抄録
We developed a turbo-Brayton refrigerator with Ne gas as a working fluid for a 3θ- 66/6.9kV-2MVA superconducting transformer with coated conductors which was bath-cooled with subcooled LN 2 . The two-stage compressor and expansion turbine had non-contact magnetic bearings for a long maintenance interval. In the future, we intend to directly install a heat exchanger into the Glass-Fiber-Reinforced-Plastics cryostat of a transformer and make a heat exchange between the working fluid gas and subcooled LN 2 . In this paper we investigate the behaviour of subcooled LN 2 in a test cryostat, in which heater coils were arranged side by side with a flat plate finned-tube heat exchanger. Here a He turbo-Brayton refrigerator was used as a substitute for a Ne turbo-Brayton one. The pressure at the surface of LN 2 in the cryostat was one atmosphere. Just under the LN2 surface, a stationary layer of LN 2 was created over the depth of 20 cm and temperature dropped from 77 K to 65 K with depth while, in the lower level than that, a natural convection flow of LN 2 was formed and temperature was almost uniform over 1 m depth. The boundary plane between the stationary layer and the natural convection region was visible.
| 元の言語 | 英語 |
|---|---|
| 記事番号 | 012026 |
| ジャーナル | IOP Conference Series: Materials Science and Engineering |
| 巻 | 101 |
| 発行部数 | 1 |
| DOI | |
| 出版物ステータス | 出版済み - 12 18 2015 |
| イベント | 2015 Joint Cryogenic Engineering and International Cryogenic Materials Conferences, CEC/ICMC 2015 - Tucson, 米国 継続期間: 6 28 2015 → 7 2 2015 |
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Engineering(all)
これを引用
Development of cooling system for 66/6.9kV-20MVA REBCO superconducting transformers with Ne turbo-Brayton refrigerator and subcooled liquid nitrogen. / Iwakuma, Masataka; Adachi, K.; Yun, K.; Yoshida, K.; Sato, S.; Suzuki, Y.; Umeno, T.; Konno, M.; Hayashi, H.; Eguchi, T.; Izumi, T.; Shiohara, Y.
：: IOP Conference Series: Materials Science and Engineering, 巻 101, 番号 1, 012026, 18.12.2015.研究成果: ジャーナルへの寄稿 › Conference article
}
TY - JOUR
T1 - Development of cooling system for 66/6.9kV-20MVA REBCO superconducting transformers with Ne turbo-Brayton refrigerator and subcooled liquid nitrogen
AU - Iwakuma, Masataka
AU - Adachi, K.
AU - Yun, K.
AU - Yoshida, K.
AU - Sato, S.
AU - Suzuki, Y.
AU - Umeno, T.
AU - Konno, M.
AU - Hayashi, H.
AU - Eguchi, T.
AU - Izumi, T.
AU - Shiohara, Y.
PY - 2015/12/18
Y1 - 2015/12/18
N2 - We developed a turbo-Brayton refrigerator with Ne gas as a working fluid for a 3θ- 66/6.9kV-2MVA superconducting transformer with coated conductors which was bath-cooled with subcooled LN 2 . The two-stage compressor and expansion turbine had non-contact magnetic bearings for a long maintenance interval. In the future, we intend to directly install a heat exchanger into the Glass-Fiber-Reinforced-Plastics cryostat of a transformer and make a heat exchange between the working fluid gas and subcooled LN 2 . In this paper we investigate the behaviour of subcooled LN 2 in a test cryostat, in which heater coils were arranged side by side with a flat plate finned-tube heat exchanger. Here a He turbo-Brayton refrigerator was used as a substitute for a Ne turbo-Brayton one. The pressure at the surface of LN 2 in the cryostat was one atmosphere. Just under the LN2 surface, a stationary layer of LN 2 was created over the depth of 20 cm and temperature dropped from 77 K to 65 K with depth while, in the lower level than that, a natural convection flow of LN 2 was formed and temperature was almost uniform over 1 m depth. The boundary plane between the stationary layer and the natural convection region was visible.
AB - We developed a turbo-Brayton refrigerator with Ne gas as a working fluid for a 3θ- 66/6.9kV-2MVA superconducting transformer with coated conductors which was bath-cooled with subcooled LN 2 . The two-stage compressor and expansion turbine had non-contact magnetic bearings for a long maintenance interval. In the future, we intend to directly install a heat exchanger into the Glass-Fiber-Reinforced-Plastics cryostat of a transformer and make a heat exchange between the working fluid gas and subcooled LN 2 . In this paper we investigate the behaviour of subcooled LN 2 in a test cryostat, in which heater coils were arranged side by side with a flat plate finned-tube heat exchanger. Here a He turbo-Brayton refrigerator was used as a substitute for a Ne turbo-Brayton one. The pressure at the surface of LN 2 in the cryostat was one atmosphere. Just under the LN2 surface, a stationary layer of LN 2 was created over the depth of 20 cm and temperature dropped from 77 K to 65 K with depth while, in the lower level than that, a natural convection flow of LN 2 was formed and temperature was almost uniform over 1 m depth. The boundary plane between the stationary layer and the natural convection region was visible.
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UR - http://www.scopus.com/inward/citedby.url?scp=84959889775&partnerID=8YFLogxK
U2 - 10.1088/1757-899X/101/1/012026
DO - 10.1088/1757-899X/101/1/012026
M3 - Conference article
VL - 101
JO - IOP Conference Series: Materials Science and Engineering
JF - IOP Conference Series: Materials Science and Engineering
SN - 1757-8981
IS - 1
M1 - 012026
ER -