Experimental study on saturated flow boiling heat transfer of R170/R290 mixtures in a horizontal tube

Saturated flow boiling heat transfer coefficients in a horizontal tube of the binary mixtures of R170/R290 were measured. The experiments were performed at three different mixture compositions and various saturation pressures from 0.35 to 0.57 MPa. The results were obtained over the mass fluxes ranging from 63.6 to 102.5 kg m(-2) s(-1) and heat fluxes ranging from 13.1 to 65.5 kW m(-2). The influences of quality, saturation pressure, heat flux and mass flux on the heat transfer characteristic were examined and discussed. The flow pattern of mixture was shown and the transitions of flow pattern occur at higher mass flux and quality for mixtures than for pure substance. A modified correlation was developed based on the previous research of our group on the pool boiling heat transfer and the database obtained from this study. The comparison of the experimental heat transfer coefficient with the predicted value using the present correlation shows that the total mean deviation is 15.97% for R170/R290 mixtures. (C) 2009 Elsevier Ltd and IIR. All rights reserved.