CONDENSATION HEAT TRANSFER AND PRESSURE DROP OF R-410A IN A 5.0 MM O.D. SMOOTH AND MICROFIN TUBE

Abstract

R-410A condensation heat transfer and pressure drop data are provided for a 5.0 mm O.D. microfin tube having 40 fins with 18 degree helix angle and 40 degree fin apex angle. Tests were conducted for a range of quality (0.2 ~ 0.8), mass flux (346 ~ 692 kg/m2s) and saturation temperature (45 ~ 55°C). Data are compared with smooth tube counterpart. It was found that both heat transfer coefficient and pressure drop increased as mass flux increased. The range of pressure drop penalty factor (1.83 ~ 2.62) was slightly larger than that of heat transfer enhancement factor (1.24 ~ 1.66). Data are compared with available heat transfer and pressure drop correlations.