Effects of off-center angle on the heat transfer coefficient on vertical tier of multiple spherical surfaces

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Date

2004

Author

Kaya, Ebubekir

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The purpose of this study is to investigate the laminar film condensation phenomenon of steam on a vertical tier of multiple spherical surfaces by using both analytical and experimental methods. The analytical heat transfer results were obtained by following the Nusselt type of analysis and represented graphically. In addition, in order to observe the real behavior of the film condensation, an experimental setup was manufactured and experiments were done. In analytical section; mass flow rate, (mean) velocity, film thickness, local heat flux and local heat transfer coefficient values were obtained and plotted as depending on angular position. Moreover, mean heat flux and mean heat transfer coefficient variations were presented with respect to diameter of the sphere and sub-cooling. On the other hand, for the experimental section, heat flux and mean heat transfer coefficient values were obtained and expressed as depending on sub-cooling. To see the effects of off-center angle, setup was inclined for different angles and experiments were repeated for each inclination angle. At the end of the study, mean heat transfer coefficients belong to analytical and experimental studies were compared to each other as well as to the literature.

Subject Keywords

Steam engineering.

URI

http://etd.lib.metu.edu.tr/upload/12605714/index.pdf
https://hdl.handle.net/11511/14918

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

E. Kaya, “Effects of off-center angle on the heat transfer coefficient on vertical tier of multiple spherical surfaces,” M.S. - Master of Science, Middle East Technical University, 2004.