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ISSN Online: 2377-424X

ISBN Print: 0-89116-909-1

International Heat Transfer Conference 9
August, 19-24, 1990 , Jerusalem, Israel

FILMWISE CONDENSATION OF R-113 ON HORIZONTAL INTEGRAL-FIN TUBES OF DIFFERENT DIAMETERS

Get access (open in a dialog) DOI: 10.1615/IHTC9.3620
pages 15-20

摘要

Heat-transfer measurements are reported for condensation of R-113 on a smooth tube (outside diameter 19.05 mm) and on three sets of finned tubes which differed only in root diameter. The fin-root diameters were 12.7 mm, 19.05 mm and 25.0 mm. All fins within a set of tubes had the same height and thickness of 1 mm and spacings of 0.25 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, and 4.0 mm. In addition, a special tube ("QMC tube") identical to one used by Masuda and Rose (1985) was also tested for comparison purposes. Data were taken at near-atmospheric pressure. Vapor-side, heat-transfer coefficients were determined using a "modified Wilson-plot" technique.
Results for the "QMC tube" were in excellent agreement with the earlier data of Masuda and Rose (1985), confirming the validity of both experimental measurements. Heat-transfer enhancement ratios revealed that, within the range of diameters tested, the effect of root diameter was small. A change in root diameter did not affect the optimum fin spacing which was near 0.5 mm. At this optimum fin spacing, enhancement ratios of 5.2, 5.2 and 5.6 were obtained for the small, medium and large diameter tubes, respectively.