Abstract

The present study explores the two-phase flow pressure drop characteristics and flow visualizations for pure refrigerants R600a, and refrigerant mixture R410A in a smooth horizontal tube (7 mm internal diameter) uniformly heated by the resistance heating effect. The investigations were carried out at the inlet temperature range of 5oC-9oC varying the refrigerant mass flux within the range 100-400 kg/m2s, the heat fluxes within the range 3.0- 10.0 kW/m2; the average qualities of boiling refrigerant were between 0.10 and 0.95. The influence of these parameters and fluid thermo-physical properties of the two-phase pressure drop were analyzed. Moreover, the pressure drop predicted by some available models and empirical correlations in the open literature were compared with the present data.