JOPSS - Search Results

Journal Articles

Some characteristics of gas-liquid two-phase flow in vertical large-diameter channels

Shen, X.*; Schlegel, J. P.*; Hibiki, Takashi*; Nakamura, Hideo

Nuclear Engineering and Design, 333, p.87 - 98, 2018/07

https://doi.org/10.1016/j.nucengdes.2018.04.001

Times Cited Count：12 Percentile：30.77(Nuclear Science & Technology)

Journal Articles

Multi-dimensional gas-liquid two-phase flow in vertical large-diameter channels

Shen, X.*; Schlegel, J. P.*; Hibiki, Takashi*; Nakamura, Hideo

Proceedings of 2017 Japan-US Seminar on Two-Phase Flow Dynamics (JUS 2017), 6 Pages, 2017/06

JAEA Reports

Study on crystalline rock aiming at evaluation method of long-term behavior of rock mass (FY2015) (Contract research)

Fukui, Katsunori*; Hashiba, Kimihiro*; Matsui, Hiroya; Kuwabara, Kazumichi; Ozaki, Yusuke

JAEA-Research 2016-014, 52 Pages, 2016/09

JAEA-Research-2016-014.pdf:7.19MB

With respect to high-level radioactive waste disposal, knowledge of the long-term mechanical stability of shafts and galleries excavated in rock is required, not only during construction and operation but also over a period of thousands of years after closure. On the other hand, it is known that rock and the rock mass surrounding the disposal gallery shows time dependent behavior such as creep or the stress-relaxation. It becomes the issue in the stability evaluation of the disposal gallery to grasp the behavior. In order to solve this issue, we pushed forward research development. we pushed forward research development. In the fiscal year of 2015, the creep testing machine for Tage tuff was moved to the new building. The creep test was continuously conducted and the total testing time exceeded 17 years. The testing equipment and procedure were examined to investigate the deformation, failure and time-dependency of rock under wet conditions and between room temperature and 100 $^{circ}$ C. The long-term strength of rock under triaxle stress state was researched with the aid of laboratory testing results and in situ stress measurement.

Journal Articles

Identification of material constants in constitutive equation by indentation test with different indenters

Wakui, Takashi*; Futakawa, Masatoshi; Tanabe, Yuji*; Ioka, Ikuo

Zairyo, 51(6), p.681 - 687, 2002/06

https://doi.org/10.2472/jsms.51.681

This paper describes the novel technique for determining constants in constitutive equaution of elastic-palstic materials by the indentation test with indenters having different tip angles. FEM analyses were carried out to evaluate the effect of material constants and the indenter tip angle on the load-depth curve. The constitutive equation was determeined from the characterized curves associated with the effects on the slope. Simiulation analyses were performed for some material models to exammine accuracy of the presented technique. It is confirmed that this technique is useful to determine the constitutive equation of sub-surface of materials or coatings.

Journal Articles

Identification of the constitutive equation by the indentation technique using plural indenters with different apex angles

Futakawa, Masatoshi; Wakui, Takashi*; Tanabe, Yuji*; Ioka, Ikuo

Journal of Materials Research, 16(8), p.2283 - 2292, 2001/08

no abstracts in English

Journal Articles

Inelastic constitutive equation in Alloy800H

Kaji, Yoshiyuki; Kikuchi, Kenji; Penkalla, H. J.*

Proceedings of the 7th International Conference on Creep and Fatigue at Elevated Temperatures (CREEP7), p.179 - 183, 2001/06

A creep constitutive equation in Alloy800H was developed at 700, 800 and 850oC. In the equation, the inelastic strain rate is written in the form of a flow equation of the Norton-Bailey type and the hardening during deformation under various loads is induced by an internal stress which is subdivided into back stress and friction stress. The back stress represents a conservative part of the creep resistance while the friction stress includes all the dissipative parts in the internal structure such as grain boundary sliding, diffusion and interaction between dislocation and precipitation. Parameters were determined by the deformation properties for creep under constant stress conditions at each temperature. Deformation analyses show a good agreement between calculations and experimental results for creep tests at each temperature.

JAEA Reports