Evaporation Heat Transfer and Pressure Drop of R-410A in a 5.0 mm O.D. Smooth and Microfin Tube

Abstract

R-410A's evaporation heat transfer and pressure drop data are provided for a 5.1 mm O.D. microfin tube having 40 fins with 18° helix angle and 40° fin apex angle. Tests were conducted for a range of quality (0.2–0.6), mass flux (260–433 kg/m2s), heat flux (10–20 kW/m2) and saturation temperature (8–12°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 (1.10–1.70) was slightly smaller than that of heat transfer enhancement factor (1.39–1.79). Data are compared with available heat transfer and pressure drop correlations.