Film condensation of steam on externally finned horizontal tubes
Flook, Frederick A.
MetadataShow full item record
Filmwise condensation measurements of steam were made on horizontal finned tubes under vacuum and near-atmospheric conditions. Data were obtained for copper tubes with fins of rectangular, triangular, trapezoidal, and parabolic cross sections, and for a commercially-available finned tube. A stainless steel finned tube was also tested to investigate the effect of thermal conductivity. Maximum enhancements of about 4.8 were obtained under vacuum conditions, and about 6.9 at atmospheric pressure, compared to a smooth tube having an outside diameter equal to the root diameter of the finned tubes. The optimum fin spacing was found to be about 2.0 mm for rectangularly shaped-fins with a fin thickness of 1.0 mm, and fin height of 0.5 and 1.5 mm. Fins with a parabolic shape were shown to perform better than fins of rectangular shape, and fins were shown to degrade the performance of stainless steel tubes. The effects of vapor shear were shown to have only a small influence on the steam-side heat-transfer coefficient. A theoretical model proposed by Webb et al.  was found to underpredict the experimental data. Several suggestions to modify this model are described.
Approved for public release; distribution is unlimited
NPS Report NumberNPS 69-85-002
Showing items related by title, author, creator and subject.
Bertsch, George M. (Monterey, California: Naval Postgraduate School, 1993-03);This thesis examines the pool boiling heat transfer characteristics of HCFC-124 and HCFC-124/oil mixtures with up to 10% (by weight) miscible alkylbenzene oil. One smooth and 4 enhanced tubes were tested: a 19 and 26 low ...
Hopkins, Charles Louis III (Monterey, California. Naval Postgraduate School, 1988-12);Heat-transfer measurements were made for condensation of R-113 and steam on a smooth tube and on three finned tubes with rectangular shape fins. These tubes had a fin height and width of 1.0 mm and spacings of 0.25, ...
Akcasayar, Nezih (Monterey, California. Naval Postgraduate School, 1989-12);The heat transfer characteristics of pure R-114 and R-114/oil mixtures during nucleate pool boiling from a small bundle of finned and High Flux tubes were measured. The bundles had 5 instrumented and 10 additional heated ...