Experiments are carried out on the boiling heat transfer of nonazeotropic refrigerant mixtures of HCFC22/CFC114 flowing inside a 7.9 mm ID horizontal smooth tube, Using a water-heated, double-tube type evaporator, the local heat transfer coefficients are measured for both counter and parallel flows. An empirical correlation equation is proposed for the data in the annular-flow regime, taking into account the mixture effect in the authors' previous correlation equation for pure refrigerants. The mean deviation between the calculated and measured heat transfer coefficients is 8.9% for the present experimental data and 7.1% for the data obtained by Jung. The equation reveals that the convection heat transfer is dominant due to the suppression of nucleate boiling for the mixtures.
!!!All Science Journal Classification (ASJC) codes