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Journal Articles

Development of an experimental system for characterization of high-temperature superconductors cooled by liquid hydrogen under the external magnetic field

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*

Journal of Physics; Conference Series, 507(2), p.022042_1 - 022042_4, 2014/05

 Times Cited Count:1 Percentile:55.09

An experimental system has been developed to investigate electro-magnetic properties of high-Tc superconductors cooled by liquid hydrogen under the external magnetic field of up to 7 T. A LH$$_{2}$$ cryostat with a LH$$_{2}$$ inventory of 61 L is concentrically mounted on the inside of a LHe cryostat to cool a NbTi superconducting magnet. The experimental system is installed in an explosion-proof room and explosion proof electrical devices are used. The current leads are covered with an enclosure filled with nitrogen gas. A remote control system has been developed to maintain safety distance. Furthermore, the effects of stray magnetic field on the existing and the new devices are investigated and electro-magnetic shielding panels and enclosure made of iron were designed using ANSYS analysis. It is confirmed through the cryogenic test that the experimental system meets the design requirements.

Journal Articles

Forced convection heat transfer of saturated liquid hydrogen in vertically-mounted heated pipes

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*

AIP Conference Proceedings 1573, p.44 - 51, 2014/01

 Times Cited Count:7 Percentile:94.98

Heat transfers from the inner side of vertically-mounted heated pipes to forced flow of saturated liquid hydrogen were measured with a quasi-steady increase of a heat generation rate for wide ranges of flow rate and saturated pressure. The tube heaters have lengths L of 100 mm and 167 mm with the diameter D of 4 mm and lengths of 150 mm and 250 mm with the diameter of 6 mm. The heat fluxes at departure from nucleate boiling (DNB) were higher for higher flow velocity, lower pressures and shorter L/D. The effect of L/D on the DNB heat flux was clarified. It is confirmed that our DNB correlation can describe the experimental data.

Journal Articles

Effect of a heated pipe length on DNB heat flux in forced flow of liquid hydrogen

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*; Narita, Norihiko*

Proceedings of 24th International Cryogenic Engineering Conference (ICEC 24) and International Cryogenic Materials Conference 2012 (ICMC 2012) (CD-ROM), p.157 - 160, 2012/05

The heat transfer in a forced flow of saturated liquid hydrogen was measured using vertically-mounted heated pipes with an inner diameter d of 6.0 mm and lengths L of 50, 100, 200 and 250 mm for wide ranges of flow velocity and pressure. The heat fluxes at departure from nucleate boiling were higher for higher flow velocities, lower pressures and shorter L. The effect of L on the DNB heat flux was clarified and could be described by the modified authors' DNB correlation.

Journal Articles

Development of a thermal-hydraulics experimental system for high Tc superconductors cooled by liquid hydrogen

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*; Kato, Takashi; Futakawa, Masatoshi; Kinoshita, Katsuhiro*

Journal of Physics; Conference Series, 234, p.032056_1 - 032056_9, 2010/07

 Times Cited Count:15 Percentile:96.77

A thermal-hydraulics experimental system of liquid hydrogen was developed in order to investigate the forced flow heat transfer characteristics in the various cooling channels for wide ranges of subcoolings, flow velocities, and pressures up to supercritical. Forced flow through the channel is produced by adjusting the pressure difference between the tanks and the valve opening. The mass flow rate is measured from the weight change of the main tank. For the explosion protection, electrical equipments are covered with a nitrogen gas blanket layer and a remote control system has been established. The first cryogenic performance tests have confirmed that the experimental system has satisfied with the required performances. The forced convection heat transfer characteristics have been successfully measured at the pressure of 0.7 MPa for various flow velocities.

Journal Articles

Forced convection heat transfer of subcooled liquid nitrogen in a vertical tube

Tatsumoto, Hideki; Shirai, Yasuyuki*; Hata, Koichi*; Kato, Takashi; Futakawa, Masatoshi; Shiotsu, Masahiro*

Journal of Physics; Conference Series, 234, p.032057_1 - 032057_8, 2010/07

 Times Cited Count:3 Percentile:60.61

Experimental research on forced convection heat transfer of subcooled liquid nitrogen ranging from the pressures of 0.3 MPa to its supercritical pressure is carried out for wide ranges of inlet temperature and flow velocity. The heat transfer coefficients in non-boiling region and the DNB heat fluxes are higher for higher flow velocity and higher subcooling. The heat transfer coefficients in the non-boiling region agree well with those by the Dittus-Boelter correlation, although they are unaffected by the flow velocity for $$Re$$ $$<$$ 8000. The lowest limits agree with those obtained for no forced flow. The correlation of DNB heat flux that can describe the experimental data is presented. The heat transfer characteristics of supercritical nitrogen can be predicted by authors'correlation.

Journal Articles

Forced convection heat transfer of subcooled liquid hydrogen in a small tube

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*; Kato, Takashi; Futakawa, Masatoshi; Kinoshita, Katsuhiro*

Proceedings of International Cryogenic Engineering Conference 23 (ICEC-23) and International Cryogenic Materials Conference 2010 (ICMC 2010), p.491 - 496, 2010/07

Forced flow heat transfers of liquid hydrogen through a vertical tube with the diameter, d, of 3.0 mm were measured at the pressure of 0.7 MPa for various inlet temperatures and flow velocities. The non-boiling heat transfer coefficients agreed with those by the Dittus-Boelter correlation. The heat fluxes at the inception of boiling and the departure from nucleate boiling (DNB) heat fluxes were higher for higher flow velocity and subcooling. The DNB heat fluxes were higher for larger diameter, compared with those for $$d$$ = 6.0 mm. The effect of tube diameter and subcooling on the DNB heat flux was clarified.

Journal Articles

Forced convection heat transfer of nitrogen at supercritical pressure

Tatsumoto, Hideki; Shirai, Yasuyuki*; Hata, Koichi*; Kato, Takashi; Shiotsu, Masahiro*

Proceedings of International Cryogenic Engineering Conference 22 (ICEC-22) and International Cryogenic Materials Conference 20 (ICMC 2008), p.383 - 388, 2009/00

Forced flow heat transfers of supercritical nitrogen in a horizontal tube was measured for wide range of inlet temperature and flow velocity conditions. The heat transfer coefficients agreed well with those predicted by Dittus-Boelter correlation for the surface temperature lower than pseudo-critical temperature, Tc'. When the surface temperature exceeds Tc', they become lower than those by the correlation. The heat transfer coefficients at a certain wall temperature became lower with decrease in Reynolds number (Re) down to about 8000. Further decrease in Re did not affect the heat transfer coefficients. The lowest limits agreed with those obtained for natural convection.

Journal Articles

Forced convection heat transfer to supercritical fluids

Shiotsu, Masahiro*; Tatsumoto, Hideki; Shirai, Yasuyuki*

Proceedings of International Cryogenic Engineering Conference 22 (ICEC-22) and International Cryogenic Materials Conference 20 (ICMC 2008), p.359 - 364, 2008/07

In designing a superconducting coil wound with Cable in Conduit Conductor cooled by supercritical helium, accurate knowledge of heat transfer in forced flow of He I under supercritical pressure is necessary. The authors performed experiments on heat transfer from a test plate in a horizontal duct cooled by supercritical helium. On the other hand, there have been many experimental data and correlations for non-cryogenic fluids such as water and CO$$_{2}$$ at supercritical pressures. Most of these data are on far longer tubes compared with our data for helium, and ratios of wall temperature increase to the critical temperature are far lower than that for helium. In this work, our data for supercritical helium above mentioned are compared with the correlations for the non-cryogenic fluids. The data are not predicted well by the correlations. The reasons of the discrepancies are considered and a new generalized correlation is presented.

Journal Articles

Numerical analysis of forced convection heat transfer of subcooled liquid nitrogen

Tatsumoto, Hideki; Shirai, Yasuyuki*; Hata, Koichi*; Kato, Takashi; Aso, Tomokazu; Otsu, Kiichi; Shiotsu, Masahiro*

IEEE Transactions on Applied Superconductivity, 18(2), p.1483 - 1486, 2008/06

 Times Cited Count:4 Percentile:32.09(Engineering, Electrical & Electronic)

The knowledge of forced flow heat transfer of liquid hydrogen is important for cooling design of hydrogen moderator system and HTS superconducting magnets such as MgB$$_{2}$$ magnet. The use of a CFD code is necessary to understand the heat transport phenomena in the practical cooling channel of the magnets. As a first step of the study, forced flow heat transfer of liquid nitrogen in a horizontal tube, instead of liquid hydrogen, was analyzed in this work by using a CFD code. The solutions were compared with the authors' experimental data under the corresponding conditions. The solutions obtained by using the low Reynolds number ${it k-$epsilon$}$ model as a turbulent model agreed well with the experimental data for the Reynolds numbers (${it Re}$) higher than 1$$times$$$$10^{4}$$. For ${it Re}$ $$<$$ 1$$times$$$$10^{4}$$, the solutions become lower than the experimental data. The heat transport mechanism in the horizontal tube was also clarified by the analyses.

Journal Articles

Forced convection heat transfer of subcooled liquid nitrogen in horizontal tube

Tatsumoto, Hideki; Shirai, Yasuyuki*; Hata, Koichi*; Kato, Takashi; Shiotsu, Masahiro*

AIP Conference Proceedings 985, p.665 - 672, 2008/03

The knowledge of forced convection heat transfer of liquid hydrogen is important for the cooling design of a material of a cold neutron moderator. An experimental apparatus that obtain forced flow without a pump was developed. As a first step of the study, the forced flow heat transfer of subcooled liquid nitrogen in a horizontal tube, instead of liquid hydrogen, was measured for the pressures (0.3 to 2.5 MPa). The inlet temperature was varied from 78 K to around its saturation temperature. The flow velocity was varied from 0.1 to 7 m/s. The heat transfer coefficients in non boiling region and the DNB heat fluxes were higher for higher flow velocity and higher subcooling. The measured values of Nu/Pr$$^{0.4}$$ in non-boiling region were proportional to Re to the power of 0.8. With decrease in Re, they approached a constant value corresponding to that in a pool of liquid nitrogen. The correlation of DNB derived here can describe the experimental data within 15% difference was derived.

JAEA Reports

None

; Shiotsu, Masahiro*; Hata, Koichi*; Shirai, Yasuyuki*; *

JNC TY9400 2002-004, 95 Pages, 2002/03

JNC-TY9400-2002-004.pdf:2.59MB

None

JAEA Reports

None

Shiotsu, Masahiro*; Hata, Koichi*; *; Shirai, Yasuyuki*; *;

PNC TY9604 98-002, 28 Pages, 1998/03

PNC-TY9604-98-002.pdf:0.7MB

no abstracts in English

JAEA Reports

None

Shiotsu, Masahiro*; Hata, Koichi*; *; Shirai, Yasuyuki*; *;

PNC TY9604 97-002, 15 Pages, 1997/03

PNC-TY9604-97-002.pdf:0.41MB

no abstracts in English

Oral presentation

Thermal-hydraulics experimental system of liquid hydrogen for HTC superconductors; Design and test procedure

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*; Hata, Koichi*

no journal, , 

no abstracts in English

Oral presentation

Forced flow boiling heat transfer of supercritical hydrogen

Tatsumoto, Hideki; Shiotsu, Masahiro*; Kobayashi, Hiroto*; Yoshikawa, Kotaro*; Shirai, Yasuyuki*; Hata, Koichi*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*

no journal, , 

no abstracts in English

Oral presentation

Forced convection heat transfer of liquid hydrogen; Effect of heated length

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*

no journal, , 

no abstracts in English

Oral presentation

Development of an experimental system for the measurement of properties of liquid hydrogen cooled superconductor under magnetic field

Tatsumoto, Hideki; Shirai, Yasuyuki*; Hikawa, Kyosuke*; Hara, Yuki*; Shiotsu, Masahiro*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Yagishita, Tsuyoshi*; Nonaka, Satoshi*; Maru, Yusuke*; et al.

no journal, , 

no abstracts in English

Oral presentation

Forced convection heat transfer of liquid hydrogen in vertically-mounted heated tubes

Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*

no journal, , 

no abstracts in English

Oral presentation

Transient heat transfer from a wire inserted into a vertically-mounted pipe to a forced flow of 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

Oral presentation

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

Oral presentation

DNB heat flux on wire heaters inserted into a vertically mounted pipe to forced-flow of subcooled liquid hydrogen

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

no journal, , 

no abstracts in English

21 (Records 1-20 displayed on this page)