Experimental investigation of condensation heat transfer characteristics of R-134a vapor in horizontal heat exchanger

الملخص EN

An experimental investigation of refrigerant R-134a two-phase flow condensation heat transfer coefficient and pressure drop in condenser tube section of refrigeration system under different operating conditions is presented.

The experimental and theoretical investigations are based on test conditions in range of 10 -17 kW/m2 for heat flux, 42-63 kg/m2s for mass flux, vapor quality 1-0.03 and saturation temperature 44 to 49˚C.

The experimental tests are conducted on test rig supplied with a test section to simulate the water cooled double pipe heat exchanger, which is designed and constructed in the present work.

“The experimental results have revealed that, the heat flux and mass flux have significant impacts on the heat transfer coefficient.

“The heat transfer coefficient was increased with increase in heat flux and mass flux at prescribed test conditions, where the enhancement in heat transfer coefficient was about 47% and 14% for relatively higher heat flux and mass flux, respectively.

“The enhancement in the heat transfer coefficient was about 51% for relatively lower saturation temperature 45.97˚C and 43% for higher vapor quality 0.88 compared to other values at constant test conditions.

“The pressure drop was higher in the range of 12% and 49% for relatively higher mass flux and heat flux respectively.

“The present work results have validated by comparison with predictive models and with similar research work results and the comparison has revealed an acceptable agreement.