Airside Heat and Mass Characteristics of Fin-And-Tube Heat Exchangers

Abstract

The airside heat transfer performance of three plain-fin and four slit-fin heat exchangers under dehumidifying conditions was examined in this study. Parameters of tube row number, fin pitch, fin type, inlet cold water temperature and frontal velocity of air are considered. The total heat transfer rate, including sensible and latent heats, and sensible heat factor are obtained by experiment. The test results indicate that the heat transfer rates of the test coils increase with air inlet velocity and fin numbers. The sensible heat factors are found to increase with both Reynolds number and inlet temperature of cold water. As for the dehumidifying conditions, the condensing rate for the humid air increases with Reynolds number but decreases as the inlet temperature of cold water increases. In addition, the heat transfer rate and the ability of dehumidification for slit-fin-type heat exchangers are superior to the plain-fin-type coils.