Abstract
The present study investigates the characteristics of two-phase flow pressure drop for R-141b in a horizontal adiabatic stainless-steel tube and a diabatic glass tube with inner diameters of 9.5 mm and 10.2 mm, respectively. The operating range of refrigerant mass flux is between 1163 and 1768 kg/m2s. The two-phase flow patterns are visualized in the heating glass tube, which is in the very upstream of the stainless-steel tube, and the effect of vapor quality and mass flux on pressure drop is demonstrated with the flow pattern. The Friedel correlation is also modified to predict the two-phase frictional multiplier of R-141b in the horizontal tube in the present study. In addition, correlations of two-phase frictional pressure drop in the diabatic glass tube are also developed.