Discussion of the numerical reproduction of the Ishii-Grolmes experimental correlation

Ebihara, Kenichi; Watanabe, Tadashi

Dai-18-Kai Suchi Ryutai Rikigaku Shimpojiumu Koen Yoshishu (CD-ROM), 7 Pages, 2004/12

The Ishii-Grolmes experimental correlation, which represents the inception criteria of the droplet entrainment, has been reproduced by the lattice Boltzmann simulation[Ebihara et al., Nagare 23, 253(2004)]. It has been observed in the simulation that the droplet broke off the wave which was generated on the smooth interface of the horizontal stratified two-phase flow. The numerical and physical influence on the reproduction of the experimental correlation is discussed in this paper. It is verified that the lattice size was enough for the reproduction of the experimental correlation though the discretization of the lattice affects the simulation result numerically. It is also seen that the shape of the generated wave and the flow velocity distribution affect the simulation results as the physical influence.

Critical power in axially uniformly-heated tight-lattice rod bundles

Kureta, Masatoshi; Akimoto, Hajime

Nihon Kikai Gakkai Rombunshu, B, 69(682), p.1469 - 1476, 2003/06

https://doi.org/10.1299/kikaib.69.1469

no abstracts in English

A feasibility study of the particle interaction method for the flow regimes with the chemical reaction; (Report under the contract between JNC and Toshiba Corporation)

Shirakawa, Noriyuki*; *; *; *

JNC TJ9440 2000-008, 47 Pages, 2000/03

JNC-TJ9440-2000-008.pdf:1.96MB

The numerical thermohydraulic analysis of a LMFR component should involve its whole boundaly in order to evaluate the effect of chemical reaction within it. Therefore, it becomes difficult mainly due to computing time to adopt microscopic approach for the chemical reaction directly. Thus, the thermohydraulic code is required to model the chemically reactive fluid dynamics with constitutive correlations. The reaction rate denpends on the binary contact areas between components such as continuous liquids, droplets, solid particles, and bubbles. The contact areas change sharply according to the interface state between components. Since no experiments to study the jet flow with sodium-water chemical reaction have been done, the goal of this study is to obtain the knowledge of flow regimes and contact areas by analyzing the fluid dynamics of multi-pahse and reactive components mechanistically with the particle interaction method. For the first stage of the study, the applicability of this method to the nalysis of a liquid jet into the other liquid pool was investigated. Based on the literatures, we investigated the jet flow mechanisms and analyzed the experiment of a water jet into a gasoline pool. We also analyzed SWAT3/Run19 test, the jet flow in a rod bundle, to study the applicability of the method to a complicated boundary without a chemical reaction model. The calculated fluid dynamics was in good agreement with the experiment. Furthermore, we studied and formulated the paths of phase change and chemical reaction, and conceptually designed the adopting the heat-transfer-limited phase change model and the synthesizd reaction model with a water-hydrogen conversion ratio.

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 ...

None

PNC TN1410 97-034, 338 Pages, 1997/09

PNC-TN1410-97-034.pdf:6.65MB

no abstracts in English

Thermal and hydraulic performances of fuel rods with transverse square ribs in HTTR

Takase, Kazuyuki; Hino, Ryutaro;

Nihon Genshiryoku Gakkai-Shi, 35(11), p.996 - 998, 1993/11

https://doi.org/10.3327/jaesj.35.996

no abstracts in English

Two-phase flow characteristics analysis code: MINCS

Watanabe, Tadashi; Hirano, Masashi; ; Tanabe, Fumiya; Kosaka, Atsuo

JAERI 1326, 232 Pages, 1992/03

JAERI-1326.pdf:4.82MB

no abstracts in English

Void fractions under high-pressure boil-off conditions in rod bundle

; Kumamaru, Hiroshige; Watanabe, Tadashi; Anoda, Yoshinari; Kukita, Yutaka

ANS Proc. 1991 National Heat Transfer Conf., Vol. 5, p.225 - 232, 1991/00

no abstracts in English

Development of assessment method to evaluate the material relocation behavior in the core disruptive accident of FBR, 10; Predictive evaluation method of the distance for fragmentation of molten core material

Matsuba, Kenichi; Isozaki, Mikio; Kamiyama, Kenji; Tobita, Yoshiharu

no journal, , 

In order to develop an evaluation method of the distance for fragmentation of molten core material discharged into the lower sodium plenum during core disruptive accidents in sodium-cooled fast reactors, a series of experiments on fragmentation behavior of simulated molten materials was carried out. A semi-empirical correlation of the distance for fragmentation was developed from the experimental results.