There have been quite few experimental investigations in the area of condensing heat transfer to cryogenic fluids. The investigations with nitrogen and oxygen have shown reasonable agreement between experimental data and those predicted by Nusselťs theory. On the other hand, in the previous investigations with much colder fluids, such as hydrogen, deuterium and helium, the experimental condensing heat transfer coefficients are smaller than those predicted by Nusselťs theory and those differences become much larger when film Reynolds number or decreasing temperature difference across the condensate film is decreased. In the present investigation, hydrogen and nitrogen were condensed inside a vertical tube (d=15 mm, L=30 mm) under steady-state conditions respectively and condensing heat transfer coefficients were precisely measured. From the experimental resuls, the condensing heat transfer coefficients for saturated hydrogen and nitrogen vapors agree with those predicted by the Nusselťs theory within ±20%. The results of the present study suggest that deuterium and helium might also behave as predicted by the Nusselťs theory.
|ジャーナル||Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B|
|出版ステータス||Published - 2000 1|
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