Condensation Heat Transfer Performance of Heat Transfer Tubes with Different Wettabilities in Presence of a Large Amount of Noncondensable Gas[J]. 2015, 49(7): 30-36.
DOI:
Condensation Heat Transfer Performance of Heat Transfer Tubes with Different Wettabilities in Presence of a Large Amount of Noncondensable Gas[J]. 2015, 49(7): 30-36.DOI: 10.7652/xjtuxb201507006.
Condensation Heat Transfer Performance of Heat Transfer Tubes with Different Wettabilities in Presence of a Large Amount of Noncondensable Gas
To improve the condensation heat transfer performance of water vapor in the presence of a large amount of noncondensable gas and realize the high-efficiency recovery of industrial residual heat in electricity
chemical engineering
refrigeration and other fields
the outside condensation heat transfer performances of horizontal plain and finned tubes with different surface wettabilities were experimentally studied. The self-assembled monolayer coatings of n-octadecyl mercaptan using oxidation and etching treatments were employed to create the hydrophobic or superhydrophobic surfaces with nanostructures. The hydrophilic-hydrophobic and hydrophilic-superhydrophobic hybrid surfaces based on finned tubes were prepared. The experimental results showed that the hydrophilic-superhydrophobic hybrid finned tube achieved the highest condensation heat transfer performance in the presence of a large amount of noncondensable gases. The volume fraction of water vapor in the nitrogen-vapor mixture has important influence on the heat transfer characteristics. And as the vapor volume fraction increased
the dropwise condensation was transformed gradually to the film condensation on both superhydrophobic and hydrophilic-superhydrophobic hybrid finned tubes.
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