Condensation, Heat transfer, Multiport, Minichannel, Correlation
In the present study, the heat transfer coefficients are investigated experimentally for condensation of R22, R410A, and R32 inside a horizontal multiport rectangular mini-channel tube. The multiport tube having nine channels in 0.969mm of hydraulic diameter, the experimental measurements were carried out at the fixed saturation temperature of 48oC, by the varying refrigerant mass flux from 50 to 500kg/m2s, and the heat flux range from 3 to 15kW/m2. The test section was a double tube of counter-flow type; the refrigerant was flowed condensation inside the test tube by heat exchange with cooling water flowing in the annular side. The temperature and pressure of refrigerant were measured at the inlet and outlet of the test section, and the surface temperature of tubes was measured. The effect of vapor quality, mass flux and heat flux on condensation characteristics is clarified. The experiment results were compared with the existing heat transfer coefficient correlations, and a new correlation was proposed using the present data with good prediction.