Three-dimensional numerical predictions on two-phase flow behavior in advanced light water reactors

Ose, Yasuo*; Takase, Kazuyuki; Yoshida, Hiroyuki; Kano, Takuma; Akimoto, Hajime

Dai-18-Kai Suchi Ryutai Rikigaku Shimpojiumu Koen Yoshishu (CD-ROM), 6 Pages, 2004/12

no abstracts in English

Persuit for new passive drag reducing surfaces

Akino, Norio

Haiteku Shimpojium Yamaguchi 2001 Teiko Gensho Seigyo Shimpojium Rombunshu, p.37 - 43, 2001/11

no abstracts in English

Study on subcooled-boiling flow in short-heated-length rectangular channels; Measurement of instantaneous void fraction using neutron radiography technique

Kureta, Masatoshi; Akimoto, Hajime

Konsoryu Shimpojiumu 2000 (Dai-19-Kai) Koen Rombunshu, p.59 - 60, 2000/00

no abstracts in English

Thermal striping; an experimental investigation on mixing of jets; Part III Remaining hydrodynamic results from initial experiments

Tokuhiro, Akira; Kimura, Nobuyuki;

JNC TN9400 2000-014, 86 Pages, 1999/06

JNC-TN9400-2000-014.pdf:11.72MB

Experiments were performed using the WAJECO facility to investigate the thermohydraulic mixing of multiple jets flowing out of a LMFBR core. Mixing is the root of the thermal striping problem. The multiple jets are typically at different velocities and temperatures and may induce thermal stresses upon components they impinge. In our study we modeled the mixing of three vertical jets, the central at a lower temperature than the two adjacent jets at equal temperatures. The jets are quasi-planar. The parameters were the average exit jet velocities (Uo,av) and the temperature difference between the "cold" and "hot" jets (Thc=Thot-Tcold). Measurements of the liquid velocity, initially using laser Doppler velocimetry (LDV) and later ultrasound Doppler velocimetry (UDV), for both our reference single-jet and the triple-jet configuration, comprised Phase I of the experiments (up to 1994). Two reports (TN9410 96-181 and TN9410 96-296; in Japanese) reported on the hydraulic and heat tra

Critical heat flux of subcooled flow boiling in narrow rectangular channels

Kureta, Masatoshi; Akimoto, Hajime

Proceedings of 7th International Conference on Nuclear Engineering (ICONE-7) (CD-ROM), 8 Pages, 1999/00

no abstracts in English

An Approach to Reconstruction of a Natural Crack using Signals of Eddy Current Testing, 1; Reconstruction of an Idealized Crack

JNC TN9400 99-009, 39 Pages, 1998/12

JNC-TN9400-99-009.pdf:1.12MB

In this paper, an approach to the reconstruction of an idealized natural crack of non-vanishing conductivity is proposed with use of signals of eddy current testing. Two numerical models are introduced at first for modeling a Stress Corrosion Crack (SCC) in order it possibly to be represented by a set of crack parameters. A method for rapid prediction of the eddy current testing signals arisen from these idealized cracks is given then by extending a knowledge based fast forward solver developed by authors to the case of a non-vanishing conductivity. On the other hand, the inverse algorithm of conjugate gradient method is improved to reconstruct the crack parameters and is implemented with the pick-up signals and gradients calculated by using the rapid forward solver. Several examples are presented finally for validating the proposed strategy. The results verified that both of the models can give reasonable reconstruction results in case of a low noise level. The model concerning the touch of crack surfaces with a conducting band region surrounded by the crack edge, however, is proved more efficient than the model using a conductivity distribution from the point of view of both reconstruction speed and accuracy.

Void fraction measurement with neutron radiography method for subcooled boiling two-phase flow in rectangular duct heated from one-side

Kureta, Masatoshi; Akimoto, Hajime

Dai-11-Kai Netsu Kogaku Shimpojiumu Koen Rombunshu, p.73 - 76, 1998/00

no abstracts in English

Experimental study on heat transfer augmentation for high heat flux removal in rib-roughened narrow channels

M.S.Islam*; Hino, Ryutaro; Haga, Katsuhiro; Monde, Masanori*; Sudo, Yukio

JAERI-Tech 97-032, 49 Pages, 1997/07

JAERI-Tech-97-032.pdf:1.53MB

no abstracts in English

Critical heat flux under conditions of high subcooling and high velocity at atmospheric pressure

Sudo, Yukio

Nihon Kikai Gakkai Rombunshu, B, 62(601), p.3376 - 3382, 1996/09

https://doi.org/10.1299/kikaib.62.3376

no abstracts in English

Numerical prediction of augmented turbulent heat transfer in an annular fuel channel with repeated two-dimensional square ribs

Takase, Kazuyuki

Nucl. Eng. Des., 165, p.225 - 237, 1996/00

https://doi.org/10.1016/0029-5493(95)01153-6

no abstracts in English