Literature survey of thermal-hydraulic studies on super-critical pressurized water

Kurihara, Ryoichi; Watanabe, Kenichi*; Konishi, Satoshi

JAERI-Review 2003-020, 37 Pages, 2003/07

JAERI-Review-2003-020.pdf:2.08MB

no abstracts in English

The Method for decrease of helium gas leak with double O-ring rubber gasket

Oba, Toshihiro; Kikuchi, Taiji; Taka, Isamu; Isozaki, Futoshi*; Chiba, Masaaki; Ishikawa, Kazuyoshi; Inoue, Hiromi*; Terunuma, Isao*; Sawabe, Masaki*; Tsuda, Kazumi*; et al.

JAERI-Tech 2001-067, 29 Pages, 2001/11

JAERI-Tech-2001-067.pdf:1.93MB

no abstracts in English

Mechanical integrity of floor liner in secondary heat transport system cells of Monju

; ; Ueno, Fumiyoshi; ; ; ;

JNC TN2400 2000-005, 103 Pages, 2000/12

JNC-TN2400-2000-005.pdf:3.98MB

Inelastic analyses of the floor liner subjected to thermal loading due to sodium leakage and combustion were carried out, considering thinning of the liner plate due to molten salt type corrosion. Because the inelastic strain obtained by the analyses stayed below the ductility limit of the material, mechanical integrity, i.e., there exist no through-wall crack on the floor liner, was confirmed. Partial structural model tests were conducted, with a band of local thinning of the liner plate. Displacements were controlled to give specimens much larger strains than those obtained by the inelastic analyses above. No through-wall crack was observed by these tests. Mechanical integrity of the floor liner was confirmed by these results of the inelastic analyses and the partial structural model tests.

Proposal of source term methodologies for mercury target system

Kobayashi, Kaoru*; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Kogawa, Hiroyuki; Hino, Ryutaro

JAERI-Tech 2000-050, 43 Pages, 2000/08

JAERI-Tech-2000-050.pdf:2.36MB

no abstracts in English

Study of safety aspects for pyrochemical reprocessing systems

Kakehi, Isao; Nakabayashi, Hiroki

JNC TN9400 2000-051, 237 Pages, 2000/04

JNC-TN9400-2000-051.pdf:8.14MB

In this study, we have proposed the concept of safety systems (solutions of safety problems) in pyrochemical reprocessing systems (lt consists of pyrochemical reprocessing methods and the injection casting process for the metal fuel fabrication, or vibro-packing process for the oxide fuel fabrication.) which has different concept from the existing PUREX reprocessing method and pellet fuel fabrication process. And we performed its safety evaluations. FoIlowing the present Japanese safety regulations for reprocessing facilities, we pointed out functions, design requirements and equipments relating to its safety systems and picked up subjects. For the survey of safety evaluations, we first selected anticipated events and accident events, and second by evaluated 6the correspondence of the limitation of the public exposure to the accidents above, by using two parameters, the safety design parameter (the filter performance to confine radioactive matelials) and the leak inventory of radioactivities, and last by picked up its problems. ln addition to the above evaluations we performed basic criticality analyses for its systems to utilize these results for the design and evaluation of the criticality safety management system. Thus this study specified the concept of safety systems for pyrochemical reprocessing processes and then issues in order to establish safety design policies (matters which must consider for the safety design) and guides and to advance more definite safety design.

Sodium combustion computer code ASSCOPS Version 2.1; User's manual

Ohno, Shuji; Matsuki, Takuo*; ; Miyake, Osamu

JNC TN9520 2000-001, 196 Pages, 2000/01

JNC-TN9520-2000-001.pdf:5.13MB

ASSCOPS (Analysis of Simultaneous Sodium Combustion in Pool and Spray) has been developed for analyses of thermal consequences of sodium leak and fire accidents in LMFBRs. This report presents a description of the computational models, input and output data as the user's manual of ASSCOPS version 2.1. ASSCOPS is an integrated computational code based on the sodium pool fire code SOFIRE II developed by the Atomics International Division of Rockwell International, and on the sodium spray fire code SPRAY developed by the Hanford Engineering Development Laboratory in the U.S. The users of ASSCOPS need to specify the sodium leak conditions (leak flow rate and temperature, etc.), the cell geometries (cell volume, surface area and thickness of structures, etc.), and the atmospheric initial conditions such as gas temperature, pressure, and composition. ASSCOPS calculates the time histories of atmospheric temperature, pressure and of structural temperature.

An experimental study of sodium aerosol detection sensitivity by laser induced breakdown spectroscopy

;

JNC TN9400 2000-020, 54 Pages, 1999/11

JNC-TN9400-2000-020.pdf:2.36MB

A Laser-induced breakdown spectroscopy Leak Detection technique (abbreviated LLD) of sodium is accomplished by plasmafying the sodium aerosol, and then selectively detecting the sodium specific optical spectrum. This method is potentially more reliable as a means of detecting of sodium small leakage. This report, describes test results of detection characteristics using sodium aerosol, carried out to verify the principle of LLD in addition to evaluating the response under various conditions. 0ur main objective is to examine the applicability of LLD for small sodium leakage. The main results are as follows; (1)We confirmed the principle of LLD, specifically detecting the sodium optical spectru.m. (2)The relation between LLD fluorescence intensity and sodium aerosol concentration is nearly proportional within a relatively Na concentration ranges 10 10 g/cm. (3)The LLD signal appeared insensitive to the effect of sampling gas flow rate, oxygen concentration, and humidity in the examined range. ln fact, a high S/N ratio is obtained for small sodium leakage, and the reliability of the leakage detection is high, because LLD showed sensitive to sodium concentration. From these results and others discussed in this report, LLD appears to be an applicable technique in small leakage detection both in terms of response and reliabilily in the leakage phase.

Passive electromagnetic NED for mechanical damage inspection by detecting leakage magnetic flux, 1; Reconstruction of magnetic charges from detected field signals

; Aoto, Kazumi;

JNC TN9400 99-061, 32 Pages, 1999/07

JNC-TN9400-99-061.pdf:0.95MB

In this report, reconstruction of magnetic charges induced by mechanical damages in a test piece of SUS304 stainless steel is performed as a part of eforts to establish a passive nondestructive testing method on the basis of the inspection of leakage magnetic field. The approach for solving this typical ill-posed inverse problem is selected as a way in the least square method category. Concerning the ill-poseness of the system of equations, an iteration algorithm is adopted to its solving in which the designations of initial profile, the weight coefficients and the total number of iterations are taken as means of reqularization. From examples using simulated input data, it is verified that the approach gives good reconstruction results in case of signals with a relative high S/N ratio. For improving the robustness of the proposed method, a Galerkin procedure with base functions chosen as the Daubechies' wavelet is also introduced for discretizing the governing equation. By comparing the reconstruction results of the least square method and those using wavelet discretization, it is found that the wavelet used approach is more feasible in the inversion of noise polluted signals. Reconstruction of 1-D and 2-D magnetic charges with the least square strategy and reconstruction of an 1-D problem with the wavelet used method are carried out from both simulated and measured magnetic field signals which are used as the validation of the proposed inversion strategy.

PNC Technical Review No.107

PNC TN1340 98-003, 126 Pages, 1998/09

PNC-TN1340-98-003.pdf:17.88MB

no abstracts in English

Beamline performance of 500 keV negative ion-based NBI system for JT-60U

Ito, Takao;

Fusion Engineering and Design, 39-40, p.123 - 128, 1998/00

https://doi.org/10.1016/S0920-3796(97)00185-3

no abstracts in English