Flow Characteristics of Condensate on a Vertical Column of Horizontal Low Finned Tubes

Abstract

Experiments were performed to study the flow characteristics of condensate on a simulated bank of horizontal low finned tubes. Two or three tubes arranged in a vertical column were set in a stationary vapor. The top tube had a longitudinal slit at the upper end through which the test liquid was fed uniformly on the tube surface. Cooling water was passed through the lower tubes. The test fluids used were R-113, methanol and normal propanol. Four major flow modes: droplet, column, column-sheet and sheet, were observed as the liquid flow rate was increased. Experimental data on the number of instantaneous falling sites, the proportion of surface area covered with the falling liquid and the flooding angle below which the inter-fin sp. ace was flooded with condensate were obtained for a range of liquid flow rates. Theoretical considerations were given to the effect of liquid flow rate on the flow mode transition and on the measured quantities.