velocity regime, we observe which is consistent with the theoretical result for the super-clean case, where the energy dissipation is due to the Landau-Zener transition which takes place at the points called ``avoided crossing''.
Yokoi, Shinobu*; Yamamoto, Tomohiko; Miyazaki, Masashi; Tanaka, Masaaki; Yamane, Yuma*; Nishiwaki, Yoshinori*; Sago, Hiromi*; Morita, Hideyuki*; Iwasaki, Akihisa*; Ikesue, Shunichi*
no journal, ,
The design basis ground motions have been revised to improve the seismic resistance of nuclear power plants. The reduction of seismic forces not only horizontally but also vertically has required more critical than in the past to ensure the seismic resistance of components. Notably, the design of a Sodium-Cooled Fast Reactor will require reducing the seismic forces applied to the components because of the components with thin wall thickness. To overcome this problem, the authors plan to introduce a seismic isolation system. When the sloshing wave height is small, it can be approximated with a linear vibration model. However, when the sloshing wave height increases and the sloshing becomes nonlinear, it is necessary to evaluate the wave height using other methods such as numerical analysis. Although the evaluation of nonlinear sloshing wave height is important, there are few examples which quantitatively evaluate the wave height of nonlinear sloshing. This paper reports on the development plan and an overview of the evaluation method for nonlinear sloshing wave height and load applied to cylindrical tanks.
Ikesue, Shunichi*; Yamamoto, Tomohiko; Miyazaki, Masashi; Tanaka, Masaaki; Yokoi, Shinobu*; Sago, Hiromi*; Morita, Hideyuki*
no journal, ,
The design basis ground motions have been revised to improve the seismic resistance of nuclear power plants. The reduction of seismic forces not only horizontally but also vertically has required more critical than in the past to ensure the seismic resistance of components. Notably, the design of a Sodium-Cooled Fast Reactor will require reducing the seismic forces applied to the components because of the components with thin wall thickness. To overcome this problem, the authors plan to introduce a seismic isolation system. However, the natural frequency of first order sloshing may be close to the response frequency of the Sodium-Cooled Fast Reactor with the seismic isolation system, and the sloshing wave height is expected to increase. When the sloshing wave height increases, the sloshing becomes the nonlinear sloshing, which can't be evaluated by linear sloshing theory. In order to evaluate the sloshing loads, which act on the roof and the internal structure, the nonlinear sloshing liquid surface shape and the nonlinear sloshing flow velocity are necessary. Therefore, the authors studied the predictive evaluation method of the nonlinear sloshing for the liquid surface shape and the flow velocity with simplified equations. This paper reports on an overview of this predictive evaluation method.