Gravity Controlled Condensation of an Ethanol and Water Mixture on a Horizontal Tube

Abstract

The experimental results for gravity-controlled condensation of ethanol and water vapor mixtures on a horizontal tube are presented. Dropwise, drop and streak, and ring wise condensations are observed for the ranges of ethanol vapor mass fraction W1∞>=0.2∼0.5, 0.5∼0.7 and 0.75∼0.8, respectively, while smooth-film condensation takes place for the ranges of W1∞=0∼0.2 and W1∞=0.8∼1. Previous theoritical results for the heat transfer coefficent by the present authors based on the two-phase boundary layer theory are valid for the case of smooth-film condensation, while 20 to 60% higher heat transfer coefficient values are obtained for the other cases. © 1989, The Japan Society of Mechanical Engineers. All rights reserved.