JOPSS - Search Results

JAEA Reports

Water permeability test of rock specimen with natural fractures using high viscosity liquid

JNC TN8430 2001-006, 65 Pages, 2001/10

JNC-TN8430-2001-006.pdf:15.23MB

We had been conducted to study hydraulic permeability along fracture intersection by NETBLOCK system using natural rock specimen. Since the permeability of this rock specimen fracture is high, it was suggest that turbulent flow might be occurred in available range of measurement system. In case of turbulent flow, estimated permeability and fracture aperture from test data tend to be low. Therefore we should achieve laminar flow. This study was used the high viscosity liquid instead of water, and test conditions which could attain laminar flow with the rock specimen was examined. The rock specimen is granite rock, has natural Y-type fractures intersection. A solution of Methyl-cellulose is used as high viscosity liquid. Due to the high viscosity liquid, hydraulic head could be measured in the wide range, and high viscosity liquid improved the accuracy of measurement. Laminar flow could be achieved in the rock specimen by the high viscosity liquid over 0.1wt%.

JAEA Reports

Examination of hydraulic property of natural rock specimen

*; *;

JNC TN8430 2001-003, 64 Pages, 2001/03

JNC-TN8430-2001-003.pdf:10.04MB

Handling methods and test conditions of hydraulic tests for NETBLOCK system had been examined by using acrylic and/or artificial rock specimen. A natural rock specimen (granite : excavated from Kamaishi mine) with fracture intersection was formed into practicable size for NETBLOCK system. Recently, we conducted a series of hydraulic test, in order to study the influence of fracture intersection by using the natural rock specimen. Hydraulic tests were conducted under several centimeters of head, which could be controlled by improved system because hydraulic permeability of target fractures were high. As a result, 10 $^{-4}$ 10 $^{-5}$ (m $^{2}$ /s) orders of hydraulic transmissivity of target fractures could be measured. A low permeability in the NW direction at the lower fracture was estimated from the heterogeneous head distribution. However, it is also expected that turbulence flow might be occurred under this study condition because fracture permeability is high and flow rate through the fracture is relatively high. In case of turbulence-flow, an estimated hydraulic transmissivity is low. High-viscosity fluid hydraulic test to achieve laminar flow will be needed for correcting an evaluated transmissivity.

Journal Articles

Creep motion in granular pile exhibiting steady surface flow

Komatsu, Teruhisa; Inagaki, Shio*; Nakagawa, Naoko*; Nasuno, Satoru*

Physical Review Letters, 86(9), p.1757 - 1760, 2001/02

https://doi.org/10.1103/PhysRevLett.86.1757

Times Cited Count：251 Percentile：97.52(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Experimental investigation on similarity between velocity and density profiles in density-scratified countercurrent flow in reactor horizontal leg

Shibamoto, Yasuteru; Yonomoto, Taisuke; Anoda, Yoshinari; Kukita, Yutaka*

Nuclear Engineering and Design, 201(1), p.83 - 98, 2000/09

https://doi.org/10.1016/S0029-5493(00)00264-8

Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

None

Okamoto, Koji*; *

JNC TY9400 2000-016, 90 Pages, 2000/06

JNC-TY9400-2000-016.pdf:2.53MB

no abstracts in English

JAEA Reports

Thermal-Hydraulic investigation on severaI fast reactor design concepts

Ohshima, Hiroyuki; Sakai, Takaaki; ; Yamaguchi, Akira; Nishi, Yoshihisa*; Ueda, Nobuyuki*; *

JNC TN9400 2000-077, 223 Pages, 1999/05

JNC-TN9400-2000-077.pdf:6.24MB

The feasibility study (Phase l) is being carried out at JNC to build up new design concepts of practical fast reactors (FRs) from the viewpoint of economy, safety, effective use of resources, reduction of environmental burden and non-proliferation. This report describes the results of the investigation, related to decay heat removal, core/fuel-assembly thermal-hydraulics and thermal-hydraulic correlations, that was performed in fiscal l999 as a part of the feasibility study. ln the study of the decay heat removal, the effects of several design parameters on the performance of the reactor vessel auxiliary cooling system (RVACS) in a middle-scale sodium-cooled FR were clarified by using a plant dynamic analysis code. The upper limit of RVACS performance was preliminarily estimated at approximately 0.50.6 MWe. Numerical methods for the plant dynamic analysis of gas-and heavy-metal-cooled FRs were also developed. They were applied to the preliminary calculations of the transition from scram to natural circulation and the transient characteristics in tentative plant design concepts were clarified. ln addition, a dimensionless number indicating natural circulation performance was deduced for the comparison of several plant design concepts. With respect to the core/fuel-assembly thermal-hydraulics, numerical analysis methods were improved for the pin-type fuel assembly of gas-and heavy-metal-cooled FRs, the coated-particle- type fuel assembly of helium-gas-cooled FR, and the ductless core of sodium-and heavy-metal-cooled FRs. As preliminary evaluations, thermal-hydraulics in the heavy-metal-cooled FR fuel assembly was compared with sodium-cooled one and thermal-hydraulic analyses of carbon-dioxide- and helium-gas-cooled FR fuel assemblies were performed. The analysis for the fuel assembly with inside duct of sodium-cooled FR was also carried out. The correlations of pressure loss and heat transfer coefficient were investigated for the thermal-hydraulic ...

JAEA Reports