Volatilization of BC control rods in Fukushima Daiichi nuclear reactors during meltdown; B-Li isotopic signatures in cesium-rich microparticles

Fueda, Kazuki*; Takami, Ryu*; Minomo, Kenta*; Morooka, Kazuya*; Horie, Kenji*; Takehara, Mami*; Yamasaki, Shinya*; Saito, Takumi*; Shiotsu, Hiroyuki; Onuki, Toshihiko*; et al.

Journal of Hazardous Materials, 428, p.128214_1 - 128214_10, 2022/04

https://doi.org/10.1016/j.jhazmat.2022.128214

Experimental investigation of debris sedimentation behaviour on bed formation characteristics

Shamsuzzaman, M.*; Horie, Tatsuro*; Fuke, Fusata*; Kai, Takayuki*; Zhang, B.*; Matsumoto, Tatsuya*; Morita, Koji*; Tagami, Hirotaka; Suzuki, Toru; Tobita, Yoshiharu

Proceedings of 8th Japan-Korea Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS-8) (USB Flash Drive), 10 Pages, 2012/12

Investigation on sedimentation behavior of debris is important to evaluate the sequence of core disruptive accident in SFR. To clarify this behavior, a series of experiments was performed by gravity driven discharge of solid debris from a nozzle into a water pool. The discharged debris accumulates on the collector plate at the bottom, forming either a Gaussian-type convex or ring-type concave mound depending on the experiment parameters. Three types of spherical debris with three diameters are employed to study the effect of experiment parameters on mound height of debris bed. During the experiment, mound height becomes decreasing with nozzle diameter and increasing with debris volume, which exhibits descending tendency in asymmetrical fashion with density variation and an unalike variation in mound height was observed with debris diameter. An empirical model was developed applying dimensional analysis to predict the variation in mound height of debris bed during sedimentation process.

Evaluation of the correlation model for the contact areas concentration between sodium and steam with the particle interaction method

Horie, Hideki*; Yamamoto, Yuichi*; Oue, Masaya*; Shirakawa, Noriyuki*

JNC TJ9400 2005-007, 135 Pages, 2004/02

JNC-TJ9400-2005-007.pdf:7.19MB

In a LMFR steam generator, liquid sodium flows through the component vessel, which has a manifold of heat transfer tubes through which water or steam flows under very high pressure. If the water or steam is issued as a jet into sodium pool by the high pressure due to tube failure, sodium-water reaction occurs and affects the component integrity. The phenomena are strongly nonlinear processes in multi-phase flow. To evaluate contact areas concentration between fluid components is essential to analyze the phenomena. In this work, the correlation model for the contact areas concentration between two different liquids developed with the particle interaction method, which method is capable of evaluating the mixing layer between two kinds of fluid, was applied to a gasjet issued into a liquid pool to investigate its applicability. This investigation involves the analysis to consider the mole change of steam and generated gas due to the sodium-water chemical reaction and the analysis of the effect of a rod on the correlation model.

Analysis of the flow with sodium-water chemical reaction by the particle interaction method

Shirakawa, Noriyuki*; Horie, Hideki*; Yamamoto, Yuichi*

JNC TJ9400 2005-006, 183 Pages, 2002/02

JNC-TJ9400-2005-006.pdf:10.61MB

To evaluate the effect of accidents induced by sodium-water chemical reaction on a LMFR component, the numerical thermo-hydraulic analysis should involve the whole boundary of the component. Therefore, the thermo-hydraulic code is required to model the chemically reactive fluids dynamics with constitutive correlations.Both thermal and chemical reaction rate largely depends 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 experiment to investigate the jet flow with sodium-water chemical reaction has been done, the purpose of this study is to develop the evaluation method for flow regimes and contact areas by analyzing the fluid dynamics of multi-phase and reactive components mechanistically with the particle interaction method. In this fiscal year, following works were performed:(1) investigation to link the mesoscopic information of contact areas obtained by the particle interaction method with the macroscopic fluid dynamics code, (2) development of the correlation of contact areas, (3) investigation of the effect of the water-leak conditions on contact areas, and (4) analysis of contact areas for a slug flow.

Supplement to radiation shielding analysis of JOYO (C)

Kondo, Ryoichi*; Ozawa, Takeshi*; Horie, Junnosuke*; Handa, Hiroyuki*

PNC TJ202 82-03, 76 Pages, 1982/02

PNC-TJ202-82-03.pdf:1.43MB

A supplemental study on the JOYO's shielding analysis was performed focussing attention on the behavior of neutron and -ray fluxes around the detector guide tube of channel a and on the evaluation of the primary sodium activation with use made of the two-dimensional discrete ordinates transport code. It has been found out that secondary rays emitted from a thin guide tube material of SS-304 has a strong effect of enhancing gamma doserates in the guide tube penetrating through a graphite shielding. The effect of the guide tube penetrating a heavy concrete pedestal has been revealed to be a streaming of neutrons and gammas. It can be concluded that the effect of the detector guide tube on the neutron and ray should be taken into account when comparing the calculated values with experimental values. The neutron flux distribution in the full reactor lower axial two dimensional geometry has been calculated and used, together with the results obtained by the upper axial two dimensional a

Transient heat transfer from a wire inserted into a vertically mounted pipe to forced-flow subcooled liquid hydrogen

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Horie, Yuki*; Yoneda, Kazuya*; Matsuzawa, Takayuki*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*

no journal, , 

no abstracts in English

Progress in development of a wide band polarizer for ECCD system in JT-60SA

Horie, Naoyuki*; Sai, Takuma*; Omori, Kohei*; Saigusa, Mikio*; Kobayashi, Takayuki; Moriyama, Shinichi; Arata, Hiroshi*; Uno, Tsuyoshi*

no journal, , 

no abstracts in English

Magnetic and crystal structures of BaCoCaRuO

Horie, Akihiro*; Yasui, Yukio*; Igarashi, Taichi*; Yatagai, Ryo*; Yamamoto, Takafumi*; Terasaki, Ichiro*; Matsukawa, Takeshi*; Hoshikawa, Akinori*; Ishigaki, Toru*; Igawa, Naoki

no journal, , 

The magnetic and crystal structures, and magnetic properties of BaCoCaRuO have been studied by using the neutron powder diffraction and the magnetization analysis. With increasing , an antiferromagnetic transition temperature decreases such as = 88 K (=0.1), 82 K (=0.2), and 76 K (=0.3), respectively. We have observed magnetic reflections, which can not be explained by the collinear structure. Though the lattice volume increases, we have found that a Ru-Ru bond length decreases with increasing . It is considered to be related with the Ru-Ru dimerization. By the combined studies of the magnetic properties and neutron diffraction analysis, we will discuss the change of Ru-spins with varying .