Natural convection heat transfer from a vertical cylinder in liquid sodium
Natural convection heat transfer from a vertical cylinder in liquid sodium was experimentally studied. Two test cylinders of different dimensions were used. They were 7.62 and 17.51 mm in diameter, and 186 and 257 mm in heated length, respectively. The surface heat flux was ranged from 2×104 to 2×10...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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The Japan Society of Mechanical Engineers
2014-02-01
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| Series: | Mechanical Engineering Journal |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/mej/1/1/1_2014tep0003/_pdf/-char/en |
| _version_ | 1818987535089532928 |
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| author | Koichi HATA Yuto TAKEUCHI Katsuhiko HAMA Masahiro SHIOTSU Yasuyuki SHIRAI Katsuya FUKUDA |
| author_facet | Koichi HATA Yuto TAKEUCHI Katsuhiko HAMA Masahiro SHIOTSU Yasuyuki SHIRAI Katsuya FUKUDA |
| author_sort | Koichi HATA |
| collection | DOAJ |
| description | Natural convection heat transfer from a vertical cylinder in liquid sodium was experimentally studied. Two test cylinders of different dimensions were used. They were 7.62 and 17.51 mm in diameter, and 186 and 257 mm in heated length, respectively. The surface heat flux was ranged from 2×104 to 2×106 W/m2 at the bulk liquid temperatures of 673, 773 and 873 K. The local heat transfer coefficients on the cylinders were obtained systematically at various heights, x, from the leading edge of the heated section. On the other hand, theoretical equations for laminar natural convection heat transfer from a vertical cylinder were numerically solved by using PHOENICS code for the same conditions as the experimental ones considering the temperature dependence of thermo-physical properties concerned. The local Nusselt numbers, Nux, on the vertical cylinders obtained experimentally were compared with the corresponding theoretical values on the Nux versus modified local Rayleigh number, Rf [=Grx*Pr2/(4+9Pr1/2+10Pr)], graph. The experimental values of Nux are almost in agreement with the corresponding theoretical values of Nux with the deviations less than 20 % for the range of Rf tested here. The Nux on the rod diameter of a heat exchanger for a power plant, D=31.8 mm, were numerically analyzed by using this code. A correlation, which can describe the effects of the cylinder diameter and the cylinder height, was given based on the experimental and theoretical values. This correlation can describe the experimental and theoretical values of Nux for Rf ranging from 1.5×102 to 4.7×106 within 20 % difference. |
| first_indexed | 2024-12-20T19:08:14Z |
| format | Article |
| id | doaj.art-291d4e4685984e4bb4ac3d5b5e1e971f |
| institution | Directory Open Access Journal |
| issn | 2187-9745 |
| language | English |
| last_indexed | 2024-12-20T19:08:14Z |
| publishDate | 2014-02-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Mechanical Engineering Journal |
| spelling | doaj.art-291d4e4685984e4bb4ac3d5b5e1e971f2022-12-21T19:29:15ZengThe Japan Society of Mechanical EngineersMechanical Engineering Journal2187-97452014-02-0111TEP0003TEP000310.1299/mej.2014tep0003mejNatural convection heat transfer from a vertical cylinder in liquid sodiumKoichi HATA0Yuto TAKEUCHI1Katsuhiko HAMA2Masahiro SHIOTSU3Yasuyuki SHIRAI4Katsuya FUKUDA5Institute of Advanced Energy, Kyoto UniversityInstitute of Advanced Energy, Kyoto UniversityDept. of Energy Science and Technology, Kyoto UniversityDept. of Energy Science and Technology, Kyoto UniversityDept. of Energy Science and Technology, Kyoto UniversityDept. of Marine Engineering, Kobe UniversityNatural convection heat transfer from a vertical cylinder in liquid sodium was experimentally studied. Two test cylinders of different dimensions were used. They were 7.62 and 17.51 mm in diameter, and 186 and 257 mm in heated length, respectively. The surface heat flux was ranged from 2×104 to 2×106 W/m2 at the bulk liquid temperatures of 673, 773 and 873 K. The local heat transfer coefficients on the cylinders were obtained systematically at various heights, x, from the leading edge of the heated section. On the other hand, theoretical equations for laminar natural convection heat transfer from a vertical cylinder were numerically solved by using PHOENICS code for the same conditions as the experimental ones considering the temperature dependence of thermo-physical properties concerned. The local Nusselt numbers, Nux, on the vertical cylinders obtained experimentally were compared with the corresponding theoretical values on the Nux versus modified local Rayleigh number, Rf [=Grx*Pr2/(4+9Pr1/2+10Pr)], graph. The experimental values of Nux are almost in agreement with the corresponding theoretical values of Nux with the deviations less than 20 % for the range of Rf tested here. The Nux on the rod diameter of a heat exchanger for a power plant, D=31.8 mm, were numerically analyzed by using this code. A correlation, which can describe the effects of the cylinder diameter and the cylinder height, was given based on the experimental and theoretical values. This correlation can describe the experimental and theoretical values of Nux for Rf ranging from 1.5×102 to 4.7×106 within 20 % difference.https://www.jstage.jst.go.jp/article/mej/1/1/1_2014tep0003/_pdf/-char/ennatural convection heat transfervertical cylinderliquid sodium |
| spellingShingle | Koichi HATA Yuto TAKEUCHI Katsuhiko HAMA Masahiro SHIOTSU Yasuyuki SHIRAI Katsuya FUKUDA Natural convection heat transfer from a vertical cylinder in liquid sodium Mechanical Engineering Journal natural convection heat transfer vertical cylinder liquid sodium |
| title | Natural convection heat transfer from a vertical cylinder in liquid sodium |
| title_full | Natural convection heat transfer from a vertical cylinder in liquid sodium |
| title_fullStr | Natural convection heat transfer from a vertical cylinder in liquid sodium |
| title_full_unstemmed | Natural convection heat transfer from a vertical cylinder in liquid sodium |
| title_short | Natural convection heat transfer from a vertical cylinder in liquid sodium |
| title_sort | natural convection heat transfer from a vertical cylinder in liquid sodium |
| topic | natural convection heat transfer vertical cylinder liquid sodium |
| url | https://www.jstage.jst.go.jp/article/mej/1/1/1_2014tep0003/_pdf/-char/en |
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