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Experimental study on condensation heat transfer and pressure drop of low GWP refrigerant HFO 1234 yf in a horizontal tube

Condensation heat transfer of low GWP refrigerant HFO1234yf was measured in a horizontal tube (inner diameter: 4 mm) at a mass flux range of 100 400 kg m s and different saturation temperatures (40, 45, and 50 oC), and the results were compared with that of R134a, and R32. Effects of mass flux, vapor quality, saturation temperature, and thermophysical properties on the heat transfer coefficient were analyzed. Mass flux and vapor quality were presented to primarily affect the heat transfer coefficient in shear-force dominated flow regimes, whereas the thermal conductivity and density ratio are the primary parameters as thermophysical properties influencing the heat transfer coefficient. Observed annular flow regimes agreed with Tandon's flow pattern map. The measured pressure drop compared with that predicted by the Lockhart-Matinelli correlation, Huang correlation and Haraguchi correlation. And, when comparing the experimental heat transfer coefficient with four heat transfer coefficient correlations, the Haraguchi correlation fairly agreed with the experimental data, with a 10.8 % mean deviation.