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ARTICLE
EXPERIMENTS ON DOMINANT FORCE REGIMES IN FLOW BOILING USING MINI-TUBES
Soumei Babaa,*, Nobuo Ohtania, Osamu Kawanamib, Koichi Inouec, Haruhiko Ohtaa
a Department of Aeronautics and Astronautics, Kyushu University, Fukuoka, Fukuoka 819-0395, Japan
b Department of Mechanical and System Engineering, University of Hyogo, Himeji, Hyogo, 671-2201, Japan
c Faculty of Environmental Engineering, Kitakyushu University, Kitakyushu, Fukuoka, 808-0157, Japan
* Corresponding Author: Email: -u.ac.jp
Frontiers in Heat and Mass Transfer 2012, 3(4), 1-8. https://doi.org/10.5098/hmt.v3.4.3002
Abstract
Effects of tube orientation on flow boiling heat transfer coefficients were investigated for FC72 flowing in single mini-tubes with tube diameters of
0.13 and 0.51 mm to define boundaries on a dominant force regime map. For the tube diameter of 0.51 mm, when mass velocity and vapor quality
was varied, heat transfer coefficients were influenced by tube orientation at Froude number
Fr < 4, while the effect of tube orientation on heat
transfer coefficients disappears at
Fr > 4. The results indicated that the boundary between the body force dominated and the inertia dominated
regimes was given by
Fr ≈ 4. On the other hand, for tube diameter of 0.13 mm, almost no effect of tube orientation on heat transfer coefficients was
observed for all combinations of mass velocity and vapor quality tested, where heat transfer coefficients were independent of mass velocity and vapor
quality at Weber number
We < 5, and vice versa. The results indicated that the boundary between the surface tension dominated and the inertia
dominated regimes was represented by
We ≈ 5. From the above results, the boundary between the surface tension dominated and the body force
dominated regimes was existed between
Bo = 0.51 and 0.033.
Keywords
Cite This Article
Baba, S., Ohtani, N., Kawanami, O., Inoue, K., Ohta, H. (2012). EXPERIMENTS ON DOMINANT FORCE REGIMES IN FLOW BOILING USING MINI-TUBES.
Frontiers in Heat and Mass Transfer, 3(4), 1–8.