Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Ito, Kei; Ezure, Toshiki; Ohno, Shuji; Kamide, Hideki
no journal, ,
A free surface vortex is considered as one of significant phenomena in sodium-cooled fast reactors, which may cause gas entrainment (GE). In our past studies, the free surface vortex is approximated by the Burgers vortex model which assumes unrealistic downward velocity distribution in redial direction. In this study, a new theoretical vortex model with realistic downward velocity distribution is proposed. This model is derived from the axisymmetric Navier-Stokes equation and the downward velocity is defined to be zero at the vortex center and to approach asymptotically to zero at infinity. As the verification, the new model is applied to the evaluation of a simple vortex experiment, and shows good agreements with the experimental data in terms of the free surface shape.
Kondo, Hiroo; Kanemura, Takuji; Furukawa, Tomohiro; Hirakawa, Yasushi; Wakai, Eiichi
no journal, ,
EVEDA (Engineering Validation and Engineering Design Activity) Li Test Loop, which simulates the hydraulic condition of the Li target and the purification system of the IFMIF Li facility, is under operation in a frame work of the IFMIF/EVEDA. In this study, flow-induced noise of the Li target flowing in vacuum conditions was detected by an acoustic emission sensor, and was normalized by cavitation number.
Kanemura, Takuji; Kondo, Hiroo; Furukawa, Tomohiro; Hirakawa, Yasushi; Wakai, Eiichi
no journal, ,
A high-speed (15 m/s) liquid lithium (Li) jet is planned to be utilized as the target of two 40 MeV - 125 mA deuteron beams in the International Fusion Materials Irradiation Facility. The target thickness is required to be maintained within 25 
1 mm under a vacuum condition of 10
Pa. This paper presents the measurement results of the Li target thickness at the velocity of 10, 15 and 20 m/s under an Ar pressure of 0.12 MPa. The target was found to be rather smooth and approx. 26 mm in thickness on average at the all velocities in the region of interest. As for temporal variation, average and maximum wave amplitude were approx. 0.3 and 1.5 mm respectively at the all velocities in the same region. Therefore, it was found that the Li target stability exceeded slightly more than the design requirement under an Ar pressure of 0.12 MPa. The next step is to measure the Li target under a vacuum condition and to evaluate whether the deviation is or not an issue on the target design.
Nagatake, Taku; Takase, Kazuyuki; Furuya, Masahiro*; Yoshida, Hiroyuki; Nagase, Fumihisa
no journal, ,
no abstracts in English
Furuya, Masahiro*; Nagatake, Taku; Takase, Kazuyuki; Yoshida, Hiroyuki; Nagase, Fumihisa
no journal, ,
no abstracts in English
Ote, Naosuke*; Koizumi, Yasuo*; Kamide, Hideki; Ohno, Shuji; Ito, Kei
no journal, ,
A sodium-cooled fast breeder reactor is now at the development stage in Japan. One concern for safety is cover gas entrainment into the sodium coolant. The gas entrainment rate into liquid by the vortex formed on the free surface was examined experimentally. A hollow vortex was formed on the free surface in the test vessel. The air was entrained under the free surface of the vortex and carried away from the bottom of the vessel. The flow state of the gas entrainment was visually observed by using a high speed video camera. The gas entrainment rate into liquid was measured. In the previous study, test fluid was water. Kerosene and 20 cSt silicone oil were newly introduced as the test fluid to examine the effect of the physical properties on the gas entrainment phenomena.