Study of vapor condensation on curvilinear fins under influence of capillary forces and gravity

Abstract

The problem on film vapor condensation on curvilinear fins is solved numerically with regard to surface tension and gravity. Steam condensation on a fin of optimized and semicircular form was calculated for various inclinations of the fin relative to the direction of gravity vector and the levels of groove flooding. The calculations showed that the average heat transfer coefficient for a semicircular fin slightly decreases with changing the fin position relative to the direction of gravity vector, at that, the “zero” flow point from which the condensate flows in different directions shifts. For an optimized fin, there is no such shift, and the heat transfer coefficient does not practically change. The top of an optimized fin with a large curvature serves as a kind of "barrier" for the flow. The heat transfer coefficients on optimized fins are significantly higher than those on semicircular fins. The amount of the level of groove flooding significantly affects the condensation efficiency as a whole; however, it does not affect the process of condensation on the convex part of fins.