Measurement and correlation of boiling heat transfer coefficient of R-1234yf in horizontal small tubes

We report experimental data of boiling heat transfer of R-1234yf in horizontal small tubes. The experimental data obtained in the horizontal circular small tubes of 1.5 and 3.0 mm inner diameter, the lengths of 1000 and 2000 mm, the mass flux range from 200-650 kg/m(2)s, the heat flux range from 5-40 kW/m(2) and saturation temperature of 10 and 15A degrees C, was used to develop a modified correlation for the heat transfer coefficient. The flow pattern of the experimental data was mapped and analyzed with existing flow pattern maps. The heat transfer coefficient was also compared with some well-known correlations.