Effect of vapor velocity during condensation on horizontal finned tubes

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Authors
Hopkins, Charles Louis III
Subjects
condensation
vapor velocity effects on heat-transfer coefficient
finned tubes
Advisors
Marto, P.J.
Wanniarachchi, A.S.
Date of Issue
1988-12
Date
December 1988
Publisher
Monterey, California. Naval Postgraduate School
Language
en_US
Abstract
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, 1.5, and 4.0 mm (tubes A, B, and C respectively) . Data were taken by increasing the vapor velocity from 0.4 to 1.9 m/s for R-113 and 4.8 to 31.3 m/s for steam. For both fluids, the improvement of the condensing heat-transfer coefficient with vapor velocity was smaller for the finned tubes than for the smooth tube. For R-113, the smooth tube experienced a 32 percent improvement with vapor velocity, where the finned tubes (tubes A, B and C respectively) experienced improvements of only 0, 5 and 10 percent. For steam, the smooth tube experienced a 62 percent improvement, whereas the finned tubes (tubes A, B, and C respectively) experienced improvements of only 31, 11, and 9 percent. These test results show that, although finned tubes can provide significant heat transfer enhancement over smooth tubes at low vapor velocities, the degree of enhancement becomes smaller as vapor velocity increases.
Type
Thesis
Description
URI
https://hdl.handle.net/10945/23193
Series/Report No
Department
Mechanical Engineering
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
CBT-8603582 (NSF)
Funder
National Science Foundation
Format
120 p.
Citation
Distribution Statement
Approved for public release; distribution is unlimited.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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