ライブラリ登録: Guest

ISSN Online: 2377-424X

International Heat Transfer Conference 12
August, 18-23, 2002, Grenoble, France

Effect of Fin Tip Radius for Film Condensation on Micro-fin Surfaces

Get access (open in a dialog) DOI: 10.1615/IHTC12.640
6 pages

要約

This study provides an experimental analysis for condensation heat transfer of refrigerant R-134a on one plain surface plate and two micro-fin surface plates with fin tip radius 4.5 and 70 μm. Each plate was tested at three different orientations with heat transfer surface upward, downward and vertical. The experimental heat transfer coefficients on vertical plain surface agree very well with those predicted by Nusselt [1916] equation and Kutateladze [1963] correlation at low Reynolds number and high Reynolds number conditions respectively.
The test results show no significant difference for condensation heat transfer coefficients on upward and downward, plain and micro-fin plates surfaces because all surfaces were covered by condensate film. However, for vertical surfaces test, part of the micro-fin surface was not immersed in liquid condensate film. Surface tension force acted on the fin tip to pull down condensate to the valley of the fins and enhanced condensation heat transfer. This result provides further understanding of that the fin tip radius plays an important role on condensation heat transfer.