Two Phase Heat Transfer Coefficient for Minichannel Condensers

Vapour compression refrigeration (VCR) system was designed, developed and fabricated for testing alternative refrigerants such as R152a, R600a, R290 and mixture of R290/R600a (50/50 by wt %) over presently used R134a with aluminium minichannel condenser. In the test set up, heater bank was provided for controlling condensation temperature and evaporator temperature along with sub-cooling and superheating temperature by using PID controllers. All the refrigerants were tested for condensation temperature ranging from 40 to 55 °C while evaporation temperature ranges from -15 to 15 °C. Refrigerant charge was reduced drastically with the minichannel condenser over the conventional condenser. Two phase condensation heat transfer coefficient correlation was developed from the experimental data points to design minichannel and conventional condenser and found in good agreement with the existing well known correlations.