Experimental condensing two-phase frictional pressure drop inside mini-channels. Comparisons and new model development

The present paper reports condensing two-phase flow pressure drop inside a mini-channel tube with 1.16 mm inner hydraulic diameter with R1234yf, R134a and R32. According to the available data, most of the models checked capture the trend correctly. Experimental data are analysed to show the influence of saturation temperature, mass velocities, vapour quality and fluid properties in pressure drop. Finally, a new correlation model is presented with a mean absolute relative deviation (MARD) value of 8.32% reducing the best correlation MARD by more than 34%.