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Condensation heat transfer characteristics and pressure drops of R410A, R22, R32, and R290 in a multiport rectangular channel

Experiments on the two-phase flow condensation heat transfer of R410A, R22, R32, and R290 (propane) inside a multiport minichannel tube are investigated in this study. The experiments are conducted with heat fluxes in the range of 3 to 15 kW/m2, working fluids mass fluxes in the range of 50 to 500 kg/m2s, and vapor quality up to 1.0, at a fixed saturation temperature of 48 °C. The test section is an aluminum multiport minichannel tube with a hydraulic diameter equal to 0.83 mm and 18 rectangular channels. The effects of mass flux, heat flux, and thermal properties of refrigerants on the heat transfer performance and pressure drop are illustrated and analyzed. The experimental heat transfer coefficients are compared with well-known correlations. Finally, from the experimental data, a new condensation heat transfer coefficient correlation for all refrigerants is proposed.