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Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Nonaka, Satoshi*; Inatani, Yoshifumi*
IOP Conference Series; Materials Science and Engineering, 101, p.012177_1 - 012177_8, 2015/12
Times Cited Count：0 Percentile：0.00(Thermodynamics)Transient heat transfers from PtCo wire heaters inserted into vertically-mounted pipes, through which forced flow subcooled liquid hydrogen was passed, were measured by increasing the exponential heat input with various time periods at a pressure of 0.7 MPa and inlet temperature of 21 K. The flow velocities ranged from 0.3 to 7 m/s. The PtCo wire heaters had a diameter of 1.2 mm and lengths of 60 mm, 120 mm and 200 mm and were inserted into the pipes with diameters of 5.7mm, 8.0 mm, and 5.0 mm, respectively. With increase in the heat flux to the onset of nucleate boiling, surface temperature increased along the curve predicted by the Dittus-Boelter correlation for longer period, where it can be almost regarded as steady-state. For shorter period, the heat transfer became higher than the Dittus-Boelter correlation. In nucleate boiling regime, the heat flux steeply increased to the transient critical heat flux (CHF), which became higher for shorter period. Effect of flow velocity, period, and heated geometry on the transient CHF was clarified.
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*
Journal of Superconductivity and Novel Magnetism, 28, p.1185 - 1188, 2014/09
Times Cited Count：18 Percentile：55.42(Physics, Applied)Heat transfer from a horizontal wire immersed in liquid and supercritical hydrogen was measured with a quasi-steady increase of a heat generation rate for wide range of bath temperatures and pressures. The nucleate boiling heat transfer coefficient is higher for higher pressure. The CHF is highest in the vicinity of 0.4 MPa and is expressed by Kutateladze's equation. The CHFs become higher for higher subcooling. The heat transfer under supercritical pressure is the same as natural convection heat transfer in liquid hydrogen, but it detoriorates for the heated surface temperature higher than pseudo-critical temperature. The heat transfer correlation was derived based on the experimental data.
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：2 Percentile：64.28(Engineering, Electrical & Electronic)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
cryostat with a LH 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.
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：16 Percentile：98.07(Thermodynamics)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.
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*
Journal of Physics; Conference Series, 568, p.032017_1 - 032017_5, 2014/00
Times Cited Count：5 Percentile：84.04(Physics, Applied)Forced convection heat transfer from a PtCo wire with a length of 120 mm and a diameter of 1.2 mm that was inserted into a vertically-mounted pipe with a diameter of 8.0 mm to liquid hydrogen flowing upward was measured with a quasi-steady increase of a heat generation rate for wide ranges of flow rate under saturated conditions. The pressures were varied from 0.4 MPa to 1.1 MPa. The non-boiling heat transfer characteristic agrees with that predicted by Dittus-Boelter correlation. The critical heat fluxes are higher for higher flow rates and lower pressures. Effect of Weber number on the CHF was clarified and a CHF correlation that can describe the experimental data is derived based on our correlation for a pipe.
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*; Kinoshita, Katsuhiro*
AIP Conference Proceedings 1434, p.747 - 754, 2012/06
Times Cited Count：15 Percentile：96.07(Physics, Applied)Forced flow heat transfers of liquid hydrogen through horizontally-mounted tubes with the diameter of 3.0 mm and 6.0 mm were measured at the pressure of 0.7 MPa for various inlet temperatures and flow velocities. The measured non-boiling heat transfer coefficients agree with those by the Dittus-Boelter correlation. The heat fluxes at the onset of nucleate boiling and the departure from nucleate boiling (DNB) heat fluxes, where the heat transfer continuously changes to film boiling regime, are higher for higher flow velocity, larger subcooling and larger tube diameter. The DNB heat fluxes for the horizontally-mounted tube are slightly lower than those for the vertically-mounted tube, although the effect of the tube attitude direction disappears for a small tube diameter. The measured DNB heat fluxes agree with the correlation for vertically-mounted tubes.
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.
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*; Kinoshita, Katsuhiro*
Physics Procedia, 36, p.1360 - 1365, 2012/00
Times Cited Count：10 Percentile：92.55(Physics, Particles & Fields)Heat transfers from inner side of a vertically-mounted heated tube with a length of 200.0 mm and a diameter of 6.0 mm to forced flow of liquid hydrogen were measured for wide ranges of flow rate and liquid temperature. Non-boiling heat transfer coefficients agreed well with the Dittus-Boelter equation. Departure from nucleate boiling heat fluxes (DNB) were higher for higher flow velocity and larger subcooling. The effect of the tube length on the DNB heat flux was clarified compared with our previous data. It was confirmed that the experimental data agreed well with the author's DNB correlation.
Shirai, Yasuyuki*; Tatsumoto, Hideki; Shiotsu, Masahiro*; Hata, Koichi*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*; Kinoshita, Katsuhiro*
Cryogenics, 51(6), p.295 - 299, 2011/06
Times Cited Count：49 Percentile：83.24(Thermodynamics)Heat transfer from inner side of a heated vertical pipe to liquid hydrogen flowing upward was first measured at the pressure of 0.7 MPa for wide ranges of flow rates and liquid temperatures. The heat transfer coefficients in non-boiling regime for each flow velocity were well in agreement with the Dittus-Boelter equation. The heat fluxes at the inception of boiling and the DNB heat fluxes are higher for higher flow velocity and subcooling. It was found that the trend of dependence of the DNB heat flux on flow velocity was expressed by the correlation derived by Hata et al. based on their data for subcooled flow boiling of water, although it has different propensity to subcooling.
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：23 Percentile：97.57(Physics, Multidisciplinary)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.
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 
= 6.0 mm. The effect of tube diameter and subcooling on the DNB heat flux was clarified.
Tatsumoto, Hideki; Shiotsu, Masahiro*; Kobayashi, Hiroto*; Yoshikawa, Kotaro*; Shirai, Yasuyuki*; Hata, Koichi*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*
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Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Hata, Koichi*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*
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Tatsumoto, Hideki; Shirai, Yasuyuki*; Hikawa, Kyosuke*; Hara, Yuki*; Shiotsu, Masahiro*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Yagishita, Tsuyoshi*; Nonaka, Satoshi*; Maru, Yusuke*; et al.
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Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*; Hata, Koichi*
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no abstracts in English
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Naruo, Yoshihiro*; Kobayashi, Hiroaki*; Inatani, Yoshifumi*
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Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Horie, Yuki*; Yoneda, Kazuya*; Matsuzawa, Takayuki*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*
no journal, ,
no abstracts in English
Tatsumoto, Hideki; Shirai, Yasuyuki*; Shiotsu, Masahiro*; Horie, Yuki*; Yoneda, Kazuya*; Matsuzawa, Takayuki*; Kobayashi, Hiroaki*; Naruo, Yoshihiro*; Inatani, Yoshifumi*
no journal, ,
no abstracts in English
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
